openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

stacktrace: Get rid of unneeded '!!' pattern 

My commit b0c51f1584 ("stacktrace: Don't skip first entry on
noncurrent tasks") adds one or zero to skipnr by "!!(current == tsk)".

But the C99 standard says:

  The == (equal to) and != (not equal to) operators are
  ...
  Each of the operators yields 1 if the specified relation is true and 0
  if it is false.

So there is no need to prepend the above expression by "!!" -- remove it.

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111092647.27419-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Jiri Slaby 2019-11-11 10:26:47 +01:00 committed by Ingo Molnar
parent 31f4f5b495
commit 4b48512c2e
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/stacktrace.c
View File

@ -142,7 +142,7 @@ unsigned int stack_trace_save_tsk(struct task_struct *tsk, unsigned long *store,
.store = store,
.size = size,
/* skip this function if they are tracing us */
.skip = skipnr + !!(current == tsk),
.skip = skipnr + (current == tsk),
};
if (!try_get_task_stack(tsk))
@ -300,7 +300,7 @@ unsigned int stack_trace_save_tsk(struct task_struct *task,
.entries = store,
.max_entries = size,
/* skip this function if they are tracing us */
.skip = skipnr + !!(current == task),
.skip = skipnr + (current == task),
};
save_stack_trace_tsk(task, &trace);