From patchwork Thu May 11 15:43:31 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lionel Landwerlin X-Patchwork-Id: 9722221 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 F1A3060364 for ; Thu, 11 May 2017 15:44:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E728824151 for ; Thu, 11 May 2017 15:44:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DC25A286AC; Thu, 11 May 2017 15:44:04 +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=-4.2 required=2.0 tests=BAYES_00, 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 8649824151 for ; Thu, 11 May 2017 15:44:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 34DFE6E570; Thu, 11 May 2017 15:44:04 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id E693D6E569 for ; Thu, 11 May 2017 15:44:02 +0000 (UTC) Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP; 11 May 2017 08:44:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,324,1491289200"; d="scan'208";a="967316057" Received: from delly.ld.intel.com ([10.103.239.164]) by orsmga003.jf.intel.com with ESMTP; 11 May 2017 08:44:01 -0700 From: Lionel Landwerlin To: intel-gfx@lists.freedesktop.org Date: Thu, 11 May 2017 16:43:31 +0100 Message-Id: <20170511154345.962-9-lionel.g.landwerlin@intel.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170511154345.962-1-lionel.g.landwerlin@intel.com> References: <20170511154345.962-1-lionel.g.landwerlin@intel.com> Subject: [Intel-gfx] [PATCH 08/22] drm/i915/perf: rate limit spurious oa report notice X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 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 From: Robert Bragg This change is pre-emptively aiming to avoid a potential cause of kernel logging noise in case some condition were to result in us seeing invalid OA reports. The workaround for the OA unit's tail pointer race condition is what avoids the primary known cause of invalid reports being seen and with that in place we aren't expecting to see this notice but it can't be entirely ruled out. Just in case some condition does lead to the notice then it's likely that it will be triggered repeatedly while attempting to append a sequence of reports and depending on the configured OA sampling frequency that might be a large number of repeat notices. v2: (Chris) avoid inconsistent warning on throttle with printk_ratelimit() v3: (Matt) init and summarise with stream init/close not driver init/fini Signed-off-by: Robert Bragg Reviewed-by: Matthew Auld --- drivers/gpu/drm/i915/i915_drv.h | 6 ++++++ drivers/gpu/drm/i915/i915_perf.c | 28 +++++++++++++++++++++++++++- 2 files changed, 33 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 22b2ea3ea66f..66dee15e4fc0 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2354,6 +2354,12 @@ struct drm_i915_private { wait_queue_head_t poll_wq; bool pollin; + /** + * For rate limiting any notifications of spurious + * invalid OA reports + */ + struct ratelimit_state spurious_report_rs; + bool periodic; int period_exponent; diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c index dbed19a5a1b2..665a3c53e388 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -632,7 +632,8 @@ static int gen7_append_oa_reports(struct i915_perf_stream *stream, * copying it to userspace... */ if (report32[0] == 0) { - DRM_NOTE("Skipping spurious, invalid OA report\n"); + if (__ratelimit(&dev_priv->perf.oa.spurious_report_rs)) + DRM_NOTE("Skipping spurious, invalid OA report\n"); continue; } @@ -912,6 +913,11 @@ static void i915_oa_stream_destroy(struct i915_perf_stream *stream) oa_put_render_ctx_id(stream); dev_priv->perf.oa.exclusive_stream = NULL; + + if (dev_priv->perf.oa.spurious_report_rs.missed) { + DRM_NOTE("%d spurious OA report notices suppressed due to ratelimiting\n", + dev_priv->perf.oa.spurious_report_rs.missed); + } } static void gen7_init_oa_buffer(struct drm_i915_private *dev_priv) @@ -1267,6 +1273,26 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream, return -EINVAL; } + /* We set up some ratelimit state to potentially throttle any _NOTES + * about spurious, invalid OA reports which we don't forward to + * userspace. + * + * The initialization is associated with opening the stream (not driver + * init) considering we print a _NOTE about any throttling when closing + * the stream instead of waiting until driver _fini which no one would + * ever see. + * + * Using the same limiting factors as printk_ratelimit() + */ + ratelimit_state_init(&dev_priv->perf.oa.spurious_report_rs, + 5 * HZ, 10); + /* Since we use a DRM_NOTE for spurious reports it would be + * inconsistent to let __ratelimit() automatically print a warning for + * throttling. + */ + ratelimit_set_flags(&dev_priv->perf.oa.spurious_report_rs, + RATELIMIT_MSG_ON_RELEASE); + stream->sample_size = sizeof(struct drm_i915_perf_record_header); format_size = dev_priv->perf.oa.oa_formats[props->oa_format].size;