diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 1a9f89a..c658e5d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1465,6 +1465,14 @@ as early as possible in order to facilitate early boot debugging. + ftrace_boot_snapshot + [FTRACE] On boot up, a snapshot will be taken of the + ftrace ring buffer that can be read at: + /sys/kernel/tracing/snapshot. + This is useful if you need tracing information from kernel + boot up that is likely to be overridden by user space + start up functionality. + ftrace_dump_on_oops[=orig_cpu] [FTRACE] will dump the trace buffers on oops. If no parameter is passed, ftrace will dump diff --git a/Documentation/trace/index.rst b/Documentation/trace/index.rst index 3769b9b..3a47aa8 100644 --- a/Documentation/trace/index.rst +++ b/Documentation/trace/index.rst @@ -30,3 +30,4 @@ Linux Tracing Technologies stm sys-t coresight/index + user_events diff --git a/Documentation/trace/user_events.rst b/Documentation/trace/user_events.rst new file mode 100644 index 0000000..bddedab --- /dev/null +++ b/Documentation/trace/user_events.rst @@ -0,0 +1,216 @@ +========================================= +user_events: User-based Event Tracing +========================================= + +:Author: Beau Belgrave + +Overview +-------- +User based trace events allow user processes to create events and trace data +that can be viewed via existing tools, such as ftrace, perf and eBPF. +To enable this feature, build your kernel with CONFIG_USER_EVENTS=y. + +Programs can view status of the events via +/sys/kernel/debug/tracing/user_events_status and can both register and write +data out via /sys/kernel/debug/tracing/user_events_data. + +Programs can also use /sys/kernel/debug/tracing/dynamic_events to register and +delete user based events via the u: prefix. The format of the command to +dynamic_events is the same as the ioctl with the u: prefix applied. + +Typically programs will register a set of events that they wish to expose to +tools that can read trace_events (such as ftrace and perf). The registration +process gives back two ints to the program for each event. The first int is the +status index. This index describes which byte in the +/sys/kernel/debug/tracing/user_events_status file represents this event. The +second int is the write index. This index describes the data when a write() or +writev() is called on the /sys/kernel/debug/tracing/user_events_data file. + +The structures referenced in this document are contained with the +/include/uap/linux/user_events.h file in the source tree. + +**NOTE:** *Both user_events_status and user_events_data are under the tracefs +filesystem and may be mounted at different paths than above.* + +Registering +----------- +Registering within a user process is done via ioctl() out to the +/sys/kernel/debug/tracing/user_events_data file. The command to issue is +DIAG_IOCSREG. + +This command takes a struct user_reg as an argument:: + + struct user_reg { + u32 size; + u64 name_args; + u32 status_index; + u32 write_index; + }; + +The struct user_reg requires two inputs, the first is the size of the structure +to ensure forward and backward compatibility. The second is the command string +to issue for registering. Upon success two outputs are set, the status index +and the write index. + +User based events show up under tracefs like any other event under the +subsystem named "user_events". This means tools that wish to attach to the +events need to use /sys/kernel/debug/tracing/events/user_events/[name]/enable +or perf record -e user_events:[name] when attaching/recording. + +**NOTE:** *The write_index returned is only valid for the FD that was used* + +Command Format +^^^^^^^^^^^^^^ +The command string format is as follows:: + + name[:FLAG1[,FLAG2...]] [Field1[;Field2...]] + +Supported Flags +^^^^^^^^^^^^^^^ +**BPF_ITER** - EBPF programs attached to this event will get the raw iovec +struct instead of any data copies for max performance. + +Field Format +^^^^^^^^^^^^ +:: + + type name [size] + +Basic types are supported (__data_loc, u32, u64, int, char, char[20], etc). +User programs are encouraged to use clearly sized types like u32. + +**NOTE:** *Long is not supported since size can vary between user and kernel.* + +The size is only valid for types that start with a struct prefix. +This allows user programs to describe custom structs out to tools, if required. + +For example, a struct in C that looks like this:: + + struct mytype { + char data[20]; + }; + +Would be represented by the following field:: + + struct mytype myname 20 + +Deleting +----------- +Deleting an event from within a user process is done via ioctl() out to the +/sys/kernel/debug/tracing/user_events_data file. The command to issue is +DIAG_IOCSDEL. + +This command only requires a single string specifying the event to delete by +its name. Delete will only succeed if there are no references left to the +event (in both user and kernel space). User programs should use a separate file +to request deletes than the one used for registration due to this. + +Status +------ +When tools attach/record user based events the status of the event is updated +in realtime. This allows user programs to only incur the cost of the write() or +writev() calls when something is actively attached to the event. + +User programs call mmap() on /sys/kernel/debug/tracing/user_events_status to +check the status for each event that is registered. The byte to check in the +file is given back after the register ioctl() via user_reg.status_index. +Currently the size of user_events_status is a single page, however, custom +kernel configurations can change this size to allow more user based events. In +all cases the size of the file is a multiple of a page size. + +For example, if the register ioctl() gives back a status_index of 3 you would +check byte 3 of the returned mmap data to see if anything is attached to that +event. + +Administrators can easily check the status of all registered events by reading +the user_events_status file directly via a terminal. The output is as follows:: + + Byte:Name [# Comments] + ... + + Active: ActiveCount + Busy: BusyCount + Max: MaxCount + +For example, on a system that has a single event the output looks like this:: + + 1:test + + Active: 1 + Busy: 0 + Max: 4096 + +If a user enables the user event via ftrace, the output would change to this:: + + 1:test # Used by ftrace + + Active: 1 + Busy: 1 + Max: 4096 + +**NOTE:** *A status index of 0 will never be returned. This allows user +programs to have an index that can be used on error cases.* + +Status Bits +^^^^^^^^^^^ +The byte being checked will be non-zero if anything is attached. Programs can +check specific bits in the byte to see what mechanism has been attached. + +The following values are defined to aid in checking what has been attached: + +**EVENT_STATUS_FTRACE** - Bit set if ftrace has been attached (Bit 0). + +**EVENT_STATUS_PERF** - Bit set if perf/eBPF has been attached (Bit 1). + +Writing Data +------------ +After registering an event the same fd that was used to register can be used +to write an entry for that event. The write_index returned must be at the start +of the data, then the remaining data is treated as the payload of the event. + +For example, if write_index returned was 1 and I wanted to write out an int +payload of the event. Then the data would have to be 8 bytes (2 ints) in size, +with the first 4 bytes being equal to 1 and the last 4 bytes being equal to the +value I want as the payload. + +In memory this would look like this:: + + int index; + int payload; + +User programs might have well known structs that they wish to use to emit out +as payloads. In those cases writev() can be used, with the first vector being +the index and the following vector(s) being the actual event payload. + +For example, if I have a struct like this:: + + struct payload { + int src; + int dst; + int flags; + }; + +It's advised for user programs to do the following:: + + struct iovec io[2]; + struct payload e; + + io[0].iov_base = &write_index; + io[0].iov_len = sizeof(write_index); + io[1].iov_base = &e; + io[1].iov_len = sizeof(e); + + writev(fd, (const struct iovec*)io, 2); + +**NOTE:** *The write_index is not emitted out into the trace being recorded.* + +EBPF +---- +EBPF programs that attach to a user-based event tracepoint are given a pointer +to a struct user_bpf_context. The bpf context contains the data type (which can +be a user or kernel buffer, or can be a pointer to the iovec) and the data +length that was emitted (minus the write_index). + +Example Code +------------ +See sample code in samples/user_events. diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 9999e29..37b6191 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -30,6 +30,12 @@ #define ARCH_SUPPORTS_FTRACE_OPS 0 #endif +#ifdef CONFIG_TRACING +extern void ftrace_boot_snapshot(void); +#else +static inline void ftrace_boot_snapshot(void) { } +#endif + #ifdef CONFIG_FUNCTION_TRACER struct ftrace_ops; struct ftrace_regs; @@ -215,7 +221,10 @@ struct ftrace_ops_hash { void ftrace_free_init_mem(void); void ftrace_free_mem(struct module *mod, void *start, void *end); #else -static inline void ftrace_free_init_mem(void) { } +static inline void ftrace_free_init_mem(void) +{ + ftrace_boot_snapshot(); +} static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { } #endif diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index dcea51f..6c7ae3c 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -315,6 +315,7 @@ enum { TRACE_EVENT_FL_KPROBE_BIT, TRACE_EVENT_FL_UPROBE_BIT, TRACE_EVENT_FL_EPROBE_BIT, + TRACE_EVENT_FL_CUSTOM_BIT, }; /* @@ -328,6 +329,9 @@ enum { * KPROBE - Event is a kprobe * UPROBE - Event is a uprobe * EPROBE - Event is an event probe + * CUSTOM - Event is a custom event (to be attached to an exsiting tracepoint) + * This is set when the custom event has not been attached + * to a tracepoint yet, then it is cleared when it is. */ enum { TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT), @@ -339,6 +343,7 @@ enum { TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), TRACE_EVENT_FL_EPROBE = (1 << TRACE_EVENT_FL_EPROBE_BIT), + TRACE_EVENT_FL_CUSTOM = (1 << TRACE_EVENT_FL_CUSTOM_BIT), }; #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE) @@ -440,7 +445,9 @@ static inline bool bpf_prog_array_valid(struct trace_event_call *call) static inline const char * trace_event_name(struct trace_event_call *call) { - if (call->flags & TRACE_EVENT_FL_TRACEPOINT) + if (call->flags & TRACE_EVENT_FL_CUSTOM) + return call->name; + else if (call->flags & TRACE_EVENT_FL_TRACEPOINT) return call->tp ? call->tp->name : NULL; else return call->name; @@ -903,3 +910,18 @@ perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type, #endif #endif /* _LINUX_TRACE_EVENT_H */ + +/* + * Note: we keep the TRACE_CUSTOM_EVENT outside the include file ifdef protection. + * This is due to the way trace custom events work. If a file includes two + * trace event headers under one "CREATE_CUSTOM_TRACE_EVENTS" the first include + * will override the TRACE_CUSTOM_EVENT and break the second include. + */ + +#ifndef TRACE_CUSTOM_EVENT + +#define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print) +#define DEFINE_CUSTOM_EVENT(template, name, proto, args) +#define TRACE_CUSTOM_EVENT(name, proto, args, struct, assign, print) + +#endif /* ifdef TRACE_CUSTOM_EVENT (see note above) */ diff --git a/include/trace/define_custom_trace.h b/include/trace/define_custom_trace.h new file mode 100644 index 0000000..5827a4c --- /dev/null +++ b/include/trace/define_custom_trace.h @@ -0,0 +1,77 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Trace files that want to automate creation of all tracepoints defined + * in their file should include this file. The following are macros that the + * trace file may define: + * + * TRACE_SYSTEM defines the system the tracepoint is for + * + * TRACE_INCLUDE_FILE if the file name is something other than TRACE_SYSTEM.h + * This macro may be defined to tell define_trace.h what file to include. + * Note, leave off the ".h". + * + * TRACE_INCLUDE_PATH if the path is something other than core kernel include/trace + * then this macro can define the path to use. Note, the path is relative to + * define_trace.h, not the file including it. Full path names for out of tree + * modules must be used. + */ + +#ifdef CREATE_CUSTOM_TRACE_EVENTS + +/* Prevent recursion */ +#undef CREATE_CUSTOM_TRACE_EVENTS + +#include + +#undef TRACE_CUSTOM_EVENT +#define TRACE_CUSTOM_EVENT(name, proto, args, tstruct, assign, print) + +#undef DEFINE_CUSTOM_EVENT +#define DEFINE_CUSTOM_EVENT(template, name, proto, args) + +#undef TRACE_INCLUDE +#undef __TRACE_INCLUDE + +#ifndef TRACE_INCLUDE_FILE +# define TRACE_INCLUDE_FILE TRACE_SYSTEM +# define UNDEF_TRACE_INCLUDE_FILE +#endif + +#ifndef TRACE_INCLUDE_PATH +# define __TRACE_INCLUDE(system) +# define UNDEF_TRACE_INCLUDE_PATH +#else +# define __TRACE_INCLUDE(system) __stringify(TRACE_INCLUDE_PATH/system.h) +#endif + +# define TRACE_INCLUDE(system) __TRACE_INCLUDE(system) + +/* Let the trace headers be reread */ +#define TRACE_CUSTOM_MULTI_READ + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +#ifdef TRACEPOINTS_ENABLED +#include +#endif + +#undef TRACE_CUSTOM_EVENT +#undef DECLARE_CUSTOM_EVENT_CLASS +#undef DEFINE_CUSTOM_EVENT +#undef TRACE_CUSTOM_MULTI_READ + +/* Only undef what we defined in this file */ +#ifdef UNDEF_TRACE_INCLUDE_FILE +# undef TRACE_INCLUDE_FILE +# undef UNDEF_TRACE_INCLUDE_FILE +#endif + +#ifdef UNDEF_TRACE_INCLUDE_PATH +# undef TRACE_INCLUDE_PATH +# undef UNDEF_TRACE_INCLUDE_PATH +#endif + +/* We may be processing more files */ +#define CREATE_CUSTOM_TRACE_POINTS + +#endif /* CREATE_CUSTOM_TRACE_POINTS */ diff --git a/include/trace/stages/init.h b/include/trace/stages/init.h new file mode 100644 index 0000000..000bcfc --- /dev/null +++ b/include/trace/stages/init.h @@ -0,0 +1,37 @@ + +#define __app__(x, y) str__##x##y +#define __app(x, y) __app__(x, y) + +#define TRACE_SYSTEM_STRING __app(TRACE_SYSTEM_VAR,__trace_system_name) + +#define TRACE_MAKE_SYSTEM_STR() \ + static const char TRACE_SYSTEM_STRING[] = \ + __stringify(TRACE_SYSTEM) + +TRACE_MAKE_SYSTEM_STR(); + +#undef TRACE_DEFINE_ENUM +#define TRACE_DEFINE_ENUM(a) \ + static struct trace_eval_map __used __initdata \ + __##TRACE_SYSTEM##_##a = \ + { \ + .system = TRACE_SYSTEM_STRING, \ + .eval_string = #a, \ + .eval_value = a \ + }; \ + static struct trace_eval_map __used \ + __section("_ftrace_eval_map") \ + *TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a + +#undef TRACE_DEFINE_SIZEOF +#define TRACE_DEFINE_SIZEOF(a) \ + static struct trace_eval_map __used __initdata \ + __##TRACE_SYSTEM##_##a = \ + { \ + .system = TRACE_SYSTEM_STRING, \ + .eval_string = "sizeof(" #a ")", \ + .eval_value = sizeof(a) \ + }; \ + static struct trace_eval_map __used \ + __section("_ftrace_eval_map") \ + *TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a diff --git a/include/trace/stages/stage1_defines.h b/include/trace/stages/stage1_defines.h new file mode 100644 index 0000000..a167834 --- /dev/null +++ b/include/trace/stages/stage1_defines.