Re: [Intel-gfx] [RFC 4/4] drm/i915/perf: Send system clock monotonic time in perf samples

[Sagar Arun Kamble]

On 12/5/2017 7:52 PM, Lionel Landwerlin wrote:

On 15/11/17 12:13, Sagar Arun Kamble wrote:

From: Sourab Gupta 

Currently, we have the ability to only forward the GPU timestamps in the
samples (which are generated via OA reports). This limits the ability to
correlate these samples with the system events.

An ability is therefore needed to report timestamps in different clock
domains, such as CLOCK_MONOTONIC, in the perf samples to be of more
practical use to the userspace. This ability becomes important
when we want to correlate/plot GPU events/samples with other system 
events

on the same timeline (e.g. vblank events, or timestamps when work was
submitted to kernel, etc.)

The patch here proposes a mechanism to achieve this. The correlation
between gpu time and system time is established using the timestamp 
clock
associated with the command stream, abstracted as 
timecounter/cyclecounter

to retrieve gpu/system time correlated values.

v2: Added i915_driver_init_late() function to capture the new late init
phase for perf (Chris)

v3: Removed cross-timestamp changes.

Signed-off-by: Sourab Gupta 
Signed-off-by: Sagar Arun Kamble 
Cc: Lionel Landwerlin 
Cc: Chris Wilson 
Cc: Sourab Gupta 
Cc: Matthew Auld 
---
  drivers/gpu/drm/i915/i915_perf.c | 27 +++
  include/uapi/drm/i915_drm.h  |  7 +++
  2 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_perf.c 
b/drivers/gpu/drm/i915/i915_perf.c

index 3b721d7..94ee924 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -336,6 +336,7 @@
    #define SAMPLE_OA_REPORT    BIT(0)
  #define SAMPLE_GPU_TS    BIT(1)
+#define SAMPLE_SYSTEM_TS    BIT(2)
    /**
   * struct perf_open_properties - for validated properties given to 
open a stream
@@ -622,6 +623,7 @@ static int append_oa_sample(struct 
i915_perf_stream *stream,

  struct drm_i915_perf_record_header header;
  u32 sample_flags = stream->sample_flags;
  u64 gpu_ts = 0;
+    u64 system_ts = 0;
    header.type = DRM_I915_PERF_RECORD_SAMPLE;
  header.pad = 0;
@@ -647,6 +649,23 @@ static int append_oa_sample(struct 
i915_perf_stream *stream,

    if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
  return -EFAULT;
+    buf += I915_PERF_TS_SAMPLE_SIZE;


This is a ridiculous nit, but I think using sizeof(u64) would be more 
readable than this I915_PERF_TS_SAMPLE_SIZE define.


Will update. Thanks.




+    }
+
+    if (sample_flags & SAMPLE_SYSTEM_TS) {
+    gpu_ts = get_gpu_ts_from_oa_report(stream, report);
+    /*
+ * XXX: timecounter_cyc2time considers time backwards if delta
+ * timestamp is more than half the max ns time covered by
+ * counter. It will be ~35min for 36 bit counter. If this much
+ * sampling duration is needed we will have to update tc->nsec
+ * by explicitly reading the timecounter (timecounter_read)
+ * before this duration.
+ */
+    system_ts = timecounter_cyc2time(>tc, gpu_ts);
+
+    if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
+    return -EFAULT;
  }
    (*offset) += header.size;
@@ -2137,6 +2156,11 @@ static int i915_oa_stream_init(struct 
i915_perf_stream *stream,

  stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
  }
  +    if (props->sample_flags & SAMPLE_SYSTEM_TS) {
+    stream->sample_flags |= SAMPLE_SYSTEM_TS;
+    stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
+    }
+
  dev_priv->perf.oa.oa_buffer.format_size = format_size;
  if (WARN_ON(dev_priv->perf.oa.oa_buffer.format_size == 0))
  return -EINVAL;
@@ -2857,6 +2881,9 @@ static int read_properties_unlocked(struct 
drm_i915_private *dev_priv,

  case DRM_I915_PERF_PROP_SAMPLE_GPU_TS:
  props->sample_flags |= SAMPLE_GPU_TS;
  break;
+    case DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS:
+    props->sample_flags |= SAMPLE_SYSTEM_TS;
+    break;
  case DRM_I915_PERF_PROP_OA_METRICS_SET:
  if (value == 0) {
  DRM_DEBUG("Unknown OA metric set ID\n");
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 0b9249e..283859c 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1453,6 +1453,12 @@ enum drm_i915_perf_property_id {
  DRM_I915_PERF_PROP_SAMPLE_GPU_TS,
    /**
+ * This property requests inclusion of CLOCK_MONOTONIC system 
time in

