Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx> --- kernel/trace/blktrace.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index e3210951f1f0..1ebaffb6a3d2 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -1325,8 +1325,25 @@ static void blk_add_trace_bio_complete(void *ignore, static void blk_add_trace_bio_backmerge(void *ignore, struct bio *bio) { - blk_add_trace_bio(bio->bi_bdev->bd_disk->queue, bio, BLK_TA_BACKMERGE, - 0); + u64 ta = 0; + struct blk_trace *bt; + struct blk_trace_ext *bte; + + rcu_read_lock(); + bt = rcu_dereference(bio->bi_bdev->bd_disk->queue->blk_trace); + bte = rcu_dereference(bio->bi_bdev->bd_disk->queue->blk_trace_ext); + if (likely(!bt) && likely(!bte)) { + rcu_read_unlock(); + return; + } + + if (bt) { + ta = BLK_TA_BACKMERGE; + } else if (bte) { + ta = BLK_TA_BACKMERGE_EXT; + } + rcu_read_unlock(); + blk_add_trace_bio(bio->bi_bdev->bd_disk->queue, bio, ta, 0); } static void blk_add_trace_bio_frontmerge(void *ignore, struct bio *bio) -- 2.22.1