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authorPaolo Bonzini <pbonzini@redhat.com>2019-08-09 16:53:39 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2019-08-09 16:53:39 +0200
commit0e1c438c44dd9cde56effb44c5f1cfeda72e108d (patch)
treefa3492d4d7d8b7444e5d8ebe6c78210826333e4b /lib/percpu-refcount.c
parentc096397c78f766db972f923433031f2dec01cae0 (diff)
parentcdb2d3ee0436d74fa9092f2df46aaa6f9e03c969 (diff)
Merge tag 'kvmarm-fixes-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm fixes for 5.3 - A bunch of switch/case fall-through annotation, fixing one actual bug - Fix PMU reset bug - Add missing exception class debug strings
Diffstat (limited to 'lib/percpu-refcount.c')
-rw-r--r--lib/percpu-refcount.c13
1 files changed, 11 insertions, 2 deletions
diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c
index 071a76c7bac07..4f6c6ebbbbdea 100644
--- a/lib/percpu-refcount.c
+++ b/lib/percpu-refcount.c
@@ -70,11 +70,14 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release,
return -ENOMEM;
ref->force_atomic = flags & PERCPU_REF_INIT_ATOMIC;
+ ref->allow_reinit = flags & PERCPU_REF_ALLOW_REINIT;
- if (flags & (PERCPU_REF_INIT_ATOMIC | PERCPU_REF_INIT_DEAD))
+ if (flags & (PERCPU_REF_INIT_ATOMIC | PERCPU_REF_INIT_DEAD)) {
ref->percpu_count_ptr |= __PERCPU_REF_ATOMIC;
- else
+ ref->allow_reinit = true;
+ } else {
start_count += PERCPU_COUNT_BIAS;
+ }
if (flags & PERCPU_REF_INIT_DEAD)
ref->percpu_count_ptr |= __PERCPU_REF_DEAD;
@@ -120,6 +123,9 @@ static void percpu_ref_call_confirm_rcu(struct rcu_head *rcu)
ref->confirm_switch = NULL;
wake_up_all(&percpu_ref_switch_waitq);
+ if (!ref->allow_reinit)
+ percpu_ref_exit(ref);
+
/* drop ref from percpu_ref_switch_to_atomic() */
percpu_ref_put(ref);
}
@@ -195,6 +201,9 @@ static void __percpu_ref_switch_to_percpu(struct percpu_ref *ref)
if (!(ref->percpu_count_ptr & __PERCPU_REF_ATOMIC))
return;
+ if (WARN_ON_ONCE(!ref->allow_reinit))
+ return;
+
atomic_long_add(PERCPU_COUNT_BIAS, &ref->count);
/*