Commit 0b0120d4 authored by Lionel Landwerlin's avatar Lionel Landwerlin
Browse files

drm/i915/perf: always consider holding preemption a privileged op 



The ordering of the checks in the existing code can lead to holding
preemption not being considered as privileged op.

Signed-off-by: default avatarLionel Landwerlin <lionel.g.landwerlin@intel.com>
Fixes: 9cd20ef7 ("drm/i915/perf: allow holding preemption on filtered ctx")
Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191111095308.2550-1-lionel.g.landwerlin@intel.com
parent baea9ffe

drivers/gpu/drm/i915/i915_perf.c

+10 −10
Original line number Diff line number Diff line
@@ -3312,15 +3312,6 @@ i915_perf_open_ioctl_locked(struct i915_perf *perf, 
		}

	}



	if (props->hold_preemption) {

		if (!props->single_context) {

			DRM_DEBUG("preemption disable with no context\n");

			ret = -EINVAL;

			goto err;

		}

		privileged_op = true;

	}



	/*

	 * On Haswell the OA unit supports clock gating off for a specific

	 * context and in this mode there's no visibility of metrics for the
@@ -3340,12 +3331,21 @@ i915_perf_open_ioctl_locked(struct i915_perf *perf, 
	 * doesn't request global stream access (i.e. query based sampling

	 * using MI_RECORD_PERF_COUNT.

	 */

	if (IS_HASWELL(perf->i915) && specific_ctx && !props->hold_preemption)

	if (IS_HASWELL(perf->i915) && specific_ctx)

		privileged_op = false;

	else if (IS_GEN(perf->i915, 12) && specific_ctx &&

		 (props->sample_flags & SAMPLE_OA_REPORT) == 0)

		privileged_op = false;



	if (props->hold_preemption) {

		if (!props->single_context) {

			DRM_DEBUG("preemption disable with no context\n");

			ret = -EINVAL;

			goto err;

		}

		privileged_op = true;

	}



	/* Similar to perf's kernel.perf_paranoid_cpu sysctl option

	 * we check a dev.i915.perf_stream_paranoid sysctl option

	 * to determine if it's ok to access system wide OA counters

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