From f59ca05871a055a73f8e626f2d868f0da248e22c Mon Sep 17 00:00:00 2001 From: Shan Hai Date: Thu, 1 Sep 2011 11:32:03 +0800 Subject: locking, lib/atomic64: Annotate atomic64_lock::lock as raw The spinlock protected atomic64 operations must be irq safe as they are used in hard interrupt context and cannot be preempted on -rt: NIP [c068b218] rt_spin_lock_slowlock+0x78/0x3a8 LR [c068b1e0] rt_spin_lock_slowlock+0x40/0x3a8 Call Trace: [eb459b90] [c068b1e0] rt_spin_lock_slowlock+0x40/0x3a8 (unreliable) [eb459c20] [c068bdb0] rt_spin_lock+0x40/0x98 [eb459c40] [c03d2a14] atomic64_read+0x48/0x84 [eb459c60] [c001aaf4] perf_event_interrupt+0xec/0x28c [eb459d10] [c0010138] performance_monitor_exception+0x7c/0x150 [eb459d30] [c0014170] ret_from_except_full+0x0/0x4c So annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Shan Hai Reviewed-by: Yong Zhang Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- lib/atomic64.c | 44 ++++++++++++++++++++++---------------------- 1 file changed, 22 insertions(+), 22 deletions(-) (limited to 'lib/atomic64.c') diff --git a/lib/atomic64.c b/lib/atomic64.c index e12ae0dd08a8..82b33134e141 100644 --- a/lib/atomic64.c +++ b/lib/atomic64.c @@ -29,7 +29,7 @@ * Ensure each lock is in a separate cacheline. */ static union { - spinlock_t lock; + raw_spinlock_t lock; char pad[L1_CACHE_BYTES]; } atomic64_lock[NR_LOCKS] __cacheline_aligned_in_smp; @@ -48,9 +48,9 @@ long long atomic64_read(const atomic64_t *v) spinlock_t *lock = lock_addr(v); long long val; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); val = v->counter; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return val; } EXPORT_SYMBOL(atomic64_read); @@ -60,9 +60,9 @@ void atomic64_set(atomic64_t *v, long long i) unsigned long flags; spinlock_t *lock = lock_addr(v); - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); v->counter = i; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); } EXPORT_SYMBOL(atomic64_set); @@ -71,9 +71,9 @@ void atomic64_add(long long a, atomic64_t *v) unsigned long flags; spinlock_t *lock = lock_addr(v); - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); v->counter += a; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); } EXPORT_SYMBOL(atomic64_add); @@ -83,9 +83,9 @@ long long atomic64_add_return(long long a, atomic64_t *v) spinlock_t *lock = lock_addr(v); long long val; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); val = v->counter += a; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return val; } EXPORT_SYMBOL(atomic64_add_return); @@ -95,9 +95,9 @@ void atomic64_sub(long long a, atomic64_t *v) unsigned long flags; spinlock_t *lock = lock_addr(v); - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); v->counter -= a; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); } EXPORT_SYMBOL(atomic64_sub); @@ -107,9 +107,9 @@ long long atomic64_sub_return(long long a, atomic64_t *v) spinlock_t *lock = lock_addr(v); long long val; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); val = v->counter -= a; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return val; } EXPORT_SYMBOL(atomic64_sub_return); @@ -120,11 +120,11 @@ long long atomic64_dec_if_positive(atomic64_t *v) spinlock_t *lock = lock_addr(v); long long val; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); val = v->counter - 1; if (val >= 0) v->counter = val; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return val; } EXPORT_SYMBOL(atomic64_dec_if_positive); @@ -135,11 +135,11 @@ long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n) spinlock_t *lock = lock_addr(v); long long val; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); val = v->counter; if (val == o) v->counter = n; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return val; } EXPORT_SYMBOL(atomic64_cmpxchg); @@ -150,10 +150,10 @@ long long atomic64_xchg(atomic64_t *v, long long new) spinlock_t *lock = lock_addr(v); long long val; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); val = v->counter; v->counter = new; - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return val; } EXPORT_SYMBOL(atomic64_xchg); @@ -164,12 +164,12 @@ int atomic64_add_unless(atomic64_t *v, long long a, long long u) spinlock_t *lock = lock_addr(v); int ret = 0; - spin_lock_irqsave(lock, flags); + raw_spin_lock_irqsave(lock, flags); if (v->counter != u) { v->counter += a; ret = 1; } - spin_unlock_irqrestore(lock, flags); + raw_spin_unlock_irqrestore(lock, flags); return ret; } EXPORT_SYMBOL(atomic64_add_unless); @@ -179,7 +179,7 @@ static int init_atomic64_lock(void) int i; for (i = 0; i < NR_LOCKS; ++i) - spin_lock_init(&atomic64_lock[i].lock); + raw_spin_lock_init(&atomic64_lock[i].lock); return 0; } -- cgit v1.2.3 From cb475de3d12df6912bc95048202ae8c280d4cad5 Mon Sep 17 00:00:00 2001 From: Yong Zhang Date: Wed, 14 Sep 2011 15:49:24 +0800 Subject: lib: atomic64: Change the type of local lock to raw_spinlock_t There are still some leftovers of commit f59ca058 [locking, lib/atomic64: Annotate atomic64_lock::lock as raw] [ tglx: Seems I picked the wrong version of that patch :( ] Signed-off-by: Yong Zhang Cc: Peter Zijlstra Cc: Shan Hai Cc: Stephen Rothwell Link: http://lkml.kernel.org/r/20110914074924.GA16096@zhy Signed-off-by: Thomas Gleixner --- lib/atomic64.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'lib/atomic64.c') diff --git a/lib/atomic64.c b/lib/atomic64.c index 82b33134e141..3975470caf4f 100644 --- a/lib/atomic64.c +++ b/lib/atomic64.c @@ -33,7 +33,7 @@ static union { char pad[L1_CACHE_BYTES]; } atomic64_lock[NR_LOCKS] __cacheline_aligned_in_smp; -static inline spinlock_t *lock_addr(const atomic64_t *v) +static inline raw_spinlock_t *lock_addr(const atomic64_t *v) { unsigned long addr = (unsigned long) v; @@ -45,7 +45,7 @@ static inline spinlock_t *lock_addr(const atomic64_t *v) long long atomic64_read(const atomic64_t *v) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); long long val; raw_spin_lock_irqsave(lock, flags); @@ -58,7 +58,7 @@ EXPORT_SYMBOL(atomic64_read); void atomic64_set(atomic64_t *v, long long i) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); raw_spin_lock_irqsave(lock, flags); v->counter = i; @@ -69,7 +69,7 @@ EXPORT_SYMBOL(atomic64_set); void atomic64_add(long long a, atomic64_t *v) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); raw_spin_lock_irqsave(lock, flags); v->counter += a; @@ -80,7 +80,7 @@ EXPORT_SYMBOL(atomic64_add); long long atomic64_add_return(long long a, atomic64_t *v) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); long long val; raw_spin_lock_irqsave(lock, flags); @@ -93,7 +93,7 @@ EXPORT_SYMBOL(atomic64_add_return); void atomic64_sub(long long a, atomic64_t *v) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); raw_spin_lock_irqsave(lock, flags); v->counter -= a; @@ -104,7 +104,7 @@ EXPORT_SYMBOL(atomic64_sub); long long atomic64_sub_return(long long a, atomic64_t *v) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); long long val; raw_spin_lock_irqsave(lock, flags); @@ -117,7 +117,7 @@ EXPORT_SYMBOL(atomic64_sub_return); long long atomic64_dec_if_positive(atomic64_t *v) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); long long val; raw_spin_lock_irqsave(lock, flags); @@ -132,7 +132,7 @@ EXPORT_SYMBOL(atomic64_dec_if_positive); long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); long long val; raw_spin_lock_irqsave(lock, flags); @@ -147,7 +147,7 @@ EXPORT_SYMBOL(atomic64_cmpxchg); long long atomic64_xchg(atomic64_t *v, long long new) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); long long val; raw_spin_lock_irqsave(lock, flags); @@ -161,7 +161,7 @@ EXPORT_SYMBOL(atomic64_xchg); int atomic64_add_unless(atomic64_t *v, long long a, long long u) { unsigned long flags; - spinlock_t *lock = lock_addr(v); + raw_spinlock_t *lock = lock_addr(v); int ret = 0; raw_spin_lock_irqsave(lock, flags); -- cgit v1.2.3