[02/11] percpu counter: clean up percpu_counter_sum_and_set()
in [Kernel]
|
Prev: [09/11] vfs: Add no_nrwrite_index_update writeback control flag
Next: pm_op(): usb_dev_suspend+0x0/0x10 returns -2 on USB device 8087:0020
From: Jayson R. King on 27 Feb 2010 02:30 From: Mingming Cao <cmm(a)us.ibm.com> Date: Thu Oct 9 12:50:59 2008 -0400 Subject: percpu counter: clean up percpu_counter_sum_and_set() commit 1f7c14c62ce63805f9574664a6c6de3633d4a354 upstream. percpu_counter_sum_and_set() and percpu_counter_sum() is the same except the former updates the global counter after accounting. Since we are taking the fbc->lock to calculate the precise value of the counter in percpu_counter_sum() anyway, it should simply set fbc->count too, as the percpu_counter_sum_and_set() does. This patch merges these two interfaces into one. Signed-off-by: Mingming Cao <cmm(a)us.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra(a)chello.nl> Cc: <linux-ext4(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso(a)mit.edu> Signed-off-by: Jayson R. King <dev(a)jaysonking.com> --- fs/ext4/balloc.c | 2 +- include/linux/percpu_counter.h | 12 +++--------- lib/percpu_counter.c | 8 +++----- 3 files changed, 7 insertions(+), 15 deletions(-) diff -urNp linux-2.6.27.orig/fs/ext4/balloc.c linux-2.6.27/fs/ext4/balloc.c --- linux-2.6.27.orig/fs/ext4/balloc.c 2010-02-26 14:10:41.167252303 -0600 +++ linux-2.6.27/fs/ext4/balloc.c 2010-02-26 14:18:30.811252658 -0600 @@ -1778,7 +1778,7 @@ ext4_fsblk_t ext4_has_free_blocks(struct #ifdef CONFIG_SMP if (free_blocks - root_blocks < FBC_BATCH) free_blocks = - percpu_counter_sum_and_set(&sbi->s_freeblocks_counter); + percpu_counter_sum(&sbi->s_freeblocks_counter); #endif if (free_blocks <= root_blocks) /* we don't have free space */ diff -urNp linux-2.6.27.orig/include/linux/percpu_counter.h linux-2.6.27/include/linux/percpu_counter.h --- linux-2.6.27.orig/include/linux/percpu_counter.h 2010-02-26 14:10:41.961252665 -0600 +++ linux-2.6.27/include/linux/percpu_counter.h 2010-02-26 14:18:30.811252658 -0600 @@ -35,7 +35,7 @@ int percpu_counter_init_irq(struct percp void percpu_counter_destroy(struct percpu_counter *fbc); void percpu_counter_set(struct percpu_counter *fbc, s64 amount); void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch); -s64 __percpu_counter_sum(struct percpu_counter *fbc, int set); +s64 __percpu_counter_sum(struct percpu_counter *fbc); static inline void percpu_counter_add(struct percpu_counter *fbc, s64 amount) { @@ -44,19 +44,13 @@ static inline void percpu_counter_add(st static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc) { - s64 ret = __percpu_counter_sum(fbc, 0); + s64 ret = __percpu_counter_sum(fbc); return ret < 0 ? 0 : ret; } -static inline s64 percpu_counter_sum_and_set(struct percpu_counter *fbc) -{ - return __percpu_counter_sum(fbc, 1); -} - - static inline s64 percpu_counter_sum(struct percpu_counter *fbc) { - return __percpu_counter_sum(fbc, 0); + return __percpu_counter_sum(fbc); } static inline s64 percpu_counter_read(struct percpu_counter *fbc) diff -urNp linux-2.6.27.orig/lib/percpu_counter.c linux-2.6.27/lib/percpu_counter.c --- linux-2.6.27.orig/lib/percpu_counter.c 2010-02-26 14:10:42.176252671 -0600 +++ linux-2.6.27/lib/percpu_counter.c 2010-02-26 14:18:30.811252658 -0600 @@ -52,7 +52,7 @@ EXPORT_SYMBOL(__percpu_counter_add); * Add up all the per-cpu counts, return the result. This is a more accurate * but much slower version of percpu_counter_read_positive() */ -s64 __percpu_counter_sum(struct percpu_counter *fbc, int set) +s64 __percpu_counter_sum(struct percpu_counter *fbc) { s64 ret; int cpu; @@ -62,11 +62,9 @@ s64 __percpu_counter_sum(struct percpu_c for_each_online_cpu(cpu) { s32 *pcount = per_cpu_ptr(fbc->counters, cpu); ret += *pcount; - if (set) - *pcount = 0; + *pcount = 0; } - if (set) - fbc->count = ret; + fbc->count = ret; spin_unlock(&fbc->lock); return ret; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |