From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754493AbZBGHjk (ORCPT ); Sat, 7 Feb 2009 02:39:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753216AbZBGHjc (ORCPT ); Sat, 7 Feb 2009 02:39:32 -0500 Received: from ozlabs.org ([203.10.76.45]:48279 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752299AbZBGHja (ORCPT ); Sat, 7 Feb 2009 02:39:30 -0500 To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Ralf Baechle , "David S. Miller" , Al Viro , Mike Travis CC: "David S. Miller" CC: Ingo Molnar From: Rusty Russell Date: Sat, 7 Feb 2009 18:09:16 +1030 Subject: [PATCH 1/3] cpumask: remove dangerous CPU_MASK_ALL_PTR, &CPU_MASK_ALL. Cc: Al Viro Cc: Mike Travis MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200902071809.17953.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (Thanks to Al Viro for reminding me of this, via Ingo) CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so: #define CPU_MASK_ALL (cpumask_t) { { ... } } Taking the address of such a temporary is questionable at best, unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added CPU_MASK_ALL_PTR: #define CPU_MASK_ALL_PTR (&CPU_MASK_ALL) Which formalizes this practice. One day gcc could bite us over this usage (though we seem to have gotten away with it so far). So replace everywhere which used &CPU_MASK_ALL or CPU_MASK_ALL_PTR with the modern "cpu_all_mask" (a real struct cpumask *), and remove CPU_MASK_ALL_PTR altogether. Also remove the confusing and deprecated large-NR_CPUS-only "cpu_mask_all". Signed-off-by: Rusty Russell Cc: Al Viro Cc: Mike Travis --- arch/mips/alchemy/common/time.c | 2 +- arch/sparc/include/asm/topology_64.h | 2 +- arch/x86/include/asm/es7000/apic.h | 2 +- arch/x86/include/asm/numaq/apic.h | 2 +- include/linux/cpumask.h | 6 ------ init/main.c | 7 +------ kernel/kmod.c | 2 +- kernel/kthread.c | 4 ++-- mm/pdflush.c | 2 +- 9 files changed, 9 insertions(+), 20 deletions(-) diff --git a/arch/mips/alchemy/common/time.c b/arch/mips/alchemy/common/time.c --- a/arch/mips/alchemy/common/time.c +++ b/arch/mips/alchemy/common/time.c @@ -89,7 +89,7 @@ static struct clock_event_device au1x_rt .irq = AU1000_RTC_MATCH2_INT, .set_next_event = au1x_rtcmatch2_set_next_event, .set_mode = au1x_rtcmatch2_set_mode, - .cpumask = CPU_MASK_ALL_PTR, + .cpumask = cpu_all_mask, }; static struct irqaction au1x_rtcmatch2_irqaction = { diff --git a/arch/sparc/include/asm/topology_64.h b/arch/sparc/include/asm/topology_64.h --- a/arch/sparc/include/asm/topology_64.h +++ b/arch/sparc/include/asm/topology_64.h @@ -49,7 +49,7 @@ static inline int pcibus_to_node(struct node_to_cpumask(pcibus_to_node(bus))) #define cpumask_of_pcibus(bus) \ (pcibus_to_node(bus) == -1 ? \ - CPU_MASK_ALL_PTR : \ + cpu_all_mask : \ cpumask_of_node(pcibus_to_node(bus))) #define SD_NODE_INIT (struct sched_domain) { \ diff --git a/arch/x86/include/asm/es7000/apic.h b/arch/x86/include/asm/es7000/apic.h --- a/arch/x86/include/asm/es7000/apic.h +++ b/arch/x86/include/asm/es7000/apic.h @@ -13,7 +13,7 @@ static inline int apic_id_registered(voi static inline const cpumask_t *target_cpus_cluster(void) { - return &CPU_MASK_ALL; + return cpu_all_mask; } static inline const cpumask_t *target_cpus(void) diff --git a/arch/x86/include/asm/numaq/apic.h b/arch/x86/include/asm/numaq/apic.h --- a/arch/x86/include/asm/numaq/apic.h +++ b/arch/x86/include/asm/numaq/apic.h @@ -9,7 +9,7 @@ static inline const cpumask_t *target_cpus(void) { - return &CPU_MASK_ALL; + return cpu_all_mask; } #define NO_BALANCE_IRQ (1) diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -324,8 +324,6 @@ static inline const struct cpumask *get_ [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ } } -#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL) - #else #define CPU_MASK_ALL \ @@ -333,10 +331,6 @@ static inline const struct cpumask *get_ [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ } } - -/* cpu_mask_all is in init/main.c */ -extern cpumask_t cpu_mask_all; -#define CPU_MASK_ALL_PTR (&cpu_mask_all) #endif diff --git a/init/main.c b/init/main.c --- a/init/main.c +++ b/init/main.c @@ -358,11 +358,6 @@ static inline void smp_prepare_cpus(unsi static inline void smp_prepare_cpus(unsigned int maxcpus) { } #else - -#if NR_CPUS > BITS_PER_LONG -cpumask_t cpu_mask_all __read_mostly = CPU_MASK_ALL; -EXPORT_SYMBOL(cpu_mask_all); -#endif /* Setup number of possible processor ids */ int nr_cpu_ids __read_mostly = NR_CPUS; @@ -834,7 +829,7 @@ static int __init kernel_init(void * unu /* * init can run on any cpu. */ - set_cpus_allowed_ptr(current, CPU_MASK_ALL_PTR); + set_cpus_allowed_ptr(current, cpu_all_mask); /* * Tell the world that we're going to be the grim * reaper of innocent orphaned children. diff --git a/kernel/kmod.c b/kernel/kmod.c --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -167,7 +167,7 @@ static int ____call_usermodehelper(void } /* We can run anywhere, unlike our parent keventd(). */ - set_cpus_allowed_ptr(current, CPU_MASK_ALL_PTR); + set_cpus_allowed_ptr(current, cpu_all_mask); /* * Our parent is keventd, which runs with elevated scheduling priority. diff --git a/kernel/kthread.c b/kernel/kthread.c --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -110,7 +110,7 @@ static void create_kthread(struct kthrea */ sched_setscheduler(create->result, SCHED_NORMAL, ¶m); set_user_nice(create->result, KTHREAD_NICE_LEVEL); - set_cpus_allowed_ptr(create->result, CPU_MASK_ALL_PTR); + set_cpus_allowed_ptr(create->result, cpu_all_mask); } complete(&create->done); } @@ -240,7 +240,7 @@ int kthreadd(void *unused) set_task_comm(tsk, "kthreadd"); ignore_signals(tsk); set_user_nice(tsk, KTHREAD_NICE_LEVEL); - set_cpus_allowed_ptr(tsk, CPU_MASK_ALL_PTR); + set_cpus_allowed_ptr(tsk, cpu_all_mask); current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG; diff --git a/mm/pdflush.c b/mm/pdflush.c --- a/mm/pdflush.c +++ b/mm/pdflush.c @@ -191,7 +191,7 @@ static int pdflush(void *dummy) /* * Some configs put our parent kthread in a limited cpuset, - * which kthread() overrides, forcing cpus_allowed == CPU_MASK_ALL. + * which kthread() overrides, forcing cpus_allowed == cpu_all_mask. * Our needs are more modest - cut back to our cpusets cpus_allowed. * This is needed as pdflush's are dynamically created and destroyed. * The boottime pdflush's are easily placed w/o these 2 lines.