[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>
diff --git a/arch/i386/kernel/acpi/cstate.c b/arch/i386/kernel/acpi/cstate.c
index 4664b55..12e937c 100644
--- a/arch/i386/kernel/acpi/cstate.c
+++ b/arch/i386/kernel/acpi/cstate.c
@@ -156,10 +156,8 @@
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);
diff --git a/block/blktrace.c b/block/blktrace.c
index 74e02c0..d3679dd 100644
--- a/block/blktrace.c
+++ b/block/blktrace.c
@@ -394,8 +394,7 @@
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);
diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c
index eaa9abe..b2486cf 100644
--- a/mm/allocpercpu.c
+++ b/mm/allocpercpu.c
@@ -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 @@
*/
void percpu_free(void *__pdata)
{
+ if (unlikely(!__pdata))
+ return;
__percpu_depopulate_mask(__pdata, &cpu_possible_map);
kfree(__percpu_disguise(__pdata));
}
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 87c8f54..e5cd83b 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -720,10 +720,8 @@
{
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;
}