From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1ZMWpH-0002tS-Rw for mharc-qemu-trivial@gnu.org; Tue, 04 Aug 2015 03:39:55 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56420) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZMWpF-0002tJ-Ro for qemu-trivial@nongnu.org; Tue, 04 Aug 2015 03:39:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZMWpA-00005o-Sc for qemu-trivial@nongnu.org; Tue, 04 Aug 2015 03:39:53 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:35107) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZMWpA-00005R-Lz for qemu-trivial@nongnu.org; Tue, 04 Aug 2015 03:39:48 -0400 Received: by wibxm9 with SMTP id xm9so153339293wib.0 for ; Tue, 04 Aug 2015 00:39:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:references:from:to:cc:subject:in-reply-to:date :message-id:mime-version:content-type:content-transfer-encoding; bh=AW5KKGfLlK3G1j4RlJRhY2TjMbDURL9CYwnmFLRe6xw=; b=LUgiBXByjT2d1+rKCT/cQx71EDrmqpoq+6A1GSnhyAdP7lnznZ8EUOLdEvozFjskpd +QqqQiK+e75wm6XL6hLgJ+pD/+GXKvLF+H5ji7cLcUiX3LS26YSki864+FsArxTNedgq FnPhzNs0UDXi2utYeCGwqIJEtI17RL4GMK9arffqycpoSfdkRMYtFSzproQYtrWo1n3G mCgTQbafjRgOHISNk0ZjYU23PIdDvCbUN2UpW7SnVh29PC0YGnRNVXcq8W0R0kxY6wP5 g36Y8+nsdcgg2bWSDd0oGdPzN3teaZB3Ihja97SQAX6IoZmYDOeumF4cybxyiEbz6nQp ws5Q== X-Gm-Message-State: ALoCoQlqRCVcWcZihhLjmnDvWD/79HEWJAGPzCh1Mx0jeT8ftuImKXGMcDrVx8pBia0qho7I2O4h X-Received: by 10.195.11.74 with SMTP id eg10mr4889726wjd.33.1438673987922; Tue, 04 Aug 2015 00:39:47 -0700 (PDT) Received: from zen.linaro.local ([81.128.185.34]) by smtp.gmail.com with ESMTPSA id y13sm328194wjq.26.2015.08.04.00.39.46 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Aug 2015 00:39:47 -0700 (PDT) Received: from zen.linaro.local (localhost [127.0.0.1]) by zen.linaro.local (Postfix) with ESMTPS id E065F3E030B; Tue, 4 Aug 2015 08:39:45 +0100 (BST) References: <1438593291-27109-1-git-send-email-alex.bennee@linaro.org> <1438593291-27109-2-git-send-email-alex.bennee@linaro.org> <55BF6F68.1090103@redhat.com> From: Alex =?utf-8?Q?Benn=C3=A9e?= To: Paolo Bonzini In-reply-to: <55BF6F68.1090103@redhat.com> Date: Tue, 04 Aug 2015 08:39:45 +0100 Message-ID: <87k2tblcxq.fsf@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.85.212.172 Cc: qemu-trivial@nongnu.org, crosthwaitepeter@gmail.com, qemu-devel@nongnu.org, rth@twiddle.net Subject: Re: [Qemu-trivial] [PATCH v4 01/11] tcg: add ability to dump /tmp/perf-.map files X-BeenThere: qemu-trivial@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Aug 2015 07:39:54 -0000 Paolo Bonzini writes: > On 03/08/2015 11:14, Alex Bennée wrote: >> This allows the perf tool to map samples to each individual translation >> block. This could be expanded for user space but currently it gives >> enough information to find any hotblocks by other means. >> >> Signed-off-by: Alex Bennée > > What happens if you encounter a tb_flush? At the point of a tb_flush all bets are off as we will re-generate all the blocks at potentially different locations in the translation buffer. However for most analysis cases you are unlikely to cause the code buffer to overflow. Most other uses of tb_flush are the result debugging. I could add a printf when --perfmap is enabled to flag when a flush happens to signal to the user? I guess some more caveats in the flag description wouldn't hurt. We could consider truncating and re-starting the JIT dump at each flush? > > Paolo -- Alex Bennée