Commit b40607fc authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds

[PATCH] __get_page_state() cpumask cleanup and fix

__get_page_state() has an open-coded for_each_cpu_mask() loop in it.

Tidy that up, then notice that the code was buggy:

	while (cpu < NR_CPUS) {
		unsigned long *in, *out, off;

		if (!cpu_isset(cpu, *cpumask))
			continue;

an obvious infinite loop.  I guess we just never call it with a holey cpu
mask.

Even after my cpumask size-reduction work, this patch increases code size :(

Cc: Paul Jackson <pj@sgi.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 68ed0040
......@@ -1214,24 +1214,22 @@ DEFINE_PER_CPU(long, nr_pagecache_local) = 0;
static void __get_page_state(struct page_state *ret, int nr, cpumask_t *cpumask)
{
int cpu = 0;
unsigned cpu;
memset(ret, 0, nr * sizeof(unsigned long));
cpus_and(*cpumask, *cpumask, cpu_online_map);
cpu = first_cpu(*cpumask);
while (cpu < NR_CPUS) {
unsigned long *in, *out, off;
if (!cpu_isset(cpu, *cpumask))
continue;
for_each_cpu_mask(cpu, *cpumask) {
unsigned long *in;
unsigned long *out;
unsigned off;
unsigned next_cpu;
in = (unsigned long *)&per_cpu(page_states, cpu);
cpu = next_cpu(cpu, *cpumask);
if (likely(cpu < NR_CPUS))
prefetch(&per_cpu(page_states, cpu));
next_cpu = next_cpu(cpu, *cpumask);
if (likely(next_cpu < NR_CPUS))
prefetch(&per_cpu(page_states, next_cpu));
out = (unsigned long *)ret;
for (off = 0; off < nr; off++)
......
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