diff options
| author | Rusty Russell <rusty@rustcorp.com.au> | 2012-05-08 13:29:45 +0930 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-05-29 23:28:41 -0400 |
| commit | 9dd6fa03ab31bb57cee4623a689d058d222fbe68 (patch) | |
| tree | 3f55c3527ecae7a053b0305d0a8f45e8328a416c /include/linux/lglock.h | |
| parent | ea022dfb3c2a4680483b00eb2fecc9fc4f6091d1 (diff) | |
| download | lwn-9dd6fa03ab31bb57cee4623a689d058d222fbe68.tar.gz lwn-9dd6fa03ab31bb57cee4623a689d058d222fbe68.zip | |
lglock: remove online variants of lock
Optimizing the slow paths adds a lot of complexity. If you need to
grab every lock often, you have other problems.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include/linux/lglock.h')
| -rw-r--r-- | include/linux/lglock.h | 58 |
1 files changed, 2 insertions, 56 deletions
diff --git a/include/linux/lglock.h b/include/linux/lglock.h index 87f402ccec55..0fdd821e77b7 100644 --- a/include/linux/lglock.h +++ b/include/linux/lglock.h @@ -28,8 +28,8 @@ #define br_lock_init(name) name##_lock_init() #define br_read_lock(name) name##_local_lock() #define br_read_unlock(name) name##_local_unlock() -#define br_write_lock(name) name##_global_lock_online() -#define br_write_unlock(name) name##_global_unlock_online() +#define br_write_lock(name) name##_global_lock() +#define br_write_unlock(name) name##_global_unlock() #define DECLARE_BRLOCK(name) DECLARE_LGLOCK(name) #define DEFINE_BRLOCK(name) DEFINE_LGLOCK(name) @@ -42,8 +42,6 @@ #define lg_local_unlock_cpu(name, cpu) name##_local_unlock_cpu(cpu) #define lg_global_lock(name) name##_global_lock() #define lg_global_unlock(name) name##_global_unlock() -#define lg_global_lock_online(name) name##_global_lock_online() -#define lg_global_unlock_online(name) name##_global_unlock_online() #ifdef CONFIG_DEBUG_LOCK_ALLOC #define LOCKDEP_INIT_MAP lockdep_init_map @@ -68,36 +66,13 @@ extern void name##_local_unlock_cpu(int cpu); \ extern void name##_global_lock(void); \ extern void name##_global_unlock(void); \ - extern void name##_global_lock_online(void); \ - extern void name##_global_unlock_online(void); \ #define DEFINE_LGLOCK(name) \ \ DEFINE_SPINLOCK(name##_cpu_lock); \ - cpumask_t name##_cpus __read_mostly; \ DEFINE_PER_CPU(arch_spinlock_t, name##_lock); \ DEFINE_LGLOCK_LOCKDEP(name); \ \ - static int \ - name##_lg_cpu_callback(struct notifier_block *nb, \ - unsigned long action, void *hcpu) \ - { \ - switch (action & ~CPU_TASKS_FROZEN) { \ - case CPU_UP_PREPARE: \ - spin_lock(&name##_cpu_lock); \ - cpu_set((unsigned long)hcpu, name##_cpus); \ - spin_unlock(&name##_cpu_lock); \ - break; \ - case CPU_UP_CANCELED: case CPU_DEAD: \ - spin_lock(&name##_cpu_lock); \ - cpu_clear((unsigned long)hcpu, name##_cpus); \ - spin_unlock(&name##_cpu_lock); \ - } \ - return NOTIFY_OK; \ - } \ - static struct notifier_block name##_lg_cpu_notifier = { \ - .notifier_call = name##_lg_cpu_callback, \ - }; \ void name##_lock_init(void) { \ int i; \ LOCKDEP_INIT_MAP(&name##_lock_dep_map, #name, &name##_lock_key, 0); \ @@ -106,11 +81,6 @@ lock = &per_cpu(name##_lock, i); \ *lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; \ } \ - register_hotcpu_notifier(&name##_lg_cpu_notifier); \ - get_online_cpus(); \ - for_each_online_cpu(i) \ - cpu_set(i, name##_cpus); \ - put_online_cpus(); \ } \ EXPORT_SYMBOL(name##_lock_init); \ \ @@ -150,30 +120,6 @@ } \ EXPORT_SYMBOL(name##_local_unlock_cpu); \ \ - void name##_global_lock_online(void) { \ - int i; \ - spin_lock(&name##_cpu_lock); \ - rwlock_acquire(&name##_lock_dep_map, 0, 0, _RET_IP_); \ - for_each_cpu(i, &name##_cpus) { \ - arch_spinlock_t *lock; \ - lock = &per_cpu(name##_lock, i); \ - arch_spin_lock(lock); \ - } \ - } \ - EXPORT_SYMBOL(name##_global_lock_online); \ - \ - void name##_global_unlock_online(void) { \ - int i; \ - rwlock_release(&name##_lock_dep_map, 1, _RET_IP_); \ - for_each_cpu(i, &name##_cpus) { \ - arch_spinlock_t *lock; \ - lock = &per_cpu(name##_lock, i); \ - arch_spin_unlock(lock); \ - } \ - spin_unlock(&name##_cpu_lock); \ - } \ - EXPORT_SYMBOL(name##_global_unlock_online); \ - \ void name##_global_lock(void) { \ int i; \ preempt_disable(); \ |