Commit 13c044e9 authored by Avri Altman's avatar Avri Altman Committed by Martin K. Petersen
Browse files

scsi: ufs: ufshpb: Add "cold" regions timer 

In order not to hang on to "cold" regions, we inactivate a region that has
had no READ access for a predefined amount of time - READ_TO_MS. For that
purpose monitor the active regions list, polling it on every
POLLING_INTERVAL_MS. On timeout expiry add the region to the
"to-be-inactivated" list unless it is clean and did not exhaust its
READ_TO_EXPIRIES - another parameter.

None of this applies to pinned regions.

Link: https://lore.kernel.org/r/20210712095039.8093-9-avri.altman@wdc.com


Reviewed-by: default avatarDaejun Park <daejun7.park@samsung.com>
Signed-off-by: default avatarAvri Altman <avri.altman@wdc.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 67001ff1

drivers/scsi/ufs/ufshpb.c

+71 −3
Original line number Diff line number Diff line
@@ -18,6 +18,9 @@ 


#define ACTIVATION_THRESHOLD 8 /* 8 IOs */

#define EVICTION_THRESHOLD (ACTIVATION_THRESHOLD << 5) /* 256 IOs */

#define READ_TO_MS 1000

#define READ_TO_EXPIRIES 100

#define POLLING_INTERVAL_MS 200



/* memory management */

static struct kmem_cache *ufshpb_mctx_cache;
@@ -1032,12 +1035,63 @@ static int ufshpb_check_srgns_issue_state(struct ufshpb_lu *hpb, 
	return 0;

}



static void ufshpb_read_to_handler(struct work_struct *work)

{

	struct ufshpb_lu *hpb = container_of(work, struct ufshpb_lu,

					     ufshpb_read_to_work.work);

	struct victim_select_info *lru_info = &hpb->lru_info;

	struct ufshpb_region *rgn, *next_rgn;

	unsigned long flags;

	LIST_HEAD(expired_list);



	if (test_and_set_bit(TIMEOUT_WORK_RUNNING, &hpb->work_data_bits))

		return;



	spin_lock_irqsave(&hpb->rgn_state_lock, flags);



	list_for_each_entry_safe(rgn, next_rgn, &lru_info->lh_lru_rgn,

				 list_lru_rgn) {

		bool timedout = ktime_after(ktime_get(), rgn->read_timeout);



		if (timedout) {

			rgn->read_timeout_expiries--;

			if (is_rgn_dirty(rgn) ||

			    rgn->read_timeout_expiries == 0)

				list_add(&rgn->list_expired_rgn, &expired_list);

			else

				rgn->read_timeout = ktime_add_ms(ktime_get(),

							 READ_TO_MS);

		}

	}



	spin_unlock_irqrestore(&hpb->rgn_state_lock, flags);



	list_for_each_entry_safe(rgn, next_rgn, &expired_list,

				 list_expired_rgn) {

		list_del_init(&rgn->list_expired_rgn);

		spin_lock_irqsave(&hpb->rsp_list_lock, flags);

		ufshpb_update_inactive_info(hpb, rgn->rgn_idx);

		spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);

	}



	ufshpb_kick_map_work(hpb);



	clear_bit(TIMEOUT_WORK_RUNNING, &hpb->work_data_bits);



	schedule_delayed_work(&hpb->ufshpb_read_to_work,

			      msecs_to_jiffies(POLLING_INTERVAL_MS));

}



static void ufshpb_add_lru_info(struct victim_select_info *lru_info,

				struct ufshpb_region *rgn)

{

	rgn->rgn_state = HPB_RGN_ACTIVE;

	list_add_tail(&rgn->list_lru_rgn, &lru_info->lh_lru_rgn);

	atomic_inc(&lru_info->active_cnt);

	if (rgn->hpb->is_hcm) {

		rgn->read_timeout = ktime_add_ms(ktime_get(), READ_TO_MS);

		rgn->read_timeout_expiries = READ_TO_EXPIRIES;

