From 77b25a972b5d4ed93b8a86d3e383ec2092fd89b1 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 21 Jul 2017 13:32:30 +0100 Subject: [PATCH] drm/i915: Make i915_gem_context_mark_guilty() safe for unlocked updates 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 Cc: Michel Thierry Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20170721123238.16428-12-chris@chris-wilson.co.uk Signed-off-by: Daniel Vetter --- 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 ef089fe0353e..b051122c960b 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -602,7 +602,7 @@ 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 fcf7fee7ca71..a9ea83ea321b 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2740,34 +2740,38 @@ 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 d93a185c0f0a..68e406a53c04 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -374,8 +374,7 @@ 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, -- 2.11.0