From patchwork Wed Oct 30 07:08:40 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hari Bathini X-Patchwork-Id: 13856007 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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 B3DC81DEFD6; Wed, 30 Oct 2024 07:09:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.158.5 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730272197; cv=none; b=ScOpC+NptqSjWWmUDOrKU/dG+Jx5E1BdupHg/w042WLQQW08zXw0uOnNdq7O5z1KykH+uhgOXyPF/nhWP2Q50e8Ahp69qBvOWuneaiQFmm2z/s3bOMAOoEg6sAKP2xdH2bkJ7QxwVfZtLar404VyWuI94SvU/b0O3MuMrM4rwb8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730272197; c=relaxed/simple; bh=pyOcOewZW72GCD2I5kuNDQxApDbXG+PcKezi1rfVdz4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ldOVkM0gMAMHRf5P5e5Egd5YiAedgG959g5lbh4KMaFf95LvvOqdwzpadweBL+LoIavwbA5eYRvoa/jn80UB2O6KOlsQj+8T5nNifGQReVwFS2qxsOcbbnsJ6546tikjyiivJCWHoq4QyADkZ+7zlfopCxmX5t62AbV6BL7HNCY= 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=QuIvtXby; arc=none smtp.client-ip=148.163.158.5 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="QuIvtXby" Received: from pps.filterd (m0356516.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49U2d2Q4023917; Wed, 30 Oct 2024 07:09:29 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=QuIvtXbyMWIWcsEgvTxmHCu1+5+hhke5L AgAsKB9Dw4061/KqYpJZeY6XygPUyDq92f4YPvu86pA0LsYud5U9ZRLHfhzQwKsZ EhjmvT1toMxrG48slccDCuDXd4Zr2bz2cO/jvBLlr1gr4+Ti/GoBkICKVn6KOtI9 eg2gIBq+SlEvh3QpjBF8PHIhr+PPByBuGKCx3vYKJHGeul+bNxQAiFwlTj40zeoZ T3Ts5twyH4CckF7P1DevvcNQOVF5KtvKUk8kvwoTlpTxUmpdvplfeaT+Sry4LbhB jjJJmXSuBsFP585Y6SNcyTb00MZqi4z37M1oMCvAqdc/4vm7JXCsw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 42jyhbmb7w-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 30 Oct 2024 07:09:28 +0000 (GMT) Received: from m0356516.ppops.net (m0356516.ppops.net [127.0.0.1]) by pps.reinject (8.18.0.8/8.18.0.8) with ESMTP id 49U79SU9005297; Wed, 30 Oct 2024 07:09:28 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 42jyhbmb7t-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 30 Oct 2024 07:09:28 +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 49U3WkRc013553; Wed, 30 Oct 2024 07:09:27 GMT Received: from smtprelay02.fra02v.mail.ibm.com ([9.218.2.226]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 42hbrmxw5e-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 30 Oct 2024 07:09:27 +0000 Received: from smtpav05.fra02v.mail.ibm.com (smtpav05.fra02v.mail.ibm.com [10.20.54.104]) by smtprelay02.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 49U79N7X57934164 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 30 Oct 2024 07:09:23 GMT Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A948D2004B; Wed, 30 Oct 2024 07:09:23 +0000 (GMT) Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1665720043; Wed, 30 Oct 2024 07:09:20 +0000 (GMT) Received: from li-bd3f974c-2712-11b2-a85c-df1cec4d728e.in.ibm.com (unknown [9.203.115.143]) by smtpav05.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 30 Oct 2024 07:09:19 +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 v7 07/17] powerpc/ftrace: Skip instruction patching if the instructions are the same Date: Wed, 30 Oct 2024 12:38:40 +0530 Message-ID: <20241030070850.1361304-8-hbathini@linux.ibm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241030070850.1361304-1-hbathini@linux.ibm.com> References: <20241030070850.1361304-1-hbathini@linux.ibm.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: GBMiugjyLd0b8gvQjbkREbV1gGerRkzC X-Proofpoint-ORIG-GUID: yeYOmkZEzNvk1I5Zbqc0lKadHVwZSo8P 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 clxscore=1015 mlxscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 lowpriorityscore=0 suspectscore=0 phishscore=0 impostorscore=0 mlxlogscore=816 spamscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410300051 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;