Intel-GFX Archive on lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] drm/i915: Make i915_gem_context_mark_guilty() safe for unlocked updates
@ 2017-07-09  9:35 Chris Wilson
  2017-07-09  9:53 ` ✓ Fi.CI.BAT: success for " Patchwork
  2017-07-10 14:14 ` [PATCH] " Mika Kuoppala
  0 siblings, 2 replies; 4+ messages in thread
From: Chris Wilson @ 2017-07-09  9:35 UTC (permalink / raw)
  To: intel-gfx

Since we make call i915_gem_context_mark_guilty() concurrently when
resetting different engines in parallel, we need to make sure that our
updates are safe for the unlocked access.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h         |  2 +-
 drivers/gpu/drm/i915/i915_gem.c         | 32 ++++++++++++++++++--------------
 drivers/gpu/drm/i915/i915_gem_context.c |  6 +++---
 drivers/gpu/drm/i915/i915_gem_context.h |  6 +++---
 drivers/gpu/drm/i915/i915_gem_request.c |  3 +--
 drivers/gpu/drm/i915/i915_gpu_error.c   |  8 ++++----
 6 files changed, 30 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 81cd21ecfa7d..62208b3bf417 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -596,7 +596,7 @@ struct drm_i915_file_private {
  * to limit the badly behaving clients access to gpu.
  */
 #define I915_MAX_CLIENT_CONTEXT_BANS 3
-	int context_bans;
+	atomic_t context_bans;
 };
 
 /* Used by dp and fdi links */
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 1564cadda94d..cbe70a94b663 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2739,34 +2739,38 @@ i915_gem_object_pwrite_gtt(struct drm_i915_gem_object *obj,
 	return 0;
 }
 
-static bool ban_context(const struct i915_gem_context *ctx)
+static bool ban_context(const struct i915_gem_context *ctx,
+			unsigned int score)
 {
 	return (i915_gem_context_is_bannable(ctx) &&
-		ctx->ban_score >= CONTEXT_SCORE_BAN_THRESHOLD);
+		score >= CONTEXT_SCORE_BAN_THRESHOLD);
 }
 
 static void i915_gem_context_mark_guilty(struct i915_gem_context *ctx)
 {
-	ctx->guilty_count++;
-	ctx->ban_score += CONTEXT_SCORE_GUILTY;
-	if (ban_context(ctx))
-		i915_gem_context_set_banned(ctx);
+	unsigned int score;
+	bool banned;
 
-	DRM_DEBUG_DRIVER("context %s marked guilty (score %d) banned? %s\n",
-			 ctx->name, ctx->ban_score,
-			 yesno(i915_gem_context_is_banned(ctx)));
+	atomic_inc(&ctx->guilty_count);
 
-	if (!i915_gem_context_is_banned(ctx) || IS_ERR_OR_NULL(ctx->file_priv))
+	score = atomic_add_return(CONTEXT_SCORE_GUILTY, &ctx->ban_score);
+	banned = ban_context(ctx, score);
+	DRM_DEBUG_DRIVER("context %s marked guilty (score %d) banned? %s\n",
+			 ctx->name, score, yesno(banned));
+	if (!banned)
 		return;
 
-	ctx->file_priv->context_bans++;
-	DRM_DEBUG_DRIVER("client %s has had %d context banned\n",
-			 ctx->name, ctx->file_priv->context_bans);
+	i915_gem_context_set_banned(ctx);
+	if (!IS_ERR_OR_NULL(ctx->file_priv)) {
+		atomic_inc(&ctx->file_priv->context_bans);
+		DRM_DEBUG_DRIVER("client %s has had %d context banned\n",
+				 ctx->name, atomic_read(&ctx->file_priv->context_bans));
+	}
 }
 
 static void i915_gem_context_mark_innocent(struct i915_gem_context *ctx)
 {
-	ctx->active_count++;
+	atomic_inc(&ctx->active_count);
 }
 
 struct drm_i915_gem_request *
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 1a87d04e7937..ed91ac8ca832 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -977,7 +977,7 @@ int i915_gem_switch_to_kernel_context(struct drm_i915_private *dev_priv)
 
 static bool client_is_banned(struct drm_i915_file_private *file_priv)
 {
-	return file_priv->context_bans > I915_MAX_CLIENT_CONTEXT_BANS;
+	return atomic_read(&file_priv->context_bans) > I915_MAX_CLIENT_CONTEXT_BANS;
 }
 
 int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
@@ -1179,8 +1179,8 @@ int i915_gem_context_reset_stats_ioctl(struct drm_device *dev,
 	else
 		args->reset_count = 0;
 
