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

[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

mm/page_alloc.c

+9 −11
Original line number Diff line number Diff line
@@ -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++)