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* [PATCH] drm/xe: improve Kconfig.profile help text for scheduler timeouts
@ 2026-06-05 14:09 Rodrigo Vivi
  2026-06-05 15:32 ` ✓ CI.KUnit: success for drm/xe: improve Kconfig.profile help text for scheduler timeouts (rev2) Patchwork
                   ` (3 more replies)
  0 siblings, 4 replies; 7+ messages in thread
From: Rodrigo Vivi @ 2026-06-05 14:09 UTC (permalink / raw)
  To: intel-xe; +Cc: Rodrigo Vivi, Paulo Zanoni

The existing help texts for the JOB_TIMEOUT, TIMESLICE and PREEMPT_TIMEOUT
configs were brief and did not make the role of each symbol clear:

 - _MIN / _MAX: hard bounds on the per-engine-class timeout. They are
                enforced unconditionally by the sysfs knobs, and (for
                TIMESLICE, the only one exposed via the SET_PROPERTY UAPI)
                they also bound CAP_SYS_NICE requests when
                DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT is enabled.
 - PREEMPT_TIMEOUT: the boot-time default; the JOB_TIMEOUT and TIMESLICE
                    defaults are hardcoded in the driver, not configured
                    here.

Rewrite the help texts to reflect this, naming the relevant sysfs knobs
and UAPI property explicitly.

v2: Adjusted commit message based on Sashiko's review.

Assisted-by: GitHub-Copilot:claude-sonnet-4.6
Assisted-by: GitHub-Copilot:claude-opus-4.8 #v2
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
---
 drivers/gpu/drm/xe/Kconfig.profile | 71 +++++++++++++++++++-----------
 1 file changed, 46 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/xe/Kconfig.profile b/drivers/gpu/drm/xe/Kconfig.profile
index 7530df998148..e07517d120e0 100644
--- a/drivers/gpu/drm/xe/Kconfig.profile
+++ b/drivers/gpu/drm/xe/Kconfig.profile
@@ -1,50 +1,71 @@
 # SPDX-License-Identifier: GPL-2.0-only
 config DRM_XE_JOB_TIMEOUT_MAX
-	int "Default max job timeout (ms)"
+	int "Hard upper limit for job timeout (ms)"
 	default 10000 # milliseconds
 	help
-	  Configures the default max job timeout after which job will
-	  be forcefully taken away from scheduler.
+	  Absolute upper bound (in milliseconds) for the per-engine-class job
+	  timeout. This is the maximum value that can be written to the sysfs
+	  job_timeout_ms knob, regardless of privileges. To raise this ceiling,
+	  increase this value and rebuild the kernel.
 config DRM_XE_JOB_TIMEOUT_MIN
-	int "Default min job timeout (ms)"
+	int "Hard lower limit for job timeout (ms)"
 	default 1 # milliseconds
 	help
-	  Configures the default min job timeout after which job will
-	  be forcefully taken away from scheduler.
+	  Absolute lower bound (in milliseconds) for the per-engine-class job
+	  timeout. This is the minimum value that can be written to the sysfs
+	  job_timeout_ms knob, regardless of privileges.
+
+	  Note: the job timeout default (5000 ms) is hardcoded in the driver
+	  and is not configurable here. Use the sysfs job_timeout_ms knob at
+	  runtime to change the engine-class default.
 config DRM_XE_TIMESLICE_MAX
-	int "Default max timeslice duration (us)"
+	int "Hard upper limit for timeslice duration (us)"
 	default 10000000 # microseconds
 	help
-	  Configures the default max timeslice duration between multiple
-	  contexts by guc scheduling.
+	  Absolute upper bound (in microseconds) for the timeslice duration.
+	  This caps both the sysfs timeslice_duration_us knob and the value
+	  accepted via the DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE UAPI for
+	  processes with CAP_SYS_NICE when DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT
+	  is enabled.
 config DRM_XE_TIMESLICE_MIN
-	int "Default min timeslice duration (us)"
+	int "Hard lower limit for timeslice duration (us)"
 	default 1 # microseconds
 	help
-	  Configures the default min timeslice duration between multiple
-	  contexts by guc scheduling.
+	  Absolute lower bound (in microseconds) for the timeslice duration.
+	  This caps both the sysfs timeslice_duration_us knob and the value
+	  accepted via the DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE UAPI for
+	  processes with CAP_SYS_NICE when DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT
+	  is enabled.
 config DRM_XE_PREEMPT_TIMEOUT
-	int "Preempt timeout (us, jiffy granularity)"
+	int "Default preempt timeout (us, jiffy granularity)"
 	default 640000 # microseconds
 	help
-	  How long to wait (in microseconds) for a preemption event to occur
-	  when submitting a new context. If the current context does not hit
-	  an arbitration point and yield to HW before the timer expires, the
-	  HW will be reset to allow the more important context to execute.
+	  Initial per-engine-class preemption timeout (in microseconds). This
+	  is the value the driver programs at boot; it can be changed at
+	  runtime via the sysfs preempt_timeout_us knob.
+
+	  This is how long the driver waits for the current context to reach
+	  an arbitration point and yield the GPU voluntarily when a
+	  higher-priority context becomes runnable. If the context does not
+	  yield before the timer expires, the HW is reset to allow the
+	  higher-priority context to execute.
+
+	  The range userspace may write via sysfs is bounded by
+	  DRM_XE_PREEMPT_TIMEOUT_MIN and DRM_XE_PREEMPT_TIMEOUT_MAX.
 config DRM_XE_PREEMPT_TIMEOUT_MAX
-	int "Default max preempt timeout (us)"
+	int "Hard upper limit for preempt timeout (us)"
 	default 10000000 # microseconds
 	help
-	  Configures the default max preempt timeout after which context
-	  will be forcefully taken away and higher priority context will
-	  run.
+	  Absolute upper bound (in microseconds) for the per-engine-class
+	  preemption timeout. This is the maximum value that can be written to
+	  the sysfs preempt_timeout_us knob, regardless of privileges.
 config DRM_XE_PREEMPT_TIMEOUT_MIN
-	int "Default min preempt timeout (us)"
+	int "Hard lower limit for preempt timeout (us)"
 	default 1 # microseconds
 	help
-	  Configures the default min preempt timeout after which context
-	  will be forcefully taken away and higher priority context will
-	  run.
+	  Absolute lower bound (in microseconds) for the per-engine-class
+	  preemption timeout. This is the minimum value that can be written to
+	  the sysfs preempt_timeout_us knob, regardless of privileges.
 config DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT
 	bool "Default configuration of limitation on scheduler timeout"
 	default y
-- 
2.54.0


^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [PATCH] drm/xe: improve Kconfig.profile help text for scheduler timeouts
@ 2026-05-28 20:24 Rodrigo Vivi
  2026-06-04 20:57 ` Zanoni, Paulo R
  0 siblings, 1 reply; 7+ messages in thread
From: Rodrigo Vivi @ 2026-05-28 20:24 UTC (permalink / raw)
  To: intel-xe; +Cc: Rodrigo Vivi, Paulo Zanoni

The existing help texts for JOB_TIMEOUT, TIMESLICE and PREEMPT_TIMEOUT
configs were brief and did not make clear the role each symbol plays:

 - _TIMEOUT  : the kernel default, used when no userspace application
               overrides it via the SET_PROPERTY UAPI.
 - _TIMEOUT_MIN: lower bound of the range accepted by the UAPI; requests
                 below this value are rejected.
 - _TIMEOUT_MAX: upper bound of the range accepted by the UAPI; requests
                 above this value are rejected.

Rewrite the help texts to reflect this distinction, name the relevant
UAPI properties explicitly, and clarify that the MIN/MAX limits are only
enforced when DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT is enabled.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Assisted-by: GitHub-Copilot:claude-sonnet-4.6
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
---
 drivers/gpu/drm/xe/Kconfig.profile | 71 +++++++++++++++++++-----------
 1 file changed, 46 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/xe/Kconfig.profile b/drivers/gpu/drm/xe/Kconfig.profile
index 7530df998148..e07517d120e0 100644
--- a/drivers/gpu/drm/xe/Kconfig.profile
+++ b/drivers/gpu/drm/xe/Kconfig.profile
@@ -1,50 +1,71 @@
 # SPDX-License-Identifier: GPL-2.0-only
 config DRM_XE_JOB_TIMEOUT_MAX
-	int "Default max job timeout (ms)"
+	int "Hard upper limit for job timeout (ms)"
 	default 10000 # milliseconds
 	help
-	  Configures the default max job timeout after which job will
-	  be forcefully taken away from scheduler.
+	  Absolute upper bound (in milliseconds) for the per-engine-class job
+	  timeout. This is the maximum value that can be written to the sysfs
+	  job_timeout_ms knob, regardless of privileges. To raise this ceiling,
+	  increase this value and rebuild the kernel.
 config DRM_XE_JOB_TIMEOUT_MIN
-	int "Default min job timeout (ms)"
+	int "Hard lower limit for job timeout (ms)"
 	default 1 # milliseconds
 	help
-	  Configures the default min job timeout after which job will
-	  be forcefully taken away from scheduler.
+	  Absolute lower bound (in milliseconds) for the per-engine-class job
+	  timeout. This is the minimum value that can be written to the sysfs
+	  job_timeout_ms knob, regardless of privileges.
+
+	  Note: the job timeout default (5000 ms) is hardcoded in the driver
+	  and is not configurable here. Use the sysfs job_timeout_ms knob at
+	  runtime to change the engine-class default.
 config DRM_XE_TIMESLICE_MAX
-	int "Default max timeslice duration (us)"
+	int "Hard upper limit for timeslice duration (us)"
 	default 10000000 # microseconds
 	help
-	  Configures the default max timeslice duration between multiple
-	  contexts by guc scheduling.
+	  Absolute upper bound (in microseconds) for the timeslice duration.
+	  This caps both the sysfs timeslice_duration_us knob and the value
+	  accepted via the DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE UAPI for
+	  processes with CAP_SYS_NICE when DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT
+	  is enabled.
 config DRM_XE_TIMESLICE_MIN
-	int "Default min timeslice duration (us)"
+	int "Hard lower limit for timeslice duration (us)"
 	default 1 # microseconds
 	help
-	  Configures the default min timeslice duration between multiple
-	  contexts by guc scheduling.
+	  Absolute lower bound (in microseconds) for the timeslice duration.
+	  This caps both the sysfs timeslice_duration_us knob and the value
+	  accepted via the DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE UAPI for
+	  processes with CAP_SYS_NICE when DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT
+	  is enabled.
 config DRM_XE_PREEMPT_TIMEOUT
-	int "Preempt timeout (us, jiffy granularity)"
+	int "Default preempt timeout (us, jiffy granularity)"
 	default 640000 # microseconds
 	help
-	  How long to wait (in microseconds) for a preemption event to occur
-	  when submitting a new context. If the current context does not hit
-	  an arbitration point and yield to HW before the timer expires, the
-	  HW will be reset to allow the more important context to execute.
+	  Initial per-engine-class preemption timeout (in microseconds). This
+	  is the value the driver programs at boot; it can be changed at
+	  runtime via the sysfs preempt_timeout_us knob.
+
+	  This is how long the driver waits for the current context to reach
+	  an arbitration point and yield the GPU voluntarily when a
+	  higher-priority context becomes runnable. If the context does not
+	  yield before the timer expires, the HW is reset to allow the
+	  higher-priority context to execute.
+
+	  The range userspace may write via sysfs is bounded by
+	  DRM_XE_PREEMPT_TIMEOUT_MIN and DRM_XE_PREEMPT_TIMEOUT_MAX.
 config DRM_XE_PREEMPT_TIMEOUT_MAX
-	int "Default max preempt timeout (us)"
+	int "Hard upper limit for preempt timeout (us)"
 	default 10000000 # microseconds
 	help
-	  Configures the default max preempt timeout after which context
-	  will be forcefully taken away and higher priority context will
-	  run.
+	  Absolute upper bound (in microseconds) for the per-engine-class
+	  preemption timeout. This is the maximum value that can be written to
+	  the sysfs preempt_timeout_us knob, regardless of privileges.
 config DRM_XE_PREEMPT_TIMEOUT_MIN
-	int "Default min preempt timeout (us)"
+	int "Hard lower limit for preempt timeout (us)"
 	default 1 # microseconds
 	help
-	  Configures the default min preempt timeout after which context
-	  will be forcefully taken away and higher priority context will
-	  run.
+	  Absolute lower bound (in microseconds) for the per-engine-class
+	  preemption timeout. This is the minimum value that can be written to
+	  the sysfs preempt_timeout_us knob, regardless of privileges.
 config DRM_XE_ENABLE_SCHEDTIMEOUT_LIMIT
 	bool "Default configuration of limitation on scheduler timeout"
 	default y
-- 
2.54.0


^ permalink raw reply related	[flat|nested] 7+ messages in thread
end of thread, other threads:[~2026-06-06  4:11 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
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2026-06-05 14:09 [PATCH] drm/xe: improve Kconfig.profile help text for scheduler timeouts Rodrigo Vivi
2026-06-05 15:32 ` ✓ CI.KUnit: success for drm/xe: improve Kconfig.profile help text for scheduler timeouts (rev2) Patchwork
2026-06-05 16:20 ` ✓ Xe.CI.BAT: " Patchwork
2026-06-05 16:48 ` [PATCH] drm/xe: improve Kconfig.profile help text for scheduler timeouts Rodrigo Vivi
2026-06-06  4:11 ` ✓ Xe.CI.FULL: success for drm/xe: improve Kconfig.profile help text for scheduler timeouts (rev2) Patchwork
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2026-05-28 20:24 [PATCH] drm/xe: improve Kconfig.profile help text for scheduler timeouts Rodrigo Vivi
2026-06-04 20:57 ` Zanoni, Paulo R

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