All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org
Cc: Jani Nikula <jani.nikula@linux.intel.com>,
	Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@intel.com>,
	David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
	Thomas Gleixner <tglx@linutronix.de>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Subject: [PATCH 7/8] drm/i915: Drop the irqs_disabled() check
Date: Tue,  5 Oct 2021 17:00:45 +0200	[thread overview]
Message-ID: <20211005150046.1000285-8-bigeasy@linutronix.de> (raw)
In-Reply-To: <20211005150046.1000285-1-bigeasy@linutronix.de>

The !irqs_disabled() check triggers on PREEMPT_RT even with
i915_sched_engine::lock acquired. The reason is the lock is transformed
into a sleeping lock on PREEMPT_RT and does not disable interrupts.

There is no need to check for disabled interrupts. The lockdep
annotation below already check if the lock has been acquired by the
caller and will yell if the interrupts are not disabled.

Remove the !irqs_disabled() check.

Reported-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 drivers/gpu/drm/i915/i915_request.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 79da5eca60af5..b9dd6100c6d17 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -559,7 +559,6 @@ bool __i915_request_submit(struct i915_request *request)
 
 	RQ_TRACE(request, "\n");
 
-	GEM_BUG_ON(!irqs_disabled());
 	lockdep_assert_held(&engine->sched_engine->lock);
 
 	/*
@@ -668,7 +667,6 @@ void __i915_request_unsubmit(struct i915_request *request)
 	 */
 	RQ_TRACE(request, "\n");
 
-	GEM_BUG_ON(!irqs_disabled());
 	lockdep_assert_held(&engine->sched_engine->lock);
 
 	/*
-- 
2.33.0


WARNING: multiple messages have this Message-ID (diff)
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org
Cc: Jani Nikula <jani.nikula@linux.intel.com>,
	Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@intel.com>,
	David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
	Thomas Gleixner <tglx@linutronix.de>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Subject: [Intel-gfx] [PATCH 7/8] drm/i915: Drop the irqs_disabled() check
Date: Tue,  5 Oct 2021 17:00:45 +0200	[thread overview]
Message-ID: <20211005150046.1000285-8-bigeasy@linutronix.de> (raw)
In-Reply-To: <20211005150046.1000285-1-bigeasy@linutronix.de>

The !irqs_disabled() check triggers on PREEMPT_RT even with
i915_sched_engine::lock acquired. The reason is the lock is transformed
into a sleeping lock on PREEMPT_RT and does not disable interrupts.

There is no need to check for disabled interrupts. The lockdep
annotation below already check if the lock has been acquired by the
caller and will yell if the interrupts are not disabled.

Remove the !irqs_disabled() check.

Reported-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 drivers/gpu/drm/i915/i915_request.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 79da5eca60af5..b9dd6100c6d17 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -559,7 +559,6 @@ bool __i915_request_submit(struct i915_request *request)
 
 	RQ_TRACE(request, "\n");
 
-	GEM_BUG_ON(!irqs_disabled());
 	lockdep_assert_held(&engine->sched_engine->lock);
 
 	/*
@@ -668,7 +667,6 @@ void __i915_request_unsubmit(struct i915_request *request)
 	 */
 	RQ_TRACE(request, "\n");
 
-	GEM_BUG_ON(!irqs_disabled());
 	lockdep_assert_held(&engine->sched_engine->lock);
 
 	/*
-- 
2.33.0


  parent reply	other threads:[~2021-10-05 15:01 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-05 15:00 [PATCH 0/8] drm/i915: PREEMPT_RT related fixups Sebastian Andrzej Siewior
2021-10-05 15:00 ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 15:00 ` [PATCH 1/8] drm/i915: Use preempt_disable/enable_rt() where recommended Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 15:00 ` [PATCH 2/8] drm/i915: Don't disable interrupts on PREEMPT_RT during atomic updates Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-06  9:16   ` Ville Syrjälä
2021-10-05 15:00 ` [PATCH 3/8] drm/i915: Disable tracing points on PREEMPT_RT Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-06  9:34   ` Ville Syrjälä
2021-10-06  9:34     ` [Intel-gfx] " Ville Syrjälä
2021-10-06 10:15     ` Sebastian Andrzej Siewior
2021-10-06 10:15       ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-06 16:46       ` Sebastian Andrzej Siewior
2021-10-06 16:46         ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 15:00 ` [PATCH 4/8] drm/i915: skip DRM_I915_LOW_LEVEL_TRACEPOINTS with NOTRACE Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 15:00 ` [PATCH 5/8] drm/i915/gt: Queue and wait for the irq_work item Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 15:00 ` [PATCH 6/8] drm/i915/gt: Use spin_lock_irq() instead of local_irq_disable() + spin_lock() Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 15:00 ` Sebastian Andrzej Siewior [this message]
2021-10-05 15:00   ` [Intel-gfx] [PATCH 7/8] drm/i915: Drop the irqs_disabled() check Sebastian Andrzej Siewior
2021-10-05 15:00 ` [PATCH 8/8] drm/i915: Don't disable interrupts and pretend a lock as been acquired in __timeline_mark_lock() Sebastian Andrzej Siewior
2021-10-05 15:00   ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-05 19:16   ` Peter Zijlstra
2021-10-05 19:16     ` [Intel-gfx] " Peter Zijlstra
2021-10-06  6:58     ` Sebastian Andrzej Siewior
2021-10-06  6:58       ` [Intel-gfx] " Sebastian Andrzej Siewior
2021-10-08  6:21   ` [drm/i915] 511e5fb0c3: WARNING:suspicious_RCU_usage kernel test robot
2021-10-08  6:21     ` kernel test robot
2021-10-08  6:21     ` [Intel-gfx] " kernel test robot
2021-10-05 16:12 ` [Intel-gfx] ✗ Fi.CI.CHECKPATCH: warning for drm/i915: PREEMPT_RT related fixups Patchwork
2021-10-05 16:48 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
2021-10-06 17:41 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for drm/i915: PREEMPT_RT related fixups. (rev2) Patchwork

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211005150046.1000285-8-bigeasy@linutronix.de \
    --to=bigeasy@linutronix.de \
    --cc=airlied@linux.ie \
    --cc=daniel@ffwll.ch \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=jani.nikula@linux.intel.com \
    --cc=joonas.lahtinen@linux.intel.com \
    --cc=maarten.lankhorst@linux.intel.com \
    --cc=rodrigo.vivi@intel.com \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.