From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31C28C433F5 for ; Fri, 17 Sep 2021 14:50:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 048B760F9C for ; Fri, 17 Sep 2021 14:50:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231626AbhIQOvs (ORCPT ); Fri, 17 Sep 2021 10:51:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234559AbhIQOvm (ORCPT ); Fri, 17 Sep 2021 10:51:42 -0400 Received: from mail-ed1-x532.google.com (mail-ed1-x532.google.com [IPv6:2a00:1450:4864:20::532]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFDB2C061766 for ; Fri, 17 Sep 2021 07:50:20 -0700 (PDT) Received: by mail-ed1-x532.google.com with SMTP id j13so31023651edv.13 for ; Fri, 17 Sep 2021 07:50:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=5RGQxzmlKwLpLejf7DyioqG8/xNm2Xdb7FS3U66xIrQ=; b=KISrc2lSZllL6gBcY+5XK+lD9HLQ+zSIdbbchQVQTKVYPWwYnEjy+hUmPmmIETYGLF uHXfp7iHt4eWj5756feNhEgkLI5RnAYOgGkQY6YIHy39zA7xuIHJnrMN1HGGfkOydDXx ugowRSHA+WDJH+laAfL4w+ShJz/VT+5qy9Ato= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=5RGQxzmlKwLpLejf7DyioqG8/xNm2Xdb7FS3U66xIrQ=; b=45uO6FNtJ9hET83Kzltnb8mMEJHbMtAfWZ0yg7/ura9xWs0xDmdkkP3zNH5tNJgpXz DPzGbgaOMopj4uSkUgxhoV/7MmXuVWvkUJPPKu34r5+bXjOw/OWx9pZldfD2tD7fw06g siNzBSZ0IScHvU6CJpqlBUnbBoF1LyJM+8WAicnkT8Zxv9ewdMZDPi0PJbdvyjkCGDuN +y97YePrXReXbaw28KbCjceVXcaxSnM0WIiCj0veANVYw8H6qKhzN3TCI+YqGW0MbY+n /AUOiJEr0TI0BEqdeP+Liv7Ai/7NQDjWP1v6Txg458amhunPfNqPfV8sI/EvdrTSqwwZ lUeg== X-Gm-Message-State: AOAM530rZQa6gnRNSs5hBD3R5G7+rdRkPEScacHTcQZlf3epWlZg+Y6o xusdWvyylghzEnQ5n83vmdIB6zUYPS7FIA== X-Google-Smtp-Source: ABdhPJxba/NO0TrkGTviWKbmqvAbMZ4UOj73wmiM3lhAiN+9qVsSuL5PWtv7x1Y8+C+2+v3sFyzyhA== X-Received: by 2002:a50:fb06:: with SMTP id d6mr12689369edq.31.1631890219229; Fri, 17 Sep 2021 07:50:19 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id z12sm2718687edx.66.2021.09.17.07.50.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Sep 2021 07:50:18 -0700 (PDT) Date: Fri, 17 Sep 2021 16:50:17 +0200 From: Daniel Vetter To: Christian =?iso-8859-1?Q?K=F6nig?= Cc: linaro-mm-sig@lists.linaro.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, intel-gfx@lists.freedesktop.org, daniel@ffwll.ch Subject: Re: [PATCH 07/26] drm/ttm: use the new iterator in ttm_bo_flush_all_fences Message-ID: References: <20210917123513.1106-1-christian.koenig@amd.com> <20210917123513.1106-8-christian.koenig@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210917123513.1106-8-christian.koenig@amd.com> X-Operating-System: Linux phenom 5.10.0-8-amd64 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Fri, Sep 17, 2021 at 02:34:54PM +0200, Christian König wrote: > This is probably a fix since we didn't even grabed a reference to the > fences. It's rcu protected, and we only care about speeding things up a bit. I think this wont have any impact on correctness, and I don't think any driver could blow up? But yeah maybe we should have a few assert sprinkled into various dma_fence functions to make sure we never call them when the refcount has dropped to 0. That would catch stuff like this, and help lock down the dma-fence api quite a bit. > > Signed-off-by: Christian König > --- > drivers/gpu/drm/ttm/ttm_bo.c | 14 ++++---------- > 1 file changed, 4 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c > index 3b22c0013dbf..7d804c0c69b0 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo.c > +++ b/drivers/gpu/drm/ttm/ttm_bo.c > @@ -269,22 +269,16 @@ static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo) > static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo) > { > struct dma_resv *resv = &bo->base._resv; > - struct dma_resv_list *fobj; > + struct dma_resv_iter cursor; > struct dma_fence *fence; > - int i; > > rcu_read_lock(); > - fobj = dma_resv_shared_list(resv); > - fence = dma_resv_excl_fence(resv); > - if (fence && !fence->ops->signaled) > - dma_fence_enable_sw_signaling(fence); > - > - for (i = 0; fobj && i < fobj->shared_count; ++i) { > - fence = rcu_dereference(fobj->shared[i]); > - > + dma_resv_iter_begin(&cursor, resv, true); > + dma_resv_for_each_fence_unlocked(&cursor, fence) { > if (!fence->ops->signaled) Imo delete this check here. If that really matters for performance we should have it in the core dma_fence function, not replicated all over the place like this. Noodling around in dma_fence internals like this isn't cool. With that removal included: Reviewed-by: Daniel Vetter > dma_fence_enable_sw_signaling(fence); > } > + dma_resv_iter_end(&cursor); > rcu_read_unlock(); > } > > -- > 2.25.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C155CC433F5 for ; Fri, 17 Sep 2021 14:50:22 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 879CE611C3 for ; Fri, 17 Sep 2021 14:50:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 879CE611C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0BF8B6ED29; Fri, 17 Sep 2021 14:50:22 +0000 (UTC) Received: from mail-ed1-x52d.google.com (mail-ed1-x52d.google.com [IPv6:2a00:1450:4864:20::52d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6B5B86ED29 for ; Fri, 17 Sep 2021 14:50:21 +0000 (UTC) Received: by mail-ed1-x52d.google.com with SMTP id v24so30930321eda.3 for ; Fri, 17 Sep 2021 07:50:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=5RGQxzmlKwLpLejf7DyioqG8/xNm2Xdb7FS3U66xIrQ=; b=KISrc2lSZllL6gBcY+5XK+lD9HLQ+zSIdbbchQVQTKVYPWwYnEjy+hUmPmmIETYGLF uHXfp7iHt4eWj5756feNhEgkLI5RnAYOgGkQY6YIHy39zA7xuIHJnrMN1HGGfkOydDXx ugowRSHA+WDJH+laAfL4w+ShJz/VT+5qy9Ato= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=5RGQxzmlKwLpLejf7DyioqG8/xNm2Xdb7FS3U66xIrQ=; b=u7No5Umt07qa8sXNazYVWqu3lstbvZIWHwkopXAG+JO8DA2/oOc0rqxJwH08Pstekz hl57UZDkWzfLLXkeHvU+aKS+2fOBZgKhjEhD9GCQLitt2cyd4Aryhvnu9/P9G1kaU3ZJ 2jUMVQNHJS26hBd7f/aE2JdgI11GY/Z8BTF2nBOqIbdFZw3KnTCTekv7ibhJpKfnjtvm hxFsdjksRGw+4WNjZMxGBv+UbHO05w3E14LPWpmvHN4v9J9ix/g756mDQzmk73tKGVud gUY2djkMmHTpNRM4G8iW+CelfIKdRPBuVYC9A6AuCfDcIgv4R90BwSkpqUoEIgbWUJjG OEFw== X-Gm-Message-State: AOAM530iX+011Sy9lAHIlZPKfVBWQ5SEEQEPA/YlTBKgCqxJHouh8szq 93QTfVysmrR+bGpQFE1+UQ65RA== X-Google-Smtp-Source: ABdhPJxba/NO0TrkGTviWKbmqvAbMZ4UOj73wmiM3lhAiN+9qVsSuL5PWtv7x1Y8+C+2+v3sFyzyhA== X-Received: by 2002:a50:fb06:: with SMTP id d6mr12689369edq.31.1631890219229; Fri, 17 Sep 2021 07:50:19 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id z12sm2718687edx.66.2021.09.17.07.50.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Sep 2021 07:50:18 -0700 (PDT) Date: Fri, 17 Sep 2021 16:50:17 +0200 From: Daniel Vetter To: Christian =?iso-8859-1?Q?K=F6nig?= Cc: linaro-mm-sig@lists.linaro.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, intel-gfx@lists.freedesktop.org, daniel@ffwll.ch Message-ID: References: <20210917123513.1106-1-christian.koenig@amd.com> <20210917123513.1106-8-christian.koenig@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210917123513.1106-8-christian.koenig@amd.com> X-Operating-System: Linux phenom 5.10.0-8-amd64 Subject: Re: [Intel-gfx] [PATCH 07/26] drm/ttm: use the new iterator in ttm_bo_flush_all_fences 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Fri, Sep 17, 2021 at 02:34:54PM +0200, Christian König wrote: > This is probably a fix since we didn't even grabed a reference to the > fences. It's rcu protected, and we only care about speeding things up a bit. I think this wont have any impact on correctness, and I don't think any driver could blow up? But yeah maybe we should have a few assert sprinkled into various dma_fence functions to make sure we never call them when the refcount has dropped to 0. That would catch stuff like this, and help lock down the dma-fence api quite a bit. > > Signed-off-by: Christian König > --- > drivers/gpu/drm/ttm/ttm_bo.c | 14 ++++---------- > 1 file changed, 4 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c > index 3b22c0013dbf..7d804c0c69b0 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo.c > +++ b/drivers/gpu/drm/ttm/ttm_bo.c > @@ -269,22 +269,16 @@ static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo) > static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo) > { > struct dma_resv *resv = &bo->base._resv; > - struct dma_resv_list *fobj; > + struct dma_resv_iter cursor; > struct dma_fence *fence; > - int i; > > rcu_read_lock(); > - fobj = dma_resv_shared_list(resv); > - fence = dma_resv_excl_fence(resv); > - if (fence && !fence->ops->signaled) > - dma_fence_enable_sw_signaling(fence); > - > - for (i = 0; fobj && i < fobj->shared_count; ++i) { > - fence = rcu_dereference(fobj->shared[i]); > - > + dma_resv_iter_begin(&cursor, resv, true); > + dma_resv_for_each_fence_unlocked(&cursor, fence) { > if (!fence->ops->signaled) Imo delete this check here. If that really matters for performance we should have it in the core dma_fence function, not replicated all over the place like this. Noodling around in dma_fence internals like this isn't cool. With that removal included: Reviewed-by: Daniel Vetter > dma_fence_enable_sw_signaling(fence); > } > + dma_resv_iter_end(&cursor); > rcu_read_unlock(); > } > > -- > 2.25.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch