[ Upstream commit 8eb456be75 ]
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: 7252a36030 ("scsi: ufs: Avoid busy-waiting by eliminating tag conflicts")
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
bbab483613