+ * the perf sample data.
+ */
+    DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS,
+
+    /**
   * The value specifies which set of OA unit metrics should be
   * be configured, defining the contents of any OA unit reports.
   */
@@ -1539,6 +1545,7 @@ enum drm_i915_perf_record_type {
   *
  

Re: [Intel-gfx] [RFC 4/4] drm/i915/perf: Send system clock monotonic time in perf samples

[Lionel Landwerlin]

On 15/11/17 12:13, Sagar Arun Kamble wrote:

From: Sourab Gupta 

Currently, we have the ability to only forward the GPU timestamps in the
samples (which are generated via OA reports). This limits the ability to
correlate these samples with the system events.

An ability is therefore needed to report timestamps in different clock
domains, such as CLOCK_MONOTONIC, in the perf samples to be of more
practical use to the userspace. This ability becomes important
when we want to correlate/plot GPU events/samples with other system events
on the same timeline (e.g. vblank events, or timestamps when work was
submitted to kernel, etc.)

The patch here proposes a mechanism to achieve this. The correlation
between gpu time and system time is established using the timestamp clock
associated with the command stream, abstracted as timecounter/cyclecounter
to retrieve gpu/system time correlated values.

v2: Added i915_driver_init_late() function to capture the new late init
phase for perf (Chris)

v3: Removed cross-timestamp changes.

Signed-off-by: Sourab Gupta 
Signed-off-by: Sagar Arun Kamble 
Cc: Lionel Landwerlin 
Cc: Chris Wilson 
Cc: Sourab Gupta 
Cc: Matthew Auld 
---
  drivers/gpu/drm/i915/i915_perf.c | 27 +++
  include/uapi/drm/i915_drm.h  |  7 +++
  2 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 3b721d7..94ee924 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -336,6 +336,7 @@
  
  #define SAMPLE_OA_REPORT	BIT(0)

  #define SAMPLE_GPU_TS BIT(1)
+#define SAMPLE_SYSTEM_TS   BIT(2)
  
  /**

   * struct perf_open_properties - for validated properties given to open a 
stream
@@ -622,6 +623,7 @@ static int append_oa_sample(struct i915_perf_stream *stream,
struct drm_i915_perf_record_header header;
u32 sample_flags = stream->sample_flags;
u64 gpu_ts = 0;
+   u64 system_ts = 0;
  
  	header.type = DRM_I915_PERF_RECORD_SAMPLE;

header.pad = 0;
@@ -647,6 +649,23 @@ static int append_oa_sample(struct i915_perf_stream 
*stream,
  
  		if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))

return -EFAULT;
+   buf += I915_PERF_TS_SAMPLE_SIZE;


This is a ridiculous nit, but I think using sizeof(u64) would be more 
readable than this I915_PERF_TS_SAMPLE_SIZE define.



+   }
+
+   if (sample_flags & SAMPLE_SYSTEM_TS) {
+   gpu_ts = get_gpu_ts_from_oa_report(stream, report);
+   /*
+* XXX: timecounter_cyc2time considers time backwards if delta
+* timestamp is more than half the max ns time covered by
+* counter. It will be ~35min for 36 bit counter. If this much
+* sampling duration is needed we will have to update tc->nsec
+* by explicitly reading the timecounter (timecounter_read)
+* before this duration.
+*/
+   system_ts = timecounter_cyc2time(>tc, gpu_ts);
+
+   if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
+   return -EFAULT;
}
  
  	(*offset) += header.size;

@@ -2137,6 +2156,11 @@ static int i915_oa_stream_init(struct i915_perf_stream 
*stream,
stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
}
  
