From 2f2a2b60adf368bacd6acd2116c01e32caf936c4 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:18 +0200 Subject: sched/wait: Make the signal_pending() checks consistent There's two patterns to check signals in the __wait_event*() macros: if (!signal_pending(current)) { schedule(); continue; } ret = -ERESTARTSYS; break; And the more natural: if (signal_pending(current)) { ret = -ERESTARTSYS; break; } schedule(); Change them all into the latter form. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092527.956416254@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 35 ++++++++++++++++------------------- 1 file changed, 16 insertions(+), 19 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index a67fc1635592..ccf0c529fd37 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -261,12 +261,11 @@ do { \ prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ if (condition) \ break; \ - if (!signal_pending(current)) { \ - schedule(); \ - continue; \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + break; \ } \ - ret = -ERESTARTSYS; \ - break; \ + schedule(); \ } \ finish_wait(&wq, &__wait); \ } while (0) @@ -302,14 +301,13 @@ do { \ prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ if (condition) \ break; \ - if (!signal_pending(current)) { \ - ret = schedule_timeout(ret); \ - if (!ret) \ - break; \ - continue; \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + break; \ } \ - ret = -ERESTARTSYS; \ - break; \ + ret = schedule_timeout(ret); \ + if (!ret) \ + break; \ } \ if (!ret && (condition)) \ ret = 1; \ @@ -439,14 +437,13 @@ do { \ finish_wait(&wq, &__wait); \ break; \ } \ - if (!signal_pending(current)) { \ - schedule(); \ - continue; \ - } \ - ret = -ERESTARTSYS; \ - abort_exclusive_wait(&wq, &__wait, \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + abort_exclusive_wait(&wq, &__wait, \ TASK_INTERRUPTIBLE, NULL); \ - break; \ + break; \ + } \ + schedule(); \ } \ } while (0) -- cgit v1.2.3 From 2953ef246b058989657e1e77b36b67566ac06f7b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:19 +0200 Subject: sched/wait: Change timeout logic Commit 4c663cf ("wait: fix false timeouts when using wait_event_timeout()") introduced an additional condition check after a timeout but there's a few issues; - it forgot one site - it put the check after the main loop; not at the actual timeout check. Cure both; by wrapping the condition (as suggested by Oleg), this avoids double evaluation of 'condition' which could be quite big. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.028892896@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index ccf0c529fd37..b2afd665e4ea 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -179,6 +179,14 @@ wait_queue_head_t *bit_waitqueue(void *, int); #define wake_up_interruptible_sync_poll(x, m) \ __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) +#define ___wait_cond_timeout(condition, ret) \ +({ \ + bool __cond = (condition); \ + if (__cond && !ret) \ + ret = 1; \ + __cond || !ret; \ +}) + #define __wait_event(wq, condition) \ do { \ DEFINE_WAIT(__wait); \ @@ -217,14 +225,10 @@ do { \ \ for (;;) { \ prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ - if (condition) \ + if (___wait_cond_timeout(condition, ret)) \ break; \ ret = schedule_timeout(ret); \ - if (!ret) \ - break; \ } \ - if (!ret && (condition)) \ - ret = 1; \ finish_wait(&wq, &__wait); \ } while (0) @@ -299,18 +303,14 @@ do { \ \ for (;;) { \ prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ + if (___wait_cond_timeout(condition, ret)) \ break; \ if (signal_pending(current)) { \ ret = -ERESTARTSYS; \ break; \ } \ ret = schedule_timeout(ret); \ - if (!ret) \ - break; \ } \ - if (!ret && (condition)) \ - ret = 1; \ finish_wait(&wq, &__wait); \ } while (0) @@ -815,7 +815,7 @@ do { \ \ for (;;) { \ prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ + if (___wait_cond_timeout(condition, ret)) \ break; \ if (signal_pending(current)) { \ ret = -ERESTARTSYS; \ @@ -824,8 +824,6 @@ do { \ spin_unlock_irq(&lock); \ ret = schedule_timeout(ret); \ spin_lock_irq(&lock); \ - if (!ret) \ - break; \ } \ finish_wait(&wq, &__wait); \ } while (0) -- cgit v1.2.3 From bb632bc44970f75b66df102e831a4fc0692e9159 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:20 +0200 Subject: sched/wait: Change the wait_exclusive control flow Purely a preparatory patch; it changes the control flow to match what will soon be generated by generic code so that that patch can be a unity transform. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.107994763@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index b2afd665e4ea..7d7819dafcc5 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -428,23 +428,24 @@ do { \ #define __wait_event_interruptible_exclusive(wq, condition, ret) \ do { \ + __label__ __out; \ DEFINE_WAIT(__wait); \ \ for (;;) { \ prepare_to_wait_exclusive(&wq, &__wait, \ TASK_INTERRUPTIBLE); \ - if (condition) { \ - finish_wait(&wq, &__wait); \ + if (condition) \ break; \ - } \ if (signal_pending(current)) { \ ret = -ERESTARTSYS; \ abort_exclusive_wait(&wq, &__wait, \ TASK_INTERRUPTIBLE, NULL); \ - break; \ + goto __out; \ } \ schedule(); \ } \ + finish_wait(&wq, &__wait); \ +__out: ; \ } while (0) #define wait_event_interruptible_exclusive(wq, condition) \ -- cgit v1.2.3 From 41a1431b178c3b731d6dfc40b987528b333dd93e Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:21 +0200 Subject: sched/wait: Introduce ___wait_event() There's far too much duplication in the __wait_event macros; in order to fix this introduce ___wait_event() a macro with the capability to replace most other macros. With the previous patches changing the various __wait_event*() implementations to be more uniform; we can now collapse the lot without also changing generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.181897111@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 7d7819dafcc5..29d0249e03ab 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -187,6 +187,42 @@ wait_queue_head_t *bit_waitqueue(void *, int); __cond || !ret; \ }) +#define ___wait_signal_pending(state) \ + ((state == TASK_INTERRUPTIBLE && signal_pending(current)) || \ + (state == TASK_KILLABLE && fatal_signal_pending(current))) + +#define ___wait_nop_ret int ret __always_unused + +#define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ +do { \ + __label__ __out; \ + DEFINE_WAIT(__wait); \ + \ + for (;;) { \ + if (exclusive) \ + prepare_to_wait_exclusive(&wq, &__wait, state); \ + else \ + prepare_to_wait(&wq, &__wait, state); \ + \ + if (condition) \ + break; \ + \ + if (___wait_signal_pending(state)) { \ + ret = -ERESTARTSYS; \ + if (exclusive) { \ + abort_exclusive_wait(&wq, &__wait, \ + state, NULL); \ + goto __out; \ + } \ + break; \ + } \ + \ + cmd; \ + } \ + finish_wait(&wq, &__wait); \ +__out: ; \ +} while (0) + #define __wait_event(wq, condition) \ do { \ DEFINE_WAIT(__wait); \ -- cgit v1.2.3 From 854267f4384243b19c03a2942e84f06f2beb0952 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:22 +0200 Subject: sched/wait: Collapse __wait_event() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.254863348@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 29d0249e03ab..68e3a628e157 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -224,17 +224,8 @@ __out: ; \ } while (0) #define __wait_event(wq, condition) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ - if (condition) \ - break; \ - schedule(); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + ___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, \ + ___wait_nop_ret, schedule()) /** * wait_event - sleep until a condition gets true -- cgit v1.2.3 From ddc1994b8217527e1818f690f17597fc9cedf81b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:23 +0200 Subject: sched/wait: Collapse __wait_event_timeout() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.325264677@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 68e3a628e157..546b94efc82e 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -247,17 +247,9 @@ do { \ } while (0) #define __wait_event_timeout(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ - if (___wait_cond_timeout(condition, ret)) \ - break; \ - ret = schedule_timeout(ret); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + ___wait_event(wq, ___wait_cond_timeout(condition, ret), \ + TASK_UNINTERRUPTIBLE, 0, ret, \ + ret = schedule_timeout(ret)) /** * wait_event_timeout - sleep until a condition gets true or a timeout elapses -- cgit v1.2.3 From f13f4c41c9cf9cd61c896e46e4e7ba2687e2af9c Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:24 +0200 Subject: sched/wait: Collapse __wait_event_interruptible() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.396949919@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 17 ++--------------- 1 file changed, 2 insertions(+), 15 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 546b94efc82e..39e4bbd2c735 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -277,21 +277,8 @@ do { \ }) #define __wait_event_interruptible(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - break; \ - } \ - schedule(); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, ret, \ + schedule()) /** * wait_event_interruptible - sleep until a condition gets true -- cgit v1.2.3 From c2ebb1fb4eddf3d1d66fe31d1e89e83ee211b81c Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:25 +0200 Subject: sched/wait: Collapse __wait_event_interruptible_timeout() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.469616907@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 18 +++--------------- 1 file changed, 3 insertions(+), 15 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 39e4bbd2c735..a79fb15c1dd4 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -304,21 +304,9 @@ do { \ }) #define __wait_event_interruptible_timeout(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (___wait_cond_timeout(condition, ret)) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - break; \ - } \ - ret = schedule_timeout(ret); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + ___wait_event(wq, ___wait_cond_timeout(condition, ret), \ + TASK_INTERRUPTIBLE, 0, ret, \ + ret = schedule_timeout(ret)) /** * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses -- cgit v1.2.3 From 48c2521717b39cb6904941ec2847d9775669207a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:26 +0200 Subject: sched/wait: Collapse __wait_event_interruptible_exclusive() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.541716442@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 