Commit 8ab2b7ef authored Apr 21, 2011 by Steven Rostedt Committed by Steven Rostedt Apr 29, 2011

ftrace: Remove unnecessary disabling of irqs



The disabling of interrupts around ftrace_update_code() was used
to protect against the evil ftrace daemon from years past. But that
daemon has long been killed. It is safe to keep interrupts enabled
while updating the initial mcount into nops.

The ftrace_mutex is also held which keeps other users at bay.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

parent 0778d9ad

kernel/trace/ftrace.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -2707,7 +2707,6 @@ static int ftrace_process_locs(struct module *mod,
		{
		unsigned long *p;
		unsigned long addr;
		unsigned long flags;

		mutex_lock(&ftrace_lock);
		p = start;
		@@ -2724,10 +2723,7 @@ static int ftrace_process_locs(struct module *mod,
		ftrace_record_ip(addr);
		}

		/* disable interrupts to prevent kstop machine */
		local_irq_save(flags);
		ftrace_update_code(mod);
		local_irq_restore(flags);
		mutex_unlock(&ftrace_lock);

		return 0;

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