tsacct: fix bacct_add_tsk()'s use of do_div()

3e85ba03 · David Howells <[email protected]> · 2008-07-25 01:48:50 -07:00

Fix bacct_add_tsk()'s use of do_div() on an s64 by making ac_etime a u64
instead and dividing that.

Possibly this should be guarded lest the interval calculation turn up
negative, but the possible negativity of the result of the division is
cast away, and it shouldn't end up negative anyway.

This was introduced by patch f3cef7a99469afc159fec3a61b42dc7ca5b6824f.

Signed-off-by: David Howells <[email protected]>
Cc: Jay Lan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Commit: 3e85ba034deec351f02cb55ff225bbd616463841
Parents: 297c5d92

Changes

1 files changed · +2 −2

File	Status	Add	Del	Content
kernel/tsacct.c	modified	+2	−2	View file

kernel/tsacct.c

View file

diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 1da6990..3da47cc 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -28,14 +28,14 @@
 void bacct_add_tsk(struct taskstats *stats, struct task_struct *tsk)
 {
 	struct timespec uptime, ts;
-	s64 ac_etime;
+	u64 ac_etime;
 
 	BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
 
 	/* calculate task elapsed time in timespec */
 	do_posix_clock_monotonic_gettime(&uptime);
 	ts = timespec_sub(uptime, tsk->start_time);
-	/* rebase elapsed time to usec */
+	/* rebase elapsed time to usec (should never be negative) */
 	ac_etime = timespec_to_ns(&ts);
 	do_div(ac_etime, NSEC_PER_USEC);
 	stats->ac_etime = ac_etime;