[PATCH v3 4/9] scsi: ufshpb: Make eviction depends on region's reads
From: Avri Altman <avri.altman@wdc.com>
Date: 2021-02-18 15:47:30
Also in:
lkml
Subsystem:
scsi subsystem, the rest · Maintainers:
"James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
In host mode, eviction is considered an extreme measure. verify that the entering region has enough reads, and the exiting region has much less reads. Signed-off-by: Avri Altman <avri.altman@wdc.com> --- drivers/scsi/ufs/ufshpb.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index 348185964c32..9cb17c97cf93 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c@@ -17,6 +17,7 @@ #include "../sd.h" #define ACTIVATION_THRESHOLD 4 /* 4 IOs */ +#define EVICTION_THRESHOLD (ACTIVATION_THRESHOLD << 6) /* 256 IOs */ /* memory management */ static struct kmem_cache *ufshpb_mctx_cache;
@@ -995,6 +996,13 @@ static struct ufshpb_region *ufshpb_victim_lru_info(struct ufshpb_lu *hpb) if (ufshpb_check_srgns_issue_state(hpb, rgn)) continue; + /* + * in host control mode, verify that the exiting region + * has less reads + */ + if (hpb->is_hcm && rgn->reads > (EVICTION_THRESHOLD >> 1)) + continue; + victim_rgn = rgn; break; }
@@ -1150,7 +1158,7 @@ static int ufshpb_issue_map_req(struct ufshpb_lu *hpb, static int ufshpb_add_region(struct ufshpb_lu *hpb, struct ufshpb_region *rgn) { - struct ufshpb_region *victim_rgn; + struct ufshpb_region *victim_rgn = NULL; struct victim_select_info *lru_info = &hpb->lru_info; unsigned long flags; int ret = 0;
@@ -1178,6 +1186,16 @@ static int ufshpb_add_region(struct ufshpb_lu *hpb, struct ufshpb_region *rgn) * because the device could detect this region * by not issuing HPB_READ */ + + /* + * in host control mode, verify that the entering + * region has enough reads + */ + if (hpb->is_hcm && rgn->reads < EVICTION_THRESHOLD) { + ret = -EACCES; + goto out; + } + victim_rgn = ufshpb_victim_lru_info(hpb); if (!victim_rgn) { dev_warn(&hpb->sdev_ufs_lu->sdev_dev,
--
2.25.1