[PATCH 1/2] habanalabs: add uapi to retrieve device utilization

From: Oded Gabbay
Date: Fri Aug 30 2019 - 06:57:13 EST


Users and sysadmins usually want to know what is the device utilization as
a level 0 indication if they are efficiently using the device.

Add a new opcode to the INFO IOCTL that will return the device utilization
over the last period of 100-1000ms. The return value is 0-100,
representing as percentage the total utilization rate.

Signed-off-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>
---
drivers/misc/habanalabs/command_submission.c | 20 +++-
drivers/misc/habanalabs/device.c | 114 ++++++++++++++++++-
drivers/misc/habanalabs/habanalabs.h | 23 +++-
drivers/misc/habanalabs/habanalabs_ioctl.c | 27 +++++
drivers/misc/habanalabs/hw_queue.c | 8 +-
drivers/misc/habanalabs/include/goya/goya.h | 2 +
include/uapi/misc/habanalabs.h | 49 +++++---
7 files changed, 220 insertions(+), 23 deletions(-)

diff --git a/drivers/misc/habanalabs/command_submission.c b/drivers/misc/habanalabs/command_submission.c
index e4dd3e83df8b..4777ec4c2b55 100644
--- a/drivers/misc/habanalabs/command_submission.c
+++ b/drivers/misc/habanalabs/command_submission.c
@@ -178,11 +178,23 @@ static void cs_do_release(struct kref *ref)

/* We also need to update CI for internal queues */
if (cs->submitted) {
- int cs_cnt = atomic_dec_return(&hdev->cs_active_cnt);
+ hdev->asic_funcs->hw_queues_lock(hdev);

- WARN_ONCE((cs_cnt < 0),
- "hl%d: error in CS active cnt %d\n",
- hdev->id, cs_cnt);
+ hdev->cs_active_cnt--;
+ if (!hdev->cs_active_cnt) {
+ struct hl_device_idle_busy_ts *ts;
+
+ ts = &hdev->idle_busy_ts_arr[hdev->idle_busy_ts_idx++];
+ ts->busy_to_idle_ts = ktime_get();
+
+ if (hdev->idle_busy_ts_idx == HL_IDLE_BUSY_TS_ARR_SIZE)
+ hdev->idle_busy_ts_idx = 0;
+ } else if (hdev->cs_active_cnt < 0) {
+ dev_crit(hdev->dev, "CS active cnt %d is negative\n",
+ hdev->cs_active_cnt);
+ }
+
+ hdev->asic_funcs->hw_queues_unlock(hdev);

hl_int_hw_queue_update_ci(cs);

diff --git a/drivers/misc/habanalabs/device.c b/drivers/misc/habanalabs/device.c
index 41c3ddbca351..bc98032cc4ec 100644
--- a/drivers/misc/habanalabs/device.c
+++ b/drivers/misc/habanalabs/device.c
@@ -293,6 +293,14 @@ static int device_early_init(struct hl_device *hdev)
goto free_eq_wq;
}

+ hdev->idle_busy_ts_arr = kmalloc_array(HL_IDLE_BUSY_TS_ARR_SIZE,
+ sizeof(struct hl_device_idle_busy_ts),
+ (GFP_KERNEL | __GFP_ZERO));
+ if (!hdev->idle_busy_ts_arr) {
+ rc = -ENOMEM;
+ goto free_chip_info;
+ }
+
hl_cb_mgr_init(&hdev->kernel_cb_mgr);

mutex_init(&hdev->send_cpu_message_lock);
@@ -303,10 +311,11 @@ static int device_early_init(struct hl_device *hdev)
INIT_LIST_HEAD(&hdev->fpriv_list);
mutex_init(&hdev->fpriv_list_lock);
atomic_set(&hdev->in_reset, 0);
- atomic_set(&hdev->cs_active_cnt, 0);

return 0;

+free_chip_info:
+ kfree(hdev->hl_chip_info);
free_eq_wq:
destroy_workqueue(hdev->eq_wq);
free_cq_wq:
@@ -336,6 +345,7 @@ static void device_early_fini(struct hl_device *hdev)

hl_cb_mgr_fini(hdev, &hdev->kernel_cb_mgr);

+ kfree(hdev->idle_busy_ts_arr);
kfree(hdev->hl_chip_info);

destroy_workqueue(hdev->eq_wq);
@@ -451,6 +461,100 @@ static void device_late_fini(struct hl_device *hdev)
hdev->late_init_done = false;
}

