From patchwork Fri Oct 18 17:36:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hari Bathini X-Patchwork-Id: 13842146 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2767F205ABD; Fri, 18 Oct 2024 17:37:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729273059; cv=none; b=CWZV9GuY0kHACGBNHEvxzFDcki1ZgWXlYh+e6ji6rbeu9QExE9e8jo+ppxX4IuwsztNv/P3q90FNaBI7J2zmura4yZpn1nxKqBLoR0mi0lMmNYPM+xNs1ey4ITzbsRb6TY9WF7ATIZPsTt76NSFJDkOm4GRHYOvaIPbAQz7w5XA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729273059; c=relaxed/simple; bh=pyOcOewZW72GCD2I5kuNDQxApDbXG+PcKezi1rfVdz4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cmyJruvfenSTusnZHVn0qHx3fWWfx6LR0D7ELy4jpF0r+EmBYERG1PToLFCQe0pEflS+MrnK8JOjhwbXE+0qjsCDSx8IuwgQpU/RlF/QScR0RDUGPfQ4427CmTbfEpP+bNZR4qfcbcy4T5IfJaTjPXoVIsO4ECaURh0jaoQRFhs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=aSh24Clz; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="aSh24Clz" Received: from pps.filterd (m0353729.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49IHQrYd011672; Fri, 18 Oct 2024 17:37:15 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=kAoXvrxFta9cBIVUe DwH1olDJxnj60yFKDI048Sn4vE=; b=aSh24ClzqSeFRfqI4iMdO2OSp/gJ3WkNK H2t/S2sM1SKawEDpqu/ei5+AVBZL8mc4LleG+uYvIcBJI67PwxGB2YQPx+4Sefgo T8G9Qcsm/LOIVZ2OEUqUxS1noCxXHizlKwhKnI0vUgbAcz/2lJw+sFsjrneept5l Cxl42TzCQDK2wsqAp845V5lyAFcI7wkUgFv5NWQWMbqG6ZXaNyaYoboXx6hj03Xe 0QBd6gN3DBRXVpLKWtEHvP6N7nLsMRtYv15CInanyrJ1S1sGLHgulVAQbjY4mkkb vtp17sWi4MG5oTMdMFkKG+W+JM+7fbKs6KjLgytt5RECJ26mpqLvQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 42bhnfbs0x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Oct 2024 17:37:15 +0000 (GMT) Received: from m0353729.ppops.net (m0353729.ppops.net [127.0.0.1]) by pps.reinject (8.18.0.8/8.18.0.8) with ESMTP id 49IHbEv6024049; Fri, 18 Oct 2024 17:37:14 GMT Received: from ppma21.wdc07v.mail.ibm.com (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 42bhnfbs0u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Oct 2024 17:37:14 +0000 (GMT) Received: from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1]) by ppma21.wdc07v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 49IH95ip001991; Fri, 18 Oct 2024 17:37:13 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4284en5yyn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Oct 2024 17:37:13 +0000 Received: from smtpav01.fra02v.mail.ibm.com (smtpav01.fra02v.mail.ibm.com [10.20.54.100]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 49IHb9lW41156892 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Oct 2024 17:37:09 GMT Received: from smtpav01.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1288D2004B; Fri, 18 Oct 2024 17:37:09 +0000 (GMT) Received: from smtpav01.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EAB2C20040; Fri, 18 Oct 2024 17:37:04 +0000 (GMT) Received: from li-bd3f974c-2712-11b2-a85c-df1cec4d728e.ibm.com.com (unknown [9.43.99.188]) by smtpav01.fra02v.mail.ibm.com (Postfix) with ESMTP; Fri, 18 Oct 2024 17:37:04 +0000 (GMT) From: Hari Bathini To: linuxppc-dev , bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Michael Ellerman , "Naveen N. Rao" , Mark Rutland , Daniel Borkmann , Masahiro Yamada , Nicholas Piggin , Alexei Starovoitov , Steven Rostedt , Masami Hiramatsu , Andrii Nakryiko , Christophe Leroy , Vishal Chourasia , Mahesh J Salgaonkar Subject: [PATCH v6 07/17] powerpc/ftrace: Skip instruction patching if the instructions are the same Date: Fri, 18 Oct 2024 23:06:22 +0530 Message-ID: <20241018173632.277333-8-hbathini@linux.ibm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241018173632.277333-1-hbathini@linux.ibm.com> References: <20241018173632.277333-1-hbathini@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: pLH_tCLeB-d7EGxhRNV6m0Obflk3SrZ0 X-Proofpoint-ORIG-GUID: a5alJijILmPcPBO9mi0Vn8IrvN6JHRnS X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_01,2024-10-11_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 suspectscore=0 lowpriorityscore=0 impostorscore=0 mlxlogscore=818 malwarescore=0 bulkscore=0 adultscore=0 spamscore=0 phishscore=0 clxscore=1015 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410180111 From: Naveen N Rao To simplify upcoming changes to ftrace, add a check to skip actual instruction patching if the old and new instructions are the same. We still validate that the instruction is what we expect, but don't actually patch the same instruction again. Signed-off-by: Naveen N Rao --- arch/powerpc/kernel/trace/ftrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index fe0546fbac8e..719517265d39 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -82,7 +82,7 @@ static inline int ftrace_modify_code(unsigned long ip, ppc_inst_t old, ppc_inst_ { int ret = ftrace_validate_inst(ip, old); - if (!ret) + if (!ret && !ppc_inst_equal(old, new)) ret = patch_instruction((u32 *)ip, new); return ret;