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 1 definitions for creating trace events */ + +#undef __field +#define __field(type, item) type item; + +#undef __field_ext +#define __field_ext(type, item, filter_type) type item; + +#undef __field_struct +#define __field_struct(type, item) type item; + +#undef __field_struct_ext +#define __field_struct_ext(type, item, filter_type) type item; + +#undef __array +#define __array(type, item, len) type item[len]; + +#undef __dynamic_array +#define __dynamic_array(type, item, len) u32 __data_loc_##item; + +#undef __string +#define __string(item, src) __dynamic_array(char, item, -1) + +#undef __string_len +#define __string_len(item, src, len) __dynamic_array(char, item, -1) + +#undef __bitmask +#define __bitmask(item, nr_bits) __dynamic_array(char, item, -1) + +#undef __sockaddr +#define __sockaddr(field, len) __dynamic_array(u8, field, len) + +#undef __rel_dynamic_array +#define __rel_dynamic_array(type, item, len) u32 __rel_loc_##item; + +#undef __rel_string +#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) + +#undef __rel_string_len +#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) + +#undef __rel_bitmask +#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(char, item, -1) + +#undef __rel_sockaddr +#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) + +#undef TP_STRUCT__entry +#define TP_STRUCT__entry(args...) args diff --git a/include/trace/stages/stage2_defines.h b/include/trace/stages/stage2_defines.h new file mode 100644 index 0000000..42fd1e8 --- /dev/null +++ b/include/trace/stages/stage2_defines.h @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 2 definitions for creating trace events */ + +#undef TRACE_DEFINE_ENUM +#define TRACE_DEFINE_ENUM(a) + +#undef TRACE_DEFINE_SIZEOF +#define TRACE_DEFINE_SIZEOF(a) + +#undef __field +#define __field(type, item) + +#undef __field_ext +#define __field_ext(type, item, filter_type) + +#undef __field_struct +#define __field_struct(type, item) + +#undef __field_struct_ext +#define __field_struct_ext(type, item, filter_type) + +#undef __array +#define __array(type, item, len) + +#undef __dynamic_array +#define __dynamic_array(type, item, len) u32 item; + +#undef __string +#define __string(item, src) __dynamic_array(char, item, -1) + +#undef __string_len +#define __string_len(item, src, len) __dynamic_array(char, item, -1) + +#undef __bitmask +#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1) + +#undef __sockaddr +#define __sockaddr(field, len) __dynamic_array(u8, field, len) + +#undef __rel_dynamic_array +#define __rel_dynamic_array(type, item, len) u32 item; + +#undef __rel_string +#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) + +#undef __rel_string_len +#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) + +#undef __rel_bitmask +#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, -1) + +#undef __rel_sockaddr +#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) diff --git a/include/trace/stages/stage3_defines.h b/include/trace/stages/stage3_defines.h new file mode 100644 index 0000000..e3b183e --- /dev/null +++ b/include/trace/stages/stage3_defines.h @@ -0,0 +1,135 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 3 definitions for creating trace events */ + +#undef __entry +#define __entry field + +#undef TP_printk +#define TP_printk(fmt, args...) fmt "\n", args + +#undef __get_dynamic_array +#define __get_dynamic_array(field) \ + ((void *)__entry + (__entry->__data_loc_##field & 0xffff)) + +#undef __get_dynamic_array_len +#define __get_dynamic_array_len(field) \ + ((__entry->__data_loc_##field >> 16) & 0xffff) + +#undef __get_str +#define __get_str(field) ((char *)__get_dynamic_array(field)) + +#undef __get_rel_dynamic_array +#define __get_rel_dynamic_array(field) \ + ((void *)__entry + \ + offsetof(typeof(*__entry), __rel_loc_##field) + \ + sizeof(__entry->__rel_loc_##field) + \ + (__entry->__rel_loc_##field & 0xffff)) + +#undef __get_rel_dynamic_array_len +#define __get_rel_dynamic_array_len(field) \ + ((__entry->__rel_loc_##field >> 16) & 0xffff) + +#undef __get_rel_str +#define __get_rel_str(field) ((char *)__get_rel_dynamic_array(field)) + +#undef __get_bitmask +#define __get_bitmask(field) \ + ({ \ + void *__bitmask = __get_dynamic_array(field); \ + unsigned int __bitmask_size; \ + __bitmask_size = __get_dynamic_array_len(field); \ + trace_print_bitmask_seq(p, __bitmask, __bitmask_size); \ + }) + +#undef __get_rel_bitmask +#define __get_rel_bitmask(field) \ + ({ \ + void *__bitmask = __get_rel_dynamic_array(field); \ + unsigned int __bitmask_size; \ + __bitmask_size = __get_rel_dynamic_array_len(field); \ + trace_print_bitmask_seq(p, __bitmask, __bitmask_size); \ + }) + +#undef __get_sockaddr +#define __get_sockaddr(field) ((struct sockaddr *)__get_dynamic_array(field)) + +#undef __get_rel_sockaddr +#define __get_rel_sockaddr(field) ((struct sockaddr *)__get_rel_dynamic_array(field)) + +#undef __print_flags +#define __print_flags(flag, delim, flag_array...) \ + ({ \ + static const struct trace_print_flags __flags[] = \ + { flag_array, { -1, NULL }}; \ + trace_print_flags_seq(p, delim, flag, __flags); \ + }) + +#undef __print_symbolic +#define __print_symbolic(value, symbol_array...) \ + ({ \ + static const struct trace_print_flags symbols[] = \ + { symbol_array, { -1, NULL }}; \ + trace_print_symbols_seq(p, value, symbols); \ + }) + +#undef __print_flags_u64 +#undef __print_symbolic_u64 +#if BITS_PER_LONG == 32 +#define __print_flags_u64(flag, delim, flag_array...) \ + ({ \ + static const struct trace_print_flags_u64 __flags[] = \ + { flag_array, { -1, NULL } }; \ + trace_print_flags_seq_u64(p, delim, flag, __flags); \ + }) + +#define __print_symbolic_u64(value, symbol_array...) \ + ({ \ + static const struct trace_print_flags_u64 symbols[] = \ + { symbol_array, { -1, NULL } }; \ + trace_print_symbols_seq_u64(p, value, symbols); \ + }) +#else +#define __print_flags_u64(flag, delim, flag_array...) \ + __print_flags(flag, delim, flag_array) + +#define __print_symbolic_u64(value, symbol_array...) \ + __print_symbolic(value, symbol_array) +#endif + +#undef __print_hex +#define __print_hex(buf, buf_len) \ + trace_print_hex_seq(p, buf, buf_len, false) + +#undef __print_hex_str +#define __print_hex_str(buf, buf_len) \ + trace_print_hex_seq(p, buf, buf_len, true) + +#undef __print_array +#define __print_array(array, count, el_size) \ + ({ \ + BUILD_BUG_ON(el_size != 1 && el_size != 2 && \ + el_size != 4 && el_size != 8); \ + trace_print_array_seq(p, array, count, el_size); \ + }) + +#undef __print_hex_dump +#define __print_hex_dump(prefix_str, prefix_type, \ + rowsize, groupsize, buf, len, ascii) \ + trace_print_hex_dump_seq(p, prefix_str, prefix_type, \ + rowsize, groupsize, buf, len, ascii) + +#undef __print_ns_to_secs +#define __print_ns_to_secs(value) \ + ({ \ + u64 ____val = (u64)(value); \ + do_div(____val, NSEC_PER_SEC); \ + ____val; \ + }) + +#undef __print_ns_without_secs +#define __print_ns_without_secs(value) \ + ({ \ + u64 ____val = (u64)(value); \ + (u32) do_div(____val, NSEC_PER_SEC); \ + }) diff --git a/include/trace/stages/stage4_defines.h b/include/trace/stages/stage4_defines.h new file mode 100644 index 0000000..e80cdc3 --- /dev/null +++ b/include/trace/stages/stage4_defines.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 4 definitions for creating trace events */ + +#undef __field_ext +#define __field_ext(_type, _item, _filter_type) { \ + .type = #_type, .name = #_item, \ + .size = sizeof(_type), .align = __alignof__(_type), \ + .is_signed = is_signed_type(_type), .filter_type = _filter_type }, + +#undef __field_struct_ext +#define __field_struct_ext(_type, _item, _filter_type) { \ + .type = #_type, .name = #_item, \ + .size = sizeof(_type), .align = __alignof__(_type), \ + 0, .filter_type = _filter_type }, + +#undef __field +#define __field(type, item) __field_ext(type, item, FILTER_OTHER) + +#undef __field_struct +#define __field_struct(type, item) __field_struct_ext(type, item, FILTER_OTHER) + +#undef __array +#define __array(_type, _item, _len) { \ + .type = #_type"["__stringify(_len)"]", .name = #_item, \ + .size = sizeof(_type[_len]), .align = __alignof__(_type), \ + .is_signed = is_signed_type(_type), .filter_type = FILTER_OTHER }, + +#undef __dynamic_array +#define __dynamic_array(_type, _item, _len) { \ + .type = "__data_loc " #_type "[]", .name = #_item, \ + .size = 4, .align = 4, \ + .is_signed = is_signed_type(_type), .filter_type = FILTER_OTHER }, + +#undef __string +#define __string(item, src) __dynamic_array(char, item, -1) + +#undef __string_len +#define __string_len(item, src, len) __dynamic_array(char, item, -1) + +#undef __bitmask +#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1) + +#undef __sockaddr +#define __sockaddr(field, len) __dynamic_array(u8, field, len) + +#undef __rel_dynamic_array +#define __rel_dynamic_array(_type, _item, _len) { \ + .type = "__rel_loc " #_type "[]", .name = #_item, \ + .size = 4, .align = 4, \ + .is_signed = is_signed_type(_type), .filter_type = FILTER_OTHER }, + +#undef __rel_string +#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) + +#undef __rel_string_len +#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) + +#undef __rel_bitmask +#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, -1) + +#undef __rel_sockaddr +#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) diff --git a/include/trace/stages/stage5_defines.h b/include/trace/stages/stage5_defines.h new file mode 100644 index 0000000..7ee5931 --- /dev/null +++ b/include/trace/stages/stage5_defines.h @@ -0,0 +1,89 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 5 definitions for creating trace events */ + +/* + * remember the offset of each array from the beginning of the event. + */ + +#undef __entry +#define __entry entry + +#undef __field +#define __field(type, item) + +#undef __field_ext +#define __field_ext(type, item, filter_type) + +#undef __field_struct +#define __field_struct(type, item) + +#undef __field_struct_ext +#define __field_struct_ext(type, item, filter_type) + +#undef __array +#define __array(type, item, len) + +#undef __dynamic_array +#define __dynamic_array(type, item, len) \ + __item_length = (len) * sizeof(type); \ + __data_offsets->item = __data_size + \ + offsetof(typeof(*entry), __data); \ + __data_offsets->item |= __item_length << 16; \ + __data_size += __item_length; + +#undef __string +#define __string(item, src) __dynamic_array(char, item, \ + strlen((src) ? (const char *)(src) : "(null)") + 1) + +#undef __string_len +#define __string_len(item, src, len) __dynamic_array(char, item, (len) + 1) + +#undef __rel_dynamic_array +#define __rel_dynamic_array(type, item, len) \ + __item_length = (len) * sizeof(type); \ + __data_offsets->item = __data_size + \ + offsetof(typeof(*entry), __data) - \ + offsetof(typeof(*entry), __rel_loc_##item) - \ + sizeof(u32); \ + __data_offsets->item |= __item_length << 16; \ + __data_size += __item_length; + +#undef __rel_string +#define __rel_string(item, src) __rel_dynamic_array(char, item, \ + strlen((src) ? (const char *)(src) : "(null)") + 1) + +#undef __rel_string_len +#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, (len) + 1) +/* + * __bitmask_size_in_bytes_raw is the number of bytes needed to hold + * num_possible_cpus(). + */ +#define __bitmask_size_in_bytes_raw(nr_bits) \ + (((nr_bits) + 7) / 8) + +#define __bitmask_size_in_longs(nr_bits) \ + ((__bitmask_size_in_bytes_raw(nr_bits) + \ + ((BITS_PER_LONG / 8) - 1)) / (BITS_PER_LONG / 8)) + +/* + * __bitmask_size_in_bytes is the number of bytes needed to hold + * num_possible_cpus() padded out to the nearest long. This is what + * is saved in the buffer, just to be consistent. + */ +#define __bitmask_size_in_bytes(nr_bits) \ + (__bitmask_size_in_longs(nr_bits) * (BITS_PER_LONG / 8)) + +#undef __bitmask +#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, \ + __bitmask_size_in_longs(nr_bits)) + +#undef __rel_bitmask +#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, \ + __bitmask_size_in_longs(nr_bits)) + +#undef __sockaddr +#define __sockaddr(field, len) __dynamic_array(u8, field, len) + +#undef __rel_sockaddr +#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) diff --git a/include/trace/stages/stage6_defines.h b/include/trace/stages/stage6_defines.h new file mode 100644 index 0000000..e1724f7 --- /dev/null +++ b/include/trace/stages/stage6_defines.h @@ -0,0 +1,106 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 6 definitions for creating trace events */ + +#undef __entry +#define __entry entry + +#undef __field +#define __field(type, item) + +#undef __field_struct +#define __field_struct(type, item) + +#undef __array +#define __array(type, item, len) + +#undef __dynamic_array +#define __dynamic_array(type, item, len) \ + __entry->__data_loc_##item = __data_offsets.item; + +#undef __string +#define __string(item, src) __dynamic_array(char, item, -1) + +#undef __string_len +#define __string_len(item, src, len) __dynamic_array(char, item, -1) + +#undef __assign_str +#define __assign_str(dst, src) \ + strcpy(__get_str(dst), (src) ? (const char *)(src) : "(null)"); + +#undef __assign_str_len +#define __assign_str_len(dst, src, len) \ + do { \ + memcpy(__get_str(dst), (src), (len)); \ + __get_str(dst)[len] = '\0'; \ + } while(0) + +#undef __bitmask +#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1) + +#undef __get_bitmask +#define __get_bitmask(field) (char *)__get_dynamic_array(field) + +#undef __assign_bitmask +#define __assign_bitmask(dst, src, nr_bits) \ + memcpy(__get_bitmask(dst), (src), __bitmask_size_in_bytes(nr_bits)) + +#undef __sockaddr +#define __sockaddr(field, len) __dynamic_array(u8, field, len) + +#undef __get_sockaddr +#define __get_sockaddr(field) ((struct sockaddr *)__get_dynamic_array(field)) + +#undef __assign_sockaddr +#define __assign_sockaddr(dest, src, len) \ + memcpy(__get_dynamic_array(dest), src, len) + +#undef __rel_dynamic_array +#define __rel_dynamic_array(type, item, len) \ + __entry->__rel_loc_##item = __data_offsets.item; + +#undef __rel_string +#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) + +#undef __rel_string_len +#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) + +#undef __assign_rel_str +#define __assign_rel_str(dst, src) \ + strcpy(__get_rel_str(dst), (src) ? (const char *)(src) : "(null)"); + +#undef __assign_rel_str_len +#define __assign_rel_str_len(dst, src, len) \ + do { \ + memcpy(__get_rel_str(dst), (src), (len)); \ + __get_rel_str(dst)[len] = '\0'; \ + } while (0) + +#undef __rel_bitmask +#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, -1) + +#undef __get_rel_bitmask +#define __get_rel_bitmask(field) (char *)__get_rel_dynamic_array(field) + +#undef __assign_rel_bitmask +#define __assign_rel_bitmask(dst, src, nr_bits) \ + memcpy(__get_rel_bitmask(dst), (src), __bitmask_size_in_bytes(nr_bits)) + +#undef __rel_sockaddr +#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) + +#undef __get_rel_sockaddr +#define __get_rel_sockaddr(field) ((struct sockaddr *)__get_rel_dynamic_array(field)) + +#undef __assign_rel_sockaddr +#define __assign_rel_sockaddr(dest, src, len) \ + memcpy(__get_rel_dynamic_array(dest), src, len) + +#undef TP_fast_assign +#define TP_fast_assign(args...) args + +#undef __perf_count +#define __perf_count(c) (c) + +#undef __perf_task +#define __perf_task(t) (t) diff --git a/include/trace/stages/stage7_defines.h b/include/trace/stages/stage7_defines.h new file mode 100644 index 0000000..8a7ec24 --- /dev/null +++ b/include/trace/stages/stage7_defines.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Stage 7 definitions for creating trace events */ + +#undef __entry +#define __entry REC + +#undef __print_flags +#undef __print_symbolic +#undef __print_hex +#undef __print_hex_str +#undef __get_dynamic_array +#undef __get_dynamic_array_len +#undef __get_str +#undef __get_bitmask +#undef __get_sockaddr +#undef __get_rel_dynamic_array +#undef __get_rel_dynamic_array_len +#undef __get_rel_str +#undef __get_rel_bitmask +#undef __get_rel_sockaddr +#undef __print_array +#undef __print_hex_dump + +/* + * The below is not executed in the kernel. It is only what is + * displayed in the print format for userspace to parse. + */ +#undef __print_ns_to_secs +#define __print_ns_to_secs(val) (val) / 1000000000UL + +#undef __print_ns_without_secs +#define __print_ns_without_secs(val) (val) % 1000000000UL + +#undef TP_printk +#define TP_printk(fmt, args...) "\"" fmt "\", " __stringify(args) diff --git a/include/trace/trace_custom_events.h b/include/trace/trace_custom_events.h new file mode 100644 index 0000000..b567c72 --- /dev/null +++ b/include/trace/trace_custom_events.h @@ -0,0 +1,221 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * This is similar to the trace_events.h file, but is to only + * create custom trace events to be attached to existing tracepoints. + * Where as the TRACE_EVENT() macro (from trace_events.h) will create + * both the trace event and the tracepoint it will attach the event to, + * TRACE_CUSTOM_EVENT() is to create only a custom version of an existing + * trace event (created by TRACE_EVENT() or DEFINE_EVENT()), and will + * be placed in the "custom" system. + */ + +#include + +/* All custom events are placed in the custom group */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM custom + +#ifndef TRACE_SYSTEM_VAR +#define TRACE_SYSTEM_VAR TRACE_SYSTEM +#endif + +/* The init stage creates the system string and enum mappings */ + +#include "stages/init.h" + +#undef TRACE_CUSTOM_EVENT +#define TRACE_CUSTOM_EVENT(name, proto, args, tstruct, assign, print) \ + DECLARE_CUSTOM_EVENT_CLASS(name, \ + PARAMS(proto), \ + PARAMS(args), \ + PARAMS(tstruct), \ + PARAMS(assign), \ + PARAMS(print)); \ + DEFINE_CUSTOM_EVENT(name, name, PARAMS(proto), PARAMS(args)); + +/* Stage 1 creates the structure of the recorded event layout */ + +#include "stages/stage1_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print) \ + struct trace_custom_event_raw_##name { \ + struct trace_entry ent; \ + tstruct \ + char __data[]; \ + }; \ + \ + static struct trace_event_class custom_event_class_##name; + +#undef DEFINE_CUSTOM_EVENT +#define DEFINE_CUSTOM_EVENT(template, name, proto, args) \ + static struct trace_event_call __used \ + __attribute__((__aligned__(4))) custom_event_##name + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +/* Stage 2 creates the custom class */ + +#include "stages/stage2_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ + struct trace_custom_event_data_offsets_##call { \ + tstruct; \ + }; + +#undef DEFINE_CUSTOM_EVENT +#define DEFINE_CUSTOM_EVENT(template, name, proto, args) + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +/* Stage 3 create the way to print the custom event */ + +#include "stages/stage3_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ +static notrace enum print_line_t \ +trace_custom_raw_output_##call(struct trace_iterator *iter, int flags, \ + struct trace_event *trace_event) \ +{ \ + struct trace_seq *s = &iter->seq; \ + struct trace_seq __maybe_unused *p = &iter->tmp_seq; \ + struct trace_custom_event_raw_##call *field; \ + int ret; \ + \ + field = (typeof(field))iter->ent; \ + \ + ret = trace_raw_output_prep(iter, trace_event); \ + if (ret != TRACE_TYPE_HANDLED) \ + return ret; \ + \ + trace_event_printf(iter, print); \ + \ + return trace_handle_return(s); \ +} \ +static struct trace_event_functions trace_custom_event_type_funcs_##call = { \ + .trace = trace_custom_raw_output_##call, \ +}; + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +/* Stage 4 creates the offset layout for the fields */ + +#include "stages/stage4_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, func, print) \ +static struct trace_event_fields trace_custom_event_fields_##call[] = { \ + tstruct \ + {} }; + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +/* Stage 5 creates the helper function for dynamic fields */ + +#include "stages/stage5_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ +static inline notrace int trace_custom_event_get_offsets_##call( \ + struct trace_custom_event_data_offsets_##call *__data_offsets, proto) \ +{ \ + int __data_size = 0; \ + int __maybe_unused __item_length; \ + struct trace_custom_event_raw_##call __maybe_unused *entry; \ + \ + tstruct; \ + \ + return __data_size; \ +} + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +/* Stage 6 creates the probe function that records the event */ + +#include "stages/stage6_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ + \ +static notrace void \ +trace_custom_event_raw_event_##call(void *__data, proto) \ +{ \ + struct trace_event_file *trace_file = __data; \ + struct trace_custom_event_data_offsets_##call __maybe_unused __data_offsets; \ + struct trace_event_buffer fbuffer; \ + struct trace_custom_event_raw_##call *entry; \ + int __data_size; \ + \ + if (trace_trigger_soft_disabled(trace_file)) \ + return; \ + \ + __data_size = trace_custom_event_get_offsets_##call(&__data_offsets, args); \ + \ + entry = trace_event_buffer_reserve(&fbuffer, trace_file, \ + sizeof(*entry) + __data_size); \ + \ + if (!entry) \ + return; \ + \ + tstruct \ + \ + { assign; } \ + \ + trace_event_buffer_commit(&fbuffer); \ +} +/* + * The ftrace_test_custom_probe is compiled out, it is only here as a build time check + * to make sure that if the tracepoint handling changes, the ftrace probe will + * fail to compile unless it too is updated. + */ + +#undef DEFINE_CUSTOM_EVENT +#define DEFINE_CUSTOM_EVENT(template, call, proto, args) \ +static inline void ftrace_test_custom_probe_##call(void) \ +{ \ + check_trace_callback_type_##call(trace_custom_event_raw_event_##template); \ +} + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) + +/* Stage 7 creates the actual class and event structure for the custom event */ + +#include "stages/stage7_defines.h" + +#undef DECLARE_CUSTOM_EVENT_CLASS +#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ +static char custom_print_fmt_##call[] = print; \ +static struct trace_event_class __used __refdata custom_event_class_##call = { \ + .system = TRACE_SYSTEM_STRING, \ + .fields_array = trace_custom_event_fields_##call, \ + .fields = LIST_HEAD_INIT(custom_event_class_##call.fields),\ + .raw_init = trace_event_raw_init, \ + .probe = trace_custom_event_raw_event_##call, \ + .reg = trace_event_reg, \ +}; + +#undef DEFINE_CUSTOM_EVENT +#define DEFINE_CUSTOM_EVENT(template, call, proto, args) \ + \ +static struct trace_event_call __used custom_event_##call = { \ + .name = #call, \ + .class = &custom_event_class_##template, \ + .event.funcs = &trace_custom_event_type_funcs_##template, \ + .print_fmt = custom_print_fmt_##template, \ + .flags = TRACE_EVENT_FL_CUSTOM, \ +}; \ +static inline int trace_custom_event_##call##_update(struct tracepoint *tp) \ +{ \ + if (tp->name && strcmp(tp->name, #call) == 0) { \ + custom_event_##call.tp = tp; \ + custom_event_##call.flags = TRACE_EVENT_FL_TRACEPOINT; \ + return 1; \ + } \ + return 0; \ +} \ +static struct trace_event_call __used \ +__section("_ftrace_events") *__custom_event_##call = &custom_event_##call + +#include TRACE_INCLUDE(TRACE_INCLUDE_FILE) diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h index 7c86cc5..8a8cd66 100644 --- a/include/trace/trace_events.h +++ b/include/trace/trace_events.h @@ -24,42 +24,7 @@ #define TRACE_SYSTEM_VAR TRACE_SYSTEM #endif -#define __app__(x, y) str__##x##y -#define __app(x, y) __app__(x, y) - -#define TRACE_SYSTEM_STRING __app(TRACE_SYSTEM_VAR,__trace_system_name) - -#define TRACE_MAKE_SYSTEM_STR() \ - static const char TRACE_SYSTEM_STRING[] = \ - __stringify(TRACE_SYSTEM) - -TRACE_MAKE_SYSTEM_STR(); - -#undef TRACE_DEFINE_ENUM -#define TRACE_DEFINE_ENUM(a) \ - static struct trace_eval_map __used __initdata \ - __##TRACE_SYSTEM##_##a = \ - { \ - .system = TRACE_SYSTEM_STRING, \ - .eval_string = #a, \ - .eval_value = a \ - }; \ - static struct trace_eval_map __used \ - __section("_ftrace_eval_map") \ - *TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a - -#undef TRACE_DEFINE_SIZEOF -#define TRACE_DEFINE_SIZEOF(a) \ - static struct trace_eval_map __used __initdata \ - __##TRACE_SYSTEM##_##a = \ - { \ - .system = TRACE_SYSTEM_STRING, \ - .eval_string = "sizeof(" #a ")", \ - .eval_value = sizeof(a) \ - }; \ - static struct trace_eval_map __used \ - __section("_ftrace_eval_map") \ - *TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a +#include "stages/init.h" /* * DECLARE_EVENT_CLASS can be used to add a generic function @@ -80,54 +45,7 @@ TRACE_MAKE_SYSTEM_STR(); PARAMS(print)); \ DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args)); - -#undef __field -#define __field(type, item) type item; - -#undef __field_ext -#define __field_ext(type, item, filter_type) type item; - -#undef __field_struct -#define __field_struct(type, item) type item; - -#undef __field_struct_ext -#define __field_struct_ext(type, item, filter_type) type item; - -#undef __array -#define __array(type, item, len) type item[len]; - -#undef __dynamic_array -#define __dynamic_array(type, item, len) u32 __data_loc_##item; - -#undef __string -#define __string(item, src) __dynamic_array(char, item, -1) - -#undef __string_len -#define __string_len(item, src, len) __dynamic_array(char, item, -1) - -#undef __bitmask -#define __bitmask(item, nr_bits) __dynamic_array(char, item, -1) - -#undef __sockaddr -#define __sockaddr(field, len) __dynamic_array(u8, field, len) - -#undef __rel_dynamic_array -#define __rel_dynamic_array(type, item, len) u32 __rel_loc_##item; - -#undef __rel_string -#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) - -#undef __rel_string_len -#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) - -#undef __rel_bitmask -#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(char, item, -1) - -#undef __rel_sockaddr -#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) - -#undef TP_STRUCT__entry -#define TP_STRUCT__entry(args...) args +#include "stages/stage1_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print) \ @@ -191,56 +109,7 @@ TRACE_MAKE_SYSTEM_STR(); * The size of an array is also encoded, in the higher 16 bits of . */ -#undef TRACE_DEFINE_ENUM -#define TRACE_DEFINE_ENUM(a) - -#undef TRACE_DEFINE_SIZEOF -#define TRACE_DEFINE_SIZEOF(a) - -#undef __field -#define __field(type, item) - -#undef __field_ext -#define __field_ext(type, item, filter_type) - -#undef __field_struct -#define __field_struct(type, item) - -#undef __field_struct_ext -#define __field_struct_ext(type, item, filter_type) - -#undef __array -#define __array(type, item, len) - -#undef __dynamic_array -#define __dynamic_array(type, item, len) u32 item; - -#undef __string -#define __string(item, src) __dynamic_array(char, item, -1) - -#undef __string_len -#define __string_len(item, src, len) __dynamic_array(char, item, -1) - -#undef __bitmask -#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1) - -#undef __sockaddr -#define __sockaddr(field, len) __dynamic_array(u8, field, len) - -#undef __rel_dynamic_array -#define __rel_dynamic_array(type, item, len) u32 item; - -#undef __rel_string -#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) - -#undef __rel_string_len -#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) - -#undef __rel_bitmask -#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, -1) - -#undef __rel_sockaddr -#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) +#include "stages/stage2_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ @@ -312,137 +181,7 @@ TRACE_MAKE_SYSTEM_STR(); * in binary. */ -#undef __entry -#define __entry field - -#undef TP_printk -#define TP_printk(fmt, args...) fmt "\n", args - -#undef __get_dynamic_array -#define __get_dynamic_array(field) \ - ((void *)__entry + (__entry->__data_loc_##field & 0xffff)) - -#undef __get_dynamic_array_len -#define __get_dynamic_array_len(field) \ - ((__entry->__data_loc_##field >> 16) & 0xffff) - -#undef __get_str -#define __get_str(field) ((char *)__get_dynamic_array(field)) - -#undef __get_rel_dynamic_array -#define __get_rel_dynamic_array(field) \ - ((void *)__entry + \ - offsetof(typeof(*__entry), __rel_loc_##field) + \ - sizeof(__entry->__rel_loc_##field) + \ - (__entry->__rel_loc_##field & 0xffff)) - -#undef __get_rel_dynamic_array_len -#define __get_rel_dynamic_array_len(field) \ - ((__entry->__rel_loc_##field >> 16) & 0xffff) - -#undef __get_rel_str -#define __get_rel_str(field) ((char *)__get_rel_dynamic_array(field)) - -#undef __get_bitmask -#define __get_bitmask(field) \ - ({ \ - void *__bitmask = __get_dynamic_array(field); \ - unsigned int __bitmask_size; \ - __bitmask_size = __get_dynamic_array_len(field); \ - trace_print_bitmask_seq(p, __bitmask, __bitmask_size); \ - }) - -#undef __get_rel_bitmask -#define __get_rel_bitmask(field) \ - ({ \ - void *__bitmask = __get_rel_dynamic_array(field); \ - unsigned int __bitmask_size; \ - __bitmask_size = __get_rel_dynamic_array_len(field); \ - trace_print_bitmask_seq(p, __bitmask, __bitmask_size); \ - }) - -#undef __get_sockaddr -#define __get_sockaddr(field) ((struct sockaddr *)__get_dynamic_array(field)) - -#undef __get_rel_sockaddr -#define __get_rel_sockaddr(field) ((struct sockaddr *)__get_rel_dynamic_array(field)) - -#undef __print_flags -#define __print_flags(flag, delim, flag_array...) \ - ({ \ - static const struct trace_print_flags __flags[] = \ - { flag_array, { -1, NULL }}; \ - trace_print_flags_seq(p, delim, flag, __flags); \ - }) - -#undef __print_symbolic -#define __print_symbolic(value, symbol_array...) \ - ({ \ - static const struct trace_print_flags symbols[] = \ - { symbol_array, { -1, NULL }}; \ - trace_print_symbols_seq(p, value, symbols); \ - }) - -#undef __print_flags_u64 -#undef __print_symbolic_u64 -#if BITS_PER_LONG == 32 -#define __print_flags_u64(flag, delim, flag_array...) \ - ({ \ - static const struct trace_print_flags_u64 __flags[] = \ - { flag_array, { -1, NULL } }; \ - trace_print_flags_seq_u64(p, delim, flag, __flags); \ - }) - -#define __print_symbolic_u64(value, symbol_array...) \ - ({ \ - static const struct trace_print_flags_u64 symbols[] = \ - { symbol_array, { -1, NULL } }; \ - trace_print_symbols_seq_u64(p, value, symbols); \ - }) -#else -#define __print_flags_u64(flag, delim, flag_array...) \ - __print_flags(flag, delim, flag_array) - -#define __print_symbolic_u64(value, symbol_array...) \ - __print_symbolic(value, symbol_array) -#endif - -#undef __print_hex -#define __print_hex(buf, buf_len) \ - trace_print_hex_seq(p, buf, buf_len, false) - -#undef __print_hex_str -#define __print_hex_str(buf, buf_len) \ - trace_print_hex_seq(p, buf, buf_len, true) - -#undef __print_array -#define __print_array(array, count, el_size) \ - ({ \ - BUILD_BUG_ON(el_size != 1 && el_size != 2 && \ - el_size != 4 && el_size != 8); \ - trace_print_array_seq(p, array, count, el_size); \ - }) - -#undef __print_hex_dump -#define __print_hex_dump(prefix_str, prefix_type, \ - rowsize, groupsize, buf, len, ascii) \ - trace_print_hex_dump_seq(p, prefix_str, prefix_type, \ - rowsize, groupsize, buf, len, ascii) - -#undef __print_ns_to_secs -#define __print_ns_to_secs(value) \ - ({ \ - u64 ____val = (u64)(value); \ - do_div(____val, NSEC_PER_SEC); \ - ____val; \ - }) - -#undef __print_ns_without_secs -#define __print_ns_without_secs(value) \ - ({ \ - u64 ____val = (u64)(value); \ - (u32) do_div(____val, NSEC_PER_SEC); \ - }) +#include "stages/stage3_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ @@ -497,65 +236,7 @@ static struct trace_event_functions trace_event_type_funcs_##call = { \ #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) -#undef __field_ext -#define __field_ext(_type, _item, _filter_type) { \ - .type = #_type, .name = #_item, \ - .size = sizeof(_type), .align = __alignof__(_type), \ - .is_signed = is_signed_type(_type), .filter_type = _filter_type }, - -#undef __field_struct_ext -#define __field_struct_ext(_type, _item, _filter_type) { \ - .type = #_type, .name = #_item, \ - .size = sizeof(_type), .align = __alignof__(_type), \ - 0, .filter_type = _filter_type }, - -#undef __field -#define __field(type, item) __field_ext(type, item, FILTER_OTHER) - -#undef __field_struct -#define __field_struct(type, item) __field_struct_ext(type, item, FILTER_OTHER) - -#undef __array -#define __array(_type, _item, _len) { \ - .type = #_type"["__stringify(_len)"]", .name = #_item, \ - .size = sizeof(_type[_len]), .align = __alignof__(_type), \ - .is_signed = is_signed_type(_type), .filter_type = FILTER_OTHER }, - -#undef __dynamic_array -#define __dynamic_array(_type, _item, _len) { \ - .type = "__data_loc " #_type "[]", .name = #_item, \ - .size = 4, .align = 4, \ - .is_signed = is_signed_type(_type), .filter_type = FILTER_OTHER }, - -#undef __string -#define __string(item, src) __dynamic_array(char, item, -1) - -#undef __string_len -#define __string_len(item, src, len) __dynamic_array(char, item, -1) - -#undef __bitmask -#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1) - -#undef __sockaddr -#define __sockaddr(field, len) __dynamic_array(u8, field, len) - -#undef __rel_dynamic_array -#define __rel_dynamic_array(_type, _item, _len) { \ - .type = "__rel_loc " #_type "[]", .name = #_item, \ - .size = 4, .align = 4, \ - .is_signed = is_signed_type(_type), .filter_type = FILTER_OTHER }, - -#undef __rel_string -#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) - -#undef __rel_string_len -#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) - -#undef __rel_bitmask -#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, -1) - -#undef __rel_sockaddr -#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) +#include "stages/stage4_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, func, print) \ @@ -568,91 +249,7 @@ static struct trace_event_fields trace_event_fields_##call[] = { \ #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) -/* - * remember the offset of each array from the beginning of the event. - */ - -#undef __entry -#define __entry entry - -#undef __field -#define __field(type, item) - -#undef __field_ext -#define __field_ext(type, item, filter_type) - -#undef __field_struct -#define __field_struct(type, item) - -#undef __field_struct_ext -#define __field_struct_ext(type, item, filter_type) - -#undef __array -#define __array(type, item, len) - -#undef __dynamic_array -#define __dynamic_array(type, item, len) \ - __item_length = (len) * sizeof(type); \ - __data_offsets->item = __data_size + \ - offsetof(typeof(*entry), __data); \ - __data_offsets->item |= __item_length << 16; \ - __data_size += __item_length; - -#undef __string -#define __string(item, src) __dynamic_array(char, item, \ - strlen((src) ? (const char *)(src) : "(null)") + 1) - -#undef __string_len -#define __string_len(item, src, len) __dynamic_array(char, item, (len) + 1) - -#undef __rel_dynamic_array -#define __rel_dynamic_array(type, item, len) \ - __item_length = (len) * sizeof(type); \ - __data_offsets->item = __data_size + \ - offsetof(typeof(*entry), __data) - \ - offsetof(typeof(*entry), __rel_loc_##item) - \ - sizeof(u32); \ - __data_offsets->item |= __item_length << 16; \ - __data_size += __item_length; - -#undef __rel_string -#define __rel_string(item, src) __rel_dynamic_array(char, item, \ - strlen((src) ? (const char *)(src) : "(null)") + 1) - -#undef __rel_string_len -#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, (len) + 1) -/* - * __bitmask_size_in_bytes_raw is the number of bytes needed to hold - * num_possible_cpus(). - */ -#define __bitmask_size_in_bytes_raw(nr_bits) \ - (((nr_bits) + 7) / 8) - -#define __bitmask_size_in_longs(nr_bits) \ - ((__bitmask_size_in_bytes_raw(nr_bits) + \ - ((BITS_PER_LONG / 8) - 1)) / (BITS_PER_LONG / 8)) - -/* - * __bitmask_size_in_bytes is the number of bytes needed to hold - * num_possible_cpus() padded out to the nearest long. This is what - * is saved in the buffer, just to be consistent. - */ -#define __bitmask_size_in_bytes(nr_bits) \ - (__bitmask_size_in_longs(nr_bits) * (BITS_PER_LONG / 8)) - -#undef __bitmask -#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, \ - __bitmask_size_in_longs(nr_bits)) - -#undef __rel_bitmask -#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, \ - __bitmask_size_in_longs(nr_bits)) - -#undef __sockaddr -#define __sockaddr(field, len) __dynamic_array(u8, field, len) - -#undef __rel_sockaddr -#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) +#include "stages/stage5_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ @@ -775,107 +372,7 @@ static inline notrace int trace_event_get_offsets_##call( \ #define _TRACE_PERF_INIT(call) #endif /* CONFIG_PERF_EVENTS */ -#undef __entry -#define __entry entry - -#undef __field -#define __field(type, item) - -#undef __field_struct -#define __field_struct(type, item) - -#undef __array -#define __array(type, item, len) - -#undef __dynamic_array -#define __dynamic_array(type, item, len) \ - __entry->__data_loc_##item = __data_offsets.item; - -#undef __string -#define __string(item, src) __dynamic_array(char, item, -1) - -#undef __string_len -#define __string_len(item, src, len) __dynamic_array(char, item, -1) - -#undef __assign_str -#define __assign_str(dst, src) \ - strcpy(__get_str(dst), (src) ? (const char *)(src) : "(null)"); - -#undef __assign_str_len -#define __assign_str_len(dst, src, len) \ - do { \ - memcpy(__get_str(dst), (src), (len)); \ - __get_str(dst)[len] = '\0'; \ - } while(0) - -#undef __bitmask -#define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1) - -#undef __get_bitmask -#define __get_bitmask(field) (char *)__get_dynamic_array(field) - -#undef __assign_bitmask -#define __assign_bitmask(dst, src, nr_bits) \ - memcpy(__get_bitmask(dst), (src), __bitmask_size_in_bytes(nr_bits)) - -#undef __sockaddr -#define __sockaddr(field, len) __dynamic_array(u8, field, len) - -#undef __get_sockaddr -#define __get_sockaddr(field) ((struct sockaddr *)__get_dynamic_array(field)) - -#define __assign_sockaddr(dest, src, len) \ - memcpy(__get_dynamic_array(dest), src, len) - -#undef __rel_dynamic_array -#define __rel_dynamic_array(type, item, len) \ - __entry->__rel_loc_##item = __data_offsets.item; - -#undef __rel_string -#define __rel_string(item, src) __rel_dynamic_array(char, item, -1) - -#undef __rel_string_len -#define __rel_string_len(item, src, len) __rel_dynamic_array(char, item, -1) - -#undef __assign_rel_str -#define __assign_rel_str(dst, src) \ - strcpy(__get_rel_str(dst), (src) ? (const char *)(src) : "(null)"); - -#undef __assign_rel_str_len -#define __assign_rel_str_len(dst, src, len) \ - do { \ - memcpy(__get_rel_str(dst), (src), (len)); \ - __get_rel_str(dst)[len] = '\0'; \ - } while (0) - -#undef __rel_bitmask -#define __rel_bitmask(item, nr_bits) __rel_dynamic_array(unsigned long, item, -1) - -#undef __get_rel_bitmask -#define __get_rel_bitmask(field) (char *)__get_rel_dynamic_array(field) - -#undef __assign_rel_bitmask -#define __assign_rel_bitmask(dst, src, nr_bits) \ - memcpy(__get_rel_bitmask(dst), (src), __bitmask_size_in_bytes(nr_bits)) - -#undef __rel_sockaddr -#define __rel_sockaddr(field, len) __rel_dynamic_array(u8, field, len) - -#undef __get_rel_sockaddr -#define __get_rel_sockaddr(field) ((struct sockaddr *)__get_rel_dynamic_array(field)) - -#define __assign_rel_sockaddr(dest, src, len) \ - memcpy(__get_rel_dynamic_array(dest), src, len) - - -#undef TP_fast_assign -#define TP_fast_assign(args...) args - -#undef __perf_count -#define __perf_count(c) (c) - -#undef __perf_task -#define __perf_task(t) (t) +#include "stages/stage6_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ @@ -921,38 +418,7 @@ static inline void ftrace_test_probe_##call(void) \ #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) -#undef __entry -#define __entry REC - -#undef __print_flags -#undef __print_symbolic -#undef __print_hex -#undef __print_hex_str -#undef __get_dynamic_array -#undef __get_dynamic_array_len -#undef __get_str -#undef __get_bitmask -#undef __get_sockaddr -#undef __get_rel_dynamic_array -#undef __get_rel_dynamic_array_len -#undef __get_rel_str -#undef __get_rel_bitmask -#undef __get_rel_sockaddr -#undef __print_array -#undef __print_hex_dump - -/* - * The below is not executed in the kernel. It is only what is - * displayed in the print format for userspace to parse. - */ -#undef __print_ns_to_secs -#define __print_ns_to_secs(val) (val) / 1000000000UL - -#undef __print_ns_without_secs -#define __print_ns_without_secs(val) (val) % 1000000000UL - -#undef TP_printk -#define TP_printk(fmt, args...) "\"" fmt "\", " __stringify(args) +#include "stages/stage7_defines.h" #undef DECLARE_EVENT_CLASS #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \ diff --git a/include/uapi/linux/user_events.h b/include/uapi/linux/user_events.h new file mode 100644 index 0000000..e570840 --- /dev/null +++ b/include/uapi/linux/user_events.h @@ -0,0 +1,116 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Copyright (c) 2021, Microsoft Corporation. + * + * Authors: + * Beau Belgrave + */ +#ifndef _UAPI_LINUX_USER_EVENTS_H +#define _UAPI_LINUX_USER_EVENTS_H + +#include +#include + +#ifdef __KERNEL__ +#include +#else +#include +#endif + +#define USER_EVENTS_SYSTEM "user_events" +#define USER_EVENTS_PREFIX "u:" + +/* Bits 0-6 are for known probe types, Bit 7 is for unknown probes */ +#define EVENT_BIT_FTRACE 0 +#define EVENT_BIT_PERF 1 +#define EVENT_BIT_OTHER 7 + +#define EVENT_STATUS_FTRACE (1 << EVENT_BIT_FTRACE) +#define EVENT_STATUS_PERF (1 << EVENT_BIT_PERF) +#define EVENT_STATUS_OTHER (1 << EVENT_BIT_OTHER) + +/* Create dynamic location entry within a 32-bit value */ +#define DYN_LOC(offset, size) ((size) << 16 | (offset)) + +/* Use raw iterator for attached BPF program(s), no affect on ftrace/perf */ +#define FLAG_BPF_ITER (1 << 0) + +/* + * Describes an event registration and stores the results of the registration. + * This structure is passed to the DIAG_IOCSREG ioctl, callers at a minimum + * must set the size and name_args before invocation. + */ +struct user_reg { + + /* Input: Size of the user_reg structure being used */ + __u32 size; + + /* Input: Pointer to string with event name, description and flags */ + __u64 name_args; + + /* Output: Byte index of the event within the status page */ + __u32 status_index; + + /* Output: Index of the event to use when writing data */ + __u32 write_index; +}; + +#define DIAG_IOC_MAGIC '*' + +/* Requests to register a user_event */ +#define DIAG_IOCSREG _IOWR(DIAG_IOC_MAGIC, 0, struct user_reg*) + +/* Requests to delete a user_event */ +#define DIAG_IOCSDEL _IOW(DIAG_IOC_MAGIC, 1, char*) + +/* Data type that was passed to the BPF program */ +enum { + /* Data resides in kernel space */ + USER_BPF_DATA_KERNEL, + + /* Data resides in user space */ + USER_BPF_DATA_USER, + + /* Data is a pointer to a user_bpf_iter structure */ + USER_BPF_DATA_ITER, +}; + +/* + * Describes an iovec iterator that BPF programs can use to access data for + * a given user_event write() / writev() call. + */ +struct user_bpf_iter { + + /* Offset of the data within the first iovec */ + __u32 iov_offset; + + /* Number of iovec structures */ + __u32 nr_segs; + + /* Pointer to iovec structures */ + const struct iovec *iov; +}; + +/* Context that BPF programs receive when attached to a user_event */ +struct user_bpf_context { + + /* Data type being passed (see union below) */ + __u32 data_type; + + /* Length of the data */ + __u32 data_len; + + /* Pointer to data, varies by data type */ + union { + /* Kernel data (data_type == USER_BPF_DATA_KERNEL) */ + void *kdata; + + /* User data (data_type == USER_BPF_DATA_USER) */ + void *udata; + + /* Direct iovec (data_type == USER_BPF_DATA_ITER) */ + struct user_bpf_iter *iter; + }; +}; + +#endif /* _UAPI_LINUX_USER_EVENTS_H */ diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index a5eb5e7..16a52a7 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -737,6 +737,20 @@ config SYNTH_EVENTS If in doubt, say N. +config USER_EVENTS + bool "User trace events" + select TRACING + select DYNAMIC_EVENTS + help + User trace events are user-defined trace events that + can be used like an existing kernel trace event. User trace + events are generated by writing to a tracefs file. User + processes can determine if their tracing events should be + generated by memory mapping a tracefs file and checking for + an associated byte being non-zero. + + If in doubt, say N. + config HIST_TRIGGERS bool "Histogram triggers" depends on ARCH_HAVE_NMI_SAFE_CMPXCHG diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index bedc5ca..19ef375 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -82,6 +82,7 @@ obj-$(CONFIG_PROBE_EVENTS) += trace_eprobe.o obj-$(CONFIG_TRACE_EVENT_INJECT) += trace_events_inject.o obj-$(CONFIG_SYNTH_EVENTS) += trace_events_synth.o obj-$(CONFIG_HIST_TRIGGERS) += trace_events_hist.o +obj-$(CONFIG_USER_EVENTS) += trace_events_user.o obj-$(CONFIG_BPF_EVENTS) += bpf_trace.o obj-$(CONFIG_KPROBE_EVENTS) += trace_kprobe.o obj-$(CONFIG_TRACEPOINTS) += error_report-traces.o diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 8b568f5..e59d80c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7096,6 +7096,8 @@ void __init ftrace_free_init_mem(void) void *start = (void *)(&__init_begin); void *end = (void *)(&__init_end); + ftrace_boot_snapshot(); + ftrace_free_mem(NULL, start, end); } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index eb44418..08ea781 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -185,6 +185,7 @@ static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; static char *default_bootup_tracer; static bool allocate_snapshot; +static bool snapshot_at_boot; static int __init set_cmdline_ftrace(char *str) { @@ -230,6 +231,15 @@ static int __init boot_alloc_snapshot(char *str) __setup("alloc_snapshot", boot_alloc_snapshot); +static int __init boot_snapshot(char *str) +{ + snapshot_at_boot = true; + boot_alloc_snapshot(str); + return 1; +} +__setup("ftrace_boot_snapshot", boot_snapshot); + + static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; static int __init set_trace_boot_options(char *str) @@ -7725,7 +7735,7 @@ const struct file_operations trace_min_max_fops = { struct err_info { const char **errs; /* ptr to loc-specific array of err strings */ u8 type; /* index into errs -> specific err string */ - u8 pos; /* MAX_FILTER_STR_VAL = 256 */ + u16 pos; /* caret position */ u64 ts; }; @@ -7733,26 +7743,52 @@ struct tracing_log_err { struct list_head list; struct err_info info; char loc[TRACING_LOG_LOC_MAX]; /* err location */ - char cmd[MAX_FILTER_STR_VAL]; /* what caused err */ + char *cmd; /* what caused err */ }; static DEFINE_MUTEX(tracing_err_log_lock); -static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) +static struct tracing_log_err *alloc_tracing_log_err(int len) +{ + struct tracing_log_err *err; + + err = kzalloc(sizeof(*err), GFP_KERNEL); + if (!err) + return ERR_PTR(-ENOMEM); + + err->cmd = kzalloc(len, GFP_KERNEL); + if (!err->cmd) { + kfree(err); + return ERR_PTR(-ENOMEM); + } + + return err; +} + +static void free_tracing_log_err(struct tracing_log_err *err) +{ + kfree(err->cmd); + kfree(err); +} + +static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr, + int len) { struct tracing_log_err *err; if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) { - err = kzalloc(sizeof(*err), GFP_KERNEL); - if (!err) - err = ERR_PTR(-ENOMEM); - else + err = alloc_tracing_log_err(len); + if (PTR_ERR(err) != -ENOMEM) tr->n_err_log_entries++; return err; } err = list_first_entry(&tr->err_log, struct tracing_log_err, list); + kfree(err->cmd); + err->cmd = kzalloc(len, GFP_KERNEL); + if (!err->cmd) + return ERR_PTR(-ENOMEM); list_del(&err->list); return err; @@ -7813,22 +7849,25 @@ unsigned int err_pos(char *cmd, const char *str) */ void tracing_log_err(struct trace_array *tr, const char *loc, const char *cmd, - const char **errs, u8 type, u8 pos) + const char **errs, u8 type, u16 pos) { struct tracing_log_err *err; + int len = 0; if (!tr) tr = &global_trace; + len += sizeof(CMD_PREFIX) + 2 * sizeof("\n") + strlen(cmd) + 1; + mutex_lock(&tracing_err_log_lock); - err = get_tracing_log_err(tr); + err = get_tracing_log_err(tr, len); if (PTR_ERR(err) == -ENOMEM) { mutex_unlock(&tracing_err_log_lock); return; } snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc); - snprintf(err->cmd, MAX_FILTER_STR_VAL,"\n" CMD_PREFIX "%s\n", cmd); + snprintf(err->cmd, len, "\n" CMD_PREFIX "%s\n", cmd); err->info.errs = errs; err->info.type = type; @@ -7846,7 +7885,7 @@ static void clear_tracing_err_log(struct trace_array *tr) mutex_lock(&tracing_err_log_lock); list_for_each_entry_safe(err, next, &tr->err_log, list) { list_del(&err->list); - kfree(err); + free_tracing_log_err(err); } tr->n_err_log_entries = 0; @@ -7874,9 +7913,9 @@ static void tracing_err_log_seq_stop(struct seq_file *m, void *v) mutex_unlock(&tracing_err_log_lock); } -static void tracing_err_log_show_pos(struct seq_file *m, u8 pos) +static void tracing_err_log_show_pos(struct seq_file *m, u16 pos) { - u8 i; + u16 i; for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++) seq_putc(m, ' '); @@ -10122,6 +10161,14 @@ out: return ret; } +void __init ftrace_boot_snapshot(void) +{ + if (snapshot_at_boot) { + tracing_snapshot(); + internal_trace_puts("** Boot snapshot taken **\n"); + } +} + void __init early_trace_init(void) { if (tracepoint_printk) { diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index c5b09c3..07d9902 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1877,7 +1877,7 @@ extern ssize_t trace_parse_run_command(struct file *file, extern unsigned int err_pos(char *cmd, const char *str); extern void tracing_log_err(struct trace_array *tr, const char *loc, const char *cmd, - const char **errs, u8 type, u8 pos); + const char **errs, u8 type, u16 pos); /* * Normal trace_printk() and friends allocates special buffers diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index da69519..e11e167 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -40,6 +40,14 @@ static LIST_HEAD(ftrace_generic_fields); static LIST_HEAD(ftrace_common_fields); static bool eventdir_initialized; +static LIST_HEAD(module_strings); + +struct module_string { + struct list_head next; + struct module *module; + char *str; +}; + #define GFP_TRACE (GFP_KERNEL | __GFP_ZERO) static struct kmem_cache *field_cachep; @@ -2643,6 +2651,76 @@ static void update_event_printk(struct trace_event_call *call, } } +static void add_str_to_module(struct module *module, char *str) +{ + struct module_string *modstr; + + modstr = kmalloc(sizeof(*modstr), GFP_KERNEL); + + /* + * If we failed to allocate memory here, then we'll just + * let the str memory leak when the module is removed. + * If this fails to allocate, there's worse problems than + * a leaked string on module removal. + */ + if (WARN_ON_ONCE(!modstr)) + return; + + modstr->module = module; + modstr->str = str; + + list_add(&modstr->next, &module_strings); +} + +static void update_event_fields(struct trace_event_call *call, + struct trace_eval_map *map) +{ + struct ftrace_event_field *field; + struct list_head *head; + char *ptr; + char *str; + int len = strlen(map->eval_string); + + /* Dynamic events should never have field maps */ + if (WARN_ON_ONCE(call->flags & TRACE_EVENT_FL_DYNAMIC)) + return; + + head = trace_get_fields(call); + list_for_each_entry(field, head, link) { + ptr = strchr(field->type, '['); + if (!ptr) + continue; + ptr++; + + if (!isalpha(*ptr) && *ptr != '_') + continue; + + if (strncmp(map->eval_string, ptr, len) != 0) + continue; + + str = kstrdup(field->type, GFP_KERNEL); + if (WARN_ON_ONCE(!str)) + return; + ptr = str + (ptr - field->type); + ptr = eval_replace(ptr, map, len); + /* enum/sizeof string smaller than value */ + if (WARN_ON_ONCE(!ptr)) { + kfree(str); + continue; + } + + /* + * If the event is part of a module, then we need to free the string + * when the module is removed. Otherwise, it will stay allocated + * until a reboot. + */ + if (call->module) + add_str_to_module(call->module, str); + + field->type = str; + } +} + void trace_event_eval_update(struct trace_eval_map **map, int len) { struct trace_event_call *call, *p; @@ -2678,6 +2756,7 @@ void trace_event_eval_update(struct trace_eval_map **map, int len) first = false; } update_event_printk(call, map[i]); + update_event_fields(call, map[i]); } } } @@ -2768,6 +2847,7 @@ int trace_add_event_call(struct trace_event_call *call) mutex_unlock(&trace_types_lock); return ret; } +EXPORT_SYMBOL_GPL(trace_add_event_call); /* * Must be called under locking of trace_types_lock, event_mutex and @@ -2829,6 +2909,7 @@ int trace_remove_event_call(struct trace_event_call *call) return ret; } +EXPORT_SYMBOL_GPL(trace_remove_event_call); #define for_each_event(event, start, end) \ for (event = start; \ @@ -2863,6 +2944,7 @@ static void