From: Zhang Yi yi.zhang@huawei.com
mainline inclusion from mainline-v5.14-rc1 commit 76a8040817b4b9c69b53f9b326987fa891b4082a category: bugfix bugzilla: 109296 https://gitee.com/openeuler/kernel/issues/I4D2TX CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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After commit a79050434b45 ("blk-rq-qos: refactor out common elements of blk-wbt"), if throttle was disabled by wbt_disable_default(), we could not enable again, fix this by set enable_state back to WBT_STATE_ON_DEFAULT.
Fixes: a79050434b45 ("blk-rq-qos: refactor out common elements of blk-wbt") Signed-off-by: Zhang Yi yi.zhang@huawei.com Link: https://lore.kernel.org/r/20210619093700.920393-3-yi.zhang@huawei.com Signed-off-by: Jens Axboe axboe@kernel.dk Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Chen Jun chenjun102@huawei.com --- block/blk-wbt.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/block/blk-wbt.c b/block/blk-wbt.c index d90082c6b41f..35d81b5deae1 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -637,9 +637,13 @@ void wbt_set_write_cache(struct request_queue *q, bool write_cache_on) void wbt_enable_default(struct request_queue *q) { struct rq_qos *rqos = wbt_rq_qos(q); + /* Throttling already enabled? */ - if (rqos) + if (rqos) { + if (RQWB(rqos)->enable_state == WBT_STATE_OFF_DEFAULT) + RQWB(rqos)->enable_state = WBT_STATE_ON_DEFAULT; return; + }
/* Queue not registered? Maybe shutting down... */ if (!blk_queue_registered(q))