+uint32_t hl_device_utilization(struct hl_device *hdev, uint32_t period_ms)
+{
+ struct hl_device_idle_busy_ts *ts;
+ ktime_t zero_ktime, curr = ktime_get();
+ u32 overlap_cnt = 0, last_index = hdev->idle_busy_ts_idx;
+ s64 period_us, last_start_us, last_end_us, last_busy_time_us,
+ total_busy_time_us = 0;
+
+ zero_ktime = ktime_set(0, 0);
+ period_us = period_ms * USEC_PER_MSEC;
+ ts = &hdev->idle_busy_ts_arr[last_index];
+
+ /* check case that device is currently in idle */
+ if (!ktime_compare(ts->busy_to_idle_ts, zero_ktime) &&
+ !ktime_compare(ts->idle_to_busy_ts, zero_ktime)) {
+
+ last_index--;
+ /* Handle case idle_busy_ts_idx was 0 */
+ if (last_index > HL_IDLE_BUSY_TS_ARR_SIZE)
+ last_index = HL_IDLE_BUSY_TS_ARR_SIZE - 1;
+
+ ts = &hdev->idle_busy_ts_arr[last_index];
+ }
+
+ while (overlap_cnt < HL_IDLE_BUSY_TS_ARR_SIZE) {
+ /* Check if we are in last sample case. i.e. if the sample
+ * begun before the sampling period. This could be a real
+ * sample or 0 so need to handle both cases
+ */
+ last_start_us = ktime_to_us(
+ ktime_sub(curr, ts->idle_to_busy_ts));
+
+ if (last_start_us > period_us) {
+
+ /* First check two cases:
+ * 1. If the device is currently busy
+ * 2. If the device was idle during the whole sampling
+ * period
+ */
+
+ if (!ktime_compare(ts->busy_to_idle_ts, zero_ktime)) {
+ /* Check if the device is currently busy */
+ if (ktime_compare(ts->idle_to_busy_ts,
+ zero_ktime))
+ return 100;
+
+ /* We either didn't have any activity or we
+ * reached an entry which is 0. Either way,
+ * exit and return what was accumulated so far
+ */
+ break;
+ }
+
+ /* If sample has finished, check it is relevant */
+ last_end_us = ktime_to_us(
+ ktime_sub(curr, ts->busy_to_idle_ts));
+
+ if (last_end_us > period_us)
+ break;
+
+ /* It is relevant so add it but with adjustment */
+ last_busy_time_us = ktime_to_us(
+ ktime_sub(ts->busy_to_idle_ts,
+ ts->idle_to_busy_ts));
+ total_busy_time_us += last_busy_time_us -
+ (last_start_us - period_us);
+ break;
+ }
+
+ /* Check if the sample is finished or still open */
+ if (ktime_compare(ts->busy_to_idle_ts, zero_ktime))
+ last_busy_time_us = ktime_to_us(
+ ktime_sub(ts->busy_to_idle_ts,
+ ts->idle_to_busy_ts));
+ else
+ last_busy_time_us = ktime_to_us(
+ ktime_sub(curr, ts->idle_to_busy_ts));
+
+ total_busy_time_us += last_busy_time_us;
+
+ last_index--;
+ /* Handle case idle_busy_ts_idx was 0 */
+ if (last_index > HL_IDLE_BUSY_TS_ARR_SIZE)
+ last_index = HL_IDLE_BUSY_TS_ARR_SIZE - 1;
+
+ ts = &hdev->idle_busy_ts_arr[last_index];
+
+ overlap_cnt++;
+ };
+
+ return DIV_ROUND_UP(((total_busy_time_us / USEC_PER_MSEC) * 100),
+ period_ms);
+}
+
/*
* hl_device_set_frequency - set the frequency of the device
*
@@ -808,6 +912,14 @@ int hl_device_reset(struct hl_device *hdev, bool hard_reset,
for (i = 0 ; i < hdev->asic_prop.completion_queues_count ; i++)
hl_cq_reset(hdev, &hdev->completion_queue[i]);

+ hdev->idle_busy_ts_idx = 0;
+ hdev->idle_busy_ts_arr[0].busy_to_idle_ts = ktime_set(0, 0);
+ hdev->idle_busy_ts_arr[0].idle_to_busy_ts = ktime_set(0, 0);
+
+ if (hdev->cs_active_cnt)
+ dev_crit(hdev->dev, "CS active cnt %d is not 0 during reset\n",
+ hdev->cs_active_cnt);
+
mutex_lock(&hdev->fpriv_list_lock);

/* Make sure the context switch phase will run again */
diff --git a/drivers/misc/habanalabs/habanalabs.h b/drivers/misc/habanalabs/habanalabs.h
index a4d929f5bad8..23b86b7f9732 100644
--- a/drivers/misc/habanalabs/habanalabs.h
+++ b/drivers/misc/habanalabs/habanalabs.h
@@ -45,6 +45,8 @@
/* MUST BE POWER OF 2 and larger than 1 */
#define HL_MAX_PENDING_CS 64

+#define HL_IDLE_BUSY_TS_ARR_SIZE 4096
+
/* Memory */
#define MEM_HASH_TABLE_BITS 7 /* 1 << 7 buckets */