+	if (props->sample_flags & SAMPLE_SYSTEM_TS) {

+   stream->sample_flags |= SAMPLE_SYSTEM_TS;
+   stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
+   }
+
dev_priv->perf.oa.oa_buffer.format_size = format_size;
if (WARN_ON(dev_priv->perf.oa.oa_buffer.format_size == 0))
return -EINVAL;
@@ -2857,6 +2881,9 @@ static int read_properties_unlocked(struct 
drm_i915_private *dev_priv,
case DRM_I915_PERF_PROP_SAMPLE_GPU_TS:
props->sample_flags |= SAMPLE_GPU_TS;
break;
+   case DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS:
+   props->sample_flags |= SAMPLE_SYSTEM_TS;
+   break;
case DRM_I915_PERF_PROP_OA_METRICS_SET:
if (value == 0) {
DRM_DEBUG("Unknown OA metric set ID\n");
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 0b9249e..283859c 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1453,6 +1453,12 @@ enum drm_i915_perf_property_id {
DRM_I915_PERF_PROP_SAMPLE_GPU_TS,
  
  	/**

+* This property requests inclusion of CLOCK_MONOTONIC system time in
+* the perf sample data.
+*/
+   DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS,
+
+   /**
 * The value specifies which set of OA 

Re: [Intel-gfx] [RFC 4/4] drm/i915/perf: Send system clock monotonic time in perf samples

[Sagar Arun Kamble]

On 11/15/2017 6:01 PM, Chris Wilson wrote:

Quoting Sagar Arun Kamble (2017-11-15 12:13:54)

From: Sourab Gupta 

Currently, we have the ability to only forward the GPU timestamps in the
samples (which are generated via OA reports). This limits the ability to
correlate these samples with the system events.

An ability is therefore needed to report timestamps in different clock
domains, such as CLOCK_MONOTONIC, in the perf samples to be of more
practical use to the userspace. This ability becomes important
when we want to correlate/plot GPU events/samples with other system events
on the same timeline (e.g. vblank events, or timestamps when work was
submitted to kernel, etc.)

The patch here proposes a mechanism to achieve this. The correlation
between gpu time and system time is established using the timestamp clock
associated with the command stream, abstracted as timecounter/cyclecounter
to retrieve gpu/system time correlated values.

v2: Added i915_driver_init_late() function to capture the new late init
phase for perf (Chris)

v3: Removed cross-timestamp changes.

Signed-off-by: Sourab Gupta 
Signed-off-by: Sagar Arun Kamble 
Cc: Lionel Landwerlin 
Cc: Chris Wilson 
Cc: Sourab Gupta 
Cc: Matthew Auld 
---
  drivers/gpu/drm/i915/i915_perf.c | 27 +++
  include/uapi/drm/i915_drm.h  |  7 +++
  2 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 3b721d7..94ee924 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -336,6 +336,7 @@
  
  #define SAMPLE_OA_REPORT   BIT(0)

  #define SAMPLE_GPU_TS  BIT(1)
+#define SAMPLE_SYSTEM_TS   BIT(2)
  
  /**

   * struct perf_open_properties - for validated properties given to open a 
stream
@@ -622,6 +623,7 @@ static int append_oa_sample(struct i915_perf_stream *stream,
 struct drm_i915_perf_record_header header;
 u32 sample_flags = stream->sample_flags;
 u64 gpu_ts = 0;
+   u64 system_ts = 0;
  
 header.type = DRM_I915_PERF_RECORD_SAMPLE;

 header.pad = 0;
@@ -647,6 +649,23 @@ static int append_oa_sample(struct i915_perf_stream 
*stream,
  
 if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))

 return -EFAULT;
+   buf += I915_PERF_TS_SAMPLE_SIZE;
+   }
+
+   if (sample_flags & SAMPLE_SYSTEM_TS) {
+   gpu_ts = get_gpu_ts_from_oa_report(stream, report);

Scope your variables. Stops us from being confused as to where else
gpu_ts or sys_ts may be reused. For instance I first thought you were
using SAMPLE_GPU_TS to initialise gpu_ts

Yes

+   /*
+* XXX: timecounter_cyc2time considers time backwards if delta
+* timestamp is more than half the max ns time covered by
+* counter. It will be ~35min for 36 bit counter. If this much
+* sampling duration is needed we will have to update tc->nsec
+* by explicitly reading the timecounter (timecounter_read)
+* before this duration.
+*/
+   system_ts = timecounter_cyc2time(>tc, gpu_ts);
+
+   if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
+   return -EFAULT;

Advance buf.
Had kept advance logic only if there is new field to be added as this 
advance is missing for

SAMPLE_OA_REPORT currently in drm-tip. Will fix.
Thanks for the review :)

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Re: [Intel-gfx] [RFC 4/4] drm/i915/perf: Send system clock monotonic time in perf samples

[Sagar Arun Kamble]

On 11/15/2017 5:43 PM, Sagar Arun Kamble wrote:

From: Sourab Gupta 

Currently, we have the ability to only forward the GPU timestamps in the
samples (which are generated via OA reports). This limits the ability to
correlate these samples with the system events.