22 ++-------------------- 1 file changed, 2 insertions(+), 20 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index a79fb15c1dd4..c4ab172daac0 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -421,26 +421,8 @@ do { \ }) #define __wait_event_interruptible_exclusive(wq, condition, ret) \ -do { \ - __label__ __out; \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait_exclusive(&wq, &__wait, \ - TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - abort_exclusive_wait(&wq, &__wait, \ - TASK_INTERRUPTIBLE, NULL); \ - goto __out; \ - } \ - schedule(); \ - } \ - finish_wait(&wq, &__wait); \ -__out: ; \ -} while (0) + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, ret, \ + schedule()) #define wait_event_interruptible_exclusive(wq, condition) \ ({ \ -- cgit v1.2.3 From 13cb5042a4b80396f77cf5d599d2c002c57b89dc Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:27 +0200 Subject: sched/wait: Collapse __wait_event_lock_irq() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.612813379@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 20 ++++++-------------- 1 file changed, 6 insertions(+), 14 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index c4ab172daac0..d64918e09e3c 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -624,20 +624,12 @@ do { \ #define __wait_event_lock_irq(wq, condition, lock, cmd) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ - if (condition) \ - break; \ - spin_unlock_irq(&lock); \ - cmd; \ - schedule(); \ - spin_lock_irq(&lock); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + ___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, \ + ___wait_nop_ret, \ + spin_unlock_irq(&lock); \ + cmd; \ + schedule(); \ + spin_lock_irq(&lock)) /** * wait_event_lock_irq_cmd - sleep until a condition gets true. The -- cgit v1.2.3 From 8fbd88fa1717601ef91ced49a32f24786b167065 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:28 +0200 Subject: sched/wait: Collapse __wait_event_interruptible_lock_irq() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.686006009@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 26 ++++++-------------------- 1 file changed, 6 insertions(+), 20 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index d64918e09e3c..a577a85004ae 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -689,26 +689,12 @@ do { \ } while (0) -#define __wait_event_interruptible_lock_irq(wq, condition, \ - lock, ret, cmd) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - break; \ - } \ - spin_unlock_irq(&lock); \ - cmd; \ - schedule(); \ - spin_lock_irq(&lock); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_interruptible_lock_irq(wq, condition, lock, ret, cmd) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, ret, \ + spin_unlock_irq(&lock); \ + cmd; \ + schedule(); \ + spin_lock_irq(&lock)) /** * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true. -- cgit v1.2.3 From a1dc6852ac5eecdcd3122ae01703183a3e88e979 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:29 +0200 Subject: sched/wait: Collapse __wait_event_interruptible_lock_irq_timeout() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.759956109@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index a577a85004ae..5d5408b08ba5 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -763,25 +763,12 @@ do { \ __ret; \ }) -#define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ - lock, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (___wait_cond_timeout(condition, ret)) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - break; \ - } \ - spin_unlock_irq(&lock); \ - ret = schedule_timeout(ret); \ - spin_lock_irq(&lock); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_interruptible_lock_irq_timeout(wq, condition, lock, ret) \ + ___wait_event(wq, ___wait_cond_timeout(condition, ret), \ + TASK_INTERRUPTIBLE, 0, ret, \ + spin_unlock_irq(&lock); \ + ret = schedule_timeout(ret); \ + spin_lock_irq(&lock)); /** * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets true or a timeout elapses. -- cgit v1.2.3 From cf7361fd961b6f0510572af6cf8ca3ffba07018b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:31 +0200 Subject: sched/wait: Collapse __wait_event_killable() Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.898691966@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 17 +---------------- 1 file changed, 1 insertion(+), 16 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 5d5408b08ba5..ec3683ee0fc2 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -582,22 +582,7 @@ do { \ #define __wait_event_killable(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \ - if (condition) \ - break; \ - if (!fatal_signal_pending(current)) { \ - schedule(); \ - continue; \ - } \ - ret = -ERESTARTSYS; \ - break; \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + ___wait_event(wq, condition, TASK_KILLABLE, 0, ret, schedule()) /** * wait_event_killable - sleep until a condition gets true -- cgit v1.2.3 From ebdc195f2ec68576876216081035293e37318e86 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:32 +0200 Subject: sched/wait: Collapse __wait_event_hrtimeout() While not a whole-sale replacement like the others we can still reduce the size of __wait_event_hrtimeout() considerably by noting that the actual core of __wait_event_hrtimeout() is identical to what ___wait_event() generates. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092528.972793648@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index ec3683ee0fc2..c065e8af9749 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -337,7 +337,6 @@ do { \ #define __wait_event_hrtimeout(wq, condition, timeout, state) \ ({ \ int __ret = 0; \ - DEFINE_WAIT(__wait); \ struct hrtimer_sleeper __t; \ \ hrtimer_init_on_stack(&__t.timer, CLOCK_MONOTONIC, \ @@ -348,25 +347,15 @@ do { \ current->timer_slack_ns, \ HRTIMER_MODE_REL); \ \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, state); \ - if (condition) \ - break; \ - if (state == TASK_INTERRUPTIBLE && \ - signal_pending(current)) { \ - __ret = -ERESTARTSYS; \ - break; \ - } \ + ___wait_event(wq, condition, state, 0, __ret, \ if (!__t.task) { \ __ret = -ETIME; \ break; \ } \ - schedule(); \ - } \ + schedule()); \ \ hrtimer_cancel(&__t.timer); \ destroy_hrtimer_on_stack(&__t.timer); \ - finish_wait(&wq, &__wait); \ __ret; \ }) -- cgit v1.2.3 From 35a2af94c7ce7130ca292c68b1d27fcfdb648f6b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Oct 2013 11:22:33 +0200 Subject: sched/wait: Make the __wait_event*() interface more friendly Change all __wait_event*() implementations to match the corresponding wait_event*() signature for convenience. In particular this does away with the weird 'ret' logic. Since there are __wait_event*() users this requires we update them too. Reviewed-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131002092529.042563462@infradead.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 113 +++++++++++++++++++++++++-------------------------- 1 file changed, 55 insertions(+), 58 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index c065e8af9749..bd4bd7b479b6 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -179,24 +179,23 @@ wait_queue_head_t *bit_waitqueue(void *, int); #define wake_up_interruptible_sync_poll(x, m) \ __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) -#define ___wait_cond_timeout(condition, ret) \ +#define ___wait_cond_timeout(condition) \ ({ \ bool __cond = (condition); \ - if (__cond && !ret) \ - ret = 1; \ - __cond || !ret; \ + if (__cond && !__ret) \ + __ret = 1; \ + __cond || !__ret; \ }) #define ___wait_signal_pending(state) \ ((state == TASK_INTERRUPTIBLE && signal_pending(current)) || \ (state == TASK_KILLABLE && fatal_signal_pending(current))) -#define ___wait_nop_ret int ret __always_unused - #define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ -do { \ +({ \ __label__ __out; \ DEFINE_WAIT(__wait); \ + long __ret = ret; \ \ for (;;) { \ if (exclusive) \ @@ -208,7 +207,7 @@ do { \ break; \ \ if (___wait_signal_pending(state)) { \ - ret = -ERESTARTSYS; \ + __ret = -ERESTARTSYS; \ if (exclusive) { \ abort_exclusive_wait(&wq, &__wait, \ state, NULL); \ @@ -220,12 +219,12 @@ do { \ cmd; \ } \ finish_wait(&wq, &__wait); \ -__out: ; \ -} while (0) +__out: __ret; \ +}) #define __wait_event(wq, condition) \ - ___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, \ - ___wait_nop_ret, schedule()) + (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ + schedule()) /** * wait_event - sleep until a condition gets true @@ -246,10 +245,10 @@ do { \ __wait_event(wq, condition); \ } while (0) -#define __wait_event_timeout(wq, condition, ret) \ - ___wait_event(wq, ___wait_cond_timeout(condition, ret), \ - TASK_UNINTERRUPTIBLE, 0, ret, \ - ret = schedule_timeout(ret)) +#define __wait_event_timeout(wq, condition, timeout) \ + ___wait_event(wq, ___wait_cond_timeout(condition), \ + TASK_UNINTERRUPTIBLE, 0, timeout, \ + __ret = schedule_timeout(__ret)) /** * wait_event_timeout - sleep until a condition gets true or a timeout elapses @@ -272,12 +271,12 @@ do { \ ({ \ long __ret = timeout; \ if (!(condition)) \ - __wait_event_timeout(wq, condition, __ret); \ + __ret = __wait_event_timeout(wq, condition, timeout); \ __ret; \ }) -#define __wait_event_interruptible(wq, condition, ret) \ - ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, ret, \ +#define __wait_event_interruptible(wq, condition) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ schedule()) /** @@ -299,14 +298,14 @@ do { \ ({ \ int __ret = 0; \ if (!(condition)) \ - __wait_event_interruptible(wq, condition, __ret); \ + __ret = __wait_event_interruptible(wq, condition); \ __ret; \ }) -#define __wait_event_interruptible_timeout(wq, condition, ret) \ - ___wait_event(wq, ___wait_cond_timeout(condition, ret), \ - TASK_INTERRUPTIBLE, 0, ret, \ - ret = schedule_timeout(ret)) +#define __wait_event_interruptible_timeout(wq, condition, timeout) \ + ___wait_event(wq, ___wait_cond_timeout(condition), \ + TASK_INTERRUPTIBLE, 0, timeout, \ + __ret = schedule_timeout(__ret)) /** * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses @@ -330,7 +329,8 @@ do { \ ({ \ long __ret = timeout; \ if (!(condition)) \ - __wait_event_interruptible_timeout(wq, condition, __ret); \ + __ret = __wait_event_interruptible_timeout(wq, \ + condition, timeout); \ __ret; \ }) @@ -347,7 +347,7 @@ do { \ current->timer_slack_ns, \ HRTIMER_MODE_REL); \ \ - ___wait_event(wq, condition, state, 0, __ret, \ + __ret = ___wait_event(wq, condition, state, 0, 0, \ if (!