diff options
-rw-r--r-- | lib/Makefile | 1 | ||||
-rw-r--r-- | lib/percpu_counter.c | 46 | ||||
-rw-r--r-- | mm/swap.c | 42 |
3 files changed, 47 insertions, 42 deletions
diff --git a/lib/Makefile b/lib/Makefile index b830c9a15541..79358ad1f113 100644 --- a/lib/Makefile +++ b/lib/Makefile | |||
@@ -46,6 +46,7 @@ obj-$(CONFIG_TEXTSEARCH) += textsearch.o | |||
46 | obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o | 46 | obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o |
47 | obj-$(CONFIG_TEXTSEARCH_BM) += ts_bm.o | 47 | obj-$(CONFIG_TEXTSEARCH_BM) += ts_bm.o |
48 | obj-$(CONFIG_TEXTSEARCH_FSM) += ts_fsm.o | 48 | obj-$(CONFIG_TEXTSEARCH_FSM) += ts_fsm.o |
49 | obj-$(CONFIG_SMP) += percpu_counter.o | ||
49 | 50 | ||
50 | obj-$(CONFIG_SWIOTLB) += swiotlb.o | 51 | obj-$(CONFIG_SWIOTLB) += swiotlb.o |
51 | 52 | ||
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c new file mode 100644 index 000000000000..7a87003f8e8f --- /dev/null +++ b/lib/percpu_counter.c | |||
@@ -0,0 +1,46 @@ | |||
1 | /* | ||
2 | * Fast batching percpu counters. | ||
3 | */ | ||
4 | |||
5 | #include <linux/percpu_counter.h> | ||
6 | #include <linux/module.h> | ||
7 | |||
8 | void percpu_counter_mod(struct percpu_counter *fbc, long amount) | ||
9 | { | ||
10 | long count; | ||
11 | long *pcount; | ||
12 | int cpu = get_cpu(); | ||
13 | |||
14 | pcount = per_cpu_ptr(fbc->counters, cpu); | ||
15 | count = *pcount + amount; | ||
16 | if (count >= FBC_BATCH || count <= -FBC_BATCH) { | ||
17 | spin_lock(&fbc->lock); | ||
18 | fbc->count += count; | ||
19 | *pcount = 0; | ||
20 | spin_unlock(&fbc->lock); | ||
21 | } else { | ||
22 | *pcount = count; | ||
23 | } | ||
24 | put_cpu(); | ||
25 | } | ||
26 | EXPORT_SYMBOL(percpu_counter_mod); | ||
27 | |||
28 | /* | ||
29 | * Add up all the per-cpu counts, return the result. This is a more accurate | ||
30 | * but much slower version of percpu_counter_read_positive() | ||
31 | */ | ||
32 | long percpu_counter_sum(struct percpu_counter *fbc) | ||
33 | { | ||
34 | long ret; | ||
35 | int cpu; | ||
36 | |||
37 | spin_lock(&fbc->lock); | ||
38 | ret = fbc->count; | ||
39 | for_each_possible_cpu(cpu) { | ||
40 | long *pcount = per_cpu_ptr(fbc->counters, cpu); | ||
41 | ret += *pcount; | ||
42 | } | ||
43 | spin_unlock(&fbc->lock); | ||
44 | return ret < 0 ? 0 : ret; | ||
45 | } | ||
46 | EXPORT_SYMBOL(percpu_counter_sum); | ||
@@ -480,48 +480,6 @@ static int cpu_swap_callback(struct notifier_block *nfb, | |||
480 | #endif /* CONFIG_HOTPLUG_CPU */ | 480 | #endif /* CONFIG_HOTPLUG_CPU */ |
481 | #endif /* CONFIG_SMP */ | 481 | #endif /* CONFIG_SMP */ |
482 | 482 | ||
483 | #ifdef CONFIG_SMP | ||
484 | void percpu_counter_mod(struct percpu_counter *fbc, long amount) | ||
485 | { | ||
486 | long count; | ||
487 | long *pcount; | ||
488 | int cpu = get_cpu(); | ||
489 | |||
490 | pcount = per_cpu_ptr(fbc->counters, cpu); | ||
491 | count = *pcount + amount; | ||
492 | if (count >= FBC_BATCH || count <= -FBC_BATCH) { | ||
493 | spin_lock(&fbc->lock); | ||
494 | fbc->count += count; | ||
495 | *pcount = 0; | ||
496 | spin_unlock(&fbc->lock); | ||
497 | } else { | ||
498 | *pcount = count; | ||
499 | } | ||
500 | put_cpu(); | ||
501 | } | ||
502 | EXPORT_SYMBOL(percpu_counter_mod); | ||
503 | |||
504 | /* | ||
505 | * Add up all the per-cpu counts, return the result. This is a more accurate | ||
506 | * but much slower version of percpu_counter_read_positive() | ||
507 | */ | ||
508 | long percpu_counter_sum(struct percpu_counter *fbc) | ||
509 | { | ||
510 | long ret; | ||
511 | int cpu; | ||
512 | |||
513 | spin_lock(&fbc->lock); | ||
514 | ret = fbc->count; | ||
515 | for_each_possible_cpu(cpu) { | ||
516 | long *pcount = per_cpu_ptr(fbc->counters, cpu); | ||
517 | ret += *pcount; | ||
518 | } | ||
519 | spin_unlock(&fbc->lock); | ||
520 | return ret < 0 ? 0 : ret; | ||
521 | } | ||
522 | EXPORT_SYMBOL(percpu_counter_sum); | ||
523 | #endif | ||
524 | |||
525 | /* | 483 | /* |
526 | * Perform any setup for the swap system | 484 | * Perform any setup for the swap system |
527 | */ | 485 | */ |