	}

}



static void ufshpb_hit_lru_info(struct victim_select_info *lru_info,
@@ -1819,6 +1873,7 @@ static int ufshpb_alloc_region_tbl(struct ufs_hba *hba, struct ufshpb_lu *hpb) 


		INIT_LIST_HEAD(&rgn->list_inact_rgn);

		INIT_LIST_HEAD(&rgn->list_lru_rgn);

		INIT_LIST_HEAD(&rgn->list_expired_rgn);



		if (rgn_idx == hpb->rgns_per_lu - 1) {

			srgn_cnt = ((hpb->srgns_per_lu - 1) %
@@ -1840,6 +1895,7 @@ static int ufshpb_alloc_region_tbl(struct ufs_hba *hba, struct ufshpb_lu *hpb) 
		}



		rgn->rgn_flags = 0;

		rgn->hpb = hpb;

	}



	return 0;
@@ -2063,9 +2119,12 @@ static int ufshpb_lu_hpb_init(struct ufs_hba *hba, struct ufshpb_lu *hpb) 
	INIT_LIST_HEAD(&hpb->list_hpb_lu);



	INIT_WORK(&hpb->map_work, ufshpb_map_work_handler);

	if (hpb->is_hcm)

	if (hpb->is_hcm) {

		INIT_WORK(&hpb->ufshpb_normalization_work,

			  ufshpb_normalization_work_handler);

		INIT_DELAYED_WORK(&hpb->ufshpb_read_to_work,

				  ufshpb_read_to_handler);

	}



	hpb->map_req_cache = kmem_cache_create("ufshpb_req_cache",

			  sizeof(struct ufshpb_req), 0, 0, NULL);
@@ -2099,6 +2158,10 @@ static int ufshpb_lu_hpb_init(struct ufs_hba *hba, struct ufshpb_lu *hpb) 
	ufshpb_stat_init(hpb);

	ufshpb_param_init(hpb);



	if (hpb->is_hcm)

		schedule_delayed_work(&hpb->ufshpb_read_to_work,

				      msecs_to_jiffies(POLLING_INTERVAL_MS));



	return 0;



release_pre_req_mempool:
@@ -2165,9 +2228,10 @@ static void ufshpb_discard_rsp_lists(struct ufshpb_lu *hpb) 


static void ufshpb_cancel_jobs(struct ufshpb_lu *hpb)

{

	if (hpb->is_hcm)

	if (hpb->is_hcm) {

		cancel_delayed_work_sync(&hpb->ufshpb_read_to_work);

		cancel_work_sync(&hpb->ufshpb_normalization_work);



	}

	cancel_work_sync(&hpb->map_work);

}
@@ -2275,6 +2339,10 @@ void ufshpb_resume(struct ufs_hba *hba) 
			continue;

		ufshpb_set_state(hpb, HPB_PRESENT);

		ufshpb_kick_map_work(hpb);

		if (hpb->is_hcm)

			schedule_delayed_work(&hpb->ufshpb_read_to_work,

				msecs_to_jiffies(POLLING_INTERVAL_MS));



	}

}

drivers/scsi/ufs/ufshpb.h

+8 −0
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ struct ufshpb_subregion { 
};



struct ufshpb_region {

	struct ufshpb_lu *hpb;

	struct ufshpb_subregion *srgn_tbl;

	enum HPB_RGN_STATE rgn_state;

	int rgn_idx;
@@ -132,6 +133,10 @@ struct ufshpb_region { 
	/* region reads - for host mode */

	spinlock_t rgn_lock;

	unsigned int reads;

	/* region "cold" timer - for host mode */

	ktime_t read_timeout;

	unsigned int read_timeout_expiries;

	struct list_head list_expired_rgn;

};



#define for_each_sub_region(rgn, i, srgn)				\
@@ -223,6 +228,9 @@ struct ufshpb_lu { 
	/* for selecting victim */

	struct victim_select_info lru_info;

	struct work_struct ufshpb_normalization_work;

	struct delayed_work ufshpb_read_to_work;

	unsigned long work_data_bits;

#define TIMEOUT_WORK_RUNNING 0



	/* pinned region information */

	u32 lu_pinned_start;