diff options
| -rw-r--r-- | fs/ext4/ext4.h | 6 | ||||
| -rw-r--r-- | fs/ext4/inode.c | 2 | ||||
| -rw-r--r-- | include/linux/percpu_counter.h | 8 | ||||
| -rw-r--r-- | lib/percpu_counter.c | 18 |
4 files changed, 20 insertions, 14 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index b0537c82702..6c46c648430 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1225,11 +1225,11 @@ do { \ } while (0) #ifdef CONFIG_SMP -/* Each CPU can accumulate FBC_BATCH blocks in their local +/* Each CPU can accumulate percpu_counter_batch blocks in their local * counters. So we need to make sure we have free blocks more - * than FBC_BATCH * nr_cpu_ids. Also add a window of 4 times. + * than percpu_counter_batch * nr_cpu_ids. Also add a window of 4 times. */ -#define EXT4_FREEBLOCKS_WATERMARK (4 * (FBC_BATCH * nr_cpu_ids)) +#define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids)) #else #define EXT4_FREEBLOCKS_WATERMARK 0 #endif diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 6702a49992a..98d3fe7057e 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2498,7 +2498,7 @@ static int ext4_nonda_switch(struct super_block *sb) /* * switch to non delalloc mode if we are running low * on free block. The free block accounting via percpu - * counters can get slightly wrong with FBC_BATCH getting + * counters can get slightly wrong with percpu_counter_batch getting * accumulated on each CPU without updating global counters * Delalloc need an accurate free block accounting. So switch * to non delalloc when we are near to error range. diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h index 9007ccdfc11..99de7a31bab 100644 --- a/include/linux/percpu_counter.h +++ b/include/linux/percpu_counter.h @@ -24,11 +24,7 @@ struct percpu_counter { s32 *counters; }; -#if NR_CPUS >= 16 -#define FBC_BATCH (NR_CPUS*2) -#else -#define FBC_BATCH (NR_CPUS*4) -#endif +extern int percpu_counter_batch; int percpu_counter_init(struct percpu_counter *fbc, s64 amount); int percpu_counter_init_irq(struct percpu_counter *fbc, s64 amount); @@ -39,7 +35,7 @@ s64 __percpu_counter_sum(struct percpu_counter *fbc); static inline void percpu_counter_add(struct percpu_counter *fbc, s64 amount) { - __percpu_counter_add(fbc, amount, FBC_BATCH); + __percpu_counter_add(fbc, amount, percpu_counter_batch); } static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc) diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index b255b939bc1..a60bd804609 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -9,10 +9,8 @@ #include <linux/cpu.h> #include <linux/module.h> -#ifdef CONFIG_HOTPLUG_CPU static LIST_HEAD(percpu_counters); static DEFINE_MUTEX(percpu_counters_lock); -#endif void percpu_counter_set(struct percpu_counter *fbc, s64 amount) { @@ -111,13 +109,24 @@ void percpu_counter_destroy(struct percpu_counter *fbc) } EXPORT_SYMBOL(percpu_counter_destroy); -#ifdef CONFIG_HOTPLUG_CPU +int percpu_counter_batch __read_mostly = 32; +EXPORT_SYMBOL(percpu_counter_batch); + +static void compute_batch_value(void) +{ + int nr = num_online_cpus(); + + percpu_counter_batch = max(32, nr*2); +} + static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu) { +#ifdef CONFIG_HOTPLUG_CPU unsigned int cpu; struct percpu_counter *fbc; + compute_batch_value(); if (action != CPU_DEAD) return NOTIFY_OK; @@ -134,13 +143,14 @@ static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb, spin_unlock_irqrestore(&fbc->lock, flags); } mutex_unlock(&percpu_counters_lock); +#endif return NOTIFY_OK; } static int __init percpu_counter_startup(void) { + compute_batch_value(); hotcpu_notifier(percpu_counter_hotcpu_callback, 0); return 0; } module_init(percpu_counter_startup); -#endif |