From patchwork Sat Jan 7 13:35:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 13092164 X-Patchwork-Delegate: palmer@dabbelt.com 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 662E1C63797 for ; Sat, 7 Jan 2023 13:36:47 +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=2SEgRQiEA4CYnLPOpK63hkEuGwdV569ZdZTra4cFCr8=; b=DFKD8C0L8cpM+y lxUSlCVWq37YRaxwsXumw8Ilij2HWw1dU2MPahL6Jqv0xMvrVu0NjjF79ur2ItxXP1RBncCiRPI1v fcukxVz4niWQrbF2T5sAWad+hTWLRemmnUcLRnw5J+Q1J5R5ogh8QpWabtku/OUPY6sGgQrpyTvFr 0PWD31BWmUji8dvBVbD+EcPR2pmVBElv+Ih8g5zzCe1rVK3kVcbsB8hjDUoY4svvkzc14friweihO hlib61b8nSox5AfA56WOIRuWYUABZYJNUTSJLcvwBJkt6xgsMZF0Sbz2nu/KcF8BDo9CYyKrBJwK3 f0SwRXgVmYAaJsccfCqQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pE9ND-005Krt-HX; Sat, 07 Jan 2023 13:36:35 +0000 Received: from ams.source.kernel.org ([2604:1380:4601:e00::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pE9Mu-005Khc-Ra for linux-riscv@lists.infradead.org; Sat, 07 Jan 2023 13:36:21 +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 ams.source.kernel.org (Postfix) with ESMTPS id 7F379B80EBF; Sat, 7 Jan 2023 13:36:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 042FFC433D2; Sat, 7 Jan 2023 13:36:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673098574; bh=903dKK56VBWA9nReoduRM1k/JbBxJj/M+VNo1IXCs18=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vCeDk01U0FqRBqslPDJ1SQ6NQa4uGYOkTag44ubpYQCa1M5/91Y/7NwZGvgyKVmj+ fvTB/My9tcVvxKSEu/dlGOvlCSOMNYUpBBS8DVYjAcivpNsD3yXojAk807lM6GoRHE jiWNrcnHhnJFNqL/M8OzR3+VBISLdCFm8/jRtyrtz1IUWsNR+o4x8ieNrxDrvunG8V eYD1HfDROaDLXAA1gzaSmhucnFakUlee8EZaddD+yOJGmlxSmEjXgw5uIrKnXwmx75 FQiUweN27gB52CgLLCOV3ntR339GXBkM37DVlSI/bElfSdCdo2g3D4C+hpbbx00Z1S cKK8y6W5Id/Vw== 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, e.shatokhin@yadro.com, guoren@kernel.org Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Guo Ren Subject: [PATCH -next V6 2/7] riscv: ftrace: Remove wasted nops for !RISCV_ISA_C Date: Sat, 7 Jan 2023 08:35:44 -0500 Message-Id: <20230107133549.4192639-3-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20230107133549.4192639-1-guoren@kernel.org> References: <20230107133549.4192639-1-guoren@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230107_053620_364001_0F1D4190 X-CRM114-Status: UNSURE ( 7.23 ) 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: , 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 12d91b0a73d8..ea5a91da6897 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)