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sched/cputime: Refactor the cputime_adjust() code

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Address a Coverity false positive, which is caused by overly
convoluted code:

Value assigned to variable 'utime' at line 619:utime = rtime;
is overwritten at line 642:utime = rtime - stime; before it
can be used. This makes such variable assignment useless.

Remove this variable assignment and refactor the code related.

Addresses-Coverity-ID: 1371643
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Cc: Frans Klaver <fransklaver@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/20170629184128.GA5271@embeddedgus
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Gustavo A. R. Silva 2017-06-29 13:41:28 -05:00 committed by Ingo Molnar
parent 48365b3884
commit 72298e5c92
1 changed files with 5 additions and 11 deletions
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16
kernel/sched/cputime.c
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@ -615,19 +615,13 @@ static void cputime_adjust(struct task_cputime *curr,
* userspace. Once a task gets some ticks, the monotonicy code at
* 'update' will ensure things converge to the observed ratio.
*/
if (stime == 0) {
utime = rtime;
goto update;
if (stime != 0) {
if (utime == 0)
stime = rtime;
else
stime = scale_stime(stime, rtime, stime + utime);
}
if (utime == 0) {
stime = rtime;
goto update;
}
stime = scale_stime(stime, rtime, stime + utime);
update:
/*
* Make sure stime doesn't go backwards; this preserves monotonicity
* for utime because rtime is monotonic.