__t.task) { \ __ret = -ETIME; \ break; \ @@ -409,15 +409,15 @@ do { \ __ret; \ }) -#define __wait_event_interruptible_exclusive(wq, condition, ret) \ - ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, ret, \ +#define __wait_event_interruptible_exclusive(wq, condition) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ schedule()) #define wait_event_interruptible_exclusive(wq, condition) \ ({ \ int __ret = 0; \ if (!(condition)) \ - __wait_event_interruptible_exclusive(wq, condition, __ret);\ + __ret = __wait_event_interruptible_exclusive(wq, condition);\ __ret; \ }) @@ -570,8 +570,8 @@ do { \ -#define __wait_event_killable(wq, condition, ret) \ - ___wait_event(wq, condition, TASK_KILLABLE, 0, ret, schedule()) +#define __wait_event_killable(wq, condition) \ + ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule()) /** * wait_event_killable - sleep until a condition gets true @@ -592,18 +592,17 @@ do { \ ({ \ int __ret = 0; \ if (!(condition)) \ - __wait_event_killable(wq, condition, __ret); \ + __ret = __wait_event_killable(wq, condition); \ __ret; \ }) #define __wait_event_lock_irq(wq, condition, lock, cmd) \ - ___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, \ - ___wait_nop_ret, \ - spin_unlock_irq(&lock); \ - cmd; \ - schedule(); \ - spin_lock_irq(&lock)) + (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ + spin_unlock_irq(&lock); \ + cmd; \ + schedule(); \ + spin_lock_irq(&lock)) /** * wait_event_lock_irq_cmd - sleep until a condition gets true. The @@ -663,11 +662,11 @@ do { \ } while (0) -#define __wait_event_interruptible_lock_irq(wq, condition, lock, ret, cmd) \ - ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, ret, \ - spin_unlock_irq(&lock); \ - cmd; \ - schedule(); \ +#define __wait_event_interruptible_lock_irq(wq, condition, lock, cmd) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ + spin_unlock_irq(&lock); \ + cmd; \ + schedule(); \ spin_lock_irq(&lock)) /** @@ -698,10 +697,9 @@ do { \ #define wait_event_interruptible_lock_irq_cmd(wq, condition, lock, cmd) \ ({ \ int __ret = 0; \ - \ if (!(condition)) \ - __wait_event_interruptible_lock_irq(wq, condition, \ - lock, __ret, cmd); \ + __ret = __wait_event_interruptible_lock_irq(wq, \ + condition, lock, cmd); \ __ret; \ }) @@ -730,18 +728,18 @@ do { \ #define wait_event_interruptible_lock_irq(wq, condition, lock) \ ({ \ int __ret = 0; \ - \ if (!(condition)) \ - __wait_event_interruptible_lock_irq(wq, condition, \ - lock, __ret, ); \ + __ret = __wait_event_interruptible_lock_irq(wq, \ + condition, lock,) \ __ret; \ }) -#define __wait_event_interruptible_lock_irq_timeout(wq, condition, lock, ret) \ - ___wait_event(wq, ___wait_cond_timeout(condition, ret), \ - TASK_INTERRUPTIBLE, 0, ret, \ - spin_unlock_irq(&lock); \ - ret = schedule_timeout(ret); \ +#define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ + lock, timeout) \ + ___wait_event(wq, ___wait_cond_timeout(condition), \ + TASK_INTERRUPTIBLE, 0, ret, \ + spin_unlock_irq(&lock); \ + __ret = schedule_timeout(__ret); \ spin_lock_irq(&lock)); /** @@ -771,11 +769,10 @@ do { \ #define wait_event_interruptible_lock_irq_timeout(wq, condition, lock, \ timeout) \ ({ \ - int __ret = timeout; \ - \ + long __ret = timeout; \ if (!(condition)) \ - __wait_event_interruptible_lock_irq_timeout( \ - wq, condition, lock, __ret); \ + __ret = __wait_event_interruptible_lock_irq_timeout( \ + wq, condition, lock, timeout); \ __ret; \ }) -- cgit v1.2.3 From fb869b6e91a3ac235f237f73305ecf34cdc4969b Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 4 Oct 2013 10:24:49 +0200 Subject: sched/wait: Clean up wait.h details a bit Since we are changing wait.h profoundly, use the opportunity to: - add a sentence to explain what this file is about - remove whitespace noise - prettify weird looking line break fixup attempts - standardize type definition and initialization sequences - use consistent style details No code is changed. Acked-by: Peter Zijlstra Cc: Oleg Nesterov Cc: Linus Torvalds Cc: Andrew Morton Link: http://lkml.kernel.org/n/tip-O8dIie5swnctqpupakatvqyq@git.kernel.org Signed-off-by: Ingo Molnar --- include/linux/wait.h | 124 +++++++++++++++++++++++++-------------------------- 1 file changed, 60 insertions(+), 64 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index bd4bd7b479b6..a2726c7dd244 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -1,7 +1,8 @@ #ifndef _LINUX_WAIT_H #define _LINUX_WAIT_H - - +/* + * Linux wait queue related types and methods + */ #include #include #include @@ -13,27 +14,27 @@ typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, v int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *key); struct __wait_queue { - unsigned int flags; + unsigned int flags; #define WQ_FLAG_EXCLUSIVE 0x01 - void *private; - wait_queue_func_t func; - struct list_head task_list; + void *private; + wait_queue_func_t func; + struct list_head task_list; }; struct wait_bit_key { - void *flags; - int bit_nr; -#define WAIT_ATOMIC_T_BIT_NR -1 + void *flags; + int bit_nr; +#define WAIT_ATOMIC_T_BIT_NR -1 }; struct wait_bit_queue { - struct wait_bit_key key; - wait_queue_t wait; + struct wait_bit_key key; + wait_queue_t wait; }; struct __wait_queue_head { - spinlock_t lock; - struct list_head task_list; + spinlock_t