Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753445AbZKTMfr (ORCPT ); Fri, 20 Nov 2009 07:35:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753417AbZKTMfp (ORCPT ); Fri, 20 Nov 2009 07:35:45 -0500 Received: from mail-pz0-f171.google.com ([209.85.222.171]:40938 "EHLO mail-pz0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753268AbZKTMfn (ORCPT ); Fri, 20 Nov 2009 07:35:43 -0500 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=xY1poa0DUINwFN988gtWff8G+Es/tyWhi2nLqlte8/032wyO7fYWVxs0lNz7qkX7O4 M3KygJwadH5hiMq/sH3z0lNVjBEVfTZv8r30qnVWCOTzrYH5pWqSBXoim9+KE2gqpwRt b7+bfmyutzh8jSDkAzdFzNvAQVvdYKfFeCg5M= From: Wu Zhangjin To: Ralf Baechle , rostedt@goodmis.org Cc: Nicholas Mc Guire , zhangfx@lemote.com, Wu Zhangjin , Ingo Molnar , Thomas Gleixner , Frederic Weisbecker , linux-kernel@vger.kernel.org, linux-mips@linux-mips.org Subject: [PATCH v9 07/10] tracing: add dynamic function graph tracer for MIPS Date: Fri, 20 Nov 2009 20:34:35 +0800 Message-Id: X-Mailer: git-send-email 1.6.2.1 In-Reply-To: <2276758e661b2b2362432851003df1d7c99d6cc0.1258719323.git.wuzhangjin@gmail.com> References: <51e30436a435480f1f0dec146a82f2b250900690.1258719323.git.wuzhangjin@gmail.com> <267c0824194b659b46fc038ba43492df30369fec.1258719323.git.wuzhangjin@gmail.com> <6a25a6132d64830bbd7339fe8b3841a51d02ac6d.1258719323.git.wuzhangjin@gmail.com> <2ffd3ecb5f0c96b43150968ce270dee71f6afdb8.1258719323.git.wuzhangjin@gmail.com> <2276758e661b2b2362432851003df1d7c99d6cc0.1258719323.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 Content-Length: 2787 Lines: 90 From: Wu Zhangjin 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. (NOTE: This not work with 32bit! need to ensure why!) 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 65a3f8a..e981a49 100644 --- a/arch/mips/kernel/ftrace.c +++ b/arch/mips/kernel/ftrace.c @@ -115,6 +115,27 @@ 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_SP (0xafbf << 16) /* s{d,w} ra, offset(sp) */ #define S_R_SP (0xafb0 << 16) /* s{d,w} R, offset(sp) */ #define OFFSET_MASK 0xffff /* stack offset range: 0 ~ PT_SIZE */ diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S index b50e38d..98d4690 100644 --- a/arch/mips/kernel/mcount.S +++ b/arch/mips/kernel/mcount.S @@ -77,6 +77,13 @@ ftrace_call: nop /* a placeholder for the call to a real tracing function */ move a1, AT /* arg2: the caller's next ip, parent */ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + .globl ftrace_graph_call +ftrace_graph_call: + nop + nop +#endif + MCOUNT_RESTORE_REGS .globl ftrace_stub ftrace_stub: @@ -124,10 +131,13 @@ 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 */ jal prepare_ftrace_return move a2, fp /* arg3: frame pointer */ -- 1.6.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/