summaryrefslogtreecommitdiff
path: root/lib/percpu-refcount.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/percpu-refcount.c')
-rw-r--r--lib/percpu-refcount.c56
1 files changed, 29 insertions, 27 deletions
diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c
index 8ef3f5c20df6..5aea6b7356c7 100644
--- a/lib/percpu-refcount.c
+++ b/lib/percpu-refcount.c
@@ -11,8 +11,8 @@
* percpu counters will all sum to the correct value
*
* (More precisely: because moduler arithmatic is commutative the sum of all the
- * pcpu_count vars will be equal to what it would have been if all the gets and
- * puts were done to a single integer, even if some of the percpu integers
+ * percpu_count vars will be equal to what it would have been if all the gets
+ * and puts were done to a single integer, even if some of the percpu integers
* overflow or underflow).
*
* The real trick to implementing percpu refcounts is shutdown. We can't detect
@@ -29,11 +29,12 @@
* atomic_long_t can't hit 0 before we've added up all the percpu refs.
*/
-#define PCPU_COUNT_BIAS (1LU << (BITS_PER_LONG - 1))
+#define PERCPU_COUNT_BIAS (1LU << (BITS_PER_LONG - 1))
-static unsigned long __percpu *pcpu_count_ptr(struct percpu_ref *ref)
+static unsigned long __percpu *percpu_count_ptr(struct percpu_ref *ref)
{
- return (unsigned long __percpu *)(ref->pcpu_count_ptr & ~PCPU_REF_DEAD);
+ return (unsigned long __percpu *)
+ (ref->percpu_count_ptr & ~__PERCPU_REF_DEAD);
}
/**
@@ -51,10 +52,11 @@ static unsigned long __percpu *pcpu_count_ptr(struct percpu_ref *ref)
int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release,
gfp_t gfp)
{
- atomic_long_set(&ref->count, 1 + PCPU_COUNT_BIAS);
+ atomic_long_set(&ref->count, 1 + PERCPU_COUNT_BIAS);
- ref->pcpu_count_ptr = (unsigned long)alloc_percpu_gfp(unsigned long, gfp);
- if (!ref->pcpu_count_ptr)
+ ref->percpu_count_ptr =
+ (unsigned long)alloc_percpu_gfp(unsigned long, gfp);
+ if (!ref->percpu_count_ptr)
return -ENOMEM;
ref->release = release;
@@ -74,11 +76,11 @@ EXPORT_SYMBOL_GPL(percpu_ref_init);
*/
void percpu_ref_exit(struct percpu_ref *ref)
{
- unsigned long __percpu *pcpu_count = pcpu_count_ptr(ref);
+ unsigned long __percpu *percpu_count = percpu_count_ptr(ref);
- if (pcpu_count) {
- free_percpu(pcpu_count);
- ref->pcpu_count_ptr = PCPU_REF_DEAD;
+ if (percpu_count) {
+ free_percpu(percpu_count);
+ ref->percpu_count_ptr = __PERCPU_REF_DEAD;
}
}
EXPORT_SYMBOL_GPL(percpu_ref_exit);
@@ -86,14 +88,14 @@ EXPORT_SYMBOL_GPL(percpu_ref_exit);
static void percpu_ref_kill_rcu(struct rcu_head *rcu)
{
struct percpu_ref *ref = container_of(rcu, struct percpu_ref, rcu);
- unsigned long __percpu *pcpu_count = pcpu_count_ptr(ref);
+ unsigned long __percpu *percpu_count = percpu_count_ptr(ref);
unsigned long count = 0;
int cpu;
for_each_possible_cpu(cpu)
- count += *per_cpu_ptr(pcpu_count, cpu);
+ count += *per_cpu_ptr(percpu_count, cpu);
- pr_debug("global %ld pcpu %ld",
+ pr_debug("global %ld percpu %ld",
atomic_long_read(&ref->count), (long)count);
/*
@@ -108,7 +110,7 @@ static void percpu_ref_kill_rcu(struct rcu_head *rcu)
* reaching 0 before we add the percpu counts. But doing it at the same
* time is equivalent and saves us atomic operations:
*/
- atomic_long_add((long)count - PCPU_COUNT_BIAS, &ref->count);
+ atomic_long_add((long)count - PERCPU_COUNT_BIAS, &ref->count);
WARN_ONCE(atomic_long_read(&ref->count) <= 0,
"percpu ref (%pf) <= 0 (%ld) after killed",
@@ -143,10 +145,10 @@ static void percpu_ref_kill_rcu(struct rcu_head *rcu)
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,
+ WARN_ONCE(ref->percpu_count_ptr & __PERCPU_REF_DEAD,
"%s called more than once on %pf!", __func__, ref->release);
- ref->pcpu_count_ptr |= PCPU_REF_DEAD;
+ ref->percpu_count_ptr |= __PERCPU_REF_DEAD;
ref->confirm_kill = confirm_kill;
call_rcu_sched(&ref->rcu, percpu_ref_kill_rcu);
@@ -166,24 +168,24 @@ EXPORT_SYMBOL_GPL(percpu_ref_kill_and_confirm);
*/
void percpu_ref_reinit(struct percpu_ref *ref)
{
- unsigned long __percpu *pcpu_count = pcpu_count_ptr(ref);
+ unsigned long __percpu *percpu_count = percpu_count_ptr(ref);
int cpu;
- BUG_ON(!pcpu_count);
+ BUG_ON(!percpu_count);
WARN_ON_ONCE(!percpu_ref_is_zero(ref));
- atomic_long_set(&ref->count, 1 + PCPU_COUNT_BIAS);
+ atomic_long_set(&ref->count, 1 + PERCPU_COUNT_BIAS);
/*
* Restore per-cpu operation. smp_store_release() is paired with
- * smp_read_barrier_depends() in __pcpu_ref_alive() and guarantees
- * that the zeroing is visible to all percpu accesses which can see
- * the following PCPU_REF_DEAD clearing.
+ * smp_read_barrier_depends() in __percpu_ref_alive() and
+ * guarantees that the zeroing is visible to all percpu accesses
+ * which can see the following __PERCPU_REF_DEAD clearing.
*/
for_each_possible_cpu(cpu)
- *per_cpu_ptr(pcpu_count, cpu) = 0;
+ *per_cpu_ptr(percpu_count, cpu) = 0;
- smp_store_release(&ref->pcpu_count_ptr,
- ref->pcpu_count_ptr & ~PCPU_REF_DEAD);
+ smp_store_release(&ref->percpu_count_ptr,
+ ref->percpu_count_ptr & ~__PERCPU_REF_DEAD);
}
EXPORT_SYMBOL_GPL(percpu_ref_reinit);