module: Annotate nested sleep in resolve_symbol()

Because wait_event() loops are safe vs spurious wakeups we can allow the
occasional sleep -- which ends up being very similar.

Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Peter Zijlstra 2015-02-11 15:01:13 +10:30 committed by Rusty Russell
parent ab92ebbb8e
commit d64810f561

View File

@ -1225,6 +1225,12 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
const unsigned long *crc;
int err;
/*
* The module_mutex should not be a heavily contended lock;
* if we get the occasional sleep here, we'll go an extra iteration
* in the wait_event_interruptible(), which is harmless.
*/
sched_annotate_sleep();
mutex_lock(&module_mutex);
sym = find_symbol(name, &owner, &crc,
!(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);