From patchwork Fri Aug 12 06:25:14 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: akash.goel@intel.com X-Patchwork-Id: 9276381 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 84DBF600CB for ; Fri, 12 Aug 2016 06:12:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 768D72888A for ; Fri, 12 Aug 2016 06:12:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6B5782888C; Fri, 12 Aug 2016 06:12:04 +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 1B2AD2888B for ; Fri, 12 Aug 2016 06:12:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 945466EA6C; Fri, 12 Aug 2016 06:12:03 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTP id 6AA9E6EA67 for ; Fri, 12 Aug 2016 06:12:02 +0000 (UTC) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga102.jf.intel.com with ESMTP; 11 Aug 2016 23:12:03 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,508,1464678000"; d="scan'208";a="154643664" Received: from akashgoe-desktop.iind.intel.com ([10.223.82.36]) by fmsmga004.fm.intel.com with ESMTP; 11 Aug 2016 23:12:01 -0700 From: akash.goel@intel.com To: intel-gfx@lists.freedesktop.org Date: Fri, 12 Aug 2016 11:55:14 +0530 Message-Id: <1470983123-22127-12-git-send-email-akash.goel@intel.com> X-Mailer: git-send-email 1.9.2 In-Reply-To: <1470983123-22127-1-git-send-email-akash.goel@intel.com> References: <1470983123-22127-1-git-send-email-akash.goel@intel.com> Cc: Akash Goel Subject: [Intel-gfx] [PATCH 11/20] drm/i915: Optimization to reduce the sampling time of GuC log buffer 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: Akash Goel GuC firmware sends an interrupt to flush the log buffer when it becomes half full, so Driver doesn't really need to sample the complete buffer and can just copy only the newly written data by GuC into the local buffer, i.e. as per the read & write pointer values. Moreover the flush interrupt would generally come for one type of log buffer, when it becomes half full, so at that time the other 2 types of log buffer would comparatively have much lesser unread data in them. In case of overflow reported by GuC, Driver do need to copy the entire buffer as the whole buffer would contain the unread data. v2: Rebase. Signed-off-by: Akash Goel --- drivers/gpu/drm/i915/i915_guc_submission.c | 40 +++++++++++++++++++++++++----- 1 file changed, 34 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index 1ca1866..8e0f360 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -889,7 +889,8 @@ static void guc_read_update_log_buffer(struct intel_guc *guc) struct guc_log_buffer_state *log_buffer_state, *log_buffer_snapshot_state; struct guc_log_buffer_state log_buffer_state_local; void *src_data_ptr, *dst_data_ptr; - u32 i, buffer_size; + bool new_overflow; + u32 i, buffer_size, read_offset, write_offset, bytes_to_copy; if (!guc->log.buf_addr) return; @@ -912,10 +913,13 @@ static void guc_read_update_log_buffer(struct intel_guc *guc) memcpy(&log_buffer_state_local, log_buffer_state, sizeof(struct guc_log_buffer_state)); buffer_size = log_buffer_state_local.size; + read_offset = log_buffer_state_local.read_ptr; + write_offset = log_buffer_state_local.sampled_write_ptr; guc->log.flush_count[i] += log_buffer_state_local.flush_to_file; if (log_buffer_state_local.buffer_full_cnt != guc->log.prev_overflow_count[i]) { + new_overflow = 1; guc->log.total_overflow_count[i] += (log_buffer_state_local.buffer_full_cnt - guc->log.prev_overflow_count[i]); @@ -929,7 +933,8 @@ static void guc_read_update_log_buffer(struct intel_guc *guc) guc->log.prev_overflow_count[i] = log_buffer_state_local.buffer_full_cnt; DRM_ERROR_RATELIMITED("GuC log buffer overflow\n"); - } + } else + new_overflow = 0; if (log_buffer_snapshot_state) { /* First copy the state structure in local buffer */ @@ -941,13 +946,37 @@ static void guc_read_update_log_buffer(struct intel_guc *guc) * for consistency set the write pointer value to same * value of sampled_write_ptr in the snapshot buffer. */ - log_buffer_snapshot_state->write_ptr = - log_buffer_snapshot_state->sampled_write_ptr; + log_buffer_snapshot_state->write_ptr = write_offset; log_buffer_snapshot_state++; /* Now copy the actual logs */ memcpy(dst_data_ptr, src_data_ptr, buffer_size); + if (unlikely(new_overflow)) { + /* copy the whole buffer in case of overflow */ + read_offset = 0; + write_offset = buffer_size; + } else if (unlikely((read_offset > buffer_size) || + (write_offset > buffer_size))) { + DRM_ERROR("invalid log buffer state\n"); + /* copy whole buffer as offsets are unreliable */ + read_offset = 0; + write_offset = buffer_size; + } + + /* Just copy the newly written data */ + if (read_offset <= write_offset) { + bytes_to_copy = write_offset - read_offset; + memcpy(dst_data_ptr + read_offset, + src_data_ptr + read_offset, bytes_to_copy); + } else { + bytes_to_copy = buffer_size - read_offset; + memcpy(dst_data_ptr + read_offset, + src_data_ptr + read_offset, bytes_to_copy); + + bytes_to_copy = write_offset; + memcpy(dst_data_ptr, src_data_ptr, bytes_to_copy); + } src_data_ptr += buffer_size; dst_data_ptr += buffer_size; @@ -956,8 +985,7 @@ static void guc_read_update_log_buffer(struct intel_guc *guc) /* FIXME: invalidate/flush for log buffer needed */ /* Update the read pointer in the shared log buffer */ - log_buffer_state->read_ptr = - log_buffer_state_local.sampled_write_ptr; + log_buffer_state->read_ptr = write_offset; /* Clear the 'flush to file' flag */ log_buffer_state->flush_to_file = 0;