From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753038AbZJZPQT (ORCPT ); Mon, 26 Oct 2009 11:16:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752810AbZJZPQR (ORCPT ); Mon, 26 Oct 2009 11:16:17 -0400 Received: from qw-out-2122.google.com ([74.125.92.24]:4631 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752878AbZJZPQO (ORCPT ); Mon, 26 Oct 2009 11:16:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=oDtdicuJmq4E1RZ6YPTveXqWSdBgB2dcoJs8MVsT44Xo7GmNP/QxAL3MD0F0b9+SxE XWAriSWoWY9sRVIIpW4rXphbwICoxEgVWfErNp3lppU6OKTXtvovjkkrbk6opm8IpExr sFCUvCsWRt1oaMKq3GgBY27AaESBfkT8xFhdc= From: Wu Zhangjin To: linux-mips@linux-mips.org, linux-kernel@vger.kernel.org Cc: Wu Zhangjin , Frederic Weisbecker , rostedt@goodmis.org, Thomas Gleixner , Ralf Baechle , Richard Sandiford , Nicholas Mc Guire , David Daney , Adam Nemet , Patrik Kluba Subject: [PATCH -v6 13/13] tracing: add dynamic function graph tracer for MIPS Date: Mon, 26 Oct 2009 23:13:30 +0800 Message-Id: X-Mailer: git-send-email 1.6.2.1 In-Reply-To: <60dd7085d4df145318582d0a829887b4abf6e6c1.1256569489.git.wuzhangjin@gmail.com> References: <747deea2f18d5ccffe842df95a9dd1c86251a958.1256569489.git.wuzhangjin@gmail.com> <3f47087b70a965fd679b17a59521671296457df1.1256569489.git.wuzhangjin@gmail.com> <07dc907ec62353b1aca99b2850d3b2e4b734189a.1256569489.git.wuzhangjin@gmail.com> <374da7039d2e1b97083edd8bcd7811356884d427.1256569489.git.wuzhangjin@gmail.com> <3c82af564d70be05b92687949ed134ce034bf8db.1256569489.git.wuzhangjin@gmail.com> <07e35715c3af78e3c4b537940277240ed031365a.1256569489.git.wuzhangjin@gmail.com> <4e022c090601c3585a8d69a54deade2a53f93e8c.1256569489.git.wuzhangjin@gmail.com> <60dd7085d4df145318582d0a829887b4abf6e6c1.1256569489.git.wuzhangjin@gmail.com> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch make function graph tracer work with dynamic function tracer. To share the source code of dynamic function tracer(MCOUNT_SAVE_REGS), and avoid restoring the whole saved registers, we need to restore the ra register from the stack. Signed-off-by: Wu Zhangjin --- arch/mips/kernel/ftrace.c | 21 +++++++++++++++++++++ arch/mips/kernel/mcount.S | 14 ++++++++++++-- 2 files changed, 33 insertions(+), 2 deletions(-) diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c index 4cf11f5..1c02e65 100644 --- a/arch/mips/kernel/ftrace.c +++ b/arch/mips/kernel/ftrace.c @@ -79,6 +79,27 @@ int __init ftrace_dyn_arch_init(void *data) #ifdef CONFIG_FUNCTION_GRAPH_TRACER +#ifdef CONFIG_DYNAMIC_FTRACE + +extern void ftrace_graph_call(void); +#define JMP 0x08000000 /* jump to target directly */ +#define CALL_FTRACE_GRAPH_CALLER \ + jump_insn_encode(JMP, (unsigned long)(&ftrace_graph_caller)) +#define FTRACE_GRAPH_CALL_IP ((unsigned long)(&ftrace_graph_call)) + +int ftrace_enable_ftrace_graph_caller(void) +{ + return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, + CALL_FTRACE_GRAPH_CALLER); +} + +int ftrace_disable_ftrace_graph_caller(void) +{ + return ftrace_modify_code(FTRACE_GRAPH_CALL_IP, ftrace_nop); +} + +#endif /* !CONFIG_DYNAMIC_FTRACE */ + #define S_RA (0x2fbf << 16) /* 32bit: afbf, 64bit: ffbf */ #define MOV_FP_SP 0x03a0f021 /* 32bit: 0x03a0f021, 64bit: 0x03a0f02d */ #define STACK_OFFSET_MASK 0xfff /* stack offset range: 0 ~ PT_SIZE(304) */ diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S index a9ba888..260719d 100644 --- a/arch/mips/kernel/mcount.S +++ b/arch/mips/kernel/mcount.S @@ -82,6 +82,13 @@ ftrace_call: nop /* a placeholder for the call to a real tracing function */ nop /* Do not touch me, I'm in the dealy slot of "jal func" */ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + .globl ftrace_graph_call +ftrace_graph_call: + nop + nop +#endif + MCOUNT_RESTORE_REGS .globl ftrace_stub ftrace_stub: @@ -129,10 +136,13 @@ ftrace_stub: #ifdef CONFIG_FUNCTION_GRAPH_TRACER NESTED(ftrace_graph_caller, PT_SIZE, ra) +#ifdef CONFIG_DYNAMIC_FTRACE + PTR_L a1, PT_R31(sp) /* load the original ra from the stack */ +#else MCOUNT_SAVE_REGS - - PTR_LA a0, PT_R1(sp) /* arg1: &AT -> a0 */ move a1, ra /* arg2: next ip, selfaddr */ +#endif + PTR_LA a0, PT_R1(sp) /* arg1: &AT -> a0 */ PTR_SUBU a1, MCOUNT_INSN_SIZE move a2, fp /* arg3: frame pointer */ jal prepare_ftrace_return -- 1.6.2.1