@@ -1156,6 +1158,16 @@ struct hl_device_reset_work {
struct hl_device *hdev;
};

+/**
+ * struct hl_device_idle_busy_ts - used for calculating device utilization rate.
+ * @idle_to_busy_ts: timestamp where device changed from idle to busy.
+ * @busy_to_idle_ts: timestamp where device changed from busy to idle.
+ */
+struct hl_device_idle_busy_ts {
+ ktime_t idle_to_busy_ts;
+ ktime_t busy_to_idle_ts;
+};
+
/**
* struct hl_device - habanalabs device structure.
* @pdev: pointer to PCI device, can be NULL in case of simulator device.
@@ -1203,19 +1215,22 @@ struct hl_device_reset_work {
* when a user opens the device
* @fpriv_list_lock: protects the fpriv_list
* @compute_ctx: current compute context executing.
+ * @idle_busy_ts_arr: array to hold time stamps of transitions from idle to busy
+ * and vice-versa
* @dram_used_mem: current DRAM memory consumption.
* @timeout_jiffies: device CS timeout value.
* @max_power: the max power of the device, as configured by the sysadmin. This
* value is saved so in case of hard-reset, KMD will restore this
* value and update the F/W after the re-initialization
* @in_reset: is device in reset flow.
+ * @curr_pll_profile: current PLL profile.
* @cs_active_cnt: number of active command submissions on this device (active
* means already in H/W queues)
- * @curr_pll_profile: current PLL profile.
* @major: habanalabs KMD major.
* @high_pll: high PLL profile frequency.
* @soft_reset_cnt: number of soft reset since KMD loading.
* @hard_reset_cnt: number of hard reset since KMD loading.
+ * @idle_busy_ts_idx: index of current entry in idle_busy_ts_arr
* @id: device minor.
* @id_control: minor of the control device
* @disabled: is device disabled.
@@ -1285,16 +1300,19 @@ struct hl_device {

struct hl_ctx *compute_ctx;

+ struct hl_device_idle_busy_ts *idle_busy_ts_arr;
+
atomic64_t dram_used_mem;
u64 timeout_jiffies;
u64 max_power;
atomic_t in_reset;
- atomic_t cs_active_cnt;
enum hl_pll_frequency curr_pll_profile;
+ int cs_active_cnt;
u32 major;
u32 high_pll;
u32 soft_reset_cnt;
u32 hard_reset_cnt;
+ u32 idle_busy_ts_idx;
u16 id;
u16 id_control;
u8 disabled;
@@ -1457,6 +1475,7 @@ int hl_device_reset(struct hl_device *hdev, bool hard_reset,
void hl_hpriv_get(struct hl_fpriv *hpriv);
void hl_hpriv_put(struct hl_fpriv *hpriv);
int hl_device_set_frequency(struct hl_device *hdev, enum hl_pll_frequency freq);
+uint32_t hl_device_utilization(struct hl_device *hdev, uint32_t period_ms);

int hl_build_hwmon_channel_info(struct hl_device *hdev,
struct armcp_sensor *sensors_arr);
diff --git a/drivers/misc/habanalabs/habanalabs_ioctl.c b/drivers/misc/habanalabs/habanalabs_ioctl.c
index d894873ca2d1..6325e98a5ae9 100644
--- a/drivers/misc/habanalabs/habanalabs_ioctl.c
+++ b/drivers/misc/habanalabs/habanalabs_ioctl.c
@@ -197,6 +197,29 @@ static int debug_coresight(struct hl_device *hdev, struct hl_debug_args *args)
return rc;
}

+static int device_utilization(struct hl_device *hdev, struct hl_info_args *args)
+{
+ struct hl_info_device_utilization device_util = {0};
+ u32 max_size = args->return_size;
+ void __user *out = (void __user *) (uintptr_t) args->return_pointer;
+
+ if ((!max_size) || (!out))
+ return -EINVAL;
+
+ if ((args->period_ms < 100) || (args->period_ms > 1000) ||
+ (args->period_ms % 100)) {
+ dev_err(hdev->dev,
+ "period %u must be between 100 - 1000 and must be divisible by 100\n",
+ args->period_ms);
+ return -EINVAL;
+ }
+
+ device_util.utilization = hl_device_utilization(hdev, args->period_ms);
+
+ return copy_to_user(out, &device_util,
+ min((size_t) max_size, sizeof(device_util))) ? -EFAULT : 0;
+}
+
static int _hl_info_ioctl(struct hl_fpriv *hpriv, void *data,
struct device *dev)
{
@@ -239,6 +262,10 @@ static int _hl_info_ioctl(struct hl_fpriv *hpriv, void *data,
rc = hw_idle(hdev, args);
break;

+ case HL_INFO_DEVICE_UTILIZATION:
+ rc = device_utilization(hdev, args);
+ break;
+
default:
dev_err(dev, "Invalid request %d\n", args->op);
rc = -ENOTTY;
diff --git a/drivers/misc/habanalabs/hw_queue.c b/drivers/misc/habanalabs/hw_queue.c
index 696cf7d206c6..55b383b2a116 100644
--- a/drivers/misc/habanalabs/hw_queue.c
+++ b/drivers/misc/habanalabs/hw_queue.c
@@ -364,7 +364,13 @@ int hl_hw_queue_schedule_cs(struct hl_cs *cs)
spin_unlock(&hdev->hw_queues_mirror_lock);
}

- atomic_inc(&hdev->cs_active_cnt);
+ if (!hdev->cs_active_cnt++) {
+ struct hl_device_idle_busy_ts *ts;
+
+ ts = &hdev->idle_busy_ts_arr[hdev->idle_busy_ts_idx];
+ ts->busy_to_idle_ts = ktime_set(0, 0);
+ ts->idle_to_busy_ts = ktime_get();
+ }

list_for_each_entry_safe(job, tmp, &cs->job_list, cs_node)
if (job->ext_queue)
diff --git a/drivers/misc/habanalabs/include/goya/goya.h b/drivers/misc/habanalabs/include/goya/goya.h
index 3f02a52ba4ce..43d241891e45 100644
--- a/drivers/misc/habanalabs/include/goya/goya.h
+++ b/drivers/misc/habanalabs/include/goya/goya.h
@@ -38,4 +38,6 @@

#define TPC_MAX_NUM 8

+#define MME_MAX_NUM 1
+
#endif /* GOYA_H */
diff --git a/include/uapi/misc/habanalabs.h b/include/uapi/misc/habanalabs.h
index 266bf85056d4..73ee212d7fa6 100644
--- a/include/uapi/misc/habanalabs.h
+++ b/include/uapi/misc/habanalabs.h
@@ -77,22 +77,29 @@ enum hl_device_status {

/* Opcode for management ioctl
*
- * HW_IP_INFO - Receive information about different IP blocks in the
- * device.
- * HL_INFO_HW_EVENTS - Receive an array describing how many times each event
- * occurred since the last hard reset.
- * HL_INFO_DRAM_USAGE - Retrieve the dram usage inside the device and of the
- * specific context. This is relevant only for GOYA device.
- * HL_INFO_HW_IDLE - Retrieve information about the idle status of each
- * internal engine.
+ * HW_IP_INFO - Receive information about different IP blocks in the
+ * device.
+ * HL_INFO_HW_EVENTS - Receive an array describing how many times each event
+ * occurred since the last hard reset.
+ * HL_INFO_DRAM_USAGE - Retrieve the dram usage inside the device and of the
+ * specific context. This is relevant only for devices
+ * where the dram is managed by the kernel driver
+ * HL_INFO_HW_IDLE - Retrieve information about the idle status of each
+ * internal engine.
* HL_INFO_DEVICE_STATUS - Retrieve the device's status. This opcode doesn't
* require an open context.
+ * HL_INFO_DEVICE_UTILIZATION - Retrieve the total utilization of the device
+ * over the last period specified by the user.
+ * The period can be between 100ms to 1s, in
+ * resolution of 100ms. The return value is a
+ * percentage of the utilization rate.
*/
-#define HL_INFO_HW_IP_INFO 0
-#define HL_INFO_HW_EVENTS 1
-#define HL_INFO_DRAM_USAGE 2
-#define HL_INFO_HW_IDLE 3
-#define HL_INFO_DEVICE_STATUS 4
+#define HL_INFO_HW_IP_INFO 0
+#define HL_INFO_HW_EVENTS 1
+#define HL_INFO_DRAM_USAGE 2
+#define HL_INFO_HW_IDLE 3
+#define HL_INFO_DEVICE_STATUS 4
+#define HL_INFO_DEVICE_UTILIZATION 6

#define HL_INFO_VERSION_MAX_LEN 128

@@ -134,6 +141,11 @@ struct hl_info_device_status {
__u32 pad;
};

+struct hl_info_device_utilization {
+ __u32 utilization;
+ __u32 pad;
+};
+
struct hl_info_args {
/* Location of relevant struct in userspace */
__u64 return_pointer;
@@ -149,8 +161,15 @@ struct hl_info_args {
/* HL_INFO_* */
__u32 op;

- /* Context ID - Currently not in use */
- __u32 ctx_id;
+ union {
+ /* Context ID - Currently not in use */
+ __u32 ctx_id;
+ /* Period value for utilization rate (100ms - 1000ms, in 100ms
+ * resolution.
+ */
+ __u32 period_ms;
+ };
+
__u32 pad;
};

--
2.17.1