[PATCH] more for_each_cpu() conversions
When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all. The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().
This patch is a kernel-wide sweep of all instances of NR_CPUS. I found very
few instances of this bug, if any. But the patch converts lots of open-coded
test to use the preferred helper macros.
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/xfs/linux-2.6/xfs_stats.c b/fs/xfs/linux-2.6/xfs_stats.c
index 8955720..713e6a7 100644
--- a/fs/xfs/linux-2.6/xfs_stats.c
+++ b/fs/xfs/linux-2.6/xfs_stats.c
@@ -62,18 +62,15 @@
while (j < xstats[i].endpoint) {
val = 0;
/* sum over all cpus */
- for (c = 0; c < NR_CPUS; c++) {
- if (!cpu_possible(c)) continue;
+ for_each_cpu(c)
val += *(((__u32*)&per_cpu(xfsstats, c) + j));
- }
len += sprintf(buffer + len, " %u", val);
j++;
}
buffer[len++] = '\n';
}
/* extra precision counters */
- for (i = 0; i < NR_CPUS; i++) {
- if (!cpu_possible(i)) continue;
+ for_each_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;