diff options
| author | Gautham R. Shenoy <ego@linux.vnet.ibm.com> | 2014-03-11 02:04:03 +0530 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2014-03-20 13:43:40 +0100 |
| commit | a19423b98704aa85e84097be6d1d44a8615c2340 (patch) | |
| tree | 9e0030a7414998cd016d919cf4f9cc395785cb9a /kernel/cpu.c | |
| parent | dcb99fd9b08cfe1afe426af4d8d3cbc429190f15 (diff) | |
CPU hotplug: Add lockdep annotations to get/put_online_cpus()
Add lockdep annotations for get/put_online_cpus() and
cpu_hotplug_begin()/cpu_hotplug_end().
Cc: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index deff2e69376..33caf5e9770 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -19,6 +19,7 @@ #include <linux/mutex.h> #include <linux/gfp.h> #include <linux/suspend.h> +#include <linux/lockdep.h> #include "smpboot.h" @@ -57,17 +58,30 @@ static struct { * an ongoing cpu hotplug operation. */ int refcount; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif } cpu_hotplug = { .active_writer = NULL, .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock), .refcount = 0, +#ifdef CONFIG_DEBUG_LOCK_ALLOC + .dep_map = {.name = "cpu_hotplug.lock" }, +#endif }; +/* Lockdep annotations for get/put_online_cpus() and cpu_hotplug_begin/end() */ +#define cpuhp_lock_acquire_read() lock_map_acquire_read(&cpu_hotplug.dep_map) +#define cpuhp_lock_acquire() lock_map_acquire(&cpu_hotplug.dep_map) +#define cpuhp_lock_release() lock_map_release(&cpu_hotplug.dep_map) + void get_online_cpus(void) { might_sleep(); if (cpu_hotplug.active_writer == current) return; + cpuhp_lock_acquire_read(); mutex_lock(&cpu_hotplug.lock); cpu_hotplug.refcount++; mutex_unlock(&cpu_hotplug.lock); @@ -87,6 +101,7 @@ void put_online_cpus(void) if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer)) wake_up_process(cpu_hotplug.active_writer); mutex_unlock(&cpu_hotplug.lock); + cpuhp_lock_release(); } EXPORT_SYMBOL_GPL(put_online_cpus); @@ -117,6 +132,7 @@ void cpu_hotplug_begin(void) { cpu_hotplug.active_writer = current; + cpuhp_lock_acquire(); for (;;) { mutex_lock(&cpu_hotplug.lock); if (likely(!cpu_hotplug.refcount)) @@ -131,6 +147,7 @@ void cpu_hotplug_done(void) { cpu_hotplug.active_writer = NULL; mutex_unlock(&cpu_hotplug.lock); + cpuhp_lock_release(); } /* |