From a120586873d3d64de93bd6d593d237e131994e58 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Wed, 6 Dec 2006 20:32:37 -0800 Subject: [PATCH] [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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/acpi/cstate.c | 6 ++---- block/blktrace.c | 3 +-- mm/allocpercpu.c | 9 +++++---- net/ipv6/af_inet6.c | 6 ++---- 4 files changed, 10 insertions(+), 14 deletions(-) diff --git a/arch/i386/kernel/acpi/cstate.c b/arch/i386/kernel/acpi/cstate.c index 4664b55f62..12e937c1ce 100644 --- a/arch/i386/kernel/acpi/cstate.c +++ b/arch/i386/kernel/acpi/cstate.c @@ -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); diff --git a/block/blktrace.c b/block/blktrace.c index 74e02c04b2..d3679dd1d2 100644 --- a/block/blktrace.c +++ b/block/blktrace.c @@ -394,8 +394,7 @@ err: 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 eaa9abeea5..b2486cf887 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 @@ 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)); } diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 87c8f54872..e5cd83b220 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -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; } -- 2.39.5