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=2.7 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 B046CC433E0 for ; Mon, 25 May 2020 22:05:53 +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 800482071A for ; Mon, 25 May 2020 22:05:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="R7jOYQMU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 800482071A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=amd-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2F3C289AC0; Mon, 25 May 2020 22:05:53 +0000 (UTC) Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6CF6F89AC3 for ; Mon, 25 May 2020 22:05:51 +0000 (UTC) Received: by mail-pj1-x1030.google.com with SMTP id ci21so373610pjb.3 for ; Mon, 25 May 2020 15:05:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=a7nf/8KpSpgmSY+VEGWjll96CuPv2tIf39JemHACZ0c=; b=R7jOYQMUm/sKEiI6IqNdcx2+4tusVbfPnaK/UXgZQ7F3AvDBAXH8bE7SPPxpQjNma3 OKTqfejVGyMCmi8U69CmwpZkMOUUitly1uerf+K9RVGYeRKK8Ho7ahFSqFLT5pf2h1LD LmlMVSxJQXD70r12RchgVudvpkMQ0RxwehIJBR8MoAK2olkd4mY2jD2oHD2fiRF0GdON V4sN/rDPHayR+LXn7oS50o1nxWzKy5m0NltA+2anZeMT+3iNnuXUgBCz3lGEnLbb4z92 5Dz783FTAUBcTQi/6wK0aCv1nMKrK8gD7U7IH4QhWDnKDaeS4r98ZlyjoWed5z4ExisL d21A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=a7nf/8KpSpgmSY+VEGWjll96CuPv2tIf39JemHACZ0c=; b=Z5jIWwOk0zTwjRnThNQX7Tg4tD4JJTFghgkUHul14dK64l57yvXpOv9jJcwRu4kauy SYWGMcHiD3wMaFcAzqGm89o6e0ZmvThBddvxAArE29RWkFQIXkxi+wmNzhSdkKW9d79i WZASA6Qu5Ur6w0kZRx3RbSqXJdHvsQREqR8KTGG+qil+yFGQqdq59LjpJzkZBSSHzCCL W2BwwhQXkCUBU6TjXtcyPmGGK2Dhn6tKFUv8jNwzMBur+ZhYId+qEusaU1mvnEXlrQt4 vs4RzjeYI7dPfdbhdlie+PG/YEnHKec1u1Y+iA/K+DvXFmbPMGcE/USfF7NunN3apGz5 bNFA== X-Gm-Message-State: AOAM533BBunspWFe4YQSZYnPBfV76vronpFaSuHmySv835Blve3pTEOQ jn9XkUyWkH9r4bfrlPCWzIv/laYiVPucKbTd7/sXbQ== X-Google-Smtp-Source: ABdhPJzNLrrHx52riKKrEwR5aaYjAJwZnw0m7N9rmzPmnoP7NDRGphBFzcQf+lezAPgx5N4e2afjqMTzDjh7TiusxpU= X-Received: by 2002:a17:902:9007:: with SMTP id a7mr31408186plp.194.1590444350698; Mon, 25 May 2020 15:05:50 -0700 (PDT) MIME-Version: 1.0 From: =?UTF-8?B?TWFyZWsgT2zFocOhaw==?= Date: Mon, 25 May 2020 18:05:14 -0400 Message-ID: Subject: amdgpu doesn't do implicit sync, requires drivers to do it in IBs To: amd-gfx mailing list , Bas Nieuwenhuizen , =?UTF-8?Q?Michel_D=C3=A4nzer?= , =?UTF-8?Q?Christian_K=C3=B6nig?= X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============0422685183==" Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" --===============0422685183== Content-Type: multipart/alternative; boundary="0000000000008ef8c905a6802eb9" --0000000000008ef8c905a6802eb9 Content-Type: text/plain; charset="UTF-8" Hi Christian, Bas and Michel wanted to discuss this. The main disadvantage of no implicit (pipeline) sync within the same queue is that we get lower performance and lower GPU utilization in some cases. We actually never really needed the kernel to have implicit sync, because all user mode drivers contained hacks to work without it. Marek --0000000000008ef8c905a6802eb9 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Christian,

Bas and Michel= wanted to discuss this. The main disadvantage of no implicit (pipeline) sy= nc within the same queue is that we get lower performance and lower GPU uti= lization in some cases.

We actually never real= ly needed the kernel to have implicit sync, because all user mode drivers c= ontained hacks to work without it.

Marek
=
--0000000000008ef8c905a6802eb9-- --===============0422685183== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx --===============0422685183==--