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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 6FAC5C4332F for ; Tue, 29 Nov 2022 03:33:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=hyKHys7CJ+E/XNSeLqo7kUI5lVtm0y8opQTqTckBQcQ=; b=HnmX1QUzGyEV5Z rv4Bp7edD9dxQ3tGHooVT5etV2VRQFM+yOP/AqBa9wDxj/4ac0jsuYeOZGFptNOfDokHVxx2AiCbB X1lV8Detmof9uDjMEYwmlPax3TsxsB4vd4ZeLZCKyKu4cQfXnz6X6bg4Zk7AgvJx/t8W8YXLaF6DX OCi6no7r+svTOEsuzsfF86gOGrBl4ySk9V9ebMzgREfHqywbgHe5I8uz0vT3aVCFvmx6TvzaFPdMW 5v/aHI2IiSRt9YsxlYZIkGPT/IOQa63ZOGvXwJQSmPFySDDlLr9JVLG3gtc2VV5kN8/GB6wCrK+2E fypBAZyL8VcW5g6n3pBA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ozrMf-005jqU-C4; Tue, 29 Nov 2022 03:32:57 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ozrMb-005jnt-UB for linux-riscv@lists.infradead.org; Tue, 29 Nov 2022 03:32:55 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 758D1609FA; Tue, 29 Nov 2022 03:32:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 495BEC433C1; Tue, 29 Nov 2022 03:32:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1669692772; bh=K44IU5zSr+xRSYeCBFFHSvlbL/P6QS9pgaMT4XAkl6o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JfE3oA5mgIwqLGrffA4x/XQlpl+PMzc9gjYvnBjXyuTbiniCSQxD8ob+NUI/DItKL 4+nT8+0XM652AS1VRhoVtKrbHMc9hDpSKtPqzDbWAs2dQCjt6rVDG2cvF7aRXYlL9U CpMmWLe6ojyuppm+G5mt9KY58hJ6m8L25Pxjf4c3x04OSV/+EdltM5R3aC0bbe/5Y2 9trkjq31gePrrBdZBp1yM7xqtb6+byICy40k/F1SmgopjOJ2D9Ql6etifZF4NHV9S0 Uk3o/IcOnOyrKrTO0OhuETVa9jTV/BJgI+YgK8IBrj1yJVqqlwFE3prSKcRXKxegsG DOvKxUlXS3ZlQ== From: guoren@kernel.org To: anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, conor.dooley@microchip.com, heiko@sntech.de, rostedt@goodmis.org, mhiramat@kernel.org, jolsa@redhat.com, bp@suse.de, jpoimboe@kernel.org, suagrfillet@gmail.com, andy.chiu@sifive.com, mark.rutland@arm.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Guo Ren , Guo Ren Subject: [PATCH V4 2/7] riscv: ftrace: Remove wasted nops for !RISCV_ISA_C Date: Mon, 28 Nov 2022 22:32:25 -0500 Message-Id: <20221129033230.255947-3-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20221129033230.255947-1-guoren@kernel.org> References: <20221129033230.255947-1-guoren@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221128_193254_047533_3A1DDD6E X-CRM114-Status: UNSURE ( 8.06 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Guo Ren When CONFIG_RISCV_ISA_C=n, -fpatchable-function-entry=8 would generate more nops than we expect. Because it treat nop opcode as 0x00000013 instead of 0x0001. Dump of assembler code for function dw_pcie_free_msi: 0xffffffff806fce94 <+0>: sd ra,-8(sp) 0xffffffff806fce98 <+4>: auipc ra,0xff90f 0xffffffff806fce9c <+8>: jalr -684(ra) # 0xffffffff8000bbec 0xffffffff806fcea0 <+12>: ld ra,-8(sp) 0xffffffff806fcea4 <+16>: nop /* wasted */ 0xffffffff806fcea8 <+20>: nop /* wasted */ 0xffffffff806fceac <+24>: nop /* wasted */ 0xffffffff806fceb0 <+28>: nop /* wasted */ 0xffffffff806fceb4 <+0>: addi sp,sp,-48 0xffffffff806fceb8 <+4>: sd s0,32(sp) 0xffffffff806fcebc <+8>: sd s1,24(sp) 0xffffffff806fcec0 <+12>: sd s2,16(sp) 0xffffffff806fcec4 <+16>: sd s3,8(sp) 0xffffffff806fcec8 <+20>: sd ra,40(sp) 0xffffffff806fcecc <+24>: addi s0,sp,48 Signed-off-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 1c8ec656e916..36cc609c5d03 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -11,7 +11,11 @@ LDFLAGS_vmlinux := ifeq ($(CONFIG_DYNAMIC_FTRACE),y) LDFLAGS_vmlinux := --no-relax KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY +ifeq ($(CONFIG_RISCV_ISA_C),y) CC_FLAGS_FTRACE := -fpatchable-function-entry=8 +else + CC_FLAGS_FTRACE := -fpatchable-function-entry=4 +endif endif ifeq ($(CONFIG_CMODEL_MEDLOW),y) -- 2.36.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv