> 在 2016年6月14日,下午4:56,Ingo Molnar <mi...@kernel.org> 写道: > > > * WANG Chao <wcw...@gmail.com> wrote: > >> unlikely() was dropped in commit ce03e4137bb2 ("sched/core: Drop >> unlikely behind BUG_ON()"), but commit 29d6455178a0 ("sched: panic on >> corrupted stack end") dropped BUG_ON() and called panic directly. >> >> Now we should bring unlikely() back for branch prediction. While we're >> at it, it's better and cleaner to turn task_stack_end_corrupted() into >> inline function. >> >> Signed-off-by: WANG Chao <wcw...@gmail.com> >> --- >> include/linux/sched.h | 7 +++++-- >> 1 file changed, 5 insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/sched.h b/include/linux/sched.h >> index 6e42ada26345..797ca1975431 100644 >> --- a/include/linux/sched.h >> +++ b/include/linux/sched.h >> @@ -2997,8 +2997,11 @@ static inline unsigned long *end_of_stack(struct >> task_struct *p) >> } >> >> #endif >> -#define task_stack_end_corrupted(task) \ >> - (*(end_of_stack(task)) != STACK_END_MAGIC) >> + >> +static inline int task_stack_end_corrupted(struct task_struct *p) >> +{ >> + return unlikely(*(end_of_stack(p)) != STACK_END_MAGIC); >> +} > > The passed in pointer should be const, and the extra parentheses around the > end_of_stack() call are not needed anymore (since it's now proper C code now).
end_of_stack() will discard const and cause an compiler warning. Should I add const to end_of_stack()?