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path: root/drivers/scsi/ufs/ufshcd.c
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Diffstat (limited to 'drivers/scsi/ufs/ufshcd.c')
-rw-r--r--drivers/scsi/ufs/ufshcd.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 605ca60e8a10..64b1b2ba3a44 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -39,6 +39,7 @@
#include <linux/async.h>
#include <linux/devfreq.h>
+#include <linux/blkdev.h>
#include "ufshcd.h"
#include "unipro.h"
@@ -1313,6 +1314,16 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
clear_bit_unlock(tag, &hba->lrb_in_use);
goto out;
}
+ /* IO svc time latency histogram */
+ if (hba != NULL && cmd->request != NULL) {
+ if (hba->latency_hist_enabled &&
+ (cmd->request->cmd_type == REQ_TYPE_FS)) {
+ cmd->request->lat_hist_io_start = ktime_get();
+ cmd->request->lat_hist_enabled = 1;
+ } else
+ cmd->request->lat_hist_enabled = 0;
+ }
+
WARN_ON(hba->clk_gating.state != CLKS_ON);
lrbp = &hba->lrb[tag];
@@ -3051,6 +3062,7 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
u32 tr_doorbell;
int result;
int index;
+ struct request *req;
/* Resetting interrupt aggregation counters first and reading the
* DOOR_BELL afterward allows us to handle all the completed requests.
@@ -3074,6 +3086,22 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
/* Mark completed command as NULL in LRB */
lrbp->cmd = NULL;
clear_bit_unlock(index, &hba->lrb_in_use);
+ req = cmd->request;
+ if (req) {
+ /* Update IO svc time latency histogram */
+ if (req->lat_hist_enabled) {
+ ktime_t completion;
+ u_int64_t delta_us;
+
+ completion = ktime_get();
+ delta_us = ktime_us_delta(completion,
+ req->lat_hist_io_start);
+ /* rq_data_dir() => true if WRITE */
+ blk_update_latency_hist(&hba->io_lat_s,
+ (rq_data_dir(req) == READ),
+ delta_us);
+ }
+ }
/* Do not touch lrbp after scsi done */
cmd->scsi_done(cmd);
__ufshcd_release(hba);
@@ -5248,6 +5276,54 @@ out:
}
EXPORT_SYMBOL(ufshcd_shutdown);
+/*
+ * Values permitted 0, 1, 2.
+ * 0 -> Disable IO latency histograms (default)
+ * 1 -> Enable IO latency histograms
+ * 2 -> Zero out IO latency histograms
+ */
+static ssize_t
+latency_hist_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ long value;
+
+ if (kstrtol(buf, 0, &value))
+ return -EINVAL;
+ if (value == BLK_IO_LAT_HIST_ZERO)
+ blk_zero_latency_hist(&hba->io_lat_s);
+ else if (value == BLK_IO_LAT_HIST_ENABLE ||
+ value == BLK_IO_LAT_HIST_DISABLE)
+ hba->latency_hist_enabled = value;
+ return count;
+}
+
+ssize_t
+latency_hist_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return blk_latency_hist_show(&hba->io_lat_s, buf);
+}
+
+static DEVICE_ATTR(latency_hist, S_IRUGO | S_IWUSR,
+ latency_hist_show, latency_hist_store);
+
+static void
+ufshcd_init_latency_hist(struct ufs_hba *hba)
+{
+ if (device_create_file(hba->dev, &dev_attr_latency_hist))
+ dev_err(hba->dev, "Failed to create latency_hist sysfs entry\n");
+}
+
+static void
+ufshcd_exit_latency_hist(struct ufs_hba *hba)
+{
+ device_create_file(hba->dev, &dev_attr_latency_hist);
+}
+
/**
* ufshcd_remove - de-allocate SCSI host and host memory space
* data structure memory
@@ -5263,6 +5339,7 @@ void ufshcd_remove(struct ufs_hba *hba)
scsi_host_put(hba->host);
ufshcd_exit_clk_gating(hba);
+ ufshcd_exit_latency_hist(hba);
if (ufshcd_is_clkscaling_enabled(hba))
devfreq_remove_device(hba->devfreq);
ufshcd_hba_exit(hba);
@@ -5552,6 +5629,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
/* Hold auto suspend until async scan completes */
pm_runtime_get_sync(dev);
+ ufshcd_init_latency_hist(hba);
+
/*
* The device-initialize-sequence hasn't been invoked yet.
* Set the device to power-off state
@@ -5566,6 +5645,7 @@ out_remove_scsi_host:
scsi_remove_host(hba->host);
exit_gating:
ufshcd_exit_clk_gating(hba);
+ ufshcd_exit_latency_hist(hba);
out_disable:
hba->is_irq_enabled = false;
scsi_host_put(host);