-	args->batch_active = READ_ONCE(ctx->guilty_count);
-	args->batch_pending = READ_ONCE(ctx->active_count);
+	args->batch_active = atomic_read(&ctx->guilty_count);
+	args->batch_pending = atomic_read(&ctx->active_count);
 
 	ret = 0;
 out:
diff --git a/drivers/gpu/drm/i915/i915_gem_context.h b/drivers/gpu/drm/i915/i915_gem_context.h
index 04320f80f9f4..2d02918a449e 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.h
+++ b/drivers/gpu/drm/i915/i915_gem_context.h
@@ -191,17 +191,17 @@ struct i915_gem_context {
 	u32 desc_template;
 
 	/** guilty_count: How many times this context has caused a GPU hang. */
-	unsigned int guilty_count;
+	atomic_t guilty_count;
 	/**
 	 * @active_count: How many times this context was active during a GPU
 	 * hang, but did not cause it.
 	 */
-	unsigned int active_count;
+	atomic_t active_count;
 
 #define CONTEXT_SCORE_GUILTY		10
 #define CONTEXT_SCORE_BAN_THRESHOLD	40
 	/** ban_score: Accumulated score of all hangs caused by this context. */
-	int ban_score;
+	atomic_t ban_score;
 
 	/** remap_slice: Bitmask of cache lines that need remapping */
 	u8 remap_slice;
diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
index 483af8921060..8ba89abe5441 100644
--- a/drivers/gpu/drm/i915/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/i915_gem_request.c
@@ -370,8 +370,7 @@ static void i915_gem_request_retire(struct drm_i915_gem_request *request)
 	i915_gem_request_remove_from_client(request);
 
 	/* Retirement decays the ban score as it is a sign of ctx progress */
-	if (request->ctx->ban_score > 0)
-		request->ctx->ban_score--;
+	atomic_dec_if_positive(&request->ctx->ban_score);
 
 	/* The backing object for the context is done after switching to the
 	 * *next* context. Therefore we cannot retire the previous context until
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index ae70283470a6..ed5a1eb839ad 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1266,7 +1266,7 @@ static void record_request(struct drm_i915_gem_request *request,
 			   struct drm_i915_error_request *erq)
 {
 	erq->context = request->ctx->hw_id;
-	erq->ban_score = request->ctx->ban_score;
+	erq->ban_score = atomic_read(&request->ctx->ban_score);
 	erq->seqno = request->global_seqno;
 	erq->jiffies = request->emitted_jiffies;
 	erq->head = request->head;
@@ -1357,9 +1357,9 @@ static void record_context(struct drm_i915_error_context *e,
 
 	e->handle = ctx->user_handle;
 	e->hw_id = ctx->hw_id;
-	e->ban_score = ctx->ban_score;
-	e->guilty = ctx->guilty_count;
-	e->active = ctx->active_count;
+	e->ban_score = atomic_read(&ctx->ban_score);
+	e->guilty = atomic_read(&ctx->guilty_count);
+	e->active = atomic_read(&ctx->active_count);
 }
 
 static void request_record_user_bo(struct drm_i915_gem_request *request,
-- 
2.13.2

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2017-07-11 11:28 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-07-09  9:35 [PATCH] drm/i915: Make i915_gem_context_mark_guilty() safe for unlocked updates Chris Wilson
2017-07-09  9:53 ` ✓ Fi.CI.BAT: success for " Patchwork
2017-07-10 14:14 ` [PATCH] " Mika Kuoppala
2017-07-11 11:27   ` Chris Wilson

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox