diff options
Diffstat (limited to 'mm/mm_init.c')
| -rw-r--r-- | mm/mm_init.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/mm/mm_init.c b/mm/mm_init.c index 435e5f794b3b..b06a30fbedff 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -13,6 +13,7 @@ #include <linux/memory.h> #include <linux/notifier.h> #include <linux/sched.h> +#include <linux/mman.h> #include "internal.h" #ifdef CONFIG_DEBUG_MEMORY_INIT @@ -144,14 +145,23 @@ EXPORT_SYMBOL_GPL(mm_kobj); #ifdef CONFIG_SMP s32 vm_committed_as_batch = 32; -static void __meminit mm_compute_batch(void) +void mm_compute_batch(int overcommit_policy) { u64 memsized_batch; s32 nr = num_present_cpus(); s32 batch = max_t(s32, nr*2, 32); - - /* batch size set to 0.4% of (total memory/#cpus), or max int32 */ - memsized_batch = min_t(u64, (totalram_pages()/nr)/256, 0x7fffffff); + unsigned long ram_pages = totalram_pages(); + + /* + * For policy OVERCOMMIT_NEVER, set batch size to 0.4% of + * (total memory/#cpus), and lift it to 25% for other policies + * to easy the possible lock contention for percpu_counter + * vm_committed_as, while the max limit is INT_MAX + */ + if (overcommit_policy == OVERCOMMIT_NEVER) + memsized_batch = min_t(u64, ram_pages/nr/256, INT_MAX); + else + memsized_batch = min_t(u64, ram_pages/nr/4, INT_MAX); vm_committed_as_batch = max_t(s32, memsized_batch, batch); } @@ -162,7 +172,7 @@ static int __meminit mm_compute_batch_notifier(struct notifier_block *self, switch (action) { case MEM_ONLINE: case MEM_OFFLINE: - mm_compute_batch(); + mm_compute_batch(sysctl_overcommit_memory); default: break; } @@ -176,7 +186,7 @@ static struct notifier_block compute_batch_nb __meminitdata = { static int __init mm_compute_batch_init(void) { - mm_compute_batch(); + mm_compute_batch(sysctl_overcommit_memory); register_hotmemory_notifier(&compute_batch_nb); return 0; |