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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 B77A5C2D0E4 for ; Tue, 17 Nov 2020 11:08:33 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 AED2A207BC for ; Tue, 17 Nov 2020 11:08:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="RC46mI7o" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AED2A207BC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4Cb38Z5Y3tzDqLw for ; Tue, 17 Nov 2020 22:08:30 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Cb34D5wQ7zDqRt for ; Tue, 17 Nov 2020 22:04:44 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ellerman.id.au header.i=@ellerman.id.au header.a=rsa-sha256 header.s=201909 header.b=RC46mI7o; dkim-atps=neutral Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4Cb34D071Tz9sSs; Tue, 17 Nov 2020 22:04:43 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1605611084; bh=F85XDsCUd/+zweu0A2PeEPjjJvwLjHMUUwIvEo61Ovw=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=RC46mI7o9H0+suwlvjg0aJ1MFMrXEHaAGrz54/dbAPDi63Qx4TdDZQhSPQX/cGfXW RWeMFEb7eDuAzqb8yUnFK4Dhz4lqv/Bc3lW+XY/tgoc/6MZ4vBB5Ymw/Fe2+2EV2U+ URJUEayd4sTmKXrhbz9PLSrA9qx9OFWANIou8H+DPVF7/yFrEA33Wv1a7bYS6ElWxn w1zrTFGrknsP7uOlonaojDZscBQgqFeWL7Lv8LLVWBFLG4Spz8Ygcl+7LTd/pmszY5 g2PBDrLeoYZOE9si1Nx5Gq6nCSLQvu++nbSBdbTXep2OTtE2nyDO1xF1yu5Gn43jGr 8G5w51UEnjpSQ== From: Michael Ellerman To: Jordan Niethe Subject: Re: [PATCH] powerpc/powernv/memtrace: Fake non-memblock aligned sized traces In-Reply-To: References: <20201111055524.2458-1-jniethe5@gmail.com> <87blfx4iho.fsf@mpe.ellerman.id.au> Date: Tue, 17 Nov 2020 22:04:43 +1100 Message-ID: <87r1os2qic.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Neuling , linuxppc-dev Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Jordan Niethe writes: > On Mon, Nov 16, 2020 at 11:02 PM Michael Ellerman wrote: >> >> Jordan Niethe writes: >> > The hardware trace macros which use the memory provided by memtrace are >> > able to use trace sizes as small as 16MB. Only memblock aligned values >> > can be removed from each NUMA node by writing that value to >> > memtrace/enable in debugfs. This means setting up, say, a 16MB trace is >> > not possible. To allow such a trace size, instead align whatever value >> > is written to memtrace/enable to the memblock size for the purpose of >> > removing it from each NUMA node but report the written value from >> > memtrace/enable and memtrace/x/size in debugfs. >> >> Why does it matter if the size that's removed is larger than the size >> that was requested? >> >> Is it about constraining the size of the trace? If so that seems like it >> should be the job of the tracing tools, not the kernel. > > Yeah about constraining the size, I'll just do it in the trace tools. OK, I think that would be better. Thanks. cheers