An ability is therefore needed to report timestamps in different clock
domains, such as CLOCK_MONOTONIC, in the perf samples to be of more
practical use to the userspace. This ability becomes important
when we want to correlate/plot GPU events/samples with other system events
on the same timeline (e.g. vblank events, or timestamps when work was
submitted to kernel, etc.)

The patch here proposes a mechanism to achieve this. The correlation
between gpu time and system time is established using the timestamp clock
associated with the command stream, abstracted as timecounter/cyclecounter
to retrieve gpu/system time correlated values.

v2: Added i915_driver_init_late() function to capture the new late init
phase for perf (Chris)

v3: Removed cross-timestamp changes.

Signed-off-by: Sourab Gupta 
Signed-off-by: Sagar Arun Kamble 
Cc: Lionel Landwerlin 
Cc: Chris Wilson 
Cc: Sourab Gupta 
Cc: Matthew Auld 
---
  drivers/gpu/drm/i915/i915_perf.c | 27 +++
  include/uapi/drm/i915_drm.h  |  7 +++
  2 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 3b721d7..94ee924 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -336,6 +336,7 @@
  
  #define SAMPLE_OA_REPORT	BIT(0)

  #define SAMPLE_GPU_TS BIT(1)
+#define SAMPLE_SYSTEM_TS   BIT(2)
  
  /**

   * struct perf_open_properties - for validated properties given to open a 
stream
@@ -622,6 +623,7 @@ static int append_oa_sample(struct i915_perf_stream *stream,
struct drm_i915_perf_record_header header;
u32 sample_flags = stream->sample_flags;
u64 gpu_ts = 0;
+   u64 system_ts = 0;
  
  	header.type = DRM_I915_PERF_RECORD_SAMPLE;

header.pad = 0;
@@ -647,6 +649,23 @@ static int append_oa_sample(struct i915_perf_stream 
*stream,
  
  		if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))

return -EFAULT;
+   buf += I915_PERF_TS_SAMPLE_SIZE;
+   }
+
+   if (sample_flags & SAMPLE_SYSTEM_TS) {
+   gpu_ts = get_gpu_ts_from_oa_report(stream, report);
+   /*
+* XXX: timecounter_cyc2time considers time backwards if delta
+* timestamp is more than half the max ns time covered by
+* counter. It will be ~35min for 36 bit counter. If this much
+* sampling duration is needed we will have to update tc->nsec
+* by explicitly reading the timecounter (timecounter_read)
+* before this duration.
This is implemented as overflow watchdog in mlx5e_timestamp_init 
(drivers/net/ethernet/mellanox).

Will need similar mechanism here.

+*/
+   system_ts = timecounter_cyc2time(>tc, gpu_ts);
+
+   if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
+   return -EFAULT;
}
  
  	(*offset) += header.size;

@@ -2137,6 +2156,11 @@ static int i915_oa_stream_init(struct i915_perf_stream 
*stream,
stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
}
  
+	if (props->sample_flags & SAMPLE_SYSTEM_TS) {

+   stream->sample_flags |= SAMPLE_SYSTEM_TS;
+   stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
+   }
+
dev_priv->perf.oa.oa_buffer.format_size = format_size;
if (WARN_ON(dev_priv->perf.oa.oa_buffer.format_size == 0))
return -EINVAL;
@@ -2857,6 +2881,9 @@ static int read_properties_unlocked(struct 
drm_i915_private *dev_priv,
case DRM_I915_PERF_PROP_SAMPLE_GPU_TS:
props->sample_flags |= SAMPLE_GPU_TS;
break;
+   case DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS:
+   props->sample_flags |= SAMPLE_SYSTEM_TS;
+   break;
case DRM_I915_PERF_PROP_OA_METRICS_SET:
if (value == 0) {
DRM_DEBUG("Unknown OA metric set ID\n");
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 0b9249e..283859c 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1453,6 +1453,12 @@ enum drm_i915_perf_property_id {
DRM_I915_PERF_PROP_SAMPLE_GPU_TS,
  
  	/**

+* This property requests inclusion of CLOCK_MONOTONIC system time in
+* the perf sample data.
+*/
+   DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS,
+
+   /**
 * The value specifies 

Re: [Intel-gfx] [RFC 4/4] drm/i915/perf: Send system clock monotonic time in perf samples

[Chris Wilson]

Quoting Sagar Arun Kamble (2017-11-15 12:13:54)
> From: Sourab Gupta 
> 
> Currently, we have the ability to only forward the GPU timestamps in the
> samples (which are generated via OA reports). This limits the ability to
> correlate these samples with the system events.
> 
> An ability is therefore needed to report timestamps in different clock
> domains, such as CLOCK_MONOTONIC, in the perf samples to be of more
> practical use to the userspace. This ability becomes important
> when we want to correlate/plot GPU events/samples with other system events
> on the same timeline (e.g. vblank events, or timestamps when work was
> submitted to kernel, etc.)
> 
> The patch here proposes a mechanism to achieve this. The correlation
> between gpu time and system time is established using the timestamp clock
> associated with the command stream, abstracted as timecounter/cyclecounter
> to retrieve gpu/system time correlated values.
> 
> v2: Added i915_driver_init_late() function to capture the new late init
> phase for perf (Chris)
> 
> v3: Removed cross-timestamp changes.
> 
> Signed-off-by: Sourab Gupta 
> Signed-off-by: Sagar Arun Kamble 
> Cc: Lionel Landwerlin 
> Cc: Chris Wilson 
> Cc: Sourab Gupta 
> Cc: Matthew Auld 
> ---
>  drivers/gpu/drm/i915/i915_perf.c | 27 +++
>  include/uapi/drm/i915_drm.h  |  7 +++
>  2 files changed, 34 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_perf.c 
> b/drivers/gpu/drm/i915/i915_perf.c
> index 3b721d7..94ee924 100644
> --- a/drivers/gpu/drm/i915/i915_perf.c
> +++ b/drivers/gpu/drm/i915/i915_perf.c
> @@ -336,6 +336,7 @@
>  
>  #define SAMPLE_OA_REPORT   BIT(0)
>  #define SAMPLE_GPU_TS  BIT(1)
> +#define SAMPLE_SYSTEM_TS   BIT(2)
>  
>  /**
>   * struct perf_open_properties - for validated properties given to open a 
> stream
> @@ -622,6 +623,7 @@ static int append_oa_sample(struct i915_perf_stream 
> *stream,
> struct drm_i915_perf_record_header header;
> u32 sample_flags = stream->sample_flags;
> u64 gpu_ts = 0;
> +   u64 system_ts = 0;
>  
> header.type = DRM_I915_PERF_RECORD_SAMPLE;
> header.pad = 0;
> @@ -647,6 +649,23 @@ static int append_oa_sample(struct i915_perf_stream 
> *stream,
>  
> if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
> return -EFAULT;
> +   buf += I915_PERF_TS_SAMPLE_SIZE;
> +   }
> +
> +   if (sample_flags & SAMPLE_SYSTEM_TS) {
> +   gpu_ts = get_gpu_ts_from_oa_report(stream, report);

Scope your variables. Stops us from being confused as to where else
gpu_ts or sys_ts may be reused. For instance I first thought you were
using SAMPLE_GPU_TS to initialise gpu_ts

> +   /*
> +* XXX: timecounter_cyc2time considers time backwards if delta
> +* timestamp is more than half the max ns time covered by
> +* counter. It will be ~35min for 36 bit counter. If this much
> +* sampling duration is needed we will have to update tc->nsec
> +* by explicitly reading the timecounter (timecounter_read)
> +* before this duration.
> +*/
> +   system_ts = timecounter_cyc2time(>tc, gpu_ts);
> +
> +   if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
> +   return -EFAULT;

Advance buf.
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[Intel-gfx] [RFC 4/4] drm/i915/perf: Send system clock monotonic time in perf samples

[Sagar Arun Kamble]

From: Sourab Gupta 

Currently, we have the ability to only forward the GPU timestamps in the
samples (which are generated via OA reports). This limits the ability to
correlate these samples with the system events.

