#include "blk.h"
#include "blk-mq.h"
+#include <linux/math64.h>
+
EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap);
EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);
EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);
return 0;
}
+
+/*
+ * Blk IO latency support. We want this to be as cheap as possible, so doing
+ * this lockless (and avoiding atomics), a few off by a few errors in this
+ * code is not harmful, and we don't want to do anything that is
+ * perf-impactful.
+ * TODO : If necessary, we can make the histograms per-cpu and aggregate
+ * them when printing them out.
+ */
+void
+blk_zero_latency_hist(struct io_latency_state *s)
+{
+ memset(s->latency_y_axis_read, 0,
+ sizeof(s->latency_y_axis_read));
+ memset(s->latency_y_axis_write, 0,
+ sizeof(s->latency_y_axis_write));
+ s->latency_reads_elems = 0;
+ s->latency_writes_elems = 0;
+}
+
+ssize_t
+blk_latency_hist_show(struct io_latency_state *s, char *buf)
+{
+ int i;
+ int bytes_written = 0;
+ u_int64_t num_elem, elem;
+ int pct;
+
+ num_elem = s->latency_reads_elems;
+ if (num_elem > 0) {
+ bytes_written += scnprintf(buf + bytes_written,
+ PAGE_SIZE - bytes_written,
+ "IO svc_time Read Latency Histogram (n = %llu):\n",
+ num_elem);
+ for (i = 0;
+ i < ARRAY_SIZE(latency_x_axis_us);
+ i++) {
+ elem = s->latency_y_axis_read[i];
+ pct = div64_u64(elem * 100, num_elem);
+ bytes_written += scnprintf(buf + bytes_written,
+ PAGE_SIZE - bytes_written,
+ "\t< %5lluus%15llu%15d%%\n",
+ latency_x_axis_us[i],
+ elem, pct);
+ }
+ /* Last element in y-axis table is overflow */
+ elem = s->latency_y_axis_read[i];
+ pct = div64_u64(elem * 100, num_elem);
+ bytes_written += scnprintf(buf + bytes_written,
+ PAGE_SIZE - bytes_written,
+ "\t> %5dms%15llu%15d%%\n", 10,
+ elem, pct);
+ }
+ num_elem = s->latency_writes_elems;
+ if (num_elem > 0) {
+ bytes_written += scnprintf(buf + bytes_written,
+ PAGE_SIZE - bytes_written,
+ "IO svc_time Write Latency Histogram (n = %llu):\n",
+ num_elem);
+ for (i = 0;
+ i < ARRAY_SIZE(latency_x_axis_us);
+ i++) {
+ elem = s->latency_y_axis_write[i];
+ pct = div64_u64(elem * 100, num_elem);
+ bytes_written += scnprintf(buf + bytes_written,
+ PAGE_SIZE - bytes_written,
+ "\t< %5lluus%15llu%15d%%\n",
+ latency_x_axis_us[i],
+ elem, pct);
+ }
+ /* Last element in y-axis table is overflow */
+ elem = s->latency_y_axis_write[i];
+ pct = div64_u64(elem * 100, num_elem);
+ bytes_written += scnprintf(buf + bytes_written,
+ PAGE_SIZE - bytes_written,
+ "\t> %5dms%15llu%15d%%\n", 10,
+ elem, pct);
+ }
+ return bytes_written;
+}
pr_debug("%s: %d bytes transferred: %d\n",
mmc_hostname(host),
mrq->data->bytes_xfered, mrq->data->error);
+ if (mrq->lat_hist_enabled) {
+ ktime_t completion;
+ u_int64_t delta_us;
+
+ completion = ktime_get();
+ delta_us = ktime_us_delta(completion,
+ mrq->io_start);
+ blk_update_latency_hist(&host->io_lat_s,
+ (mrq->data->flags & MMC_DATA_READ),
+ delta_us);
+ }
trace_mmc_blk_rw_end(cmd->opcode, cmd->arg, mrq->data);
}
}
if (!err && areq) {
+ if (host->latency_hist_enabled) {
+ areq->mrq->io_start = ktime_get();
+ areq->mrq->lat_hist_enabled = 1;
+ } else
+ areq->mrq->lat_hist_enabled = 0;
trace_mmc_blk_rw_start(areq->mrq->cmd->opcode,
areq->mrq->cmd->arg,
areq->mrq->data);
}
static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
- unsigned int arg, unsigned int qty)
+ unsigned int arg, unsigned int qty)
{
unsigned int erase_timeout;
destroy_workqueue(workqueue);
}
+static ssize_t
+latency_hist_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct mmc_host *host = cls_dev_to_mmc_host(dev);
+
+ return blk_latency_hist_show(&host->io_lat_s, buf);
+}
+
+/*
+ * 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 mmc_host *host = cls_dev_to_mmc_host(dev);
+ long value;
+
+ if (kstrtol(buf, 0, &value))
+ return -EINVAL;
+ if (value == BLK_IO_LAT_HIST_ZERO)
+ blk_zero_latency_hist(&host->io_lat_s);
+ else if (value == BLK_IO_LAT_HIST_ENABLE ||
+ value == BLK_IO_LAT_HIST_DISABLE)
+ host->latency_hist_enabled = value;
+ return count;
+}
+
+static DEVICE_ATTR(latency_hist, S_IRUGO | S_IWUSR,
+ latency_hist_show, latency_hist_store);
+
+void
+mmc_latency_hist_sysfs_init(struct mmc_host *host)
+{
+ if (device_create_file(&host->class_dev, &dev_attr_latency_hist))
+ dev_err(&host->class_dev,
+ "Failed to create latency_hist sysfs entry\n");
+}
+
+void
+mmc_latency_hist_sysfs_exit(struct mmc_host *host)
+{
+ device_remove_file(&host->class_dev, &dev_attr_latency_hist);
+}
+
subsys_initcall(mmc_init);
module_exit(mmc_exit);
#include "slot-gpio.h"
#include "pwrseq.h"
-#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
-
static DEFINE_IDR(mmc_host_idr);
static DEFINE_SPINLOCK(mmc_host_lock);
mmc_add_host_debugfs(host);
#endif
+ mmc_latency_hist_sysfs_init(host);
+
mmc_start_host(host);
if (!(host->pm_flags & MMC_PM_IGNORE_PM_NOTIFY))
register_pm_notifier(&host->pm_notify);
mmc_remove_host_debugfs(host);
#endif
+ mmc_latency_hist_sysfs_exit(host);
+
device_del(&host->class_dev);
led_trigger_unregister_simple(host->led);
#define _MMC_CORE_HOST_H
#include <linux/mmc/host.h>
+#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
+
int mmc_register_host_class(void);
void mmc_unregister_host_class(void);
void mmc_retune_release(struct mmc_host *host);
int mmc_retune(struct mmc_host *host);
+void mmc_latency_hist_sysfs_init(struct mmc_host *host);
+void mmc_latency_hist_sysfs_exit(struct mmc_host *host);
+
#endif
#include <linux/async.h>
#include <linux/devfreq.h>
+#include <linux/blkdev.h>
#include "ufshcd.h"
#include "unipro.h"
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];
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.
/* 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);
}
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
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);
/* 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
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);
struct devfreq *devfreq;
struct ufs_clk_scaling clk_scaling;
bool is_sys_suspended;
+
+ int latency_hist_enabled;
+ struct io_latency_state io_lat_s;
};
/* Returns true if clocks can be gated. Otherwise false */
/* for bidi */
struct request *next_rq;
+
+ ktime_t lat_hist_io_start;
+ int lat_hist_enabled;
};
static inline unsigned short req_get_ioprio(struct request *req)
struct writeback_control *);
extern long bdev_direct_access(struct block_device *, sector_t,
void __pmem **addr, unsigned long *pfn, long size);
+
+/*
+ * X-axis for IO latency histogram support.
+ */
+static const u_int64_t latency_x_axis_us[] = {
+ 100,
+ 200,
+ 300,
+ 400,
+ 500,
+ 600,
+ 700,
+ 800,
+ 900,
+ 1000,
+ 1200,
+ 1400,
+ 1600,
+ 1800,
+ 2000,
+ 2500,
+ 3000,
+ 4000,
+ 5000,
+ 6000,
+ 7000,
+ 9000,
+ 10000
+};
+
+#define BLK_IO_LAT_HIST_DISABLE 0
+#define BLK_IO_LAT_HIST_ENABLE 1
+#define BLK_IO_LAT_HIST_ZERO 2
+
+struct io_latency_state {
+ u_int64_t latency_y_axis_read[ARRAY_SIZE(latency_x_axis_us) + 1];
+ u_int64_t latency_reads_elems;
+ u_int64_t latency_y_axis_write[ARRAY_SIZE(latency_x_axis_us) + 1];
+ u_int64_t latency_writes_elems;
+};
+
+static inline void
+blk_update_latency_hist(struct io_latency_state *s,
+ int read,
+ u_int64_t delta_us)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(latency_x_axis_us); i++) {
+ if (delta_us < (u_int64_t)latency_x_axis_us[i]) {
+ if (read)
+ s->latency_y_axis_read[i]++;
+ else
+ s->latency_y_axis_write[i]++;
+ break;
+ }
+ }
+ if (i == ARRAY_SIZE(latency_x_axis_us)) {
+ /* Overflowed the histogram */
+ if (read)
+ s->latency_y_axis_read[i]++;
+ else
+ s->latency_y_axis_write[i]++;
+ }
+ if (read)
+ s->latency_reads_elems++;
+ else
+ s->latency_writes_elems++;
+}
+
+void blk_zero_latency_hist(struct io_latency_state *s);
+ssize_t blk_latency_hist_show(struct io_latency_state *s, char *buf);
+
#else /* CONFIG_BLOCK */
struct block_device;
struct completion completion;
void (*done)(struct mmc_request *);/* completion function */
struct mmc_host *host;
+ ktime_t io_start;
+ int lat_hist_enabled;
};
struct mmc_card;
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/fault-inject.h>
+#include <linux/blkdev.h>
#include <linux/mmc/core.h>
#include <linux/mmc/card.h>
} embedded_sdio_data;
#endif
+ int latency_hist_enabled;
+ struct io_latency_state io_lat_s;
+
unsigned long private[0] ____cacheline_aligned;
};
projects / firefly-linux-kernel-4.4.55.git / commitdiff