From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ms.lwn.net (ms.lwn.net [45.79.88.28]) (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 6470D2CCC1; Thu, 3 Jul 2025 23:47:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.79.88.28 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751586443; cv=none; b=kdpLMulTVyI1qCTnUx/UZw60Znswmif8NktIpfYH7usDG1dV0Ht/h0Ig8gHDVCBkslmq/s8mnnHvxtnj3ORZe3sqw25GFfccMBZBOURRjJl1zjOoX8DuI2ZikbiFdYOtbyUMThKSwBjpen4tHi9B0yLkmK6kxrM0hEfJagdB1Xg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751586443; c=relaxed/simple; bh=VVMkzyjz0mfdIDPozpytox8OIczjDMUbiH5K+U00u1M=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=KHiUafzfuSV8HNO046Ec6rf6y+4CR3HuLthQv3sCZzJFvOX8sAlnmzTQFgwB2CNBGQ1mN0MJvfcrQidU2HTyaG4s3mw2VjCINLsAeYIQAhzIxY3LK0wqPbLvIfISjeyHSfgGRpJsf+RvUyMJaZN3zgZj9Qeo0kUO0cKN2MXmlM0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lwn.net; spf=pass smtp.mailfrom=lwn.net; dkim=pass (2048-bit key) header.d=lwn.net header.i=@lwn.net header.b=bBfXErIA; arc=none smtp.client-ip=45.79.88.28 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lwn.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lwn.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lwn.net header.i=@lwn.net header.b="bBfXErIA" DKIM-Filter: OpenDKIM Filter v2.11.0 ms.lwn.net 99C40406FC DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lwn.net; s=20201203; t=1751586434; bh=jjrkXzfZ3M2tWF+2Oo3lVlQVLY411HZ2WGPa1DpPJ4Q=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=bBfXErIALEsWbKqJY52UF/5viTiHwIaTT7ueLe6Qhlt02Fwp8U0CoE1aZHQ1bHUSV +zTj7Nm6lch/zRqKwgzxrXbL3pttYykHK5aYYEGEh6hOEAybBKbvUV3vSby+RPPz89 5KJmUY0xPEVRqDbjIEAzmtGxWaLrG/acNuK27Rd1OiLOD9XtEWhNVDF2tanYRBhQet gRgvaLHd7iIEWW7omW9Uft8PrMdirPbkf3I+w3PkBJlL8YfFeUn7nm5TyyLPR0vF54 zNuZGY4/lSeltzas281t+4Trr//YjmyRs7e+UbAmBaGQV8nkUPR6SZ88WSrT5hJjD1 STzY5Hq9iQDGg== Received: from localhost (unknown [IPv6:2601:280:4600:2da9::1fe]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id 99C40406FC; Thu, 3 Jul 2025 23:47:14 +0000 (UTC) From: Jonathan Corbet To: Mauro Carvalho Chehab Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Akira Yokosawa Subject: Re: [PATCH v2 2/7] docs: kdoc: micro-optimize KernRe In-Reply-To: <20250704003146.118f5799@foz.lan> References: <20250703184403.274408-1-corbet@lwn.net> <20250703184403.274408-3-corbet@lwn.net> <20250704003146.118f5799@foz.lan> Date: Thu, 03 Jul 2025 17:47:13 -0600 Message-ID: <87ms9kkfb2.fsf@trenco.lwn.net> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Mauro Carvalho Chehab writes: > Em Thu, 3 Jul 2025 12:43:58 -0600 > Jonathan Corbet escreveu: > >> Rework _add_regex() to avoid doing the lookup twice for the (hopefully >> common) cache-hit case. >> >> Signed-off-by: Jonathan Corbet >> --- >> scripts/lib/kdoc/kdoc_re.py | 7 ++----- >> 1 file changed, 2 insertions(+), 5 deletions(-) >> >> diff --git a/scripts/lib/kdoc/kdoc_re.py b/scripts/lib/kdoc/kdoc_re.py >> index e81695b273bf..612223e1e723 100644 >> --- a/scripts/lib/kdoc/kdoc_re.py >> +++ b/scripts/lib/kdoc/kdoc_re.py >> @@ -29,12 +29,9 @@ class KernRe: >> """ >> Adds a new regex or re-use it from the cache. >> """ >> - >> - if string in re_cache: >> - self.regex = re_cache[string] >> - else: >> + self.regex = re_cache.get(string, None) > > With get, None is default... > >> + if not self.regex: >> self.regex = re.compile(string, flags=flags) > > ... yet, as you're using get, better to code it as: > > self.regex = re_cache.get(string, re.compile(string, flags=flags)) ...but that will recompile the regex each time, defeating the purpose of the cache, no? Thanks, jon