[RFC,PATCH 1/2] cputimers/proc: do_task_stat()->task_times() can race with getrusage()
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From: Oleg Nesterov on 24 Mar 2010 16:50 do_task_stat()->task_times() can race with getrusage(), they both can try to update task->prev_Xtime at the same time. Remove this bit of d180c5bc "sched: Introduce task_times() to replace task_{u,s}time()". See also the next patch. Signed-off-by: Oleg Nesterov <oleg(a)redhat.com> --- fs/proc/array.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- 34-rc1/fs/proc/array.c~PROC_4_DTS_TASK_TIMES_IS_RACY 2010-03-24 19:53:23.000000000 +0100 +++ 34-rc1/fs/proc/array.c 2010-03-24 19:57:37.000000000 +0100 @@ -449,7 +449,8 @@ static int do_task_stat(struct seq_file if (!whole) { min_flt = task->min_flt; maj_flt = task->maj_flt; - task_times(task, &utime, &stime); + utime = task->utime; + stime = task->stime; gtime = task->gtime; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |