From patchwork Wed May 31 23:56:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Umesh Nerlige Ramappa X-Patchwork-Id: 13262878 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 05B25C7EE2D for ; Wed, 31 May 2023 23:56:43 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E9F5A10E0E5; Wed, 31 May 2023 23:56:41 +0000 (UTC) Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5210110E0EB for ; Wed, 31 May 2023 23:56:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1685577399; x=1717113399; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=swzDPZb+z5zuueJPv3CmnWwF4FVuLRLvoMDXx0UcHbc=; b=AzEmK8u7js5+o3sR90v1tRGw6T0cO8tKsQ7vt43dHahrLfShD0Viwmoq lMC+7JMutO0fwWhBPRe0LieLThGLewzxCMh8MAc1ABwwZTm+jSbpcQdCq ntNfw/oi5jwv7C2QzYnPK0dj9WhtExhvp3xOX5QYZx0/JoSY9O4kxFu+q hZMzpqYADur0h6r5XkXx+jGxnlb+g/OJ5NyTfBXBLxsbP37/3ulayOps8 WCVrg8ZDtD9rXciQ1NI5h6GWaLr3q6VpgyjXq1E8lw6EELkzCVmgHZ7ZM XV1C/cE/vTgyau6S2gszxhcMI2ZvbXz+D7Tzy8WmR2gzBufrepmYWOBJg Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10727"; a="383666371" X-IronPort-AV: E=Sophos;i="6.00,207,1681196400"; d="scan'208";a="383666371" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2023 16:56:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10727"; a="796910857" X-IronPort-AV: E=Sophos;i="6.00,207,1681196400"; d="scan'208";a="796910857" Received: from orsosgc001.jf.intel.com ([10.165.21.138]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2023 16:56:38 -0700 From: Umesh Nerlige Ramappa To: intel-gfx@lists.freedesktop.org Date: Wed, 31 May 2023 16:56:34 -0700 Message-Id: <20230531235634.1309525-4-umesh.nerlige.ramappa@intel.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20230531235634.1309525-1-umesh.nerlige.ramappa@intel.com> References: <20230531235634.1309525-1-umesh.nerlige.ramappa@intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 3/3] i915/perf: Drop the aged_tail from rewind logic X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lionel G Landwerlin Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Instead of aged_tail use an iterator that starts from the hw_tail and goes backward until the oa_buffer.tail looking for valid reports. Signed-off-by: Umesh Nerlige Ramappa --- drivers/gpu/drm/i915/i915_perf.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c index beb1269422ca..39f5ab1911c8 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -543,7 +543,7 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream) { u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma); int report_size = stream->oa_buffer.format->size; - u32 head, tail, aged_tail; + u32 head, tail, iter; unsigned long flags; bool pollin; u32 hw_tail; @@ -567,15 +567,14 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream) /* Subtract partial amount off the tail */ hw_tail = OA_TAKEN(hw_tail, partial_report_size); - /* NB: The head we observe here might effectively be a little * out of date. If a read() is in progress, the head could be * anywhere between this head and stream->oa_buffer.tail. */ head = stream->oa_buffer.head - gtt_offset; - aged_tail = stream->oa_buffer.tail - gtt_offset; + tail = stream->oa_buffer.tail - gtt_offset; - tail = hw_tail; + iter = hw_tail; /* Walk the stream backward until we find a report with report * id and timestmap not at 0. Since the circular buffer pointers @@ -588,23 +587,23 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream) * memory in the order they were written to. * If not : (╯°□°）╯︵ ┻━┻ */ - while (OA_TAKEN(tail, aged_tail) >= report_size) { - void *report = stream->oa_buffer.vaddr + tail; + while (OA_TAKEN(iter, tail) >= report_size) { + void *report = stream->oa_buffer.vaddr + iter; if (oa_report_id(stream, report) || oa_timestamp(stream, report)) break; - tail = (tail - report_size) & (OA_BUFFER_SIZE - 1); + iter = (iter - report_size) & (OA_BUFFER_SIZE - 1); } - if (OA_TAKEN(hw_tail, tail) > report_size && + if (OA_TAKEN(hw_tail, iter) > report_size && __ratelimit(&stream->perf->tail_pointer_race)) drm_notice(&stream->uncore->i915->drm, "unlanded report(s) head=0x%x tail=0x%x hw_tail=0x%x\n", head, tail, hw_tail); - stream->oa_buffer.tail = gtt_offset + tail; + stream->oa_buffer.tail = gtt_offset + iter; pollin = OA_TAKEN(stream->oa_buffer.tail - gtt_offset, stream->oa_buffer.head - gtt_offset) >= report_size;