trace_module_add_events(struct module *mod) static void trace_module_remove_events(struct module *mod) { struct trace_event_call *call, *p; + struct module_string *modstr, *m; down_write(&trace_event_sem); list_for_each_entry_safe(call, p, &ftrace_events, list) { @@ -2871,6 +2953,14 @@ static void trace_module_remove_events(struct module *mod) if (call->module == mod) __trace_remove_event_call(call); } + /* Check for any strings allocade for this module */ + list_for_each_entry_safe(modstr, m, &module_strings, next) { + if (modstr->module != mod) + continue; + list_del(&modstr->next); + kfree(modstr->str); + kfree(modstr); + } up_write(&trace_event_sem); /* diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index dc7f733..44db5ba 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -727,11 +727,16 @@ static struct track_data *track_data_alloc(unsigned int key_len, return data; } -static char last_cmd[MAX_FILTER_STR_VAL]; +#define HIST_PREFIX "hist:" + +static char *last_cmd; static char last_cmd_loc[MAX_FILTER_STR_VAL]; static int errpos(char *str) { + if (!str || !last_cmd) + return 0; + return err_pos(last_cmd, str); } @@ -739,12 +744,22 @@ static void last_cmd_set(struct trace_event_file *file, char *str) { const char *system = NULL, *name = NULL; struct trace_event_call *call; + int len; if (!str) return; - strcpy(last_cmd, "hist:"); - strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); + /* sizeof() contains the nul byte */ + len = sizeof(HIST_PREFIX) + strlen(str); + kfree(last_cmd); + last_cmd = kzalloc(len, GFP_KERNEL); + if (!last_cmd) + return; + + strcpy(last_cmd, HIST_PREFIX); + /* Again, sizeof() contains the nul byte */ + len -= sizeof(HIST_PREFIX); + strncat(last_cmd, str, len); if (file) { call = file->event_call; @@ -757,18 +772,22 @@ static void last_cmd_set(struct trace_event_file *file, char *str) } if (system) - snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); + snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); } -static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) +static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) { + if (!last_cmd) + return; + tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, err_type, err_pos); } static void hist_err_clear(void) { - last_cmd[0] = '\0'; + if (last_cmd) + last_cmd[0] = '\0'; last_cmd_loc[0] = '\0'; } @@ -5610,7 +5629,7 @@ static int event_hist_trigger_print(struct seq_file *m, bool have_var = false; unsigned int i; - seq_puts(m, "hist:"); + seq_puts(m, HIST_PREFIX); if (data->name) seq_printf(m, "%s:", data->name); diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 154db74..5e8c07a 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -42,10 +42,13 @@ enum { ERRORS }; static const char *err_text[] = { ERRORS }; -static char last_cmd[MAX_FILTER_STR_VAL]; +static char *last_cmd; static int errpos(const char *str) { + if (!str || !last_cmd) + return 0; + return err_pos(last_cmd, str); } @@ -54,11 +57,16 @@ static void last_cmd_set(const char *str) if (!str) return; - strncpy(last_cmd, str, MAX_FILTER_STR_VAL - 1); + kfree(last_cmd); + + last_cmd = kstrdup(str, GFP_KERNEL); } -static void synth_err(u8 err_type, u8 err_pos) +static void synth_err(u8 err_type, u16 err_pos) { + if (!last_cmd) + return; + tracing_log_err(NULL, "synthetic_events", last_cmd, err_text, err_type, err_pos); } diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c new file mode 100644 index 0000000..8b3d241 --- /dev/null +++ b/kernel/trace/trace_events_user.c @@ -0,0 +1,1690 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2021, Microsoft Corporation. + * + * Authors: + * Beau Belgrave + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "trace.h" +#include "trace_dynevent.h" + +#define USER_EVENTS_PREFIX_LEN (sizeof(USER_EVENTS_PREFIX)-1) + +#define FIELD_DEPTH_TYPE 0 +#define FIELD_DEPTH_NAME 1 +#define FIELD_DEPTH_SIZE 2 + +/* + * Limits how many trace_event calls user processes can create: + * Must be a power of two of PAGE_SIZE. + */ +#define MAX_PAGE_ORDER 0 +#define MAX_PAGES (1 << MAX_PAGE_ORDER) +#define MAX_EVENTS (MAX_PAGES * PAGE_SIZE) + +/* Limit how long of an event name plus args within the subsystem. */ +#define MAX_EVENT_DESC 512 +#define EVENT_NAME(user_event) ((user_event)->tracepoint.name) +#define MAX_FIELD_ARRAY_SIZE 1024 +#define MAX_FIELD_ARG_NAME 256 + +#define MAX_BPF_COPY_SIZE PAGE_SIZE +#define MAX_STACK_BPF_DATA 512 + +static char *register_page_data; + +static DEFINE_MUTEX(reg_mutex); +static DEFINE_HASHTABLE(register_table, 4); +static DECLARE_BITMAP(page_bitmap, MAX_EVENTS); + +/* + * Stores per-event properties, as users register events + * within a file a user_event might be created if it does not + * already exist. These are globally used and their lifetime + * is tied to the refcnt member. These cannot go away until the + * refcnt reaches zero. + */ +struct user_event { + struct tracepoint tracepoint; + struct trace_event_call call; + struct trace_event_class class; + struct dyn_event devent; + struct hlist_node node; + struct list_head fields; + struct list_head validators; + atomic_t refcnt; + int index; + int flags; + int min_size; +}; + +/* + * Stores per-file events references, as users register events + * within a file this structure is modified and freed via RCU. + * The lifetime of this struct is tied to the lifetime of the file. + * These are not shared and only accessible by the file that created it. + */ +struct user_event_refs { + struct rcu_head rcu; + int count; + struct user_event *events[]; +}; + +#define VALIDATOR_ENSURE_NULL (1 << 0) +#define VALIDATOR_REL (1 << 1) + +struct user_event_validator { + struct list_head link; + int offset; + int flags; +}; + +typedef void (*user_event_func_t) (struct user_event *user, struct iov_iter *i, + void *tpdata, bool *faulted); + +static int user_event_parse(char *name, char *args, char *flags, + struct user_event **newuser); + +static u32 user_event_key(char *name) +{ + return jhash(name, strlen(name), 0); +} + +static __always_inline __must_check +size_t copy_nofault(void *addr, size_t bytes, struct iov_iter *i) +{ + size_t ret; + + pagefault_disable(); + + ret = copy_from_iter_nocache(addr, bytes, i); + + pagefault_enable(); + + return ret; +} + +static struct list_head *user_event_get_fields(struct trace_event_call *call) +{ + struct user_event *user = (struct user_event *)call->data; + + return &user->fields; +} + +/* + * Parses a register command for user_events + * Format: event_name[:FLAG1[,FLAG2...]] [field1[;field2...]] + * + * Example event named 'test' with a 20 char 'msg' field with an unsigned int + * 'id' field after: + * test char[20] msg;unsigned int id + * + * NOTE: Offsets are from the user data perspective, they are not from the + * trace_entry/buffer perspective. We automatically add the common properties + * sizes to the offset for the user. + * + * Upon success user_event has its ref count increased by 1. + */ +static int user_event_parse_cmd(char *raw_command, struct user_event **newuser) +{ + char *name = raw_command; + char *args = strpbrk(name, " "); + char *flags; + + if (args) + *args++ = '\0'; + + flags = strpbrk(name, ":"); + + if (flags) + *flags++ = '\0'; + + return user_event_parse(name, args, flags, newuser); +} + +static int user_field_array_size(const char *type) +{ + const char *start = strchr(type, '['); + char val[8]; + char *bracket; + int size = 0; + + if (start == NULL) + return -EINVAL; + + if (strscpy(val, start + 1, sizeof(val)) <= 0) + return -EINVAL; + + bracket = strchr(val, ']'); + + if (!bracket) + return -EINVAL; + + *bracket = '\0'; + + if (kstrtouint(val, 0, &size)) + return -EINVAL; + + if (size > MAX_FIELD_ARRAY_SIZE) + return -EINVAL; + + return size; +} + +static int user_field_size(const char *type) +{ + /* long is not allowed from a user, since it's ambigious in size */ + if (strcmp(type, "s64") == 0) + return sizeof(s64); + if (strcmp(type, "u64") == 0) + return sizeof(u64); + if (strcmp(type, "s32") == 0) + return sizeof(s32); + if (strcmp(type, "u32") == 0) + return sizeof(u32); + if (strcmp(type, "int") == 0) + return sizeof(int); + if (strcmp(type, "unsigned int") == 0) + return sizeof(unsigned int); + if (strcmp(type, "s16") == 0) + return sizeof(s16); + if (strcmp(type, "u16") == 0) + return sizeof(u16); + if (strcmp(type, "short") == 0) + return sizeof(short); + if (strcmp(type, "unsigned short") == 0) + return sizeof(unsigned short); + if (strcmp(type, "s8") == 0) + return sizeof(s8); + if (strcmp(type, "u8") == 0) + return sizeof(u8); + if (strcmp(type, "char") == 0) + return sizeof(char); + if (strcmp(type, "unsigned char") == 0) + return sizeof(unsigned char); + if (str_has_prefix(type, "char[")) + return user_field_array_size(type); + if (str_has_prefix(type, "unsigned char[")) + return user_field_array_size(type); + if (str_has_prefix(type, "__data_loc ")) + return sizeof(u32); + if (str_has_prefix(type, "__rel_loc ")) + return sizeof(u32); + + /* Uknown basic type, error */ + return -EINVAL; +} + +static void user_event_destroy_validators(struct user_event *user) +{ + struct user_event_validator *validator, *next; + struct list_head *head = &user->validators; + + list_for_each_entry_safe(validator, next, head, link) { + list_del(&validator->link); + kfree(validator); + } +} + +static void user_event_destroy_fields(struct user_event *user) +{ + struct ftrace_event_field *field, *next; + struct list_head *head = &user->fields; + + list_for_each_entry_safe(field, next, head, link) { + list_del(&field->link); + kfree(field); + } +} + +static int user_event_add_field(struct user_event *user, const char *type, + const char *name, int offset, int size, + int is_signed, int filter_type) +{ + struct user_event_validator *validator; + struct ftrace_event_field *field; + int validator_flags = 0; + + field = kmalloc(sizeof(*field), GFP_KERNEL); + + if (!field) + return -ENOMEM; + + if (str_has_prefix(type, "__data_loc ")) + goto add_validator; + + if (str_has_prefix(type, "__rel_loc ")) { + validator_flags |= VALIDATOR_REL; + goto add_validator; + } + + goto add_field; + +add_validator: + if (strstr(type, "char") != 0) + validator_flags |= VALIDATOR_ENSURE_NULL; + + validator = kmalloc(sizeof(*validator), GFP_KERNEL); + + if (!validator) { + kfree(field); + return -ENOMEM; + } + + validator->flags = validator_flags; + validator->offset = offset; + + /* Want sequential access when validating */ + list_add_tail(&validator->link, &user->validators); + +add_field: + field->type = type; + field->name = name; + field->offset = offset; + field->size = size; + field->is_signed = is_signed; + field->filter_type = filter_type; + + list_add(&field->link, &user->fields); + + /* + * Min size from user writes that are required, this does not include + * the size of trace_entry (common fields). + */ + user->min_size = (offset + size) - sizeof(struct trace_entry); + + return 0; +} + +/* + * Parses the values of a field within the description + * Format: type name [size] + */ +static int user_event_parse_field(char *field, struct user_event *user, + u32 *offset) +{ + char *part, *type, *name; + u32 depth = 0, saved_offset = *offset; + int len, size = -EINVAL; + bool is_struct = false; + + field = skip_spaces(field); + + if (*field == '\0') + return 0; + + /* Handle types that have a space within */ + len = str_has_prefix(field, "unsigned "); + if (len) + goto skip_next; + + len = str_has_prefix(field, "struct "); + if (len) { + is_struct = true; + goto skip_next; + } + + len = str_has_prefix(field, "__data_loc unsigned "); + if (len) + goto skip_next; + + len = str_has_prefix(field, "__data_loc "); + if (len) + goto skip_next; + + len = str_has_prefix(field, "__rel_loc unsigned "); + if (len) + goto skip_next; + + len = str_has_prefix(field, "__rel_loc "); + if (len) + goto skip_next; + + goto parse; +skip_next: + type = field; + field = strpbrk(field + len, " "); + + if (field == NULL) + return -EINVAL; + + *field++ = '\0'; + depth++; +parse: + name = NULL; + + while ((part = strsep(&field, " ")) != NULL) { + switch (depth++) { + case FIELD_DEPTH_TYPE: + type = part; + break; + case FIELD_DEPTH_NAME: + name = part; + break; + case FIELD_DEPTH_SIZE: + if (!is_struct) + return -EINVAL; + + if (kstrtou32(part, 10, &size)) + return -EINVAL; + break; + default: + return -EINVAL; + } + } + + if (depth < FIELD_DEPTH_SIZE || !name) + return -EINVAL; + + if (depth == FIELD_DEPTH_SIZE) + size = user_field_size(type); + + if (size == 0) + return -EINVAL; + + if (size < 0) + return size; + + *offset = saved_offset + size; + + return user_event_add_field(user, type, name, saved_offset, size, + type[0] != 'u', FILTER_OTHER); +} + +static void user_event_parse_flags(struct user_event *user, char *flags) +{ + char *flag; + + if (flags == NULL) + return; + + while ((flag = strsep(&flags, ",")) != NULL) { + if (strcmp(flag, "BPF_ITER") == 0) + user->flags |= FLAG_BPF_ITER; + } +} + +static int user_event_parse_fields(struct user_event *user, char *args) +{ + char *field; + u32 offset = sizeof(struct trace_entry); + int ret = -EINVAL; + + if (args == NULL) + return 0; + + while ((field = strsep(&args, ";")) != NULL) { + ret = user_event_parse_field(field, user, &offset); + + if (ret) + break; + } + + return ret; +} + +static struct trace_event_fields user_event_fields_array[1]; + +static const char *user_field_format(const char *type) +{ + if (strcmp(type, "s64") == 0) + return "%lld"; + if (strcmp(type, "u64") == 0) + return "%llu"; + if (strcmp(type, "s32") == 0) + return "%d"; + if (strcmp(type, "u32") == 0) + return "%u"; + if (strcmp(type, "int") == 0) + return "%d"; + if (strcmp(type, "unsigned int") == 0) + return "%u"; + if (strcmp(type, "s16") == 0) + return "%d"; + if (strcmp(type, "u16") == 0) + return "%u"; + if (strcmp(type, "short") == 0) + return "%d"; + if (strcmp(type, "unsigned short") == 0) + return "%u"; + if (strcmp(type, "s8") == 0) + return "%d"; + if (strcmp(type, "u8") == 0) + return "%u"; + if (strcmp(type, "char") == 0) + return "%d"; + if (strcmp(type, "unsigned char") == 0) + return "%u"; + if (strstr(type, "char[") != 0) + return "%s"; + + /* Unknown, likely struct, allowed treat as 64-bit */ + return "%llu"; +} + +static bool user_field_is_dyn_string(const char *type, const char **str_func) +{ + if (str_has_prefix(type, "__data_loc ")) { + *str_func = "__get_str"; + goto check; + } + + if (str_has_prefix(type, "__rel_loc ")) { + *str_func = "__get_rel_str"; + goto check; + } + + return false; +check: + return strstr(type, "char") != 0; +} + +#define LEN_OR_ZERO (len ? len - pos : 0) +static int user_event_set_print_fmt(struct user_event *user, char *buf, int len) +{ + struct ftrace_event_field *field, *next; + struct list_head *head = &user->fields; + int pos = 0, depth = 0; + const char *str_func; + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); + + list_for_each_entry_safe_reverse(field, next, head, link) { + if (depth != 0) + pos += snprintf(buf + pos, LEN_OR_ZERO, " "); + + pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s", + field->name, user_field_format(field->type)); + + depth++; + } + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); + + list_for_each_entry_safe_reverse(field, next, head, link) { + if (user_field_is_dyn_string(field->type, &str_func)) + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", %s(%s)", str_func, field->name); + else + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", REC->%s", field->name); + } + + return pos + 1; +} +#undef LEN_OR_ZERO + +static int user_event_create_print_fmt(struct user_event *user) +{ + char *print_fmt; + int len; + + len = user_event_set_print_fmt(user, NULL, 0); + + print_fmt = kmalloc(len, GFP_KERNEL); + + if (!print_fmt) + return -ENOMEM; + + user_event_set_print_fmt(user, print_fmt, len); + + user->call.print_fmt = print_fmt; + + return 0; +} + +static enum print_line_t user_event_print_trace(struct trace_iterator *iter, + int flags, + struct trace_event *event) +{ + /* Unsafe to try to decode user provided print_fmt, use hex */ + trace_print_hex_dump_seq(&iter->seq, "", DUMP_PREFIX_OFFSET, 16, + 1, iter->ent, iter->ent_size, true); + + return trace_handle_return(&iter->seq); +} + +static struct trace_event_functions user_event_funcs = { + .trace = user_event_print_trace, +}; + +static int user_event_set_call_visible(struct user_event *user, bool visible) +{ + int ret; + const struct cred *old_cred; + struct cred *cred; + + cred = prepare_creds(); + + if (!cred) + return -ENOMEM; + + /* + * While by default tracefs is locked down, systems can be configured + * to allow user_event files to be less locked down. The extreme case + * being "other" has read/write access to user_events_data/status. + * + * When not locked down, processes may not have have permissions to + * add/remove calls themselves to tracefs. We need to temporarily + * switch to root file permission to allow for this scenario. + */ + cred->fsuid = GLOBAL_ROOT_UID; + + old_cred = override_creds(cred); + + if (visible) + ret = trace_add_event_call(&user->call); + else + ret = trace_remove_event_call(&user->call); + + revert_creds(old_cred); + put_cred(cred); + + return ret; +} + +static int destroy_user_event(struct user_event *user) +{ + int ret = 0; + + /* Must destroy fields before call removal */ + user_event_destroy_fields(user); + + ret = user_event_set_call_visible(user, false); + + if (ret) + return ret; + + dyn_event_remove(&user->devent); + + register_page_data[user->index] = 0; + clear_bit(user->index, page_bitmap); + hash_del(&user->node); + + user_event_destroy_validators(user); + kfree(user->call.print_fmt); + kfree(EVENT_NAME(user)); + kfree(user); + + return ret; +} + +static struct user_event *find_user_event(char *name, u32 *outkey) +{ + struct user_event *user; + u32 key = user_event_key(name); + + *outkey = key; + + hash_for_each_possible(register_table, user, node, key) + if (!strcmp(EVENT_NAME(user), name)) { + atomic_inc(&user->refcnt); + return user; + } + + return NULL; +} + +static int user_event_validate(struct user_event *user, void *data, int len) +{ + struct list_head *head = &user->validators; + struct user_event_validator *validator; + void *pos, *end = data + len; + u32 loc, offset, size; + + list_for_each_entry(validator, head, link) { + pos = data + validator->offset; + + /* Already done min_size check, no bounds check here */ + loc = *(u32 *)pos; + offset = loc & 0xffff; + size = loc >> 16; + + if (likely(validator->flags & VALIDATOR_REL)) + pos += offset + sizeof(loc); + else + pos = data + offset; + + pos += size; + + if (unlikely(pos > end)) + return -EFAULT; + + if (likely(validator->flags & VALIDATOR_ENSURE_NULL)) + if (unlikely(*(char *)(pos - 1) != '\0')) + return -EFAULT; + } + + return 0; +} + +/* + * Writes the user supplied payload out to a trace file. + */ +static void user_event_ftrace(struct user_event *user, struct iov_iter *i, + void *tpdata, bool *faulted) +{ + struct trace_event_file *file; + struct trace_entry *entry; + struct trace_event_buffer event_buffer; + size_t size = sizeof(*entry) + i->count; + + file = (struct trace_event_file *)tpdata; + + if (!file || + !