On 2020-10-27 03:51, Jaegeuk Kim wrote:
The below call stack prevents clk_gating at every IO 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 a work to deal with a potential racy
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.
Fixes: 7252a3603015 ("scsi: ufs: Avoid busy-waiting by eliminating tag
conflicts")
Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
Reviewed-by: Asutosh Das <asuto...@codeaurora.org>
Reviewed-by: Can Guo <c...@codeaurora.org>
---
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 b8a54d09e750..86c8dee01ca9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1746,7 +1746,7 @@ 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;
