From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgau2.qq.com (smtpbgau2.qq.com [54.206.34.216]) (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 2CDAE3D9020; Mon, 25 May 2026 08:04:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.206.34.216 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779696289; cv=none; b=K2MtstafwGPQHBptyqKU5ro6alw+yEWRpnvGb6e/U4z3K5WeOnh1iBEDEVn3ab1AtxNmACrOpQQAayFs6ER7caeS5pHMvha0Hw6lrSgVEuJenyX2kOJmHDZZk/A9z7JztuwUqLrXILdTCAE+1WaPXPVBbHeNeM3STPdGlenM0Ow= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779696289; c=relaxed/simple; bh=UNF96M+UDCAZMp95O/JWzkeXxV2VuNOkNZ2czONssQM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Tjk5FwI4O1i21idAZxaGi9NfrKAZov4Bxf/BIj8ac3IFU/HH80f5FYnTNtuDC1NWezH8Mxe0nkCPcTx65m+lxCcW38IEX+H9shXT9O81iA1SIKxZdWX9LMqZpTEVrMY0Wkntik7jr+smplKYzav5BEWqFWM3Ahcejizuyv2Oh00= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com; spf=pass smtp.mailfrom=uniontech.com; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b=mhYOt+f5; arc=none smtp.client-ip=54.206.34.216 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=uniontech.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b="mhYOt+f5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=uniontech.com; s=onoh2408; t=1779696249; bh=GK0AcFW5IPbg97vLvTZXdLNFFCxbwYzKywtInr4XSUA=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=mhYOt+f5fQB1YC7zGNhciEa2ldR7+bt7wuCnvO6dxBjRwK12fXVhcV975DWR+WF3Q VPBxeZ7fGtDxVEAduW1JzQrebwRRSWm15uKDpI3N9y+9aZzBUhy8YgtyFcgSSAAQJ/ /KRRmAt2wGVk8/vjLvVuVuUrGgoM5sdiXHAKJxio= X-QQ-mid: esmtpgz16t1779696231t7a118d65 X-QQ-Originating-IP: tglWTa7jp8/hh3inSZB9NJcQwm/bHefu53S7jS2DENM= Received: from localhost.localdomain ( [113.57.152.160]) by bizesmtp.qq.com (ESMTP) with id ; Mon, 25 May 2026 16:03:49 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 1 X-BIZMAIL-ID: 2093867168644187205 EX-QQ-RecipientCnt: 6 From: Wentao Guan To: petr.pavlu@suse.com Cc: guanwentao@uniontech.com, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org, masahiroy@kernel.org Subject: Re: [PATCH v2] genksyms: Support arm64 CRC32 hardware acceleration1~ Date: Mon, 25 May 2026 16:02:29 +0800 Message-Id: <20260525080229.1570905-1-guanwentao@uniontech.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <5d1b8b13-d590-497d-9185-609494135348@suse.com> References: <5d1b8b13-d590-497d-9185-609494135348@suse.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: esmtpgz:uniontech.com:qybglogicsvrgz:qybglogicsvrgz3a-0 X-QQ-XMAILINFO: NWth7vBa++Gd2mL1dw9gWXuxo7KU172DoO2dvIIlgOwnEuR97Z471Sbp ZVkDWcApLRKgCZjPwJ2NgfoY6TT4YJKX3G27zIAqAtrV78OaR9nJEKef1MDjbyQ6f/mncmU 7wJSy2ztJqD5el/i0fPKbAaBgZyuOwqyBc+e6ADXWIfJS+ll61Wh57Za7PvOfvYMebuP3XY bcxffHVQz0z+ImMJTfsbPrG2RsgOTFTVgHaRM7rD8V2z/DhKGnnIohVgcFmwnl64OEYUJ86 21KNY+NPzNk+BOq6V6FSuFCV6LJlVqSoMOBsMu+YT0wWMqycvHBCos83dCP06z99vScwoml h5dAPUARIZMXJbjeComZ1aotfZOaYc2sFa+MQSiN0BccFcbXuEp79rHLaYc9PczDRF8uipu LFGSLQ7hCuwRaOxuFEKaWkRhB2j1eEBGnyVYgPtGLPDQNDTVHLQG2uoAAx18c2iQc+UAGPf CnZ/t+grz3oSCBNlnCRqwhCm/2O8CpZT+1tnXoZDzp8unPjeRCMF42MqXi2+Y3Vo3giN/n7 5QskSAJuzUCxktJ8ByOCNfWAN2n8b/iM54hcMx8pTTbKNEm1PQnDcSWfhGq2dA8JbKU1J4J BXWQM9yFId0dP9FYIYTOaJmUFj0z0NQRCGOvr2T39Pii/95pR1emCN8ms01dHuolKI4I4W3 Yg5e2JUcXEjzGY/+/2fGJkLPPMaaCOxBUwkWrQ+p0FLg99jn8C1/+tS8E/vTYjKkBSaQ263 5WklsxXRvIA+b7txi4azc0lRolm10igHWZxCltXtuvOjUCsS7Zx1eFTpTkMHN4JsXS17f4r XPoGtIuKIzdobV7uC82ikcgOej3wcMvG2MxSPJ/RBI+oiwBdb1Io6kPN6r6xhgAWzoKrj/R sWhFyL1uICo12ZjWkgpcg8nPPBhMxdH3/GHCgH28j8jEVuoQLkLFeezVBKO9C3bchqtO23R 8h4xBF5qUBvno4QKlu0lNz9JhUtNQ+blT89Fav7Sak4O8sG8IAQx0QD9OvW7XVB9ViXAScv serNid8kRf9uQAgjZtXnJNwcx0TI90RIDl+ZAfW6OupS1s/xdgqT5Z9bCyk2Cz0YsNFJJtY g== X-QQ-XMRINFO: Nq+8W0+stu50tPAe92KXseR0ZZmBTk3gLg== X-QQ-RECHKSPAM: 0 Hello Petr, Thanks for your reply, > Could you please provide measurements showing how this improves the > runtime of genksyms and affects the overall kernel build time? Are >From my build kernel workload, genksyms perf report (record -g -F 99) show: without patch: - 7.83% 0.00% genksyms genksyms [.] _start _start - __libc_start_main + 3.19% yylex 1.81% find_symbol 0.92% is_reserved_word 0.62% free_list + 0.56% export_symbol with patch:(find_symbol() and export_symbol() benifit from this): - 7.12% 0.00% genksyms genksyms [.] _start _start - __libc_start_main - 3.01% yylex 0.51% malloc 1.65% find_symbol 0.82% is_reserved_word 0.50% free_list > CRC calculations actually a hot path in genksyms? I don't think it is > worth complicating the genksyms code with architecture-specific > optimizations unless there is a clear benefit. Right. > Additionally, many distributions already switched to gendwarfksyms last > year. Unless someone provides a good reason to keep genksyms around, > I expect it will be deprecated soon and eventually removed. It would be > more valuable to show whether the same optimization is worthwhile for > gendwarfksyms. I see gendwarfksyms use crc32 from , which from zlib1g-dev and zlib1g. BRs Wentao Guan