(file->flags & EVENT_FILE_FL_ENABLED) || + trace_trigger_soft_disabled(file)) + return; + + /* Allocates and fills trace_entry, + 1 of this is data payload */ + entry = trace_event_buffer_reserve(&event_buffer, file, size); + + if (unlikely(!entry)) + return; + + if (unlikely(!copy_nofault(entry + 1, i->count, i))) + goto discard; + + if (!list_empty(&user->validators) && + unlikely(user_event_validate(user, entry, size))) + goto discard; + + trace_event_buffer_commit(&event_buffer); + + return; +discard: + *faulted = true; + __trace_event_discard_commit(event_buffer.buffer, + event_buffer.event); +} + +#ifdef CONFIG_PERF_EVENTS +static void user_event_bpf(struct user_event *user, struct iov_iter *i) +{ + struct user_bpf_context context; + struct user_bpf_iter bpf_i; + char fast_data[MAX_STACK_BPF_DATA]; + void *temp = NULL; + + if ((user->flags & FLAG_BPF_ITER) && iter_is_iovec(i)) { + /* Raw iterator */ + context.data_type = USER_BPF_DATA_ITER; + context.data_len = i->count; + context.iter = &bpf_i; + + bpf_i.iov_offset = i->iov_offset; + bpf_i.iov = i->iov; + bpf_i.nr_segs = i->nr_segs; + } else if (i->nr_segs == 1 && iter_is_iovec(i)) { + /* Single buffer from user */ + context.data_type = USER_BPF_DATA_USER; + context.data_len = i->count; + context.udata = i->iov->iov_base + i->iov_offset; + } else { + /* Multi buffer from user */ + struct iov_iter copy = *i; + size_t copy_size = min_t(size_t, i->count, MAX_BPF_COPY_SIZE); + + context.data_type = USER_BPF_DATA_KERNEL; + context.kdata = fast_data; + + if (unlikely(copy_size > sizeof(fast_data))) { + temp = kmalloc(copy_size, GFP_NOWAIT); + + if (temp) + context.kdata = temp; + else + copy_size = sizeof(fast_data); + } + + context.data_len = copy_nofault(context.kdata, + copy_size, ©); + } + + trace_call_bpf(&user->call, &context); + + kfree(temp); +} + +/* + * Writes the user supplied payload out to perf ring buffer or eBPF program. + */ +static void user_event_perf(struct user_event *user, struct iov_iter *i, + void *tpdata, bool *faulted) +{ + struct hlist_head *perf_head; + + if (bpf_prog_array_valid(&user->call)) + user_event_bpf(user, i); + + perf_head = this_cpu_ptr(user->call.perf_events); + + if (perf_head && !hlist_empty(perf_head)) { + struct trace_entry *perf_entry; + struct pt_regs *regs; + size_t size = sizeof(*perf_entry) + i->count; + int context; + + perf_entry = perf_trace_buf_alloc(ALIGN(size, 8), + ®s, &context); + + if (unlikely(!perf_entry)) + return; + + perf_fetch_caller_regs(regs); + + if (unlikely(!copy_nofault(perf_entry + 1, i->count, i))) + goto discard; + + if (!list_empty(&user->validators) && + unlikely(user_event_validate(user, perf_entry, size))) + goto discard; + + perf_trace_buf_submit(perf_entry, size, context, + user->call.event.type, 1, regs, + perf_head, NULL); + + return; +discard: + *faulted = true; + perf_swevent_put_recursion_context(context); + } +} +#endif + +/* + * Update the register page that is shared between user processes. + */ +static void update_reg_page_for(struct user_event *user) +{ + struct tracepoint *tp = &user->tracepoint; + char status = 0; + + if (atomic_read(&tp->key.enabled) > 0) { + struct tracepoint_func *probe_func_ptr; + user_event_func_t probe_func; + + rcu_read_lock_sched(); + + probe_func_ptr = rcu_dereference_sched(tp->funcs); + + if (probe_func_ptr) { + do { + probe_func = probe_func_ptr->func; + + if (probe_func == user_event_ftrace) + status |= EVENT_STATUS_FTRACE; +#ifdef CONFIG_PERF_EVENTS + else if (probe_func == user_event_perf) + status |= EVENT_STATUS_PERF; +#endif + else + status |= EVENT_STATUS_OTHER; + } while ((++probe_func_ptr)->func); + } + + rcu_read_unlock_sched(); + } + + register_page_data[user->index] = status; +} + +/* + * Register callback for our events from tracing sub-systems. + */ +static int user_event_reg(struct trace_event_call *call, + enum trace_reg type, + void *data) +{ + struct user_event *user = (struct user_event *)call->data; + int ret = 0; + + if (!user) + return -ENOENT; + + switch (type) { + case TRACE_REG_REGISTER: + ret = tracepoint_probe_register(call->tp, + call->class->probe, + data); + if (!ret) + goto inc; + break; + + case TRACE_REG_UNREGISTER: + tracepoint_probe_unregister(call->tp, + call->class->probe, + data); + goto dec; + +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + ret = tracepoint_probe_register(call->tp, + call->class->perf_probe, + data); + if (!ret) + goto inc; + break; + + case TRACE_REG_PERF_UNREGISTER: + tracepoint_probe_unregister(call->tp, + call->class->perf_probe, + data); + goto dec; + + case TRACE_REG_PERF_OPEN: + case TRACE_REG_PERF_CLOSE: + case TRACE_REG_PERF_ADD: + case TRACE_REG_PERF_DEL: + break; +#endif + } + + return ret; +inc: + atomic_inc(&user->refcnt); + update_reg_page_for(user); + return 0; +dec: + update_reg_page_for(user); + atomic_dec(&user->refcnt); + return 0; +} + +static int user_event_create(const char *raw_command) +{ + struct user_event *user; + char *name; + int ret; + + if (!str_has_prefix(raw_command, USER_EVENTS_PREFIX)) + return -ECANCELED; + + raw_command += USER_EVENTS_PREFIX_LEN; + raw_command = skip_spaces(raw_command); + + name = kstrdup(raw_command, GFP_KERNEL); + + if (!name) + return -ENOMEM; + + mutex_lock(®_mutex); + + ret = user_event_parse_cmd(name, &user); + + if (!ret) + atomic_dec(&user->refcnt); + + mutex_unlock(®_mutex); + + if (ret) + kfree(name); + + return ret; +} + +static int user_event_show(struct seq_file *m, struct dyn_event *ev) +{ + struct user_event *user = container_of(ev, struct user_event, devent); + struct ftrace_event_field *field, *next; + struct list_head *head; + int depth = 0; + + seq_printf(m, "%s%s", USER_EVENTS_PREFIX, EVENT_NAME(user)); + + head = trace_get_fields(&user->call); + + list_for_each_entry_safe_reverse(field, next, head, link) { + if (depth == 0) + seq_puts(m, " "); + else + seq_puts(m, "; "); + + seq_printf(m, "%s %s", field->type, field->name); + + if (str_has_prefix(field->type, "struct ")) + seq_printf(m, " %d", field->size); + + depth++; + } + + seq_puts(m, "\n"); + + return 0; +} + +static bool user_event_is_busy(struct dyn_event *ev) +{ + struct user_event *user = container_of(ev, struct user_event, devent); + + return atomic_read(&user->refcnt) != 0; +} + +static int user_event_free(struct dyn_event *ev) +{ + struct user_event *user = container_of(ev, struct user_event, devent); + + if (atomic_read(&user->refcnt) != 0) + return -EBUSY; + + return destroy_user_event(user); +} + +static bool user_field_match(struct ftrace_event_field *field, int argc, + const char **argv, int *iout) +{ + char *field_name, *arg_name; + int len, pos, i = *iout; + bool colon = false, match = false; + + if (i >= argc) + return false; + + len = MAX_FIELD_ARG_NAME; + field_name = kmalloc(len, GFP_KERNEL); + arg_name = kmalloc(len, GFP_KERNEL); + + if (!arg_name || !field_name) + goto out; + + pos = 0; + + for (; i < argc; ++i) { + if (i != *iout) + pos += snprintf(arg_name + pos, len - pos, " "); + + pos += snprintf(arg_name + pos, len - pos, argv[i]); + + if (strchr(argv[i], ';')) { + ++i; + colon = true; + break; + } + } + + pos = 0; + + pos += snprintf(field_name + pos, len - pos, field->type); + pos += snprintf(field_name + pos, len - pos, " "); + pos += snprintf(field_name + pos, len - pos, field->name); + + if (colon) + pos += snprintf(field_name + pos, len - pos, ";"); + + *iout = i; + + match = strcmp(arg_name, field_name) == 0; +out: + kfree(arg_name); + kfree(field_name); + + return match; +} + +static bool user_fields_match(struct user_event *user, int argc, + const char **argv) +{ + struct ftrace_event_field *field, *next; + struct list_head *head = &user->fields; + int i = 0; + + list_for_each_entry_safe_reverse(field, next, head, link) + if (!user_field_match(field, argc, argv, &i)) + return false; + + if (i != argc) + return false; + + return true; +} + +static bool user_event_match(const char *system, const char *event, + int argc, const char **argv, struct dyn_event *ev) +{ + struct user_event *user = container_of(ev, struct user_event, devent); + bool match; + + match = strcmp(EVENT_NAME(user), event) == 0 && + (!system || strcmp(system, USER_EVENTS_SYSTEM) == 0); + + if (match && argc > 0) + match = user_fields_match(user, argc, argv); + + return match; +} + +static struct dyn_event_operations user_event_dops = { + .create = user_event_create, + .show = user_event_show, + .is_busy = user_event_is_busy, + .free = user_event_free, + .match = user_event_match, +}; + +static int user_event_trace_register(struct user_event *user) +{ + int ret; + + ret = register_trace_event(&user->call.event); + + if (!ret) + return -ENODEV; + + ret = user_event_set_call_visible(user, true); + + if (ret) + unregister_trace_event(&user->call.event); + + return ret; +} + +/* + * Parses the event name, arguments and flags then registers if successful. + * The name buffer lifetime is owned by this method for success cases only. + * Upon success the returned user_event has its ref count increased by 1. + */ +static int user_event_parse(char *name, char *args, char *flags, + struct user_event **newuser) +{ + int ret; + int index; + u32 key; + struct user_event *user; + + /* Prevent dyn_event from racing */ + mutex_lock(&event_mutex); + user = find_user_event(name, &key); + mutex_unlock(&event_mutex); + + if (user) { + *newuser = user; + /* + * Name is allocated by caller, free it since it already exists. + * Caller only worries about failure cases for freeing. + */ + kfree(name); + return 0; + } + + index = find_first_zero_bit(page_bitmap, MAX_EVENTS); + + if (index == MAX_EVENTS) + return -EMFILE; + + user = kzalloc(sizeof(*user), GFP_KERNEL); + + if (!user) + return -ENOMEM; + + INIT_LIST_HEAD(&user->class.fields); + INIT_LIST_HEAD(&user->fields); + INIT_LIST_HEAD(&user->validators); + + user->tracepoint.name = name; + + user_event_parse_flags(user, flags); + + ret = user_event_parse_fields(user, args); + + if (ret) + goto put_user; + + ret = user_event_create_print_fmt(user); + + if (ret) + goto put_user; + + user->call.data = user; + user->call.class = &user->class; + user->call.name = name; + user->call.flags = TRACE_EVENT_FL_TRACEPOINT; + user->call.tp = &user->tracepoint; + user->call.event.funcs = &user_event_funcs; + + user->class.system = USER_EVENTS_SYSTEM; + user->class.fields_array = user_event_fields_array; + user->class.get_fields = user_event_get_fields; + user->class.reg = user_event_reg; + user->class.probe = user_event_ftrace; +#ifdef CONFIG_PERF_EVENTS + user->class.perf_probe = user_event_perf; +#endif + + mutex_lock(&event_mutex); + ret = user_event_trace_register(user); + mutex_unlock(&event_mutex); + + if (ret) + goto put_user; + + user->index = index; + + /* Ensure we track ref */ + atomic_inc(&user->refcnt); + + dyn_event_init(&user->devent, &user_event_dops); + dyn_event_add(&user->devent, &user->call); + set_bit(user->index, page_bitmap); + hash_add(register_table, &user->node, key); + + *newuser = user; + return 0; +put_user: + user_event_destroy_fields(user); + user_event_destroy_validators(user); + kfree(user); + return ret; +} + +/* + * Deletes a previously created event if it is no longer being used. + */ +static int delete_user_event(char *name) +{ + u32 key; + int ret; + struct user_event *user = find_user_event(name, &key); + + if (!user) + return -ENOENT; + + /* Ensure we are the last ref */ + if (atomic_read(&user->refcnt) != 1) { + ret = -EBUSY; + goto put_ref; + } + + ret = destroy_user_event(user); + + if (ret) + goto put_ref; + + return ret; +put_ref: + /* No longer have this ref */ + atomic_dec(&user->refcnt); + + return ret; +} + +/* + * Validates the user payload and writes via iterator. + */ +static ssize_t user_events_write_core(struct file *file, struct iov_iter *i) +{ + struct user_event_refs *refs; + struct user_event *user = NULL; + struct tracepoint *tp; + ssize_t ret = i->count; + int idx; + + if (unlikely(copy_from_iter(&idx, sizeof(idx), i) != sizeof(idx))) + return -EFAULT; + + rcu_read_lock_sched(); + + refs = rcu_dereference_sched(file->private_data); + + /* + * The refs->events array is protected by RCU, and new items may be + * added. But the user retrieved from indexing into the events array + * shall be immutable while the file is opened. + */ + if (likely(refs && idx < refs->count)) + user = refs->events[idx]; + + rcu_read_unlock_sched(); + + if (unlikely(user == NULL)) + return -ENOENT; + + if (unlikely(i->count < user->min_size)) + return -EINVAL; + + tp = &user->tracepoint; + + /* + * It's possible key.enabled disables after this check, however + * we don't mind if a few events are included in this condition. + */ + if (likely(atomic_read(&tp->key.enabled) > 0)) { + struct tracepoint_func *probe_func_ptr; + user_event_func_t probe_func; + struct iov_iter copy; + void *tpdata; + bool faulted; + + if (unlikely(fault_in_iov_iter_readable(i, i->count))) + return -EFAULT; + + faulted = false; + + rcu_read_lock_sched(); + + probe_func_ptr = rcu_dereference_sched(tp->funcs); + + if (probe_func_ptr) { + do { + copy = *i; + probe_func = probe_func_ptr->func; + tpdata = probe_func_ptr->data; + probe_func(user, ©, tpdata, &faulted); + } while ((++probe_func_ptr)->func); + } + + rcu_read_unlock_sched(); + + if (unlikely(faulted)) + return -EFAULT; + } + + return ret; +} + +static ssize_t user_events_write(struct file *file, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct iovec iov; + struct iov_iter i; + + if (unlikely(*ppos != 0)) + return -EFAULT; + + if (unlikely(import_single_range(READ, (char *)ubuf, count, &iov, &i))) + return -EFAULT; + + return user_events_write_core(file, &i); +} + +static ssize_t user_events_write_iter(struct kiocb *kp, struct iov_iter *i) +{ + return user_events_write_core(kp->ki_filp, i); +} + +static int user_events_ref_add(struct file *file, struct user_event *user) +{ + struct user_event_refs *refs, *new_refs; + int i, size, count = 0; + + refs = rcu_dereference_protected(file->private_data, + lockdep_is_held(®_mutex)); + + if (refs) { + count = refs->count; + + for (i = 0; i < count; ++i) + if (refs->events[i] == user) + return i; + } + + size = struct_size(refs, events, count + 1); + + new_refs = kzalloc(size, GFP_KERNEL); + + if (!new_refs) + return -ENOMEM; + + new_refs->count = count + 1; + + for (i = 0; i < count; ++i) + new_refs->events[i] = refs->events[i]; + + new_refs->events[i] = user; + + atomic_inc(&user->refcnt); + + rcu_assign_pointer(file->private_data, new_refs); + + if (refs) + kfree_rcu(refs, rcu); + + return i; +} + +static long user_reg_get(struct user_reg __user *ureg, struct user_reg *kreg) +{ + u32 size; + long ret; + + ret = get_user(size, &ureg->size); + + if (ret) + return ret; + + if (size > PAGE_SIZE) + return -E2BIG; + + return copy_struct_from_user(kreg, sizeof(*kreg), ureg, size); +} + +/* + * Registers a