lock; + struct list_head task_list; }; typedef struct __wait_queue_head wait_queue_head_t; @@ -84,17 +85,17 @@ extern void __init_waitqueue_head(wait_queue_head_t *q, const char *name, struct static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p) { - q->flags = 0; - q->private = p; - q->func = default_wake_function; + q->flags = 0; + q->private = p; + q->func = default_wake_function; } -static inline void init_waitqueue_func_entry(wait_queue_t *q, - wait_queue_func_t func) +static inline void +init_waitqueue_func_entry(wait_queue_t *q, wait_queue_func_t func) { - q->flags = 0; - q->private = NULL; - q->func = func; + q->flags = 0; + q->private = NULL; + q->func = func; } static inline int waitqueue_active(wait_queue_head_t *q) @@ -114,8 +115,8 @@ static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new) /* * Used for wake-one threads: */ -static inline void __add_wait_queue_exclusive(wait_queue_head_t *q, - wait_queue_t *wait) +static inline void +__add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait) { wait->flags |= WQ_FLAG_EXCLUSIVE; __add_wait_queue(q, wait); @@ -127,23 +128,22 @@ static inline void __add_wait_queue_tail(wait_queue_head_t *head, list_add_tail(&new->task_list, &head->task_list); } -static inline void __add_wait_queue_tail_exclusive(wait_queue_head_t *q, - wait_queue_t *wait) +static inline void +__add_wait_queue_tail_exclusive(wait_queue_head_t *q, wait_queue_t *wait) { wait->flags |= WQ_FLAG_EXCLUSIVE; __add_wait_queue_tail(q, wait); } -static inline void __remove_wait_queue(wait_queue_head_t *head, - wait_queue_t *old) +static inline void +__remove_wait_queue(wait_queue_head_t *head, wait_queue_t *old) { list_del(&old->task_list); } void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key); void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key); -void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr, - void *key); +void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr, void *key); void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr); void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr); void __wake_up_bit(wait_queue_head_t *, void *, int); @@ -170,21 +170,21 @@ wait_queue_head_t *bit_waitqueue(void *, int); /* * Wakeup macros to be used to report events to the targets. */ -#define wake_up_poll(x, m) \ +#define wake_up_poll(x, m) \ __wake_up(x, TASK_NORMAL, 1, (void *) (m)) -#define wake_up_locked_poll(x, m) \ +#define wake_up_locked_poll(x, m) \ __wake_up_locked_key((x), TASK_NORMAL, (void *) (m)) -#define wake_up_interruptible_poll(x, m) \ +#define wake_up_interruptible_poll(x, m) \ __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m)) #define wake_up_interruptible_sync_poll(x, m) \ __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) #define ___wait_cond_timeout(condition) \ ({ \ - bool __cond = (condition); \ - if (__cond && !__ret) \ - __ret = 1; \ - __cond || !__ret; \ + bool __cond = (condition); \ + if (__cond && !__ret) \ + __ret = 1; \ + __cond || !__ret; \ }) #define ___wait_signal_pending(state) \ @@ -209,8 +209,8 @@ wait_queue_head_t *bit_waitqueue(void *, int); if (___wait_signal_pending(state)) { \ __ret = -ERESTARTSYS; \ if (exclusive) { \ - abort_exclusive_wait(&wq, &__wait, \ - state, NULL); \ + abort_exclusive_wait(&wq, &__wait, \ + state, NULL); \ goto __out; \ } \ break; \ @@ -222,7 +222,7 @@ wait_queue_head_t *bit_waitqueue(void *, int); __out: __ret; \ }) -#define __wait_event(wq, condition) \ +#define __wait_event(wq, condition) \ (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ schedule()) @@ -238,9 +238,9 @@ __out: __ret; \ * wake_up() has to be called after changing any variable that could * change the result of the wait condition. */ -#define wait_event(wq, condition) \ +#define wait_event(wq, condition) \ do { \ - if (condition) \ + if (condition) \ break; \ __wait_event(wq, condition); \ } while (0) @@ -270,7 +270,7 @@ do { \ #define wait_event_timeout(wq, condition, timeout) \ ({ \ long __ret = timeout; \ - if (!(condition)) \ + if (!(condition)) \ __ret = __wait_event_timeout(wq, condition, timeout); \ __ret; \ }) @@ -329,7 +329,7 @@ do { \ ({ \ long __ret = timeout; \ if (!(condition)) \ - __ret = __wait_event_interruptible_timeout(wq, \ + __ret = __wait_event_interruptible_timeout(wq, \ condition, timeout); \ __ret; \ }) @@ -569,7 +569,6 @@ do { \ ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1)) - #define __wait_event_killable(wq, condition) \ ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule()) @@ -663,7 +662,7 @@ do { \ #define __wait_event_interruptible_lock_irq(wq, condition, lock, cmd) \ - ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ spin_unlock_irq(&lock); \ cmd; \ schedule(); \ @@ -698,7 +697,7 @@ do { \ ({ \ int __ret = 0; \ if (!(condition)) \ - __ret = __wait_event_interruptible_lock_irq(wq, \ + __ret = __wait_event_interruptible_lock_irq(wq, \ condition, lock, cmd); \ __ret; \ }) @@ -734,18 +733,18 @@ do { \ __ret; \ }) -#define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ - lock, timeout) \ +#define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ + lock, timeout) \ ___wait_event(wq, ___wait_cond_timeout(condition), \ - TASK_INTERRUPTIBLE, 0, ret, \ + TASK_INTERRUPTIBLE, 0, ret, \ spin_unlock_irq(&lock); \ __ret = schedule_timeout(__ret); \ spin_lock_irq(&lock)); /** - * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets true or a timeout elapses. - * The condition is checked under the lock. This is expected - * to be called with the lock taken. + * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets + * true or a timeout elapses. The condition is checked under + * the lock. This is expected to be called with the lock taken. * @wq: the waitqueue to wait on * @condition: a C expression for the event to wait for * @lock: a locked spinlock_t, which will be released before schedule() @@ -783,11 +782,9 @@ do { \ * We plan to remove these interfaces. */ extern void sleep_on(wait_queue_head_t *q); -extern long sleep_on_timeout(wait_queue_head_t *q, - signed long timeout); +extern long sleep_on_timeout(wait_queue_head_t *q, signed long timeout); extern void interruptible_sleep_on(wait_queue_head_t *q); -extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, - signed long timeout); +extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, signed long timeout); /* * Waitqueues which are removed from the waitqueue_head at wakeup time @@ -795,8 +792,7 @@ extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state); void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state); void finish_wait(wait_queue_head_t *q, wait_queue_t *wait); -void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, - unsigned int mode, void *key); +void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, unsigned int mode, void *key); int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); @@ -842,8 +838,8 @@ int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); * One uses wait_on_bit() where one is waiting for the bit to clear, * but has no intention of setting it. */ -static inline int wait_on_bit(void *word, int bit, - int (*action)(void *), unsigned mode) +static inline int +wait_on_bit(void *word, int bit, int (*action)(void *), unsigned mode) { if (!test_bit(bit, word)) return 0; @@ -866,8 +862,8 @@ static inline int wait_on_bit(void *word, int bit, * One uses wait_on_bit_lock() where one is waiting for the bit to * clear with the intention of setting it, and when done, clearing it. */ -static inline int wait_on_bit_lock(void *word, int bit, - int (*action)(void *), unsigned mode) +static inline int +wait_on_bit_lock(void *word, int bit, int (*action)(void *), unsigned mode) { if (!test_and_set_bit(bit, word)) return 0; @@ -891,5 +887,5 @@ int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode) return 0; return out_of_line_wait_on_atomic_t(val, action, mode); } - -#endif + +#endif /* _LINUX_WAIT_H */ -- cgit v1.2.3 From 8922915b38cd8b72f8e5af614b95be71d1d299d4 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Mon, 7 Oct 2013 20:31:06 +0200 Subject: sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too Commit 4c663cfc ("wait: fix false timeouts when using wait_event_timeout()") introduced the additional condition checks after a timeout but only in the "slow" __wait*() paths. wait_event_timeout(wq, CONDITION, 0) still returns 0 if CONDITION is already true and we do not call __wait*(). Now that we have ___wait_cond_timeout() we can use it instead to ensure that __ret will be properly updated. Signed-off-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131007183106.GA10973@redhat.com Signed-off-by: Ingo Molnar --- include/linux/wait.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index a2726c7dd244..04c0260bda8f 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -270,7 +270,7 @@ do { \ #define wait_event_timeout(wq, condition, timeout) \ ({ \ long __ret = timeout; \ - if (!(condition)) \ + if (!___wait_cond_timeout(condition)) \ __ret = __wait_event_timeout(wq, condition, timeout); \ __ret; \ }) @@ -328,7 +328,7 @@ do { \ #define wait_event_interruptible_timeout(wq, condition, timeout) \ ({ \ long __ret = timeout; \ - if (!(condition)) \ + if (!___wait_cond_timeout(condition)) \ __ret = __wait_event_interruptible_timeout(wq, \ condition, timeout); \ __ret; \ @@ -769,7 +769,7 @@ do { \ timeout) \ ({ \ long __ret = timeout; \ - if (!(condition)) \ + if (!___wait_cond_timeout(condition)) \ __ret = __wait_event_interruptible_lock_irq_timeout( \ wq, condition, lock, timeout); \ __ret; \ -- cgit v1.2.3 From c2d816443ef305aba8eaf0bf368f4d3d87494f06 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Mon, 7 Oct 2013 18:18:24 +0200 Subject: sched/wait: Introduce prepare_to_wait_event() Add the new helper, prepare_to_wait_event() which should only be used by ___wait_event(). prepare_to_wait_event() returns -ERESTARTSYS if signal_pending_state() is true, otherwise it does prepare_to_wait/exclusive. This allows to uninline the signal-pending checks in wait_event*() macros. Also, it can initialize wait->private/func. We do not care if they were already initialized, the values are the same. This also shaves a couple of insns from the inlined code. This obviously makes prepare_*() path a little bit slower, but we are likely going to sleep anyway, so I think it makes sense to shrink .text: text data bss dec hex filename =================================================== before: 5126092 2959248 10117120 18202460 115bf5c vmlinux after: 5124618 2955152 10117120 18196890 115a99a vmlinux on my build. Signed-off-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131007161824.GA29757@redhat.com Signed-off-by: Ingo Molnar --- include/linux/wait.h | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 04c0260bda8f..ec099b03e11b 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -187,27 +187,30 @@ wait_queue_head_t *bit_waitqueue(void *, int); __cond || !