[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/include/asm-alpha/mmu_context.h b/include/asm-alpha/mmu_context.h
index 6f92482..0c017fc 100644
--- a/include/asm-alpha/mmu_context.h
+++ b/include/asm-alpha/mmu_context.h
@@ -231,9 +231,8 @@
{
int i;
- for (i = 0; i < NR_CPUS; i++)
- if (cpu_online(i))
- mm->context[i] = 0;
+ for_each_online_cpu(i)
+ mm->context[i] = 0;
if (tsk != current)
task_thread_info(tsk)->pcb.ptbr
= ((unsigned long)mm->pgd - IDENT_ADDR) >> PAGE_SHIFT;
diff --git a/include/asm-alpha/topology.h b/include/asm-alpha/topology.h
index eb740e2..420ccde 100644
--- a/include/asm-alpha/topology.h
+++ b/include/asm-alpha/topology.h
@@ -27,8 +27,8 @@
cpumask_t node_cpu_mask = CPU_MASK_NONE;
int cpu;
- for(cpu = 0; cpu < NR_CPUS; cpu++) {
- if (cpu_online(cpu) && (cpu_to_node(cpu) == node))
+ for_each_online_cpu(cpu) {
+ if (cpu_to_node(cpu) == node)
cpu_set(cpu, node_cpu_mask);
}
diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index 9044aeb..78cf455 100644
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -19,10 +19,9 @@
#define percpu_modcopy(pcpudst, src, size) \
do { \
unsigned int __i; \
- for (__i = 0; __i < NR_CPUS; __i++) \
- if (cpu_possible(__i)) \
- memcpy((pcpudst)+__per_cpu_offset[__i], \
- (src), (size)); \
+ for_each_cpu(__i) \
+ memcpy((pcpudst)+__per_cpu_offset[__i], \
+ (src), (size)); \
} while (0)
#else /* ! SMP */
diff --git a/include/asm-powerpc/percpu.h b/include/asm-powerpc/percpu.h
index e31922c..464301c 100644
--- a/include/asm-powerpc/percpu.h
+++ b/include/asm-powerpc/percpu.h
@@ -27,10 +27,9 @@
#define percpu_modcopy(pcpudst, src, size) \
do { \
unsigned int __i; \
- for (__i = 0; __i < NR_CPUS; __i++) \
- if (cpu_possible(__i)) \
- memcpy((pcpudst)+__per_cpu_offset(__i), \
- (src), (size)); \
+ for_each_cpu(__i) \
+ memcpy((pcpudst)+__per_cpu_offset(__i), \
+ (src), (size)); \
} while (0)
extern void setup_per_cpu_areas(void);
diff --git a/include/asm-s390/percpu.h b/include/asm-s390/percpu.h
index 123fcac..e10ed87 100644
--- a/include/asm-s390/percpu.h
+++ b/include/asm-s390/percpu.h
@@ -46,10 +46,9 @@
#define percpu_modcopy(pcpudst, src, size) \
do { \
unsigned int __i; \
- for (__i = 0; __i < NR_CPUS; __i++) \
- if (cpu_possible(__i)) \
- memcpy((pcpudst)+__per_cpu_offset[__i], \
- (src), (size)); \
+ for_each_cpu(__i) \
+ memcpy((pcpudst)+__per_cpu_offset[__i], \
+ (src), (size)); \
} while (0)
#else /* ! SMP */
diff --git a/include/asm-sparc64/percpu.h b/include/asm-sparc64/percpu.h
index aea4e51..82032e1 100644
--- a/include/asm-sparc64/percpu.h
+++ b/include/asm-sparc64/percpu.h
@@ -26,10 +26,9 @@
#define percpu_modcopy(pcpudst, src, size) \
do { \
unsigned int __i; \
- for (__i = 0; __i < NR_CPUS; __i++) \
- if (cpu_possible(__i)) \
- memcpy((pcpudst)+__per_cpu_offset(__i), \
- (src), (size)); \
+ for_each_cpu(__i) \
+ memcpy((pcpudst)+__per_cpu_offset(__i), \
+ (src), (size)); \
} while (0)
#else /* ! SMP */
diff --git a/include/asm-x86_64/percpu.h b/include/asm-x86_64/percpu.h
index 29a6b04..4405b4a 100644
--- a/include/asm-x86_64/percpu.h
+++ b/include/asm-x86_64/percpu.h
@@ -26,10 +26,9 @@
#define percpu_modcopy(pcpudst, src, size) \
do { \
unsigned int __i; \
- for (__i = 0; __i < NR_CPUS; __i++) \
- if (cpu_possible(__i)) \
- memcpy((pcpudst)+__per_cpu_offset(__i), \
- (src), (size)); \
+ for_each_cpu(__i) \
+ memcpy((pcpudst)+__per_cpu_offset(__i), \
+ (src), (size)); \
} while (0)
extern void setup_per_cpu_areas(void);
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index eef5ccd..fd647fd 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -149,22 +149,16 @@
({ \
typeof(gendiskp->dkstats->field) res = 0; \
int i; \
- for (i=0; i < NR_CPUS; i++) { \
- if (!cpu_possible(i)) \
- continue; \
+ for_each_cpu(i) \
res += per_cpu_ptr(gendiskp->dkstats, i)->field; \
- } \
res; \
})
static inline void disk_stat_set_all(struct gendisk *gendiskp, int value) {
int i;
- for (i=0; i < NR_CPUS; i++) {
- if (cpu_possible(i)) {
- memset(per_cpu_ptr(gendiskp->dkstats, i), value,
- sizeof (struct disk_stats));
- }
- }
+ for_each_cpu(i)
+ memset(per_cpu_ptr(gendiskp->dkstats, i), value,
+ sizeof (struct disk_stats));
}
#else
