From fcb94f72d3e0f4f34b326c2986da8e5996daf72c Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Fri, 8 Jul 2011 14:14:38 +1000 Subject: [PATCH] inode: convert inode_stat.nr_unused to per-cpu counters Before we split up the inode_lru_lock, the unused inode counter needs to be made independent of the global inode_lru_lock. Convert it to per-cpu counters to do this. Signed-off-by: Dave Chinner Signed-off-by: Al Viro --- fs/inode.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index cbdcab88105f..9a0361121712 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -95,6 +95,7 @@ EXPORT_SYMBOL(empty_aops); struct inodes_stat_t inodes_stat; static DEFINE_PER_CPU(unsigned int, nr_inodes); +static DEFINE_PER_CPU(unsigned int, nr_unused); static struct kmem_cache *inode_cachep __read_mostly; @@ -109,7 +110,11 @@ static int get_nr_inodes(void) static inline int get_nr_inodes_unused(void) { - return inodes_stat.nr_unused; + int i; + int sum = 0; + for_each_possible_cpu(i) + sum += per_cpu(nr_unused, i); + return sum < 0 ? 0 : sum; } int get_nr_dirty_inodes(void) @@ -127,6 +132,7 @@ int proc_nr_inodes(ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { inodes_stat.nr_inodes = get_nr_inodes(); + inodes_stat.nr_unused = get_nr_inodes_unused(); return proc_dointvec(table, write, buffer, lenp, ppos); } #endif @@ -340,7 +346,7 @@ static void inode_lru_list_add(struct inode *inode) spin_lock(&inode_lru_lock); if (list_empty(&inode->i_lru)) { list_add(&inode->i_lru, &inode_lru); - inodes_stat.nr_unused++; + this_cpu_inc(nr_unused); } spin_unlock(&inode_lru_lock); } @@ -350,7 +356,7 @@ static void inode_lru_list_del(struct inode *inode) spin_lock(&inode_lru_lock); if (!list_empty(&inode->i_lru)) { list_del_init(&inode->i_lru); - inodes_stat.nr_unused--; + this_cpu_dec(nr_unused); } spin_unlock(&inode_lru_lock); } @@ -656,7 +662,7 @@ static void prune_icache(int nr_to_scan) (inode->i_state & ~I_REFERENCED)) { list_del_init(&inode->i_lru); spin_unlock(&inode->i_lock); - inodes_stat.nr_unused--; + this_cpu_dec(nr_unused); continue; } @@ -693,7 +699,7 @@ static void prune_icache(int nr_to_scan) spin_unlock(&inode->i_lock); list_move(&inode->i_lru, &freeable); - inodes_stat.nr_unused--; + this_cpu_dec(nr_unused); } if (current_is_kswapd()) __count_vm_events(KSWAPD_INODESTEAL, reap); -- 2.30.2