From 44fc0e5eec00db5fba748803c95920098089c4cc Mon Sep 17 00:00:00 2001 From: Johan Hedberg Date: Fri, 30 Jan 2015 13:14:36 +0200 Subject: sched/wait: Introduce wait_on_bit_timeout() Add a new wait_on_bit_timeout() helper, basically the same as wait_on_bit() except that it also takes a 'timeout' parameter. All the building blocks like bit_wait_timeout() and out_of_line_wait_on_bit_timeout() are already in place so the addition is rather simple. Signed-off-by: Johan Hedberg Signed-off-by: Peter Zijlstra (Intel) Cc: davem@davemloft.net Cc: Linus Torvalds Link: http://lkml.kernel.org/r/1422616476-2917-2-git-send-email-johan.hedberg@gmail.com Signed-off-by: Ingo Molnar --- include/linux/wait.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 37423e0e1379..537d58eea8a0 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -989,6 +989,32 @@ wait_on_bit_io(void *word, int bit, unsigned mode) mode); } +/** + * wait_on_bit_timeout - wait for a bit to be cleared or a timeout elapses + * @word: the word being waited on, a kernel virtual address + * @bit: the bit of the word being waited on + * @mode: the task state to sleep in + * @timeout: timeout, in jiffies + * + * Use the standard hashed waitqueue table to wait for a bit + * to be cleared. This is similar to wait_on_bit(), except also takes a + * timeout parameter. + * + * Returned value will be zero if the bit was cleared before the + * @timeout elapsed, or non-zero if the @timeout elapsed or process + * received a signal and the mode permitted wakeup on that signal. + */ +static inline int +wait_on_bit_timeout(void *word, int bit, unsigned mode, unsigned long timeout) +{ + might_sleep(); + if (!test_bit(bit, word)) + return 0; + return out_of_line_wait_on_bit_timeout(word, bit, + bit_wait_timeout, + mode, timeout); +} + /** * wait_on_bit_action - wait for a bit to be cleared * @word: the word being waited on, a kernel virtual address -- cgit v1.2.3 From 2c561246524c3319473bf47b558354f7ff47f0cf Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 3 Feb 2015 12:55:31 +0100 Subject: block: Simplify bsg complete all It took me a few tries to figure out what this code did; lets rewrite it into a more regular form. The thing that makes this one 'special' is the BSG_F_BLOCK flag, if that is not set we're not supposed/allowed to block and should spin wait for completion. The (new) io_wait_event() will never see a false condition in case of the spinning and we will therefore not block. Cc: Linus Torvalds Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Jens Axboe --- include/linux/wait.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/linux/wait.h') diff --git a/include/linux/wait.h b/include/linux/wait.h index 2232ed16635a..71fc1d31e48d 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -267,6 +267,21 @@ do { \ __wait_event(wq, condition); \ } while (0) +#define __io_wait_event(wq, condition) \ + (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ + io_schedule()) + +/* + * io_wait_event() -- like wait_event() but with io_schedule() + */ +#define io_wait_event(wq, condition) \ +do { \ + might_sleep(); \ + if (condition) \ + break; \ + __io_wait_event(wq, condition); \ +} while (0) + #define __wait_event_freezable(wq, condition) \ ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ schedule(); try_to_freeze()) -- cgit v1.2.3