From 2b50f230f76f8ef954f12ac34a648e1978f6adf0 Mon Sep 17 00:00:00 2001
From: Douglas Anderson <dianders@chromium.org>
Date: Wed, 26 Jun 2019 12:59:19 -0700
Subject: [PATCH] block, bfq: Init saved_wr_start_at_switch_to_srt in unlikely
case
Some debug code suggested by Paolo was tripping when I did reboot
stress tests. Specifically in bfq_bfqq_resume_state()
"bic->saved_wr_start_at_switch_to_srt" was later than the current
value of "jiffies". A bit of debugging showed that
"bic->saved_wr_start_at_switch_to_srt" was actually 0 and a bit more
debugging showed that was because we had run through the "unlikely"
case in the bfq_bfqq_save_state() function.
Let's init "saved_wr_start_at_switch_to_srt" in the unlikely case to
something sane.
NOTE: this fixes no known real-world errors.
Reviewed-by: Paolo Valente <paolo.valente@linaro.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
block/bfq-iosched.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 72840ebf953e4..008c93d6b8d79 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -2678,6 +2678,7 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
* to enjoy weight raising if split soon.
*/
bic->saved_wr_coeff = bfqq->bfqd->bfq_wr_coeff;
+ bic->saved_wr_start_at_switch_to_srt = bfq_smallest_from_now();
bic->saved_wr_cur_max_time = bfq_wr_duration(bfqq->bfqd);
bic->saved_last_wr_start_finish = jiffies;
} else {
--
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