drm/i915/perf: Allow dynamic reconfiguration of the OA stream

Introduce a new perf_ioctl command to change the OA configuration of the
active stream. This allows the OA stream to be reconfigured between
batch buffers, giving greater flexibility in sampling. We inject a
request into the OA context to reconfigure the stream asynchronously on
the GPU in between and ordered with execbuffer calls.

Original patch for dynamic reconfiguration by Lionel Landwerlin.

Link: https://gitlab.freedesktop.org/mesa/mesa/merge_requests/932
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191014201404.22468-3-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2019-10-14 21:14:03 +01:00
parent 4f6ccc74a8
commit 7831e9a965
2 changed files with 58 additions and 1 deletions

View File

@ -2862,6 +2862,40 @@ static void i915_perf_disable_locked(struct i915_perf_stream *stream)
stream->ops->disable(stream);
}
static long i915_perf_config_locked(struct i915_perf_stream *stream,
unsigned long metrics_set)
{
struct i915_oa_config *config;
long ret = stream->oa_config->id;
config = i915_perf_get_oa_config(stream->perf, metrics_set);
if (!config)
return -EINVAL;
if (config != stream->oa_config) {
int err;
/*
* If OA is bound to a specific context, emit the
* reconfiguration inline from that context. The update
* will then be ordered with respect to submission on that
* context.
*
* When set globally, we use a low priority kernel context,
* so it will effectively take effect when idle.
*/
err = emit_oa_config(stream, oa_context(stream));
if (err == 0)
config = xchg(&stream->oa_config, config);
else
ret = err;
}
i915_oa_config_put(config);
return ret;
}
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@ -2885,6 +2919,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
case I915_PERF_IOCTL_DISABLE:
i915_perf_disable_locked(stream);
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
}
return -EINVAL;
@ -4023,7 +4059,15 @@ void i915_perf_fini(struct drm_i915_private *i915)
*/
int i915_perf_ioctl_version(void)
{
return 1;
/*
* 1: Initial version
* I915_PERF_IOCTL_ENABLE
* I915_PERF_IOCTL_DISABLE
*
* 2: Added runtime modification of OA config.
* I915_PERF_IOCTL_CONFIG
*/
return 2;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)

View File

@ -1932,6 +1932,19 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_DISABLE _IO('i', 0x1)
/**
* Change metrics_set captured by a stream.
*
* If the stream is bound to a specific context, the configuration change
* will performed inline with that context such that it takes effect before
* the next execbuf submission.
*
* Returns the previously bound metrics set id, or a negative error code.
*
* This ioctl is available in perf revision 2.
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
/**
* Common to all i915 perf records
*/