[PATCH 2/2] ufs: don't use the fair tag sharings

From: Ed Tsai
Date: Tue May 09 2023 - 02:53:35 EST


The tags allocation is limited by the fair sharing algorithm. It hurts
the performance for UFS devices, because the queue depth of general I/O
is reduced by half once the UFS send a control command.

Signed-off-by: Ed Tsai <ed.tsai@xxxxxxxxxxxx>
---
drivers/ufs/core/ufshcd.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 17d7bb875fee..e96a50265285 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -5149,6 +5149,9 @@ static int ufshcd_slave_configure(struct scsi_device *sdev)
blk_queue_update_dma_pad(q, PRDT_DATA_BYTE_COUNT_PAD - 1);
if (hba->quirks & UFSHCD_QUIRK_4KB_DMA_ALIGNMENT)
blk_queue_update_dma_alignment(q, 4096 - 1);
+
+ blk_queue_flag_clear(QUEUE_FLAG_FAIR_TAG_SHARING, q);
+
/*
* Block runtime-pm until all consumers are added.
* Refer ufshcd_setup_links().
--
2.18.0