From patchwork Thu May 3 06:37:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10377163 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9444E6037D for ; Thu, 3 May 2018 06:39:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 852FF251F9 for ; Thu, 3 May 2018 06:39:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 79BA228E2B; Thu, 3 May 2018 06:39:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id E239A251F9 for ; Thu, 3 May 2018 06:39:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 11DE86E6A8; Thu, 3 May 2018 06:38:59 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 482A66E6A5 for ; Thu, 3 May 2018 06:38:56 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 11578257-1500050 for multiple; Thu, 03 May 2018 07:38:53 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Thu, 03 May 2018 07:38:51 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 3 May 2018 07:37:10 +0100 Message-Id: <20180503063757.22238-24-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180503063757.22238-1-chris@chris-wilson.co.uk> References: <20180503063757.22238-1-chris@chris-wilson.co.uk> X-Originating-IP: 78.156.65.138 X-Country: code=GB country="United Kingdom" ip=78.156.65.138 Subject: [Intel-gfx] [PATCH 24/71] drm/i915: Allow user control over preempt timeout on their important context X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP One usecase would be to couple in via EGL_NV_context_priority_realtime in userspace to provide some QoS guarantees in conjunction with setting the highest priority. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_gem_context.c | 22 ++++++ drivers/gpu/drm/i915/i915_gem_context.h | 13 ++++ drivers/gpu/drm/i915/i915_request.c | 7 +- drivers/gpu/drm/i915/intel_lrc.c | 3 +- drivers/gpu/drm/i915/selftests/intel_lrc.c | 85 ++++++++++++++++++++++ include/uapi/drm/i915_drm.h | 12 +++ 6 files changed, 139 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index 66aad55c5273..dccae45211d1 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -755,6 +755,15 @@ int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data, case I915_CONTEXT_PARAM_PRIORITY: args->value = ctx->sched.priority; break; + case I915_CONTEXT_PARAM_PREEMPT_TIMEOUT: + if (!(to_i915(dev)->caps.scheduler & I915_SCHEDULER_CAP_PREEMPTION)) + ret = -ENODEV; + else if (args->size) + ret = -EINVAL; + else + args->value = ctx->preempt_timeout; + break; + default: ret = -EINVAL; break; @@ -830,6 +839,19 @@ int i915_gem_context_setparam_ioctl(struct drm_device *dev, void *data, } break; + case I915_CONTEXT_PARAM_PREEMPT_TIMEOUT: + if (args->size) + ret = -EINVAL; + else if (args->value > U32_MAX) + ret = -EINVAL; + else if (!(to_i915(dev)->caps.scheduler & I915_SCHEDULER_CAP_PREEMPTION)) + ret = -ENODEV; + else if (args->value && !capable(CAP_SYS_ADMIN)) + ret = -EPERM; + else + ctx->preempt_timeout = args->value; + break; + default: ret = -EINVAL; break; diff --git a/drivers/gpu/drm/i915/i915_gem_context.h b/drivers/gpu/drm/i915/i915_gem_context.h index 749a4ff566f5..23c88902bbc3 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.h +++ b/drivers/gpu/drm/i915/i915_gem_context.h @@ -144,6 +144,19 @@ struct i915_gem_context { struct i915_sched_attr sched; + /** + * @preempt_timeout: QoS guarantee for the high priority context + * + * Some clients need a guarantee that they will start executing + * within a certain window, even at the expense of others. This entails + * that if a preemption request is not honoured by the active context + * within the timeout, we will reset the GPU to evict the hog and + * run the high priority context instead. + * + * Timeout is stored in nanoseconds. + */ + u32 preempt_timeout; + /** ggtt_offset_bias: placement restriction for context objects */ u32 ggtt_offset_bias; diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 76ee297483b1..17842549177a 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -1110,8 +1110,11 @@ void __i915_request_add(struct i915_request *request, bool flush_caches) * run at the earliest possible convenience. */ local_bh_disable(); - if (engine->schedule) - engine->schedule(request, &request->gem_context->sched, 0); + if (engine->schedule) { + engine->schedule(request, + &request->gem_context->sched, + request->gem_context->preempt_timeout); + } i915_sw_fence_commit(&request->submit); local_bh_enable(); /* Kick the execlists tasklet if just scheduled */ diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 8ddb1351c5ce..994e945a2e2d 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1292,7 +1292,8 @@ static void execlists_submit_request(struct i915_request *request) spin_lock_irqsave(&engine->timeline.lock, flags); queue_request(engine, &request->sched, rq_prio(request)); - submit_queue(engine, rq_prio(request), 0); + submit_queue(engine, + rq_prio(request), request->gem_context->preempt_timeout); GEM_BUG_ON(!engine->execlists.first); GEM_BUG_ON(list_empty(&request->sched.link)); diff --git a/drivers/gpu/drm/i915/selftests/intel_lrc.c b/drivers/gpu/drm/i915/selftests/intel_lrc.c index ec906914bee2..1f30f45d2532 100644 --- a/drivers/gpu/drm/i915/selftests/intel_lrc.c +++ b/drivers/gpu/drm/i915/selftests/intel_lrc.c @@ -790,6 +790,90 @@ static int live_late_preempt_timeout(void *arg) goto err_ctx_lo; } +static int live_context_preempt_timeout(void *arg) +{ + struct drm_i915_private *i915 = arg; + struct i915_gem_context *ctx_hi, *ctx_lo; + struct spinner spin_hi, spin_lo; + struct intel_engine_cs *engine; + enum intel_engine_id id; + int err = -ENOMEM; + + if (!HAS_LOGICAL_RING_PREEMPTION(i915)) + return 0; + + mutex_lock(&i915->drm.struct_mutex); + + if (spinner_init(&spin_hi, i915)) + goto err_unlock; + + if (spinner_init(&spin_lo, i915)) + goto err_spin_hi; + + ctx_hi = kernel_context(i915); + if (!ctx_hi) + goto err_spin_lo; + ctx_hi->sched.priority = I915_CONTEXT_MAX_USER_PRIORITY; + ctx_hi->preempt_timeout = 50 * 1000; /* 50us */ + + ctx_lo = kernel_context(i915); + if (!ctx_lo) + goto err_ctx_hi; + ctx_lo->sched.priority = I915_CONTEXT_MIN_USER_PRIORITY; + + for_each_engine(engine, i915, id) { + struct i915_request *rq; + + rq = spinner_create_request(&spin_lo, ctx_lo, engine, MI_NOOP); + if (IS_ERR(rq)) { + err = PTR_ERR(rq); + goto err_ctx_lo; + } + + i915_request_add(rq); + if (!wait_for_spinner(&spin_lo, rq)) { + i915_gem_set_wedged(i915); + err = -EIO; + goto err_ctx_lo; + } + + rq = spinner_create_request(&spin_hi, ctx_hi, engine, MI_NOOP); + if (IS_ERR(rq)) { + spinner_end(&spin_lo); + err = PTR_ERR(rq); + goto err_ctx_lo; + } + + i915_request_add(rq); + if (!wait_for_spinner(&spin_hi, rq)) { + i915_gem_set_wedged(i915); + err = -EIO; + goto err_ctx_lo; + } + + spinner_end(&spin_hi); + spinner_end(&spin_lo); + if (flush_test(i915, I915_WAIT_LOCKED)) { + err = -EIO; + goto err_ctx_lo; + } + } + + err = 0; +err_ctx_lo: + kernel_context_close(ctx_lo); +err_ctx_hi: + kernel_context_close(ctx_hi); +err_spin_lo: + spinner_fini(&spin_lo); +err_spin_hi: + spinner_fini(&spin_hi); +err_unlock: + flush_test(i915, I915_WAIT_LOCKED); + mutex_unlock(&i915->drm.struct_mutex); + return err; +} + int intel_execlists_live_selftests(struct drm_i915_private *i915) { static const struct i915_subtest tests[] = { @@ -799,6 +883,7 @@ int intel_execlists_live_selftests(struct drm_i915_private *i915) SUBTEST(live_preempt_timeout), SUBTEST(live_preempt_reset), SUBTEST(live_late_preempt_timeout), + SUBTEST(live_context_preempt_timeout), }; return i915_subtests(tests, i915); } diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index 7f5634ce8e88..853e0c7e0e85 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -1456,6 +1456,18 @@ struct drm_i915_gem_context_param { #define I915_CONTEXT_MAX_USER_PRIORITY 1023 /* inclusive */ #define I915_CONTEXT_DEFAULT_PRIORITY 0 #define I915_CONTEXT_MIN_USER_PRIORITY -1023 /* inclusive */ + +/* + * I915_CONTEXT_PARAM_PREEMPT_TIMEOUT: + * + * Preemption timeout give in nanoseconds. + * + * Only allowed for privileged clients (CAP_SYS_ADMIN), this property allows + * the preempting context to kick out a GPU hog using a GPU reset if they do + * not honour our preemption request in time. + */ +#define I915_CONTEXT_PARAM_PREEMPT_TIMEOUT 0x7 + __u64 value; };