From 28f4197e5d4707311febeec8a0eb97cb5fd93c97 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 1 Jun 2010 12:23:18 +0200 Subject: [PATCH] block: disable preemption before using sched_clock() Commit 9195291e5f05e01d67f9a09c756b8aca8f009089 added calls to sched_clock() from preemptible code. sched_clock() is both the wrong interface AND cannot be called without preempt disabled. Apply a temporary fix to get rid of the warnings, a real patch is in the works. Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 8b7f5e0914ad..09a840264d6f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1211,14 +1211,23 @@ struct work_struct; int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); #ifdef CONFIG_BLK_CGROUP +/* + * This should not be using sched_clock(). A real patch is in progress + * to fix this up, until that is in place we need to disable preemption + * around sched_clock() in this function and set_io_start_time_ns(). + */ static inline void set_start_time_ns(struct request *req) { + preempt_disable(); req->start_time_ns = sched_clock(); + preempt_enable(); } static inline void set_io_start_time_ns(struct request *req) { + preempt_disable(); req->io_start_time_ns = sched_clock(); + preempt_enable(); } static inline uint64_t rq_start_time_ns(struct request *req) -- 2.50.1