Commit 4b48512c authored Nov 11, 2019 by Jiri Slaby Committed by Ingo Molnar Nov 11, 2019

stacktrace: Get rid of unneeded '!!' pattern



My commit b0c51f15 ("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>

parent 31f4f5b4

kernel/stacktrace.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -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);

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