diff options
| author | Dmitry Vyukov <dvyukov@google.com> | 2017-05-08 15:56:48 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-05-08 17:15:12 -0700 |
| commit | f61e869d519c0c11a8d80a503cfdfb4897df855a (patch) | |
| tree | 4befe4405314621e224b7118b42632364dc9be52 /kernel/kcov.c | |
| parent | 8c733420bdd5a6cc2d8540fb5aa32d1fbf3cb3ff (diff) | |
| download | lwn-f61e869d519c0c11a8d80a503cfdfb4897df855a.tar.gz lwn-f61e869d519c0c11a8d80a503cfdfb4897df855a.zip | |
kcov: simplify interrupt check
in_interrupt() semantics are confusing and wrong for most users as it
also returns true when bh is disabled. Thus we open coded a proper
check for interrupts in __sanitizer_cov_trace_pc() with a lengthy
explanatory comment.
Use the new in_task() predicate instead.
Link: http://lkml.kernel.org/r/20170321091026.139655-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: James Morse <james.morse@arm.com>
Cc: Alexander Popov <alex.popov@linux.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kcov.c')
| -rw-r--r-- | kernel/kcov.c | 9 |
1 files changed, 1 insertions, 8 deletions
diff --git a/kernel/kcov.c b/kernel/kcov.c index 85e5546cd791..cd771993f96f 100644 --- a/kernel/kcov.c +++ b/kernel/kcov.c @@ -60,15 +60,8 @@ void notrace __sanitizer_cov_trace_pc(void) /* * We are interested in code coverage as a function of a syscall inputs, * so we ignore code executed in interrupts. - * The checks for whether we are in an interrupt are open-coded, because - * 1. We can't use in_interrupt() here, since it also returns true - * when we are inside local_bh_disable() section. - * 2. We don't want to use (in_irq() | in_serving_softirq() | in_nmi()), - * since that leads to slower generated code (three separate tests, - * one for each of the flags). */ - if (!t || (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET - | NMI_MASK))) + if (!t || !in_task()) return; mode = READ_ONCE(t->kcov_mode); if (mode == KCOV_MODE_TRACE) { |