__ret; \ }) -#define ___wait_signal_pending(state) \ - ((state == TASK_INTERRUPTIBLE && signal_pending(current)) || \ - (state == TASK_KILLABLE && fatal_signal_pending(current))) +#define ___wait_is_interruptible(state) \ + (!__builtin_constant_p(state) || \ + state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \ #define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ ({ \ __label__ __out; \ - DEFINE_WAIT(__wait); \ + wait_queue_t __wait; \ long __ret = ret; \ \ + INIT_LIST_HEAD(&__wait.task_list); \ + if (exclusive) \ + __wait.flags = WQ_FLAG_EXCLUSIVE; \ + else \ + __wait.flags = 0; \ + \ for (;;) { \ - if (exclusive) \ - prepare_to_wait_exclusive(&wq, &__wait, state); \ - else \ - prepare_to_wait(&wq, &__wait, state); \ + long __int = prepare_to_wait_event(&wq, &__wait, state);\ \ if (condition) \ break; \ \ - if (___wait_signal_pending(state)) { \ - __ret = -ERESTARTSYS; \ + if (___wait_is_interruptible(state) && __int) { \ + __ret = __int; \ if (exclusive) { \ abort_exclusive_wait(&wq, &__wait, \ state, NULL); \ @@ -791,6 +794,7 @@ extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, signed long tim */ void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state); void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state); +long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state); void finish_wait(wait_queue_head_t *q, wait_queue_t *wait); void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, unsigned int mode, void *key); int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); -- cgit v1.2.3 From 92ec11809565cf6429c75204e99e0f583b5c9d7c Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Wed, 23 Oct 2013 13:40:55 +0200 Subject: sched/wait: Fix build breakage The wait_event_interruptible_lock_irq() macro is missing a semi-colon which causes a build failure in the i915 DRM driver. Signed-off-by: Thierry Reding Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1382528455-29911-1-git-send-email-treding@nvidia.com Signed-off-by: Ingo Molnar --- include/linux/wait.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index ec099b03e11b..3b23afa04d6b 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -732,7 +732,7 @@ do { \ int __ret = 0; \ if (!(condition)) \ __ret = __wait_event_interruptible_lock_irq(wq, \ - condition, lock,) \ + condition, lock,); \ __ret; \ }) -- cgit v1.2.3 From 7d716456a0ee4e9bd63be9234f886d20382ac950 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 31 Oct 2013 12:48:14 +0100 Subject: sched/wait: Fix __wait_event_interruptible_lock_irq_timeout() __wait_event_interruptible_lock_irq_timeout() needs the timeout parameter passed instead of "ret". This magically compiled since the only user has a local ret variable. Luckily we got a build warning: CC drivers/s390/scsi/zfcp_qdio.o drivers/s390/scsi/zfcp_qdio.c: In function 'zfcp_qdio_sbal_get': include/linux/wait.h:780:15: warning: 'ret' may be used uninitialized Signed-off-by: Heiko Carstens Acked-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20131031114814.GB5551@osiris Signed-off-by: Ingo Molnar --- include/linux/wait.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 3b23afa04d6b..61939ba30aa0 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -739,7 +739,7 @@ do { \ #define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ lock, timeout) \ ___wait_event(wq, ___wait_cond_timeout(condition), \ - TASK_INTERRUPTIBLE, 0, ret, \ + TASK_INTERRUPTIBLE, 0, timeout, \ spin_unlock_irq(&lock); \ __ret = schedule_timeout(__ret); \ spin_lock_irq(&lock)); -- cgit v1.2.3 From 82e06c811163c4d853ed335d56c3378088bc89cc Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Thu, 14 Nov 2013 15:16:16 +1100 Subject: wait: add wait_event_cmd() Add a new API wait_event_cmd(). It's a variant of wait_even() with two commands executed. One is executed before sleep, another after sleep. Modified to match use wait.h approach based on suggestion by Peter Zijlstra - neilb Signed-off-by: Shaohua Li Signed-off-by: NeilBrown --- include/linux/wait.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 61939ba30aa0..eaa00b10abaa 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -278,6 +278,31 @@ do { \ __ret; \ }) +#define __wait_event_cmd(wq, condition, cmd1, cmd2) \ + (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ + cmd1; schedule(); cmd2) + +/** + * wait_event_cmd - sleep until a condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * cmd1: the command will be executed before sleep + * cmd2: the command will be executed after sleep + * + * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + */ +#define wait_event_cmd(wq, condition, cmd1, cmd2) \ +do { \ + if (condition) \ + break; \ + __wait_event_cmd(wq, condition, cmd1, cmd2); \ +} while (0) + #define __wait_event_interruptible(wq, condition) \ ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ schedule()) -- cgit v1.2.3