From 8eb456be75af7e5a7ac0cd223eaa198cf7ee2ac1 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Tue, 17 Nov 2020 08:58:38 -0800 Subject: [PATCH] scsi: ufs: Fix clkgating on/off The following call stack prevents clk_gating at every I/O completion. We can remove the condition, ufshcd_any_tag_in_use(), since clkgating_work will check it again. ufshcd_complete_requests(struct ufs_hba *hba) ufshcd_transfer_req_compl() __ufshcd_transfer_req_compl() __ufshcd_release(hba) if (ufshcd_any_tag_in_use() == 1) return; ufshcd_tmc_handler(hba); blk_mq_tagset_busy_iter(); Note that this still requires work to deal with a potential race condition when user sets clkgating.delay_ms to very small value. That can cause preventing clkgating by the check of ufshcd_any_tag_in_use() in gate_work. Link: https://lore.kernel.org/r/20201117165839.1643377-7-jaegeuk@kernel.org Fixes: 7252a3603015 ("scsi: ufs: Avoid busy-waiting by eliminating tag conflicts") Reviewed-by: Asutosh Das Reviewed-by: Can Guo Signed-off-by: Jaegeuk Kim Signed-off-by: Martin K. Petersen --- drivers/scsi/ufs/ufshcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 55d795fdaab3..deaaac67e055 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1756,7 +1756,7 @@ static void __ufshcd_release(struct ufs_hba *hba) if (hba->clk_gating.active_reqs || hba->clk_gating.is_suspended || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL || - ufshcd_any_tag_in_use(hba) || hba->outstanding_tasks || + hba->outstanding_tasks || hba->active_uic_cmd || hba->uic_async_done || hba->clk_gating.state == CLKS_OFF) return; -- 2.25.1