Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753880AbcLFRHe (ORCPT ); Tue, 6 Dec 2016 12:07:34 -0500 Received: from mail-wj0-f195.google.com ([209.85.210.195]:34004 "EHLO mail-wj0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752246AbcLFRHZ (ORCPT ); Tue, 6 Dec 2016 12:07:25 -0500 From: Abel Vesa To: linux@armlinux.org.uk, jpoimboe@redhat.com, jeyu@redhat.com, jikos@kernel.org, mbenes@suse.cz, pmladek@suse.com Cc: rostedt@goodmis.org, mingo@redhat.com, gregkh@linuxfoundation.org, geert+renesas@glider.be, davem@davemloft.net, akpm@linux-foundation.org, emil.l.velikov@gmail.com, mchehab@kernel.org, linux@roeck-us.net, ard.biesheuvel@linaro.org, jens.wiklander@linaro.org, jean-philippe.brucker@arm.com, viro@zeniv.linux.org.uk, stefano.stabellini@eu.citrix.com, chris.brandt@renesas.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, Abel Vesa Subject: [PATCH 4/7] arm: Add ftrace with regs support Date: Tue, 6 Dec 2016 17:06:04 +0000 Message-Id: <1481043967-15602-5-git-send-email-abelvesa@linux.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1481043967-15602-1-git-send-email-abelvesa@linux.com> References: <1481043967-15602-1-git-send-email-abelvesa@linux.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1728 Lines: 78 This adds __ftrace_regs_caller which, unlike __ftrace_caller, adds register saving/restoring and livepatch handling if the pc register gets modified by klp_ftrace_handler. Signed-off-by: Abel Vesa --- arch/arm/kernel/entry-ftrace.S | 49 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/arch/arm/kernel/entry-ftrace.S b/arch/arm/kernel/entry-ftrace.S index c73c403..b6ada5c 100644 --- a/arch/arm/kernel/entry-ftrace.S +++ b/arch/arm/kernel/entry-ftrace.S @@ -92,6 +92,46 @@ 2: mcount_exit .endm +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS + +.macro __ftrace_regs_caller suffix + + stmdb sp!, {r0-r15} + mov r3, sp + + ldr r10, [sp, #60] + + mcount_get_lr r1 @ lr of instrumented func + mcount_adjust_addr r0, lr @ instrumented function + + .globl ftrace_regs_call\suffix +ftrace_regs_call\suffix: + bl ftrace_stub + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + .globl ftrace_regs_graph_call\suffix +ftrace_regs_graph_call\suffix: + mov r0, r0 +#endif +#ifdef CONFIG_LIVEPATCH + ldr r0, [sp, #60] + cmp r0, r10 + beq ftrace_regs_caller_end + ldmia sp!, {r0-r12} + add sp, sp, #8 + ldmia sp!, {r11} + sub sp, r12, #16 + str r11, [sp, #12] + ldmia sp!, {r11, r12, lr, pc} +#endif +ftrace_regs_caller_end\suffix: + ldmia sp!, {r0-r14} + add sp, sp, #4 + mov pc, lr +.endm + +#endif + .macro __ftrace_caller suffix mcount_enter @@ -212,6 +252,15 @@ UNWIND(.fnstart) __ftrace_caller UNWIND(.fnend) ENDPROC(ftrace_caller) + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +ENTRY(ftrace_regs_caller) +UNWIND(.fnstart) + __ftrace_regs_caller +UNWIND(.fnend) +ENDPROC(ftrace_regs_caller) +#endif + #endif #ifdef CONFIG_FUNCTION_GRAPH_TRACER -- 2.7.4