[PATCH] Allow NULL pointers in percpu_free

The patch (as824b) makes percpu_free() ignore NULL arguments, as one would
expect for a deallocation routine.  (Note that free_percpu is #defined as
percpu_free in include/linux/percpu.h.) A few callers are updated to remove
now-unneeded tests for NULL.  A few other callers already seem to assume
that passing a NULL pointer to percpu_free() is okay!

The patch also removes an unnecessary NULL check in percpu_depopulate().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Alan Stern 2006-12-06 20:32:37 -08:00 committed by Linus Torvalds
parent b30973f877
commit a120586873
4 changed files with 10 additions and 14 deletions

View File

@ -156,10 +156,8 @@ static int __init ffh_cstate_init(void)
static void __exit ffh_cstate_exit(void)
{
if (cpu_cstate_entry) {
free_percpu(cpu_cstate_entry);
cpu_cstate_entry = NULL;
}
free_percpu(cpu_cstate_entry);
cpu_cstate_entry = NULL;
}
arch_initcall(ffh_cstate_init);

View File

@ -394,8 +394,7 @@ static int blk_trace_setup(request_queue_t *q, struct block_device *bdev,
if (bt) {
if (bt->dropped_file)
debugfs_remove(bt->dropped_file);
if (bt->sequence)
free_percpu(bt->sequence);
free_percpu(bt->sequence);
if (bt->rchan)
relay_close(bt->rchan);
kfree(bt);

View File

@ -17,10 +17,9 @@
void percpu_depopulate(void *__pdata, int cpu)
{
struct percpu_data *pdata = __percpu_disguise(__pdata);
if (pdata->ptrs[cpu]) {
kfree(pdata->ptrs[cpu]);
pdata->ptrs[cpu] = NULL;
}
kfree(pdata->ptrs[cpu]);
pdata->ptrs[cpu] = NULL;
}
EXPORT_SYMBOL_GPL(percpu_depopulate);
@ -123,6 +122,8 @@ EXPORT_SYMBOL_GPL(__percpu_alloc_mask);
*/
void percpu_free(void *__pdata)
{
if (unlikely(!__pdata))
return;
__percpu_depopulate_mask(__pdata, &cpu_possible_map);
kfree(__percpu_disguise(__pdata));
}

View File

@ -720,10 +720,8 @@ snmp6_mib_free(void *ptr[2])
{
if (ptr == NULL)
return;
if (ptr[0])
free_percpu(ptr[0]);
if (ptr[1])
free_percpu(ptr[1]);
free_percpu(ptr[0]);
free_percpu(ptr[1]);
ptr[0] = ptr[1] = NULL;
}