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IB/ipath: Convert old cpumask api into new one

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Adapt to new api.  We plan to remove old one later.  Almost all
changes are trivial, but there is one real fix: the following code is
unsafe:

	int ncpus = num_online_cpus()
	for (i = 0; i < ncpus; i++) {
		..
	}

because 1) we don't guarantee last bit of online cpus is equal to
num_online_cpus(). some arch assign sparse cpu number.  2) cpu
hotplugging may change cpu_online_mask at same time.  we need to pin
it by get_online_cpus().

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
This commit is contained in:
Motohiro KOSAKI 2011-05-19 01:04:42 +00:00 committed by Roland Dreier
parent 620917de59
commit 5763181172
1 changed files with 7 additions and 4 deletions
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11
drivers/infiniband/hw/ipath/ipath_file_ops.c
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@ -40,6 +40,7 @@
#include <linux/highmem.h>
#include <linux/io.h>
#include <linux/jiffies.h>
#include <linux/cpu.h>
#include <asm/pgtable.h>
#include "ipath_kernel.h"
@ -1684,17 +1685,19 @@ static int find_best_unit(struct file *fp,
* information. There may be some issues with dual core numbering
* as well. This needs more work prior to release.
*/
if (!cpumask_empty(&current->cpus_allowed) &&
!cpumask_full(&current->cpus_allowed)) {
if (!cpumask_empty(tsk_cpus_allowed(current)) &&
!cpumask_full(tsk_cpus_allowed(current))) {
int ncpus = num_online_cpus(), curcpu = -1, nset = 0;
for (i = 0; i < ncpus; i++)
if (cpumask_test_cpu(i, &current->cpus_allowed)) {
get_online_cpus();
for_each_online_cpu(i)
if (cpumask_test_cpu(i, tsk_cpus_allowed(current))) {
ipath_cdbg(PROC, "%s[%u] affinity set for "
"cpu %d/%d\n", current->comm,
current->pid, i, ncpus);
curcpu = i;
nset++;
}
put_online_cpus();
if (curcpu != -1 && nset != ncpus) {
if (npresent) {
prefunit = curcpu / (ncpus / npresent);