user_event on behalf of a user process. + */ +static long user_events_ioctl_reg(struct file *file, unsigned long uarg) +{ + struct user_reg __user *ureg = (struct user_reg __user *)uarg; + struct user_reg reg; + struct user_event *user; + char *name; + long ret; + + ret = user_reg_get(ureg, ®); + + if (ret) + return ret; + + name = strndup_user((const char __user *)(uintptr_t)reg.name_args, + MAX_EVENT_DESC); + + if (IS_ERR(name)) { + ret = PTR_ERR(name); + return ret; + } + + ret = user_event_parse_cmd(name, &user); + + if (ret) { + kfree(name); + return ret; + } + + ret = user_events_ref_add(file, user); + + /* No longer need parse ref, ref_add either worked or not */ + atomic_dec(&user->refcnt); + + /* Positive number is index and valid */ + if (ret < 0) + return ret; + + put_user((u32)ret, &ureg->write_index); + put_user(user->index, &ureg->status_index); + + return 0; +} + +/* + * Deletes a user_event on behalf of a user process. + */ +static long user_events_ioctl_del(struct file *file, unsigned long uarg) +{ + void __user *ubuf = (void __user *)uarg; + char *name; + long ret; + + name = strndup_user(ubuf, MAX_EVENT_DESC); + + if (IS_ERR(name)) + return PTR_ERR(name); + + /* event_mutex prevents dyn_event from racing */ + mutex_lock(&event_mutex); + ret = delete_user_event(name); + mutex_unlock(&event_mutex); + + kfree(name); + + return ret; +} + +/* + * Handles the ioctl from user mode to register or alter operations. + */ +static long user_events_ioctl(struct file *file, unsigned int cmd, + unsigned long uarg) +{ + long ret = -ENOTTY; + + switch (cmd) { + case DIAG_IOCSREG: + mutex_lock(®_mutex); + ret = user_events_ioctl_reg(file, uarg); + mutex_unlock(®_mutex); + break; + + case DIAG_IOCSDEL: + mutex_lock(®_mutex); + ret = user_events_ioctl_del(file, uarg); + mutex_unlock(®_mutex); + break; + } + + return ret; +} + +/* + * Handles the final close of the file from user mode. + */ +static int user_events_release(struct inode *node, struct file *file) +{ + struct user_event_refs *refs; + struct user_event *user; + int i; + + /* + * Ensure refs cannot change under any situation by taking the + * register mutex during the final freeing of the references. + */ + mutex_lock(®_mutex); + + refs = file->private_data; + + if (!refs) + goto out; + + /* + * The lifetime of refs has reached an end, it's tied to this file. + * The underlying user_events are ref counted, and cannot be freed. + * After this decrement, the user_events may be freed elsewhere. + */ + for (i = 0; i < refs->count; ++i) { + user = refs->events[i]; + + if (user) + atomic_dec(&user->refcnt); + } +out: + file->private_data = NULL; + + mutex_unlock(®_mutex); + + kfree(refs); + + return 0; +} + +static const struct file_operations user_data_fops = { + .write = user_events_write, + .write_iter = user_events_write_iter, + .unlocked_ioctl = user_events_ioctl, + .release = user_events_release, +}; + +/* + * Maps the shared page into the user process for checking if event is enabled. + */ +static int user_status_mmap(struct file *file, struct vm_area_struct *vma) +{ + unsigned long size = vma->vm_end - vma->vm_start; + + if (size != MAX_EVENTS) + return -EINVAL; + + return remap_pfn_range(vma, vma->vm_start, + virt_to_phys(register_page_data) >> PAGE_SHIFT, + size, vm_get_page_prot(VM_READ)); +} + +static void *user_seq_start(struct seq_file *m, loff_t *pos) +{ + if (*pos) + return NULL; + + return (void *)1; +} + +static void *user_seq_next(struct seq_file *m, void *p, loff_t *pos) +{ + ++*pos; + return NULL; +} + +static void user_seq_stop(struct seq_file *m, void *p) +{ +} + +static int user_seq_show(struct seq_file *m, void *p) +{ + struct user_event *user; + char status; + int i, active = 0, busy = 0, flags; + + mutex_lock(®_mutex); + + hash_for_each(register_table, i, user, node) { + status = register_page_data[user->index]; + flags = user->flags; + + seq_printf(m, "%d:%s", user->index, EVENT_NAME(user)); + + if (flags != 0 || status != 0) + seq_puts(m, " #"); + + if (status != 0) { + seq_puts(m, " Used by"); + if (status & EVENT_STATUS_FTRACE) + seq_puts(m, " ftrace"); + if (status & EVENT_STATUS_PERF) + seq_puts(m, " perf"); + if (status & EVENT_STATUS_OTHER) + seq_puts(m, " other"); + busy++; + } + + if (flags & FLAG_BPF_ITER) + seq_puts(m, " FLAG:BPF_ITER"); + + seq_puts(m, "\n"); + active++; + } + + mutex_unlock(®_mutex); + + seq_puts(m, "\n"); + seq_printf(m, "Active: %d\n", active); + seq_printf(m, "Busy: %d\n", busy); + seq_printf(m, "Max: %ld\n", MAX_EVENTS); + + return 0; +} + +static const struct seq_operations user_seq_ops = { + .start = user_seq_start, + .next = user_seq_next, + .stop = user_seq_stop, + .show = user_seq_show, +}; + +static int user_status_open(struct inode *node, struct file *file) +{ + return seq_open(file, &user_seq_ops); +} + +static const struct file_operations user_status_fops = { + .open = user_status_open, + .mmap = user_status_mmap, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +/* + * Creates a set of tracefs files to allow user mode interactions. + */ +static int create_user_tracefs(void) +{ + struct dentry *edata, *emmap; + + edata = tracefs_create_file("user_events_data", TRACE_MODE_WRITE, + NULL, NULL, &user_data_fops); + + if (!edata) { + pr_warn("Could not create tracefs 'user_events_data' entry\n"); + goto err; + } + + /* mmap with MAP_SHARED requires writable fd */ + emmap = tracefs_create_file("user_events_status", TRACE_MODE_WRITE, + NULL, NULL, &user_status_fops); + + if (!emmap) { + tracefs_remove(edata); + pr_warn("Could not create tracefs 'user_events_mmap' entry\n"); + goto err; + } + + return 0; +err: + return -ENODEV; +} + +static void set_page_reservations(bool set) +{ + int page; + + for (page = 0; page < MAX_PAGES; ++page) { + void *addr = register_page_data + (PAGE_SIZE * page); + + if (set) + SetPageReserved(virt_to_page(addr)); + else + ClearPageReserved(virt_to_page(addr)); + } +} + +static int __init trace_events_user_init(void) +{ + struct page *pages; + int ret; + + /* Zero all bits beside 0 (which is reserved for failures) */ + bitmap_zero(page_bitmap, MAX_EVENTS); + set_bit(0, page_bitmap); + + pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, MAX_PAGE_ORDER); + if (!pages) + return -ENOMEM; + register_page_data = page_address(pages); + + set_page_reservations(true); + + ret = create_user_tracefs(); + + if (ret) { + pr_warn("user_events could not register with tracefs\n"); + set_page_reservations(false); + __free_pages(pages, MAX_PAGE_ORDER); + return ret; + } + + if (dyn_event_register(&user_event_dops)) + pr_warn("user_events could not register with dyn_events\n"); + + return 0; +} + +fs_initcall(trace_events_user_init); diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index 993b0ed..45796d8 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -45,7 +45,7 @@ probe_sched_wakeup(void *ignore, struct task_struct *wakee) if (!flags) return; - tracing_record_taskinfo(current, flags); + tracing_record_taskinfo_sched_switch(current, wakee, flags); } static int tracing_sched_register(void) diff --git a/samples/Kconfig b/samples/Kconfig index 22cc921..10e021c 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -14,7 +14,13 @@ config SAMPLE_TRACE_EVENTS tristate "Build trace_events examples -- loadable modules only" depends on EVENT_TRACING && m help - This build trace event example modules. + This builds the trace event example module. + +config SAMPLE_TRACE_CUSTOM_EVENTS + tristate "Build custom trace event example -- loadable modules only" + depends on EVENT_TRACING && m + help + This builds the custom trace event example module. config SAMPLE_TRACE_PRINTK tristate "Build trace_printk module - tests various trace_printk formats" diff --git a/samples/Makefile b/samples/Makefile index 1ae4de9..448343e 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_SAMPLE_RPMSG_CLIENT) += rpmsg/ subdir-$(CONFIG_SAMPLE_SECCOMP) += seccomp subdir-$(CONFIG_SAMPLE_TIMER) += timers obj-$(CONFIG_SAMPLE_TRACE_EVENTS) += trace_events/ +obj-$(CONFIG_SAMPLE_TRACE_CUSTOM_EVENTS) += trace_events/ obj-$(CONFIG_SAMPLE_TRACE_PRINTK) += trace_printk/ obj-$(CONFIG_SAMPLE_FTRACE_DIRECT) += ftrace/ obj-$(CONFIG_SAMPLE_FTRACE_DIRECT_MULTI) += ftrace/ diff --git a/samples/trace_events/Makefile b/samples/trace_events/Makefile index b78344e..b3808bb 100644 --- a/samples/trace_events/Makefile +++ b/samples/trace_events/Makefile @@ -11,5 +11,7 @@ # Here trace-events-sample.c does the CREATE_TRACE_POINTS. # CFLAGS_trace-events-sample.o := -I$(src) +CFLAGS_trace_custom_sched.o := -I$(src) obj-$(CONFIG_SAMPLE_TRACE_EVENTS) += trace-events-sample.o +obj-$(CONFIG_SAMPLE_TRACE_CUSTOM_EVENTS) += trace_custom_sched.o diff --git a/samples/trace_events/trace_custom_sched.c b/samples/trace_events/trace_custom_sched.c new file mode 100644 index 0000000..b99d9ab --- /dev/null +++ b/samples/trace_events/trace_custom_sched.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * event tracer + * + * Copyright (C) 2022 Google Inc, Steven Rostedt + */ + +#define pr_fmt(fmt) fmt + +#include +#include +#include +#include + +/* + * Must include the event header that the custom event will attach to, + * from the C file, and not in the custom header file. + */ +#include + +/* Declare CREATE_CUSTOM_TRACE_EVENTS before including custom header */ +#define CREATE_CUSTOM_TRACE_EVENTS + +#include "trace_custom_sched.h" + +/* + * As the trace events are not exported to modules, the use of + * for_each_kernel_tracepoint() is needed to find the trace event + * to attach to. The fct() function below, is a callback that + * will be called for every event. + * + * Helper functions are created by the TRACE_CUSTOM_EVENT() macro + * update the event. Those are of the form: + * + * trace_custom_event__update() + * + * Where is the event to attach. + */ +static void fct(struct tracepoint *tp, void *priv) +{ + trace_custom_event_sched_switch_update(tp); + trace_custom_event_sched_waking_update(tp); +} + +static int __init trace_sched_init(void) +{ + for_each_kernel_tracepoint(fct, NULL); + return 0; +} + +static void __exit trace_sched_exit(void) +{ +} + +module_init(trace_sched_init); +module_exit(trace_sched_exit); + +MODULE_AUTHOR("Steven Rostedt"); +MODULE_DESCRIPTION("Custom scheduling events"); +MODULE_LICENSE("GPL"); diff --git a/samples/trace_events/trace_custom_sched.h b/samples/trace_events/trace_custom_sched.h new file mode 100644 index 0000000..9fdd8e7 --- /dev/null +++ b/samples/trace_events/trace_custom_sched.h @@ -0,0 +1,96 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Like the headers that use TRACE_EVENT(), the TRACE_CUSTOM_EVENT() + * needs a header that allows for multiple inclusions. + * + * Test for a unique name (here we have _TRACE_CUSTOM_SCHED_H), + * also allowing to continue if TRACE_CUSTOM_MULTI_READ is defined. + */ +#if !defined(_TRACE_CUSTOM_SCHED_H) || defined(TRACE_CUSTOM_MULTI_READ) +#define _TRACE_CUSTOM_SCHED_H + +/* Include linux/trace_events.h for initial defines of TRACE_CUSTOM_EVENT() */ +#include + +/* + * TRACE_CUSTOM_EVENT() is just like TRACE_EVENT(). The first parameter + * is the event name of an existing event where the TRACE_EVENT has been included + * in the C file before including this file. + */ +TRACE_CUSTOM_EVENT(sched_switch, + + /* + * The TP_PROTO() and TP_ARGS must match the trace event + * that the custom event is using. + */ + TP_PROTO(bool preempt, + unsigned int prev_state, + struct task_struct *prev, + struct task_struct *next), + + TP_ARGS(preempt, prev_state, prev, next), + + /* + * The next fields are where the customization happens. + * The TP_STRUCT__entry() defines what will be recorded + * in the ring buffer when the custom event triggers. + * + * The rest is just like the TRACE_EVENT() macro except that + * it uses the custom entry. + */ + TP_STRUCT__entry( + __field( unsigned short, prev_prio ) + __field( unsigned short, next_prio ) + __field( pid_t, next_pid ) + ), + + TP_fast_assign( + __entry->prev_prio = prev->prio; + __entry->next_pid = next->pid; + __entry->next_prio = next->prio; + ), + + TP_printk("prev_prio=%d next_pid=%d next_prio=%d", + __entry->prev_prio, __entry->next_pid, __entry->next_prio) +) + + +TRACE_CUSTOM_EVENT(sched_waking, + + TP_PROTO(struct task_struct *p), + + TP_ARGS(p), + + TP_STRUCT__entry( + __field( pid_t, pid ) + __field( unsigned short, prio ) + ), + + TP_fast_assign( + __entry->pid = p->pid; + __entry->prio = p->prio; + ), + + TP_printk("pid=%d prio=%d", __entry->pid, __entry->prio) +) +#endif +/* + * Just like the headers that create TRACE_EVENTs, the below must + * be outside the protection of the above #if block. + */ + +/* + * It is required that the Makefile includes: + * CFLAGS_.o := -I$(src) + */ +#undef TRACE_INCLUDE_PATH +#undef TRACE_INCLUDE_FILE +#define TRACE_INCLUDE_PATH . + +/* + * It is requred that the TRACE_INCLUDE_FILE be the same + * as this file without the ".h". + */ +#define TRACE_INCLUDE_FILE trace_custom_sched +#include diff --git a/samples/user_events/Makefile b/samples/user_events/Makefile new file mode 100644 index 0000000..7252b58 --- /dev/null +++ b/samples/user_events/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 +CFLAGS += -Wl,-no-as-needed -Wall -I../../usr/include + +example: example.o +example.o: example.c diff --git a/samples/user_events/example.c b/samples/user_events/example.c new file mode 100644 index 0000000..4f5778e --- /dev/null +++ b/samples/user_events/example.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2021, Microsoft Corporation. + * + * Authors: + * Beau Belgrave + */ + +#include +#include +#include +#include +#include +#include +#include + +/* Assumes debugfs is mounted */ +const char *data_file = "/sys/kernel/debug/tracing/user_events_data"; +const char *status_file = "/sys/kernel/debug/tracing/user_events_status"; + +static int event_status(char **status) +{ + int fd = open(status_file, O_RDONLY); + + *status = mmap(NULL, sysconf(_SC_PAGESIZE), PROT_READ, + MAP_SHARED, fd, 0); + + close(fd); + + if (*status == MAP_FAILED) + return -1; + + return 0; +} + +static int event_reg(int fd, const char *command, int *status, int *write) +{ + struct user_reg reg = {0}; + + reg.size = sizeof(reg); + reg.name_args = (__u64)command; + + if (ioctl(fd, DIAG_IOCSREG, ®) == -1) + return -1; + + *status = reg.status_index; + *write = reg.write_index; + + return 0; +} + +int main(int argc, char **argv) +{ + int data_fd, status, write; + char *status_page; + struct iovec io[2]; + __u32 count = 0; + + if (event_status(&status_page) == -1) + return errno; + + data_fd = open(data_file, O_RDWR); + + if (event_reg(data_fd, "test u32 count", &status, &write) == -1) + return errno; + + /* Setup iovec */ + io[0].iov_base = &write; + io[0].iov_len = sizeof(write); + io[1].iov_base = &count; + io[1].iov_len = sizeof(count); + +ask: + printf("Press enter to check status...\n"); + getchar(); + + /* Check if anyone is listening */ + if (status_page[status]) { + /* Yep, trace out our data */ + writev(data_fd, (const struct iovec *)io, 2); + + /* Increase the count */ + count++; + + printf("Something was attached, wrote data\n"); + } + + goto ask; + + return 0; +} diff --git a/tools/testing/selftests/user_events/Makefile b/tools/testing/selftests/user_events/Makefile new file mode 100644 index 0000000..c765d86 --- /dev/null +++ b/tools/testing/selftests/user_events/Makefile @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0 +CFLAGS += -Wl,-no-as-needed -Wall -I../../../../usr/include +LDLIBS += -lrt -lpthread -lm + +TEST_GEN_PROGS = ftrace_test dyn_test perf_test + +TEST_FILES := settings + +include ../lib.mk diff --git a/tools/testing/selftests/user_events/dyn_test.c b/tools/testing/selftests/user_events/dyn_test.c new file mode 100644 index 0000000..d6265d1 --- /dev/null +++ b/tools/testing/selftests/user_events/dyn_test.