From 6afe5ff62318fa752a965332d39e0033cd5b0d6e Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Thu, 22 Jan 2015 13:05:19 -0500 Subject: sched: add bit_wait_io for 3.18 ext4 backport Excerpted from commit 743162013: "sched: Remove proliferation of wait_on_bit() action functions" Signed-off-by: Theodore Ts'o --- include/linux/wait.h | 30 +++++++++++++++++++++++++++++- kernel/wait.c | 9 +++++++++ 2 files changed, 38 insertions(+), 1 deletion(-) diff --git a/include/linux/wait.h b/include/linux/wait.h index c8e576022..569d33b6b 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -959,5 +959,33 @@ static inline int wait_on_bit_lock(void *word, int bit, return 0; return out_of_line_wait_on_bit_lock(word, bit, action, mode); } - + +/* 3.18 backport */ +extern int bit_wait_io(void *); + +/** + * wait_on_bit_io - wait for a bit to be cleared + * @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 + * + * Use the standard hashed waitqueue table to wait for a bit + * to be cleared. This is similar to wait_on_bit(), but calls + * io_schedule() instead of schedule() for the actual waiting. + * + * Returned value will be zero if the bit was cleared, or non-zero + * if the process received a signal and the mode permitted wakeup + * on that signal. + */ +static inline int +wait_on_bit_io(void *word, int bit, unsigned mode) +{ + might_sleep(); + if (!test_bit(bit, word)) + return 0; + return out_of_line_wait_on_bit(word, bit, + bit_wait_io, + mode); +} + #endif diff --git a/kernel/wait.c b/kernel/wait.c index 6698e0c04..bca170ef3 100644 --- a/kernel/wait.c +++ b/kernel/wait.c @@ -287,3 +287,12 @@ wait_queue_head_t *bit_waitqueue(void *word, int bit) return &zone->wait_table[hash_long(val, zone->wait_table_bits)]; } EXPORT_SYMBOL(bit_waitqueue); + +__sched int bit_wait_io(void *word) +{ + if (signal_pending_state(current->state, current)) + return 1; + io_schedule(); + return 0; +} +EXPORT_SYMBOL(bit_wait_io); -- cgit v1.2.3