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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 937C8CA9EB5 for ; Mon, 4 Nov 2019 13:52:13 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 67A0221929 for ; Mon, 4 Nov 2019 13:52:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="inBk+/WO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 67A0221929 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Fx9nlO4AG6QMg6Bal/bx9vmPiatykYVDKJP+/xCEnok=; b=inBk+/WOaCZFZm H5gFPqfdgYpvftZeD9ztuKyVXGR0u9/WNgx9N8abIq+NnB091U7tS0YBsheDNBC6uUK6WuaRvun4n WgY5LwMdX8/Wg6ks4ZejbK67cobIpKH15FjvG3Jr2yr5m95NQSsLD9bKCBN+AWXHMSjSOyFpLoCAw SdHtBWqe6kLuqM42h/R9bRxMga2fdTzZ0qFNS3cVMNc9xwS+nTb4WGBRJCyqzPniRwGnkUabWiAmp IZ8QKOqON4EHPhDm8Mo/9MKN8dgz1UXmGCC1YncTiv5vK72A+JdQAqLXQ9Rgqz/GnRMoXldFJIzub L6xjjG77S6dsA72Eq/yQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iRcm6-0001GC-EP; Mon, 04 Nov 2019 13:52:06 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iRcm3-0001FH-9g for linux-arm-kernel@lists.infradead.org; Mon, 04 Nov 2019 13:52:04 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C5F171FB; Mon, 4 Nov 2019 05:52:00 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 739A93F6C4; Mon, 4 Nov 2019 05:51:58 -0800 (PST) Date: Mon, 4 Nov 2019 13:51:56 +0000 From: Mark Rutland To: Amit Daniel Kachhap Subject: Re: [PATCHv2 7/8] arm64: implement ftrace with regs Message-ID: <20191104135155.GG45140@lakrids.cambridge.arm.com> References: <20191029165832.33606-1-mark.rutland@arm.com> <20191029165832.33606-8-mark.rutland@arm.com> <8132dc13-9fbd-24e2-8a5e-28b005043c3e@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <8132dc13-9fbd-24e2-8a5e-28b005043c3e@arm.com> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191104_055203_379621_F3D7EB6B X-CRM114-Status: GOOD ( 10.20 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jthierry@redhat.com, linux-parisc@vger.kernel.org, peterz@infradead.org, catalin.marinas@arm.com, deller@gmx.de, jpoimboe@redhat.com, linux-kernel@vger.kernel.org, rostedt@goodmis.org, James.Bottomley@HansenPartnership.com, takahiro.akashi@linaro.org, will@kernel.org, mingo@redhat.com, james.morse@arm.com, jeyu@kernel.org, Torsten Duwe , svens@stackframe.org, duwe@suse.de, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, Nov 02, 2019 at 05:51:46PM +0530, Amit Daniel Kachhap wrote: > On 10/29/19 10:28 PM, Mark Rutland wrote: > > +/* > > + * Due to -fpatchable-function-entry=2, the compiler has placed two NOPs before > > + * the regular function prologue. For an enabled callsite, ftrace_init_nop() and > > + * ftrace_make_call() have patched those NOPs to: > > + * > > + * MOV X9, LR > > + * BL > > + * > > + * ... where is either ftrace_caller or ftrace_regs_caller. > > + * > > + * Each instrumented function follows the AAPCS, so here x0-x8 and x19-x30 are > > + * live, and x9-x18 are safe to clobber. > > + * > > + * We save the callsite's context into a pt_regs before invoking and ftrace > s/invoking and ftrace callbacks/invoking the ftrace callbacks Whoops, that was meant to be 'any'. I've fixed that up locally. Thanks, Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel