From patchwork Thu May 27 16:26:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Ekstrand X-Patchwork-Id: 12284807 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7813CC4708C for ; Thu, 27 May 2021 16:27:52 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 47FE561003 for ; Thu, 27 May 2021 16:27:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 47FE561003 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=jlekstrand.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 19C866F466; Thu, 27 May 2021 16:27:34 +0000 (UTC) Received: from mail-pf1-x42d.google.com (mail-pf1-x42d.google.com [IPv6:2607:f8b0:4864:20::42d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 149416F463 for ; Thu, 27 May 2021 16:27:31 +0000 (UTC) Received: by mail-pf1-x42d.google.com with SMTP id x18so964138pfi.9 for ; Thu, 27 May 2021 09:27:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jlekstrand-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=dYGl6aSfW5uO4C2yC1IUa1a1lP1+xk+jzBkSn02eNm4=; b=1QyRyBXc4KaXsnt8KJWbZDmDK6eEZCV9IUAh6hBNkTRAIYkuLkhYbUVOVYma/pTh5n 7L3AMuL74mq5AcVUgxQoECWIzPZA0wlu5echPyKLIBAEda2BNWwroHd0Nu0Ni17ZVRCs 9F7CqYeQNtVPN9VtDEP9UMte9IxPh3jDzZmD2SeKYl1cuzfgML94INJhJNnccSvrjTGB 3DFBnnUYrRgwcO86ARR7mujPN/2rgh1I6POVD68wcZSOARDtI3xgMFaKZ8JYHMo0+lBj RZZLTcAbD+eeJVgnH9bqsJ9cMc1YlxCt3nJhU+jK9WFSTsehGEGkWGFzXziOBlF8liyP +RrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=dYGl6aSfW5uO4C2yC1IUa1a1lP1+xk+jzBkSn02eNm4=; b=eQl39+iYwzDZW7bykcoJ5Tzs8UI7kQFuFk87q1vXTvcgR60fUGk0aPToGMYkJhmE3s RTW59yS24SwqVwZdX+xfcl9V8mbmt5rbMhc3K4kC5uKciHf2eZmF8Kkb/HzluBQvaTI8 q2ziBK/Fex9f1szzyohqZWmdJRMgd2F9m68kkyZckBNznEjOsGWRrBHzDPvOjeHgEQY3 KpjZZrZWfk/PbG91kRJyA4Ajdum9VOOY1O8QbT7TdY5rmlLG5IoIic7k1/ONsuTW/lHp nBTcRLTAglluH5mRvNWs3WcY97iC0M6W/v+scR5AD/pSsLDQU7Kn1lJm3Gphxg1cLcTU XIgA== X-Gm-Message-State: AOAM532T2FiJwPbLO5/Dg6ocyzESCzX+udZQOOqBWnZ6SAsTdYg/jxnV K8RBG0cAcmMFoeXmAzaFYaA3WQ== X-Google-Smtp-Source: ABdhPJyJzXtFTFvE0E0XoyQWkol8jaLa8S4uDD03wpcPeMhdH1dxgJP9G0a5gkib80EbXAzmWeHUWw== X-Received: by 2002:a63:ba5b:: with SMTP id l27mr4424916pgu.343.1622132850508; Thu, 27 May 2021 09:27:30 -0700 (PDT) Received: from omlet.com ([134.134.139.83]) by smtp.gmail.com with ESMTPSA id h9sm2298711pja.42.2021.05.27.09.27.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 May 2021 09:27:30 -0700 (PDT) From: Jason Ekstrand To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Subject: [PATCH 25/29] drm/i915/gem: Don't allow changing the VM on running contexts (v2) Date: Thu, 27 May 2021 11:26:46 -0500 Message-Id: <20210527162650.1182544-26-jason@jlekstrand.net> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210527162650.1182544-1-jason@jlekstrand.net> References: <20210527162650.1182544-1-jason@jlekstrand.net> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Ekstrand Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" When the APIs were added to manage VMs more directly from userspace, the questionable choice was made to allow changing out the VM on a context at any time. This is horribly racy and there's absolutely no reason why any userspace would want to do this outside of testing that exact race. By removing support for CONTEXT_PARAM_VM from ctx_setparam, we make it impossible to change out the VM after the context has been fully created. This lets us delete a bunch of deferred task code as well as a duplicated (and slightly different) copy of the code which programs the PPGTT registers. v2 (Jason Ekstrand): - Expand the commit message Signed-off-by: Jason Ekstrand --- drivers/gpu/drm/i915/gem/i915_gem_context.c | 262 ------------------ .../gpu/drm/i915/gem/i915_gem_context_types.h | 2 +- .../drm/i915/gem/selftests/i915_gem_context.c | 119 -------- .../drm/i915/selftests/i915_mock_selftests.h | 1 - 4 files changed, 1 insertion(+), 383 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c index f7c83730ee07f..a528c8f3354a0 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c @@ -1633,120 +1633,6 @@ int i915_gem_vm_destroy_ioctl(struct drm_device *dev, void *data, return 0; } -struct context_barrier_task { - struct i915_active base; - void (*task)(void *data); - void *data; -}; - -static void cb_retire(struct i915_active *base) -{ - struct context_barrier_task *cb = container_of(base, typeof(*cb), base); - - if (cb->task) - cb->task(cb->data); - - i915_active_fini(&cb->base); - kfree(cb); -} - -I915_SELFTEST_DECLARE(static intel_engine_mask_t context_barrier_inject_fault); -static int context_barrier_task(struct i915_gem_context *ctx, - intel_engine_mask_t engines, - bool (*skip)(struct intel_context *ce, void *data), - int (*pin)(struct intel_context *ce, struct i915_gem_ww_ctx *ww, void *data), - int (*emit)(struct i915_request *rq, void *data), - void (*task)(void *data), - void *data) -{ - struct context_barrier_task *cb; - struct i915_gem_engines_iter it; - struct i915_gem_engines *e; - struct i915_gem_ww_ctx ww; - struct intel_context *ce; - int err = 0; - - GEM_BUG_ON(!task); - - cb = kmalloc(sizeof(*cb), GFP_KERNEL); - if (!cb) - return -ENOMEM; - - i915_active_init(&cb->base, NULL, cb_retire, 0); - err = i915_active_acquire(&cb->base); - if (err) { - kfree(cb); - return err; - } - - e = __context_engines_await(ctx, NULL); - if (!e) { - i915_active_release(&cb->base); - return -ENOENT; - } - - for_each_gem_engine(ce, e, it) { - struct i915_request *rq; - - if (I915_SELFTEST_ONLY(context_barrier_inject_fault & - ce->engine->mask)) { - err = -ENXIO; - break; - } - - if (!(ce->engine->mask & engines)) - continue; - - if (skip && skip(ce, data)) - continue; - - i915_gem_ww_ctx_init(&ww, true); -retry: - err = intel_context_pin_ww(ce, &ww); - if (err) - goto err; - - if (pin) - err = pin(ce, &ww, data); - if (err) - goto err_unpin; - - rq = i915_request_create(ce); - if (IS_ERR(rq)) { - err = PTR_ERR(rq); - goto err_unpin; - } - - err = 0; - if (emit) - err = emit(rq, data); - if (err == 0) - err = i915_active_add_request(&cb->base, rq); - - i915_request_add(rq); -err_unpin: - intel_context_unpin(ce); -err: - if (err == -EDEADLK) { - err = i915_gem_ww_ctx_backoff(&ww); - if (!err) - goto retry; - } - i915_gem_ww_ctx_fini(&ww); - - if (err) - break; - } - i915_sw_fence_complete(&e->fence); - - cb->task = err ? NULL : task; /* caller needs to unwind instead */ - cb->data = data; - - i915_active_release(&cb->base); - - return err; -} - static int get_ppgtt(struct drm_i915_file_private *file_priv, struct i915_gem_context *ctx, struct drm_i915_gem_context_param *args) @@ -1779,150 +1665,6 @@ static int get_ppgtt(struct drm_i915_file_private *file_priv, return err; } -static void set_ppgtt_barrier(void *data) -{ - struct i915_address_space *old = data; - - if (INTEL_GEN(old->i915) < 8) - gen6_ppgtt_unpin_all(i915_vm_to_ppgtt(old)); - - i915_vm_close(old); -} - -static int pin_ppgtt_update(struct intel_context *ce, struct i915_gem_ww_ctx *ww, void *data) -{ - struct i915_address_space *vm = ce->vm; - - if (!HAS_LOGICAL_RING_CONTEXTS(vm->i915)) - /* ppGTT is not part of the legacy context image */ - return gen6_ppgtt_pin(i915_vm_to_ppgtt(vm), ww); - - return 0; -} - -static int emit_ppgtt_update(struct i915_request *rq, void *data) -{ - struct i915_address_space *vm = rq->context->vm; - struct intel_engine_cs *engine = rq->engine; - u32 base = engine->mmio_base; - u32 *cs; - int i; - - if (i915_vm_is_4lvl(vm)) { - struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm); - const dma_addr_t pd_daddr = px_dma(ppgtt->pd); - - cs = intel_ring_begin(rq, 6); - if (IS_ERR(cs)) - return PTR_ERR(cs); - - *cs++ = MI_LOAD_REGISTER_IMM(2); - - *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_UDW(base, 0)); - *cs++ = upper_32_bits(pd_daddr); - *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_LDW(base, 0)); - *cs++ = lower_32_bits(pd_daddr); - - *cs++ = MI_NOOP; - intel_ring_advance(rq, cs); - } else if (HAS_LOGICAL_RING_CONTEXTS(engine->i915)) { - struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm); - int err; - - /* Magic required to prevent forcewake errors! */ - err = engine->emit_flush(rq, EMIT_INVALIDATE); - if (err) - return err; - - cs = intel_ring_begin(rq, 4 * GEN8_3LVL_PDPES + 2); - if (IS_ERR(cs)) - return PTR_ERR(cs); - - *cs++ = MI_LOAD_REGISTER_IMM(2 * GEN8_3LVL_PDPES) | MI_LRI_FORCE_POSTED; - for (i = GEN8_3LVL_PDPES; i--; ) { - const dma_addr_t pd_daddr = i915_page_dir_dma_addr(ppgtt, i); - - *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_UDW(base, i)); - *cs++ = upper_32_bits(pd_daddr); - *cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_LDW(base, i)); - *cs++ = lower_32_bits(pd_daddr); - } - *cs++ = MI_NOOP; - intel_ring_advance(rq, cs); - } - - return 0; -} - -static bool skip_ppgtt_update(struct intel_context *ce, void *data) -{ - if (HAS_LOGICAL_RING_CONTEXTS(ce->engine->i915)) - return !ce->state; - else - return !atomic_read(&ce->pin_count); -} - -static int set_ppgtt(struct drm_i915_file_private *file_priv, - struct i915_gem_context *ctx, - struct drm_i915_gem_context_param *args) -{ - struct i915_address_space *vm, *old; - int err; - - if (args->size) - return -EINVAL; - - if (!rcu_access_pointer(ctx->vm)) - return -ENODEV; - - if (upper_32_bits(args->value)) - return -ENOENT; - - vm = i915_gem_vm_lookup(file_priv, args->value); - if (!vm) - return -ENOENT; - - err = mutex_lock_interruptible(&ctx->mutex); - if (err) - goto out; - - if (i915_gem_context_is_closed(ctx)) { - err = -ENOENT; - goto unlock; - } - - if (vm == rcu_access_pointer(ctx->vm)) - goto unlock; - - old = __set_ppgtt(ctx, vm); - - /* Teardown the existing obj:vma cache, it will have to be rebuilt. */ - lut_close(ctx); - - /* - * We need to flush any requests using the current ppgtt before - * we release it as the requests do not hold a reference themselves, - * only indirectly through the context. - */ - err = context_barrier_task(ctx, ALL_ENGINES, - skip_ppgtt_update, - pin_ppgtt_update, - emit_ppgtt_update, - set_ppgtt_barrier, - old); - if (err) { - i915_vm_close(__set_ppgtt(ctx, old)); - i915_vm_close(old); - lut_close(ctx); /* force a rebuild of the old obj:vma cache */ - } - -unlock: - mutex_unlock(&ctx->mutex); -out: - i915_vm_put(vm); - return err; -} - int i915_gem_user_to_context_sseu(struct intel_gt *gt, const struct drm_i915_gem_context_param_sseu *user, @@ -2458,10 +2200,6 @@ static int ctx_setparam(struct drm_i915_file_private *fpriv, ret = set_sseu(ctx, args); break; - case I915_CONTEXT_PARAM_VM: - ret = set_ppgtt(fpriv, ctx, args); - break; - case I915_CONTEXT_PARAM_ENGINES: ret = set_engines(ctx, args); break; diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h index b673061f4f5ba..84c821cca1739 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h @@ -262,7 +262,7 @@ struct i915_gem_context { * In other modes, this is a NULL pointer with the expectation that * the caller uses the shared global GTT. */ - struct