percpu-refcount: improve WARN messages

percpu_ref's WARN messages can be a lot more helpful by indicating
who's the culprit.  Make them report the release function that the
offending percpu-refcount is associated with.  This should make it a
lot easier to track down the reported invalid refcnting operations.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
This commit is contained in:
Tejun Heo 2014-09-20 01:27:24 -04:00
parent 23cb8981ed
commit 4843c3320c
1 changed files with 5 additions and 3 deletions

View File

@ -145,8 +145,9 @@ static void percpu_ref_kill_rcu(struct rcu_head *rcu)
atomic_add((int) count - PCPU_COUNT_BIAS, &ref->count);
WARN_ONCE(atomic_read(&ref->count) <= 0, "percpu ref <= 0 (%i)",
atomic_read(&ref->count));
WARN_ONCE(atomic_read(&ref->count) <= 0,
"percpu ref (%pf) <= 0 (%i) after killed",
ref->release, atomic_read(&ref->count));
/* @ref is viewed as dead on all CPUs, send out kill confirmation */
if (ref->confirm_kill)
@ -178,7 +179,8 @@ void percpu_ref_kill_and_confirm(struct percpu_ref *ref,
percpu_ref_func_t *confirm_kill)
{
WARN_ONCE(ref->pcpu_count_ptr & PCPU_REF_DEAD,
"percpu_ref_kill() called more than once!\n");
"percpu_ref_kill() called more than once on %pf!",
ref->release);
ref->pcpu_count_ptr |= PCPU_REF_DEAD;
ref->confirm_kill = confirm_kill;