An ability is therefore needed to report timestamps in different clock
domains, such as CLOCK_MONOTONIC, in the perf samples to be of more
practical use to the userspace. This ability becomes important
when we want to correlate/plot GPU events/samples with other system events
on the same timeline (e.g. vblank events, or timestamps when work was
submitted to kernel, etc.)

The patch here proposes a mechanism to achieve this. The correlation
between gpu time and system time is established using the timestamp clock
associated with the command stream, abstracted as timecounter/cyclecounter
to retrieve gpu/system time correlated values.

v2: Added i915_driver_init_late() function to capture the new late init
phase for perf (Chris)

v3: Removed cross-timestamp changes.

Signed-off-by: Sourab Gupta 
Signed-off-by: Sagar Arun Kamble 
Cc: Lionel Landwerlin 
Cc: Chris Wilson 
Cc: Sourab Gupta 
Cc: Matthew Auld 
---
 drivers/gpu/drm/i915/i915_perf.c | 27 +++
 include/uapi/drm/i915_drm.h  |  7 +++
 2 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 3b721d7..94ee924 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -336,6 +336,7 @@
 
 #define SAMPLE_OA_REPORT   BIT(0)
 #define SAMPLE_GPU_TS  BIT(1)
+#define SAMPLE_SYSTEM_TS   BIT(2)
 
 /**
  * struct perf_open_properties - for validated properties given to open a 
stream
@@ -622,6 +623,7 @@ static int append_oa_sample(struct i915_perf_stream *stream,
struct drm_i915_perf_record_header header;
u32 sample_flags = stream->sample_flags;
u64 gpu_ts = 0;
+   u64 system_ts = 0;
 
header.type = DRM_I915_PERF_RECORD_SAMPLE;
header.pad = 0;
@@ -647,6 +649,23 @@ static int append_oa_sample(struct i915_perf_stream 
*stream,
 
if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
return -EFAULT;
+   buf += I915_PERF_TS_SAMPLE_SIZE;
+   }
+
+   if (sample_flags & SAMPLE_SYSTEM_TS) {
+   gpu_ts = get_gpu_ts_from_oa_report(stream, report);
+   /*
+* XXX: timecounter_cyc2time considers time backwards if delta
+* timestamp is more than half the max ns time covered by
+* counter. It will be ~35min for 36 bit counter. If this much
+* sampling duration is needed we will have to update tc->nsec
+* by explicitly reading the timecounter (timecounter_read)
+* before this duration.
+*/
+   system_ts = timecounter_cyc2time(>tc, gpu_ts);
+
+   if (copy_to_user(buf, _ts, I915_PERF_TS_SAMPLE_SIZE))
+   return -EFAULT;
}
 
(*offset) += header.size;
@@ -2137,6 +2156,11 @@ static int i915_oa_stream_init(struct i915_perf_stream 
*stream,
stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
}
 
+   if (props->sample_flags & SAMPLE_SYSTEM_TS) {
+   stream->sample_flags |= SAMPLE_SYSTEM_TS;
+   stream->sample_size += I915_PERF_TS_SAMPLE_SIZE;
+   }
+
dev_priv->perf.oa.oa_buffer.format_size = format_size;
if (WARN_ON(dev_priv->perf.oa.oa_buffer.format_size == 0))
return -EINVAL;
@@ -2857,6 +2881,9 @@ static int read_properties_unlocked(struct 
drm_i915_private *dev_priv,
case DRM_I915_PERF_PROP_SAMPLE_GPU_TS:
props->sample_flags |= SAMPLE_GPU_TS;
break;
+   case DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS:
+   props->sample_flags |= SAMPLE_SYSTEM_TS;
+   break;
case DRM_I915_PERF_PROP_OA_METRICS_SET:
if (value == 0) {
DRM_DEBUG("Unknown OA metric set ID\n");
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 0b9249e..283859c 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1453,6 +1453,12 @@ enum drm_i915_perf_property_id {
DRM_I915_PERF_PROP_SAMPLE_GPU_TS,
 
/**
+* This property requests inclusion of CLOCK_MONOTONIC system time in
+* the perf sample data.
+*/
+   DRM_I915_PERF_PROP_SAMPLE_SYSTEM_TS,
+
+   /**
 * The value specifies which set of OA unit metrics should be
 * be configured, defining the contents of any OA unit reports.
 */
@@ -1539,6 +1545,7 @@ enum