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * User Events Dyn Events Test Program + * + * Copyright (c) 2021 Beau Belgrave + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest_harness.h" + +const char *dyn_file = "/sys/kernel/debug/tracing/dynamic_events"; +const char *clear = "!u:__test_event"; + +static int Append(const char *value) +{ + int fd = open(dyn_file, O_RDWR | O_APPEND); + int ret = write(fd, value, strlen(value)); + + close(fd); + return ret; +} + +#define CLEAR() \ +do { \ + int ret = Append(clear); \ + if (ret == -1) \ + ASSERT_EQ(ENOENT, errno); \ +} while (0) + +#define TEST_PARSE(x) \ +do { \ + ASSERT_NE(-1, Append(x)); \ + CLEAR(); \ +} while (0) + +#define TEST_NPARSE(x) ASSERT_EQ(-1, Append(x)) + +FIXTURE(user) { +}; + +FIXTURE_SETUP(user) { + CLEAR(); +} + +FIXTURE_TEARDOWN(user) { + CLEAR(); +} + +TEST_F(user, basic_types) { + /* All should work */ + TEST_PARSE("u:__test_event u64 a"); + TEST_PARSE("u:__test_event u32 a"); + TEST_PARSE("u:__test_event u16 a"); + TEST_PARSE("u:__test_event u8 a"); + TEST_PARSE("u:__test_event char a"); + TEST_PARSE("u:__test_event unsigned char a"); + TEST_PARSE("u:__test_event int a"); + TEST_PARSE("u:__test_event unsigned int a"); + TEST_PARSE("u:__test_event short a"); + TEST_PARSE("u:__test_event unsigned short a"); + TEST_PARSE("u:__test_event char[20] a"); + TEST_PARSE("u:__test_event unsigned char[20] a"); + TEST_PARSE("u:__test_event char[0x14] a"); + TEST_PARSE("u:__test_event unsigned char[0x14] a"); + /* Bad size format should fail */ + TEST_NPARSE("u:__test_event char[aa] a"); + /* Large size should fail */ + TEST_NPARSE("u:__test_event char[9999] a"); + /* Long size string should fail */ + TEST_NPARSE("u:__test_event char[0x0000000000001] a"); +} + +TEST_F(user, loc_types) { + /* All should work */ + TEST_PARSE("u:__test_event __data_loc char[] a"); + TEST_PARSE("u:__test_event __data_loc unsigned char[] a"); + TEST_PARSE("u:__test_event __rel_loc char[] a"); + TEST_PARSE("u:__test_event __rel_loc unsigned char[] a"); +} + +TEST_F(user, size_types) { + /* Should work */ + TEST_PARSE("u:__test_event struct custom a 20"); + /* Size not specified on struct should fail */ + TEST_NPARSE("u:__test_event struct custom a"); + /* Size specified on non-struct should fail */ + TEST_NPARSE("u:__test_event char a 20"); +} + +TEST_F(user, flags) { + /* Should work */ + TEST_PARSE("u:__test_event:BPF_ITER u32 a"); + /* Forward compat */ + TEST_PARSE("u:__test_event:BPF_ITER,FLAG_FUTURE u32 a"); +} + +TEST_F(user, matching) { + /* Register */ + ASSERT_NE(-1, Append("u:__test_event struct custom a 20")); + /* Should not match */ + TEST_NPARSE("!u:__test_event struct custom b"); + /* Should match */ + TEST_PARSE("!u:__test_event struct custom a"); + /* Multi field reg */ + ASSERT_NE(-1, Append("u:__test_event u32 a; u32 b")); + /* Non matching cases */ + TEST_NPARSE("!u:__test_event u32 a"); + TEST_NPARSE("!u:__test_event u32 b"); + TEST_NPARSE("!u:__test_event u32 a; u32 "); + TEST_NPARSE("!u:__test_event u32 a; u32 a"); + /* Matching case */ + TEST_PARSE("!u:__test_event u32 a; u32 b"); + /* Register */ + ASSERT_NE(-1, Append("u:__test_event u32 a; u32 b")); + /* Ensure trailing semi-colon case */ + TEST_PARSE("!u:__test_event u32 a; u32 b;"); +} + +int main(int argc, char **argv) +{ + return test_harness_run(argc, argv); +} diff --git a/tools/testing/selftests/user_events/ftrace_test.c b/tools/testing/selftests/user_events/ftrace_test.c new file mode 100644 index 0000000..a80fb5e --- /dev/null +++ b/tools/testing/selftests/user_events/ftrace_test.c @@ -0,0 +1,452 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * User Events FTrace Test Program + * + * Copyright (c) 2021 Beau Belgrave + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest_harness.h" + +const char *data_file = "/sys/kernel/debug/tracing/user_events_data"; +const char *status_file = "/sys/kernel/debug/tracing/user_events_status"; +const char *enable_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/enable"; +const char *trace_file = "/sys/kernel/debug/tracing/trace"; +const char *fmt_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/format"; + +static int trace_bytes(void) +{ + int fd = open(trace_file, O_RDONLY); + char buf[256]; + int bytes = 0, got; + + if (fd == -1) + return -1; + + while (true) { + got = read(fd, buf, sizeof(buf)); + + if (got == -1) + return -1; + + if (got == 0) + break; + + bytes += got; + } + + close(fd); + + return bytes; +} + +static int skip_until_empty_line(FILE *fp) +{ + int c, last = 0; + + while (true) { + c = getc(fp); + + if (c == EOF) + break; + + if (last == '\n' && c == '\n') + return 0; + + last = c; + } + + return -1; +} + +static int get_print_fmt(char *buffer, int len) +{ + FILE *fp = fopen(fmt_file, "r"); + char *newline; + + if (!fp) + return -1; + + /* Read until empty line (Skip Common) */ + if (skip_until_empty_line(fp) < 0) + goto err; + + /* Read until empty line (Skip Properties) */ + if (skip_until_empty_line(fp) < 0) + goto err; + + /* Read in print_fmt: */ + if (fgets(buffer, len, fp) == NULL) + goto err; + + newline = strchr(buffer, '\n'); + + if (newline) + *newline = '\0'; + + fclose(fp); + + return 0; +err: + fclose(fp); + + return -1; +} + +static int clear(void) +{ + int fd = open(data_file, O_RDWR); + + if (fd == -1) + return -1; + + if (ioctl(fd, DIAG_IOCSDEL, "__test_event") == -1) + if (errno != ENOENT) + return -1; + + close(fd); + + return 0; +} + +static int check_print_fmt(const char *event, const char *expected) +{ + struct user_reg reg = {0}; + char print_fmt[256]; + int ret; + int fd; + + /* Ensure cleared */ + ret = clear(); + + if (ret != 0) + return ret; + + fd = open(data_file, O_RDWR); + + if (fd == -1) + return fd; + + reg.size = sizeof(reg); + reg.name_args = (__u64)event; + + /* Register should work */ + ret = ioctl(fd, DIAG_IOCSREG, ®); + + close(fd); + + if (ret != 0) + return ret; + + /* Ensure correct print_fmt */ + ret = get_print_fmt(print_fmt, sizeof(print_fmt)); + + if (ret != 0) + return ret; + + return strcmp(print_fmt, expected); +} + +FIXTURE(user) { + int status_fd; + int data_fd; + int enable_fd; +}; + +FIXTURE_SETUP(user) { + self->status_fd = open(status_file, O_RDONLY); + ASSERT_NE(-1, self->status_fd); + + self->data_fd = open(data_file, O_RDWR); + ASSERT_NE(-1, self->data_fd); + + self->enable_fd = -1; +} + +FIXTURE_TEARDOWN(user) { + close(self->status_fd); + close(self->data_fd); + + if (self->enable_fd != -1) { + write(self->enable_fd, "0", sizeof("0")); + close(self->enable_fd); + } + + ASSERT_EQ(0, clear()); +} + +TEST_F(user, register_events) { + struct user_reg reg = {0}; + int page_size = sysconf(_SC_PAGESIZE); + char *status_page; + + reg.size = sizeof(reg); + reg.name_args = (__u64)"__test_event u32 field1; u32 field2"; + + status_page = mmap(NULL, page_size, PROT_READ, MAP_SHARED, + self->status_fd, 0); + + /* Register should work */ + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); + ASSERT_EQ(0, reg.write_index); + ASSERT_NE(0, reg.status_index); + + /* Multiple registers should result in same index */ + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); + ASSERT_EQ(0, reg.write_index); + ASSERT_NE(0, reg.status_index); + + /* Ensure disabled */ + self->enable_fd = open(enable_file, O_RDWR); + ASSERT_NE(-1, self->enable_fd); + ASSERT_NE(-1, write(self->enable_fd, "0", sizeof("0"))) + + /* MMAP should work and be zero'd */ + ASSERT_NE(MAP_FAILED, status_page); + ASSERT_NE(NULL, status_page); + ASSERT_EQ(0, status_page[reg.status_index]); + + /* Enable event and ensure bits updated in status */ + ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1"))) + ASSERT_EQ(EVENT_STATUS_FTRACE, status_page[reg.status_index]); + + /* Disable event and ensure bits updated in status */ + ASSERT_NE(-1, write(self->enable_fd, "0", sizeof("0"))) + ASSERT_EQ(0, status_page[reg.status_index]); + + /* File still open should return -EBUSY for delete */ + ASSERT_EQ(-1, ioctl(self->data_fd, DIAG_IOCSDEL, "__test_event")); + ASSERT_EQ(EBUSY, errno); + + /* Delete should work only after close */ + close(self->data_fd); + self->data_fd = open(data_file, O_RDWR); + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSDEL, "__test_event")); + + /* Unmap should work */ + ASSERT_EQ(0, munmap(status_page, page_size)); +} + +TEST_F(user, write_events) { + struct user_reg reg = {0}; + struct iovec io[3]; + __u32 field1, field2; + int before = 0, after = 0; + + reg.size = sizeof(reg); + reg.name_args = (__u64)"__test_event u32 field1; u32 field2"; + + field1 = 1; + field2 = 2; + + io[0].iov_base = ®.write_index; + io[0].iov_len = sizeof(reg.write_index); + io[1].iov_base = &field1; + io[1].iov_len = sizeof(field1); + io[2].iov_base = &field2; + io[2].iov_len = sizeof(field2); + + /* Register should work */ + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); + ASSERT_EQ(0, reg.write_index); + ASSERT_NE(0, reg.status_index); + + /* Write should fail on invalid slot with ENOENT */ + io[0].iov_base = &field2; + io[0].iov_len = sizeof(field2); + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(ENOENT, errno); + io[0].iov_base = ®.write_index; + io[0].iov_len = sizeof(reg.write_index); + + /* Enable event */ + self->enable_fd = open(enable_file, O_RDWR); + ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1"))) + + /* Write should make it out to ftrace buffers */ + before = trace_bytes(); + ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + after = trace_bytes(); + ASSERT_GT(after, before); +} + +TEST_F(user, write_fault) { + struct user_reg reg = {0}; + struct iovec io[2]; + int l = sizeof(__u64); + void *anon; + + reg.size = sizeof(reg); + reg.name_args = (__u64)"__test_event u64 anon"; + + anon = mmap(NULL, l, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + ASSERT_NE(MAP_FAILED, anon); + + io[0].iov_base = ®.write_index; + io[0].iov_len = sizeof(reg.write_index); + io[1].iov_base = anon; + io[1].iov_len = l; + + /* Register should work */ + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); + ASSERT_EQ(0, reg.write_index); + ASSERT_NE(0, reg.status_index); + + /* Write should work normally */ + ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 2)); + + /* Faulted data should zero fill and work */ + ASSERT_EQ(0, madvise(anon, l, MADV_DONTNEED)); + ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 2)); + ASSERT_EQ(0, munmap(anon, l)); +} + +TEST_F(user, write_validator) { + struct user_reg reg = {0}; + struct iovec io[3]; + int loc, bytes; + char data[8]; + int before = 0, after = 0; + + reg.size = sizeof(reg); + reg.name_args = (__u64)"__test_event __rel_loc char[] data"; + + /* Register should work */ + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); + ASSERT_EQ(0, reg.write_index); + ASSERT_NE(0, reg.status_index); + + io[0].iov_base = ®.write_index; + io[0].iov_len = sizeof(reg.write_index); + io[1].iov_base = &loc; + io[1].iov_len = sizeof(loc); + io[2].iov_base = data; + bytes = snprintf(data, sizeof(data), "Test") + 1; + io[2].iov_len = bytes; + + /* Undersized write should fail */ + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 1)); + ASSERT_EQ(EINVAL, errno); + + /* Enable event */ + self->enable_fd = open(enable_file, O_RDWR); + ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1"))) + + /* Full in-bounds write should work */ + before = trace_bytes(); + loc = DYN_LOC(0, bytes); + ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + after = trace_bytes(); + ASSERT_GT(after, before); + + /* Out of bounds write should fault (offset way out) */ + loc = DYN_LOC(1024, bytes); + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(EFAULT, errno); + + /* Out of bounds write should fault (offset 1 byte out) */ + loc = DYN_LOC(1, bytes); + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(EFAULT, errno); + + /* Out of bounds write should fault (size way out) */ + loc = DYN_LOC(0, bytes + 1024); + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(EFAULT, errno); + + /* Out of bounds write should fault (size 1 byte out) */ + loc = DYN_LOC(0, bytes + 1); + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(EFAULT, errno); + + /* Non-Null should fault */ + memset(data, 'A', sizeof(data)); + loc = DYN_LOC(0, bytes); + ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3)); + ASSERT_EQ(EFAULT, errno); +} + +TEST_F(user, print_fmt) { + int ret; + + ret = check_print_fmt("__test_event __rel_loc char[] data", + "print fmt: \"data=%s\", __get_rel_str(data)"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event __data_loc char[] data", + "print fmt: \"data=%s\", __get_str(data)"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event s64 data", + "print fmt: \"data=%lld\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event u64 data", + "print fmt: \"data=%llu\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event s32 data", + "print fmt: \"data=%d\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event u32 data", + "print fmt: \"data=%u\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event int data", + "print fmt: \"data=%d\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event unsigned int data", + "print fmt: \"data=%u\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event s16 data", + "print fmt: \"data=%d\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event u16 data", + "print fmt: \"data=%u\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event short data", + "print fmt: \"data=%d\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event unsigned short data", + "print fmt: \"data=%u\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event s8 data", + "print fmt: \"data=%d\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event u8 data", + "print fmt: \"data=%u\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event char data", + "print fmt: \"data=%d\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event unsigned char data", + "print fmt: \"data=%u\", REC->data"); + ASSERT_EQ(0, ret); + + ret = check_print_fmt("__test_event char[4] data", + "print fmt: \"data=%s\", REC->data"); + ASSERT_EQ(0, ret); +} + +int main(int argc, char **argv) +{ + return test_harness_run(argc, argv); +} diff --git a/tools/testing/selftests/user_events/perf_test.c b/tools/testing/selftests/user_events/perf_test.c new file mode 100644 index 0000000..26851d5 --- /dev/null +++ b/tools/testing/selftests/user_events/perf_test.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * User Events Perf Events Test Program + * + * Copyright (c) 2021 Beau Belgrave + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest_harness.h" + +const char *data_file = "/sys/kernel/debug/tracing/user_events_data"; +const char *status_file = "/sys/kernel/debug/tracing/user_events_status"; +const char *id_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/id"; +const char *fmt_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/format"; + +struct event { + __u32 index; + __u32 field1; + __u32 field2; +}; + +static long perf_event_open(struct perf_event_attr *pe, pid_t pid, + int cpu, int group_fd, unsigned long flags) +{ + return syscall(__NR_perf_event_open, pe, pid, cpu, group_fd, flags); +} + +static int get_id(void) +{ + FILE *fp = fopen(id_file, "r"); + int ret, id = 0; + + if (!fp) + return -1; + + ret = fscanf(fp, "%d", &id); + fclose(fp); + + if (ret != 1) + return -1; + + return id; +} + +static int get_offset(void) +{ + FILE *fp = fopen(fmt_file, "r"); + int ret, c, last = 0, offset = 0; + + if (!fp) + return -1; + + /* Read until empty line */ + while (true) { + c = getc(fp); + + if (c == EOF) + break; + + if (last == '\n' && c == '\n') + break; + + last = c; + } + + ret = fscanf(fp, "\tfield:u32 field1;\toffset:%d;", &offset); + fclose(fp); + + if (ret != 1) + return -1; + + return offset; +} + +FIXTURE(user) { + int status_fd; + int data_fd; +}; + +FIXTURE_SETUP(user) { + self->status_fd = open(status_file, O_RDONLY); + ASSERT_NE(-1, self->status_fd); + + self->data_fd = open(data_file, O_RDWR); + ASSERT_NE(-1, self->data_fd); +} + +FIXTURE_TEARDOWN(user) { + close(self->status_fd); + close(self->data_fd); +} + +TEST_F(user, perf_write) { + struct perf_event_attr pe = {0}; + struct user_reg reg = {0}; + int page_size = sysconf(_SC_PAGESIZE); + char *status_page; + struct event event; + struct perf_event_mmap_page *perf_page; + int id, fd, offset; + __u32 *val; + + reg.size = sizeof(reg); + reg.name_args = (__u64)"__test_event u32 field1; u32 field2"; + + status_page = mmap(NULL, page_size, PROT_READ, MAP_SHARED, + self->status_fd, 0); + ASSERT_NE(MAP_FAILED, status_page); + + /* Register should work */ + ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); + ASSERT_EQ(0, reg.write_index); + ASSERT_NE(0, reg.status_index); + ASSERT_EQ(0, status_page[reg.status_index]); + + /* Id should be there */ + id = get_id(); + ASSERT_NE(-1, id); + offset = get_offset(); + ASSERT_NE(-1, offset); + + pe.type = PERF_TYPE_TRACEPOINT; + pe.size = sizeof(pe); + pe.config = id; + pe.sample_type = PERF_SAMPLE_RAW; + pe.sample_period = 1; + pe.wakeup_events = 1; + + /* Tracepoint attach should work */ + fd = perf_event_open(&pe, 0, -1, -1, 0); + ASSERT_NE(-1, fd); + + perf_page = mmap(NULL, page_size * 2, PROT_READ, MAP_SHARED, fd, 0); + ASSERT_NE(MAP_FAILED, perf_page); + + /* Status should be updated */ + ASSERT_EQ(EVENT_STATUS_PERF, status_page[reg.status_index]); + + event.index = reg.write_index; + event.field1 = 0xc001; + event.field2 = 0xc01a; + + /* Ensure write shows up at correct offset */ + ASSERT_NE(-1, write(self->data_fd, &event, sizeof(event))); + val = (void *)(((char *)perf_page) + perf_page->data_offset); + ASSERT_EQ(PERF_RECORD_SAMPLE, *val); + /* Skip over header and size, move to offset */ + val += 3; + val = (void *)((char *)val) + offset; + /* Ensure correct */ + ASSERT_EQ(event.field1, *val++); + ASSERT_EQ(event.field2, *val++); +} + +int main(int argc, char **argv) +{ + return test_harness_run(argc, argv); +} diff --git a/tools/testing/selftests/user_events/settings b/tools/testing/selftests/user_events/settings new file mode 100644 index 0000000..ba4d85f --- /dev/null +++ b/tools/testing/selftests/user_events/settings @@ -0,0 +1 @@ +timeout=90