From: David Daney Date: Wed, 11 Sep 2013 21:23:24 +0000 (-0700) Subject: smp: quit unconditionally enabling irq in on_each_cpu_mask and on_each_cpu_cond X-Git-Tag: v5.15~19344^2~147 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=fa688207c9db48b64ab6538abc3fcdf26110b9ec;p=mirror_ubuntu-kernels.git smp: quit unconditionally enabling irq in on_each_cpu_mask and on_each_cpu_cond As in commit f21afc25f9ed ("smp.h: Use local_irq_{save,restore}() in !SMP version of on_each_cpu()"), we don't want to enable irqs if they are not already enabled. There are currently no known problematical callers of these functions, but since it is a known failure pattern, we preemptively fix them. Since they are not trivial functions, make them non-inline by moving them to up.c. This also makes it so we don't have to fix #include dependancies for preempt_{disable,enable}. Signed-off-by: David Daney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/linux/smp.h b/include/linux/smp.h index c8488763277f..3724a9070907 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -29,6 +29,22 @@ extern unsigned int total_cpus; int smp_call_function_single(int cpuid, smp_call_func_t func, void *info, int wait); +/* + * Call a function on processors specified by mask, which might include + * the local one. + */ +void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func, + void *info, bool wait); + +/* + * Call a function on each processor for which the supplied function + * cond_func returns a positive value. This may include the local + * processor. + */ +void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), + smp_call_func_t func, void *info, bool wait, + gfp_t gfp_flags); + #ifdef CONFIG_SMP #include @@ -100,22 +116,6 @@ static inline void call_function_init(void) { } */ int on_each_cpu(smp_call_func_t func, void *info, int wait); -/* - * Call a function on processors specified by mask, which might include - * the local one. - */ -void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func, - void *info, bool wait); - -/* - * Call a function on each processor for which the supplied function - * cond_func returns a positive value. This may include the local - * processor. - */ -void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), - smp_call_func_t func, void *info, bool wait, - gfp_t gfp_flags); - /* * Mark the boot cpu "online" so that it can call console drivers in * printk() and can access its per-cpu storage. @@ -151,36 +151,6 @@ static inline int on_each_cpu(smp_call_func_t func, void *info, int wait) return 0; } -/* - * Note we still need to test the mask even for UP - * because we actually can get an empty mask from - * code that on SMP might call us without the local - * CPU in the mask. - */ -#define on_each_cpu_mask(mask, func, info, wait) \ - do { \ - if (cpumask_test_cpu(0, (mask))) { \ - local_irq_disable(); \ - (func)(info); \ - local_irq_enable(); \ - } \ - } while (0) -/* - * Preemption is disabled here to make sure the cond_func is called under the - * same condtions in UP and SMP. - */ -#define on_each_cpu_cond(cond_func, func, info, wait, gfp_flags)\ - do { \ - void *__info = (info); \ - preempt_disable(); \ - if ((cond_func)(0, __info)) { \ - local_irq_disable(); \ - (func)(__info); \ - local_irq_enable(); \ - } \ - preempt_enable(); \ - } while (0) - static inline void smp_send_reschedule(int cpu) { } #define smp_prepare_boot_cpu() do {} while (0) #define smp_call_function_many(mask, func, info, wait) \ diff --git a/kernel/up.c b/kernel/up.c index c54c75e9faf7..144e57255234 100644 --- a/kernel/up.c +++ b/kernel/up.c @@ -19,3 +19,42 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, return 0; } EXPORT_SYMBOL(smp_call_function_single); + +/* + * Note we still need to test the mask even for UP + * because we actually can get an empty mask from + * code that on SMP might call us without the local + * CPU in the mask. + */ +void on_each_cpu_mask(const struct cpumask *mask, + smp_call_func_t func, void *info, bool wait) +{ + unsigned long flags; + + if (cpumask_test_cpu(0, mask)) { + local_irq_save(flags); + func(info); + local_irq_restore(flags); + } +} +EXPORT_SYMBOL(on_each_cpu_mask); + +/* + * Preemption is disabled here to make sure the cond_func is called under the + * same condtions in UP and SMP. + */ +void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), + smp_call_func_t func, void *info, bool wait, + gfp_t gfp_flags) +{ + unsigned long flags; + + preempt_disable(); + if (cond_func(0, info)) { + local_irq_save(flags); + func(info); + local_irq_restore(flags); + } + preempt_enable(); +} +EXPORT_SYMBOL(on_each_cpu_cond);