diff options
| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2007-10-17 08:25:43 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-17 17:42:44 +0200 |
| commit | 252e0ba6b77dcfae448fa2fbaf796e8a83839e75 (patch) | |
| tree | f21bcd6994b65ba947b41ae7d2519a960185a029 | |
| parent | lib: percpu_counter_sub (diff) | |
| download | linux-252e0ba6b77dcfae448fa2fbaf796e8a83839e75.tar.xz linux-252e0ba6b77dcfae448fa2fbaf796e8a83839e75.zip | |
lib: percpu_counter variable batch
Because the current batch setup has an quadric error bound on the counter,
allow for an alternative setup.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/percpu_counter.h | 10 | ||||
| -rw-r--r-- | lib/percpu_counter.c | 6 |
2 files changed, 12 insertions, 4 deletions
diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h index 438a170187ec..40df86f7a3b4 100644 --- a/include/linux/percpu_counter.h +++ b/include/linux/percpu_counter.h @@ -32,9 +32,14 @@ struct percpu_counter { void percpu_counter_init(struct percpu_counter *fbc, s64 amount); void percpu_counter_destroy(struct percpu_counter *fbc); -void percpu_counter_add(struct percpu_counter *fbc, s32 amount); +void __percpu_counter_add(struct percpu_counter *fbc, s32 amount, s32 batch); s64 percpu_counter_sum(struct percpu_counter *fbc); +static inline void percpu_counter_add(struct percpu_counter *fbc, s32 amount) +{ + __percpu_counter_add(fbc, amount, FBC_BATCH); +} + static inline s64 percpu_counter_read(struct percpu_counter *fbc) { return fbc->count; @@ -70,6 +75,9 @@ static inline void percpu_counter_destroy(struct percpu_counter *fbc) { } +#define __percpu_counter_add(fbc, amount, batch) \ + percpu_counter_add(fbc, amount) + static inline void percpu_counter_add(struct percpu_counter *fbc, s32 amount) { diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index 5f36ad79a24a..f736d67c64d7 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -14,7 +14,7 @@ static LIST_HEAD(percpu_counters); static DEFINE_MUTEX(percpu_counters_lock); #endif -void percpu_counter_add(struct percpu_counter *fbc, s32 amount) +void __percpu_counter_add(struct percpu_counter *fbc, s32 amount, s32 batch) { long count; s32 *pcount; @@ -22,7 +22,7 @@ void percpu_counter_add(struct percpu_counter *fbc, s32 amount) pcount = per_cpu_ptr(fbc->counters, cpu); count = *pcount + amount; - if (count >= FBC_BATCH || count <= -FBC_BATCH) { + if (count >= batch || count <= -batch) { spin_lock(&fbc->lock); fbc->count += count; *pcount = 0; @@ -32,7 +32,7 @@ void percpu_counter_add(struct percpu_counter *fbc, s32 amount) } put_cpu(); } -EXPORT_SYMBOL(percpu_counter_add); +EXPORT_SYMBOL(__percpu_counter_add); /* * Add up all the per-cpu counts, return the result. This is a more accurate |