From patchwork Wed Aug 1 17:04:19 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10552719 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7915313BF for ; Wed, 1 Aug 2018 17:04:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6471720072 for ; Wed, 1 Aug 2018 17:04:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 583B2283EE; Wed, 1 Aug 2018 17:04:37 +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 5D55320072 for ; Wed, 1 Aug 2018 17:04:36 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 607766E499; Wed, 1 Aug 2018 17:04:35 +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 66A246E499 for ; Wed, 1 Aug 2018 17:04:33 +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 12537682-1500050 for multiple; Wed, 01 Aug 2018 18:04:21 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Wed, 1 Aug 2018 18:04:19 +0100 Message-Id: <20180801170419.1085-2-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801170419.1085-1-chris@chris-wilson.co.uk> References: <20180801170419.1085-1-chris@chris-wilson.co.uk> Subject: [Intel-gfx] [PATCH 2/2] drm/i915: Dampen RPS slow start 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: , Cc: Mika Kuoppala MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Currently, we note congestion for the slow start ramping up of RPS only when we overshoot the target workload and have to reverse direction for our reclocking. That is, if we have a period where the current GPU frequency is enough to sustain the workload within our target utilisation, we should not trigger any RPS EI interrupts, and then may continue again with the previous last_adj after multiple periods causing us to dramatically overreact. To prevent us not noticing a period where the system is behaving correctly, we can schedule an extra interrupt that will not be associated with either an up or down event causing to reset last_adj back to zero, cancelling the slow start due to the congestion. Signed-off-by: Chris Wilson Cc: Mika Kuoppala --- drivers/gpu/drm/i915/i915_irq.c | 13 +++++++++---- drivers/gpu/drm/i915/intel_pm.c | 15 +++++++++++---- 2 files changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 90628a47ae17..e2ee1e13cec7 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -1297,6 +1297,7 @@ static void gen6_pm_rps_work(struct work_struct *work) goto out; mutex_lock(&dev_priv->pcu_lock); + dev_priv->pm_rps_events &= ~GEN6_PM_RP_DOWN_EI_EXPIRED; pm_iir |= vlv_wa_c0_ei(dev_priv, pm_iir); @@ -1310,10 +1311,12 @@ static void gen6_pm_rps_work(struct work_struct *work) new_delay = rps->boost_freq; adj = 0; } else if (pm_iir & GEN6_PM_RP_UP_THRESHOLD) { - if (adj > 0) + if (adj > 0) { + dev_priv->pm_rps_events |= GEN6_PM_RP_DOWN_EI_EXPIRED; adj *= 2; - else /* CHV needs even encode values */ + } else { /* CHV needs even encode values */ adj = IS_CHERRYVIEW(dev_priv) ? 2 : 1; + } if (new_delay >= rps->max_freq_softlimit) adj = 0; @@ -1326,10 +1329,12 @@ static void gen6_pm_rps_work(struct work_struct *work) new_delay = rps->min_freq_softlimit; adj = 0; } else if (pm_iir & GEN6_PM_RP_DOWN_THRESHOLD) { - if (adj < 0) + if (adj < 0) { + dev_priv->pm_rps_events |= GEN6_PM_RP_DOWN_EI_EXPIRED; adj *= 2; - else /* CHV needs even encode values */ + } else { /* CHV needs even encode values */ adj = IS_CHERRYVIEW(dev_priv) ? -2 : -1; + } if (new_delay <= rps->min_freq_softlimit) adj = 0; diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index f90a3c7f1c40..321a0acd274a 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -6397,10 +6397,17 @@ static u32 gen6_rps_pm_mask(struct drm_i915_private *dev_priv, u8 val) u32 mask = 0; /* We use UP_EI_EXPIRED interupts for both up/down in manual mode */ - if (val > rps->min_freq_softlimit) - mask |= GEN6_PM_RP_UP_EI_EXPIRED | GEN6_PM_RP_DOWN_THRESHOLD | GEN6_PM_RP_DOWN_TIMEOUT; - if (val < rps->max_freq_softlimit) - mask |= GEN6_PM_RP_UP_EI_EXPIRED | GEN6_PM_RP_UP_THRESHOLD; + if (val > rps->min_freq_softlimit) { + mask |= (GEN6_PM_RP_UP_EI_EXPIRED | + GEN6_PM_RP_DOWN_EI_EXPIRED | + GEN6_PM_RP_DOWN_THRESHOLD | + GEN6_PM_RP_DOWN_TIMEOUT); + } + if (val < rps->max_freq_softlimit) { + mask |= (GEN6_PM_RP_UP_EI_EXPIRED | + GEN6_PM_RP_DOWN_EI_EXPIRED | + GEN6_PM_RP_UP_THRESHOLD); + } mask &= dev_priv->pm_rps_events;