From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathieu Lacage Subject: [PATCH: asm-generic] atomic_add_unless macro does not handle arguments which use a local variable named c Date: Sun, 27 Jun 2010 12:26:06 +0200 Message-ID: <1277634366.2845.5.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mail4-relais-sop.national.inria.fr ([192.134.164.105]:45881 "EHLO mail4-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754686Ab0F0K0J (ORCPT ); Sun, 27 Jun 2010 06:26:09 -0400 Sender: linux-arch-owner@vger.kernel.org List-ID: To: Arnd Bergmann Cc: linux-arch@vger.kernel.org atomic_add_unless is a macro so, bad things happen if the caller defines a local variable named c, just like like the local variable c defined by the macro. Thus, convert atomic_add_unless to a function. (bug triggered by net/ipv4/netfilter/ipt_CLUSTERIP.c: clusterip_config_find_get calls atomic_inc_not_zero) Signed-off-by: Mathieu Lacage diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h index 058129e..2fadcdb 100644 --- a/include/asm-generic/atomic.h +++ b/include/asm-generic/atomic.h @@ -119,14 +119,23 @@ static inline void atomic_dec(atomic_t *v) #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) -#define atomic_add_unless(v, a, u) \ -({ \ - int c, old; \ - c = atomic_read(v); \ - while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \ - c = old; \ - c != (u); \ -}) +#define atomic_xchg(ptr, v) (xchg(&(ptr)->counter, (v))) +#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new))) + +#define cmpxchg_local(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ + (unsigned long)(n), sizeof(*(ptr)))) + +#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) + +static inline int atomic_add_unless(atomic_t *v, int a, int u) +{ + int c, old; + c = atomic_read(v); + while (c != u && (old = atomic_cmpxchg(v, c, c + a)) != c) + c = old; + return c != u; +} #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) @@ -140,15 +149,6 @@ static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr) local_irq_restore(flags); } -#define atomic_xchg(ptr, v) (xchg(&(ptr)->counter, (v))) -#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new))) - -#define cmpxchg_local(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ - (unsigned long)(n), sizeof(*(ptr)))) - -#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) - /* Assume that atomic operations are already serializing */ #define smp_mb__before_atomic_dec() barrier() #define smp_mb__after_atomic_dec() barrier() -- Mathieu Lacage Tel: +33 4 9238 5056