Commit a1205868 authored by Alan Stern's avatar Alan Stern Committed by Linus Torvalds
Browse files

[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: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent b30973f8

arch/i386/kernel/acpi/cstate.c

+2 −4
Original line number Diff line number Diff line
@@ -156,11 +156,9 @@ 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;

}

}



arch_initcall(ffh_cstate_init);

__exitcall(ffh_cstate_exit);

block/blktrace.c

+1 −2
Original line number Diff line number Diff line
@@ -394,7 +394,6 @@ 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);

		if (bt->rchan)

			relay_close(bt->rchan);

mm/allocpercpu.c

+5 −4
Original line number Diff line number Diff line
@@ -17,11 +17,10 @@ 
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;

}

}

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));

}

net/ipv6/af_inet6.c

+2 −4
Original line number Diff line number Diff line
@@ -720,9 +720,7 @@ snmp6_mib_free(void *ptr[2]) 
{

	if (ptr == NULL)

		return;

	if (ptr[0])

	free_percpu(ptr[0]);

	if (ptr[1])

	free_percpu(ptr[1]);

	ptr[0] = ptr[1] = NULL;

}