[PATCH] for_each_possible_cpu: xfs (6f0419e0) · Commits · 戴 / test

for_each_cpu() actually iterates across all possible CPUs. We've had mistakes in the past where people were using for_each_cpu() where they should have been iterating across only online or present CPUs. This is inefficient and possibly buggy. We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the future. This patch replaces for_each_cpu with for_each_possible_cpu. in xfs. Signed-off-by:

KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by:

Nathan Scott <nathans@sgi.com> Signed-off-by:

Andrew Morton <akpm@osdl.org> Signed-off-by:

Linus Torvalds <torvalds@osdl.org>

fs/xfs/linux-2.6/xfs_stats.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -62,7 +62,7 @@ xfs_read_xfsstats(
		while (j < xstats[i].endpoint) {
		val = 0;
		/* sum over all cpus */
		for_each_cpu(c)
		for_each_possible_cpu(c)
		val += (((__u32)&per_cpu(xfsstats, c) + j));
		len += sprintf(buffer + len, " %u", val);
		j++;
		@@ -70,7 +70,7 @@ xfs_read_xfsstats(
		buffer[len++] = '\n';
		}
		/* extra precision counters */
		for_each_cpu(i) {
		for_each_possible_cpu(i) {
		xs_xstrat_bytes += per_cpu(xfsstats, i).xs_xstrat_bytes;
		xs_write_bytes += per_cpu(xfsstats, i).xs_write_bytes;
		xs_read_bytes += per_cpu(xfsstats, i).xs_read_bytes;

fs/xfs/linux-2.6/xfs_sysctl.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -38,7 +38,7 @@ xfs_stats_clear_proc_handler(

		if (!ret && write && *valp) {
		printk("XFS Clearing xfsstats\n");
		for_each_cpu(c) {
		for_each_possible_cpu(c) {
		preempt_disable();
		/* save vn_active, it's a universal truth! */
		vn_active = per_cpu(xfsstats, c).vn_active;

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