From patchwork Thu Mar 13 10:13:49 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: AKASHI Takahiro X-Patchwork-Id: 3825191 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E704BBF540 for ; Thu, 13 Mar 2014 11:31:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id F26AC201CE for ; Thu, 13 Mar 2014 11:30:59 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F3EB8201C7 for ; Thu, 13 Mar 2014 11:30:58 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WO2h1-00032Z-JD; Thu, 13 Mar 2014 10:16:52 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WO2gM-0002w8-W1; Thu, 13 Mar 2014 10:16:11 +0000 Received: from mail-pb0-f42.google.com ([209.85.160.42]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WO2fg-0002nh-VB for linux-arm-kernel@lists.infradead.org; Thu, 13 Mar 2014 10:15:37 +0000 Received: by mail-pb0-f42.google.com with SMTP id rr13so904846pbb.29 for ; Thu, 13 Mar 2014 03:15:07 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=HlHdSBlH/vNsDdDRUEseMekSZ79D9aPJ1XLkr0XF7eE=; b=Sju/bghLQC9WxG9txx7JINA2ItbEEIeHaFJBwMcw6Yhd4VVRbZjqurJfUYk1965+8V 4SPnoBPrRUk311ozMH1rHvGlxYgyGqwatI0EKfjYGLZASq/A2DfYE2xpk98YVRLP+aBA WDXq8DkdTGOFHg8JqAcK/Q974jULkQTzYR6HcPDpDKah67SIzy6a+y1oy+P7zYgf/wlU 4L8OTrGUrmDbRpYl2AeC2oglwYTs2/9JhZTyaFD8hFMMBPsm1ISTx3hXrnMapPn/CB23 kCADpz1oQgN5V6hX+SGX9Lpvru1DT+3QvYaVEft6j0M2I5xSUSmbrHD7nG+4AcLjzUu6 hIyg== X-Gm-Message-State: ALoCoQkhjnSYMTM0JerdaaV3mdEu786fEBot5NiJNyTSfyJlQfLf/03VTZhHbih3HAf9Wfq+FImP X-Received: by 10.66.246.229 with SMTP id xz5mr1153059pac.119.1394705707256; Thu, 13 Mar 2014 03:15:07 -0700 (PDT) Received: from localhost.localdomain (KD182249091179.au-net.ne.jp. [182.249.91.179]) by mx.google.com with ESMTPSA id yj1sm7505037pab.30.2014.03.13.03.15.02 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 13 Mar 2014 03:15:06 -0700 (PDT) From: AKASHI Takahiro To: rostedt@goodmis.org, fweisbec@gmail.com, mingo@redhat.com, catalin.marinas@arm.com, will.deacon@arm.com, tim.bird@sonymobile.com Subject: [PATCH v6 6/7] arm64: ftrace: Add CALLER_ADDRx macros Date: Thu, 13 Mar 2014 19:13:49 +0900 Message-Id: <1394705630-12384-7-git-send-email-takahiro.akashi@linaro.org> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1394705630-12384-1-git-send-email-takahiro.akashi@linaro.org> References: <1393564724-3966-1-git-send-email-takahiro.akashi@linaro.org> <1394705630-12384-1-git-send-email-takahiro.akashi@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140313_061529_171461_A4152FA9 X-CRM114-Status: GOOD ( 16.26 ) X-Spam-Score: -2.6 (--) Cc: linaro-kernel@lists.linaro.org, arndb@arndb.de, linux-kernel@vger.kernel.org, AKASHI Takahiro , dsaxena@linaro.org, gkulkarni@caviumnetworks.com, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP CALLER_ADDRx returns caller's address at specified level in call stacks. They are used for several tracers like irqsoff and preemptoff. Strange to say, however, they are refered even without FTRACE. Please note that this implementation assumes that we have frame pointers. (which means kernel should be compiled with -fno-omit-frame-pointer.) Signed-off-by: AKASHI Takahiro --- arch/arm64/include/asm/ftrace.h | 13 ++++++++- arch/arm64/kernel/Makefile | 3 +- arch/arm64/kernel/return_address.c | 55 ++++++++++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+), 2 deletions(-) create mode 100644 arch/arm64/kernel/return_address.c diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index ed5c448..c44c4b1 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -18,6 +18,7 @@ #ifndef __ASSEMBLY__ extern void _mcount(unsigned long); +extern void *return_address(unsigned int); struct dyn_arch_ftrace { /* No extra data needed for arm64 */ @@ -33,6 +34,16 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) */ return addr; } -#endif /* __ASSEMBLY__ */ + +#define HAVE_ARCH_CALLER_ADDR + +#define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) +#define CALLER_ADDR1 ((unsigned long)return_address(1)) +#define CALLER_ADDR2 ((unsigned long)return_address(2)) +#define CALLER_ADDR3 ((unsigned long)return_address(3)) +#define CALLER_ADDR4 ((unsigned long)return_address(4)) +#define CALLER_ADDR5 ((unsigned long)return_address(5)) +#define CALLER_ADDR6 ((unsigned long)return_address(6)) +#endif /* ifndef __ASSEMBLY__ */ #endif /* __ASM_FTRACE_H */ diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index ac67fd0..b5bfa7f 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -7,12 +7,13 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) CFLAGS_REMOVE_ftrace.o = -pg CFLAGS_REMOVE_insn.o = -pg +CFLAGS_REMOVE_return_address.o = -pg # Object file lists. arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \ entry-fpsimd.o process.o ptrace.o setup.o signal.o \ sys.o stacktrace.o time.o traps.o io.o vdso.o \ - hyp-stub.o psci.o cpu_ops.o insn.o + hyp-stub.o psci.o cpu_ops.o insn.o return_address.o arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \ sys_compat.o diff --git a/arch/arm64/kernel/return_address.c b/arch/arm64/kernel/return_address.c new file mode 100644 index 0000000..89102a6 --- /dev/null +++ b/arch/arm64/kernel/return_address.c @@ -0,0 +1,55 @@ +/* + * arch/arm64/kernel/return_address.c + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include + +#include + +struct return_address_data { + unsigned int level; + void *addr; +}; + +static int save_return_addr(struct stackframe *frame, void *d) +{ + struct return_address_data *data = d; + + if (!data->level) { + data->addr = (void *)frame->pc; + return 1; + } else { + --data->level; + return 0; + } +} + +void *return_address(unsigned int level) +{ + struct return_address_data data; + struct stackframe frame; + register unsigned long current_sp asm ("sp"); + + data.level = level + 2; + data.addr = NULL; + + frame.fp = (unsigned long)__builtin_frame_address(0); + frame.sp = current_sp; + frame.pc = (unsigned long)return_address; /* dummy */ + + walk_stackframe(&frame, save_return_addr, &data); + + if (!data.level) + return data.addr; + else + return NULL; +} +EXPORT_SYMBOL_GPL(return_address);