From patchwork Thu Mar 14 00:20:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Helen Mae Koike Fornazier X-Patchwork-Id: 10852045 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 7992614DE for ; Thu, 14 Mar 2019 00:21:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5C7832A0AC for ; Thu, 14 Mar 2019 00:21:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 595172A0B6; Thu, 14 Mar 2019 00:21:29 +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,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D40962A0B5 for ; Thu, 14 Mar 2019 00:21:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=szUNypHyS28zq+cjY6ioceyXUje+A9uUTQhsh1svYbc=; b=rSno8CFaNfj7e2 OYnmF8Avb4c2whk9WEymlUdvm4x87rY8BzPhsfgqCV3d/UATZaUhB1Hf4D7kg+uGHRCWHoa/AO1S9 sOg6894iamEfDoC0Z79oIJ2x4tag++cRZCSHihaZTSwkRRCeZX1HELGTnixnw13tvTmwoJgw1DT3i 7e2TmxwgeFuHxG4OnSR8wg1/b5kCecZfGQl81fqhRG2AG7p9NPnQoBzXA2BvA5QA3lN0ph2Zuyl6g TDoqwQyjGdGVJhL+4O2u/1ytSK/YtMn1UTedwk7NKhT6i3KuSeyF1IiBl2xXQx5Usqwt2yhKGsMcw SFY2HsF3BRCKUCiNTzFA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h4E7j-0001xL-SX; Thu, 14 Mar 2019 00:21:27 +0000 Received: from bhuna.collabora.co.uk ([2a00:1098:0:82:1000:25:2eeb:e3e3]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h4E7a-0001rb-AY; Thu, 14 Mar 2019 00:21:26 +0000 Received: from localhost.localdomain (unknown [IPv6:2804:431:9719:798c:867b:ebff:fe52:de60]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: koike) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 20519281462; Thu, 14 Mar 2019 00:21:10 +0000 (GMT) From: Helen Koike To: dri-devel@lists.freedesktop.org, nicholas.kazlauskas@amd.com Subject: [PATCH v3 5/5] drm: don't block fb changes for async plane updates Date: Wed, 13 Mar 2019 21:20:26 -0300 Message-Id: <20190314002027.7833-6-helen.koike@collabora.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190314002027.7833-1-helen.koike@collabora.com> References: <20190314002027.7833-1-helen.koike@collabora.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190313_172118_791470_697F169B X-CRM114-Status: GOOD ( 20.72 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?utf-8?q?Heiko_St=C3=BCbner?= , Sean Paul , David Airlie , daniel.vetter@ffwll.ch, linux-kernel@vger.kernel.org, eric@anholt.net, kernel@collabora.com, Maxime Ripard , amd-gfx@lists.freedesktop.org, linux-rockchip@lists.infradead.org, harry.wentland@amd.com, andrey.grodzovsky@amd.com, linux-arm-msm@vger.kernel.org, Maarten Lankhorst , Helen Koike , Sean Paul , linux-arm-kernel@lists.infradead.org, =?utf-8?q?St=C3=A9phane_Marchesin?= , Sandy Huang , stable@vger.kernel.org, Tomasz Figa , robdclark@gmail.com, boris.brezillon@collabora.com, Daniel Vetter , freedreno@lists.freedesktop.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In the case of a normal sync update, the preparation of framebuffers (be it calling drm_atomic_helper_prepare_planes() or doing setups with drm_framebuffer_get()) are performed in the new_state and the respective cleanups are performed in the old_state. In the case of async updates, the preparation is also done in the new_state but the cleanups are done in the new_state (because updates are performed in place, i.e. in the current state). The current code blocks async udpates when the fb is changed, turning async updates into sync updates, slowing down cursor updates and introducing regressions in igt tests with errors of type: "CRITICAL: completed 97 cursor updated in a period of 30 flips, we expect to complete approximately 15360 updates, with the threshold set at 7680" Fb changes in async updates were prevented to avoid the following scenario: - Async update, oldfb = NULL, newfb = fb1, prepare fb1, cleanup fb1 - Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb2 - Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 (wrong) Where we have a single call to prepare fb2 but double cleanup call to fb2. To solve the above problems, instead of blocking async fb changes, we place the old framebuffer in the new_state object, so when the code performs cleanups in the new_state it will cleanup the old_fb and we will have the following scenario instead: - Async update, oldfb = NULL, newfb = fb1, prepare fb1, no cleanup - Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb1 - Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 Where calls to prepare/cleanup are balanced. Cc: # v4.14+ Fixes: 25dc194b34dd ("drm: Block fb changes for async plane updates") Suggested-by: Boris Brezillon Signed-off-by: Helen Koike Reviewed-by: Boris Brezillon Reviewed-by: Nicholas Kazlauskas --- Hello, I added a TODO in drm_atomic_helper_async_commit() regarding doing a full state swap(), Boris and Nicholas, let me know if this is ok and if I can keep your Reviewed-by tags) As mentioned in the cover letter, I tested in almost all platforms with igt plane_cursor_legacy and kms_cursor_legacy and I didn't see any regressions. But I couldn't test on MSM and AMD because I don't have the hardware I would appreciate if anyone could help me testing those. Thanks! Helen Changes in v3: - Add Reviewed-by tags - Add TODO in drm_atomic_helper_async_commit() Changes in v2: - Change the order of the patch in the series, add this as the last one. - Add documentation - s/ballanced/balanced drivers/gpu/drm/drm_atomic_helper.c | 22 ++++++++++++---------- include/drm/drm_modeset_helper_vtables.h | 5 +++++ 2 files changed, 17 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 2453678d1186..de5812c362b5 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1608,15 +1608,6 @@ int drm_atomic_helper_async_check(struct drm_device *dev, old_plane_state->crtc != new_plane_state->crtc) return -EINVAL; - /* - * FIXME: Since prepare_fb and cleanup_fb are always called on - * the new_plane_state for async updates we need to block framebuffer - * changes. This prevents use of a fb that's been cleaned up and - * double cleanups from occuring. - */ - if (old_plane_state->fb != new_plane_state->fb) - return -EINVAL; - funcs = plane->helper_private; if (!funcs->atomic_async_update) return -EINVAL; @@ -1647,6 +1638,8 @@ EXPORT_SYMBOL(drm_atomic_helper_async_check); * drm_atomic_async_check() succeeds. Async commits are not supposed to swap * the states like normal sync commits, but just do in-place changes on the * current state. + * + * TODO: Implement full swap instead of doing in-place changes. */ void drm_atomic_helper_async_commit(struct drm_device *dev, struct drm_atomic_state *state) @@ -1657,6 +1650,9 @@ void drm_atomic_helper_async_commit(struct drm_device *dev, int i; for_each_new_plane_in_state(state, plane, plane_state, i) { + struct drm_framebuffer *new_fb = plane_state->fb; + struct drm_framebuffer *old_fb = plane->state->fb; + funcs = plane->helper_private; funcs->atomic_async_update(plane, plane_state); @@ -1665,11 +1661,17 @@ void drm_atomic_helper_async_commit(struct drm_device *dev, * plane->state in-place, make sure at least common * properties have been properly updated. */ - WARN_ON_ONCE(plane->state->fb != plane_state->fb); + WARN_ON_ONCE(plane->state->fb != new_fb); WARN_ON_ONCE(plane->state->crtc_x != plane_state->crtc_x); WARN_ON_ONCE(plane->state->crtc_y != plane_state->crtc_y); WARN_ON_ONCE(plane->state->src_x != plane_state->src_x); WARN_ON_ONCE(plane->state->src_y != plane_state->src_y); + + /* + * Make sure the FBs have been swapped so that cleanups in the + * new_state performs a cleanup in the old FB. + */ + WARN_ON_ONCE(plane_state->fb != old_fb); } } EXPORT_SYMBOL(drm_atomic_helper_async_commit); diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h index cfb7be40bed7..ce582e8e8f2f 100644 --- a/include/drm/drm_modeset_helper_vtables.h +++ b/include/drm/drm_modeset_helper_vtables.h @@ -1174,6 +1174,11 @@ struct drm_plane_helper_funcs { * current one with the new plane configurations in the new * plane_state. * + * Drivers should also swap the framebuffers between plane state + * and new_state. This is required because prepare and cleanup calls + * are performed on the new_state object, then to cleanup the old + * framebuffer, it needs to be placed inside the new_state object. + * * FIXME: * - It only works for single plane updates * - Async Pageflips are not supported yet