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| author | Thomas Gleixner <tglx@linutronix.de> | 2021-08-15 23:29:28 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2021-08-17 19:08:49 +0200 |
| commit | 026659b9774e4c586baeb457557fcfc4e0ad144b (patch) | |
| tree | 5355b9097ba53475d11d1c2de92555d043c9b664 /include/linux/local_lock_internal.h | |
| parent | 31552385f8e9d0869117014bf8e55ba0497e3ec8 (diff) | |
| download | linux-stable-026659b9774e4c586baeb457557fcfc4e0ad144b.tar.gz linux-stable-026659b9774e4c586baeb457557fcfc4e0ad144b.tar.bz2 linux-stable-026659b9774e4c586baeb457557fcfc4e0ad144b.zip | |
locking/local_lock: Add PREEMPT_RT support
On PREEMPT_RT enabled kernels local_lock maps to a per CPU 'sleeping'
spinlock which protects the critical section while staying preemptible. CPU
locality is established by disabling migration.
Provide the necessary types and macros to substitute the non-RT variant.
Co-developed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211306.023630962@linutronix.de
Diffstat (limited to 'include/linux/local_lock_internal.h')
| -rw-r--r-- | include/linux/local_lock_internal.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/include/linux/local_lock_internal.h b/include/linux/local_lock_internal.h index 3f02b818625e..975e33b793a7 100644 --- a/include/linux/local_lock_internal.h +++ b/include/linux/local_lock_internal.h @@ -6,6 +6,8 @@ #include <linux/percpu-defs.h> #include <linux/lockdep.h> +#ifndef CONFIG_PREEMPT_RT + typedef struct { #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; @@ -95,3 +97,45 @@ do { \ local_lock_release(this_cpu_ptr(lock)); \ local_irq_restore(flags); \ } while (0) + +#else /* !CONFIG_PREEMPT_RT */ + +/* + * On PREEMPT_RT local_lock maps to a per CPU spinlock, which protects the + * critical section while staying preemptible. + */ +typedef spinlock_t local_lock_t; + +#define INIT_LOCAL_LOCK(lockname) __LOCAL_SPIN_LOCK_UNLOCKED((lockname)) + +#define __local_lock_init(l) \ + do { \ + local_spin_lock_init((l)); \ + } while (0) + +#define __local_lock(__lock) \ + do { \ + migrate_disable(); \ + spin_lock(this_cpu_ptr((__lock))); \ + } while (0) + +#define __local_lock_irq(lock) __local_lock(lock) + +#define __local_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + __local_lock(lock); \ + } while (0) + +#define __local_unlock(__lock) \ + do { \ + spin_unlock(this_cpu_ptr((__lock))); \ + migrate_enable(); \ + } while (0) + +#define __local_unlock_irq(lock) __local_unlock(lock) + +#define __local_unlock_irqrestore(lock, flags) __local_unlock(lock) + +#endif /* CONFIG_PREEMPT_RT */ |