tracing/branch-tracer: fix a trace recursion on branch tracer

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Impact: fix crash when enabling the branch-tracer

When the branch tracer inserts an event through
probe_likely_condition(), it calls local_irq_save() and then results
in a trace recursion.

local_irq_save() -> trace_hardirqs_off() -> trace_hardirqs_off_caller()
	-> unlikely()

The trace_branch.c file is protected by DISABLE_BRANCH_PROFILING but
that doesn't prevent from external call to functions that use
unlikely().

My box crashed each time I tried to set this tracer (sudden and hard
reboot).

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

...

This commit is contained in:

Frederic Weisbecker 2008-11-16 05:59:52 +01:00 • committed by Ingo Molnar

parent c91add5fa6

commit 072b40a156

1 changed files with 2 additions and 2 deletions

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kernel/trace/trace_branch.c

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