i915_address_space __rcu *vm; + struct i915_address_space *vm; /** * @pid: process id of creator diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c index ce70d0a3afb26..506cd9e9d4b25 100644 --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c @@ -1875,125 +1875,6 @@ static int igt_vm_isolation(void *arg) return err; } -static bool skip_unused_engines(struct intel_context *ce, void *data) -{ - return !ce->state; -} - -static void mock_barrier_task(void *data) -{ - unsigned int *counter = data; - - ++*counter; -} - -static int mock_context_barrier(void *arg) -{ -#undef pr_fmt -#define pr_fmt(x) "context_barrier_task():" # x - struct drm_i915_private *i915 = arg; - struct i915_gem_context *ctx; - struct i915_request *rq; - unsigned int counter; - int err; - - /* - * The context barrier provides us with a callback after it emits - * a request; useful for retiring old state after loading new. - */ - - ctx = mock_context(i915, "mock"); - if (!ctx) - return -ENOMEM; - - counter = 0; - err = context_barrier_task(ctx, 0, NULL, NULL, NULL, - mock_barrier_task, &counter); - if (err) { - pr_err("Failed at line %d, err=%d\n", __LINE__, err); - goto out; - } - if (counter == 0) { - pr_err("Did not retire immediately with 0 engines\n"); - err = -EINVAL; - goto out; - } - - counter = 0; - err = context_barrier_task(ctx, ALL_ENGINES, skip_unused_engines, - NULL, NULL, mock_barrier_task, &counter); - if (err) { - pr_err("Failed at line %d, err=%d\n", __LINE__, err); - goto out; - } - if (counter == 0) { - pr_err("Did not retire immediately for all unused engines\n"); - err = -EINVAL; - goto out; - } - - rq = igt_request_alloc(ctx, i915->gt.engine[RCS0]); - if (IS_ERR(rq)) { - pr_err("Request allocation failed!\n"); - goto out; - } - i915_request_add(rq); - - counter = 0; - context_barrier_inject_fault = BIT(RCS0); - err = context_barrier_task(ctx, ALL_ENGINES, NULL, NULL, NULL, - mock_barrier_task, &counter); - context_barrier_inject_fault = 0; - if (err == -ENXIO) - err = 0; - else - pr_err("Did not hit fault injection!\n"); - if (counter != 0) { - pr_err("Invoked callback on error!\n"); - err = -EIO; - } - if (err) - goto out; - - counter = 0; - err = context_barrier_task(ctx, ALL_ENGINES, skip_unused_engines, - NULL, NULL, mock_barrier_task, &counter); - if (err) { - pr_err("Failed at line %d, err=%d\n", __LINE__, err); - goto out; - } - mock_device_flush(i915); - if (counter == 0) { - pr_err("Did not retire on each active engines\n"); - err = -EINVAL; - goto out; - } - -out: - mock_context_close(ctx); - return err; -#undef pr_fmt -#define pr_fmt(x) x -} - -int i915_gem_context_mock_selftests(void) -{ - static const struct i915_subtest tests[] = { - SUBTEST(mock_context_barrier), - }; - struct drm_i915_private *i915; - int err; - - i915 = mock_gem_device(); - if (!i915) - return -ENOMEM; - - err = i915_subtests(tests, i915); - - mock_destroy_device(i915); - return err; -} - int i915_gem_context_live_selftests(struct drm_i915_private *i915) { static const struct i915_subtest tests[] = { diff --git a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h index 3db34d3eea58a..52aa91716dc1f 100644 --- a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h +++ b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h @@ -32,6 +32,5 @@ selftest(vma, i915_vma_mock_selftests) selftest(evict, i915_gem_evict_mock_selftests) selftest(gtt, i915_gem_gtt_mock_selftests) selftest(hugepages, i915_gem_huge_page_mock_selftests) -selftest(contexts, i915_gem_context_mock_selftests) selftest(buddy, i915_buddy_mock_selftests) selftest(memory_region, intel_memory_region_mock_selftests)