From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 252AFC388F7 for ; Sun, 25 Oct 2020 18:28:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D8EF822269 for ; Sun, 25 Oct 2020 18:28:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1418072AbgJYS2F (ORCPT ); Sun, 25 Oct 2020 14:28:05 -0400 Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:57034 "EHLO mail3-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732784AbgJYS2E (ORCPT ); Sun, 25 Oct 2020 14:28:04 -0400 X-IronPort-AV: E=Sophos;i="5.77,416,1596492000"; d="scan'208";a="362719074" Received: from 173.121.68.85.rev.sfr.net (HELO hadrien) ([85.68.121.173]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Oct 2020 19:28:02 +0100 Date: Sun, 25 Oct 2020 19:28:01 +0100 (CET) From: Julia Lawall X-X-Sender: jll@hadrien To: Markus Elfring cc: Coccinelle , Gilles Muller , Michal Marek , Nicolas Palix , kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: =?UTF-8?Q?Re=3A_=5BCocci=5D_=5BPATCH=5D_Coccinelle=3A_null=3A_O?= =?UTF-8?Q?ptimise_disjunctions_in_SmPL_script_=E2=80=9Ceno=2Eco?= =?UTF-8?Q?cci=E2=80=9D?= In-Reply-To: <0d1575b0-ab37-663e-2464-278fd76280b5@web.de> Message-ID: References: <0d1575b0-ab37-663e-2464-278fd76280b5@web.de> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="8323329-685740588-1603650482=:2714" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-685740588-1603650482=:2714 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT On Sun, 25 Oct 2020, Markus Elfring wrote: > From: Markus Elfring > Date: Sun, 25 Oct 2020 18:54:36 +0100 > > A disjunction is applied by this script for the semantic patch language. > This construct uses short-circuit evaluation. It has got the consequence > that the last element of the specified condition will only be checked > if all previous parts did not match. Such a technical detail leads to > a recommended ordering of condition parts if you would like to care for > optimal run time characteristics of SmPL code. > > An usage incidence was determined for the specified identifiers in source > files from the software “Linux next-20201023” by another SmPL script. > > See also: > Determination of an usage statistic for memory allocation calls > https://lore.kernel.org/cocci/2774601.u91sIFNy1E@sonne/ > > This analysis result indicates a clear ranking for such function calls. > Thus reorder the SmPL disjunction items according to their usage incidence. Did you actually test this before and after the change and see a difference in performance? On my laptop, I see absolutely no difference, for the patch mode and for the context mode. I didn't try the other cases. Before the change: patch: 440.182u 2.049s 1:53.12 390.9% 0+0k 0+232io 4pf+0w context: 392.931u 2.164s 1:41.53 389.1% 0+0k 432+360io 5pf+0w After the change: patch: 442.182u 2.090s 1:54.13 389.2% 0+0k 0+240io 4pf+0w context: 392.742u 2.035s 1:41.37 389.4% 0+0k 0+360io 4pf+0w julia > > Signed-off-by: Markus Elfring > --- > scripts/coccinelle/null/eno.cocci | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/scripts/coccinelle/null/eno.cocci b/scripts/coccinelle/null/eno.cocci > index 81584ff87956..969cab5116a9 100644 > --- a/scripts/coccinelle/null/eno.cocci > +++ b/scripts/coccinelle/null/eno.cocci > @@ -17,8 +17,16 @@ virtual report > @depends on patch@ > expression x,E; > @@ > - > -x = \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\)(...) > + x = > +(kzalloc > +|kmalloc > +|kcalloc > +|kmem_cache_alloc > +|kmem_cache_zalloc > +|kzalloc_node > +|kmalloc_node > +|kmem_cache_alloc_node > +)(...) > ... when != x = E > - IS_ERR(x) > + !x > @@ -27,8 +35,7 @@ x = \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache > expression x,E; > position p1,p2; > @@ > - > -*x = \(kmalloc@p1\|kzalloc@p1\|kcalloc@p1\|kmem_cache_alloc@p1\|kmem_cache_zalloc@p1\|kmem_cache_alloc_node@p1\|kmalloc_node@p1\|kzalloc_node@p1\)(...) > +*x = \(kzalloc@p1\|kmalloc@p1\|kcalloc@p1\|kmem_cache_alloc@p1\|kmem_cache_zalloc@p1\|kzalloc_node@p1\|kmalloc_node@p1\|kmem_cache_alloc_node@p1\)(...) > ... when != x = E > * IS_ERR@p2(x) > > -- > 2.29.1 > > _______________________________________________ > Cocci mailing list > Cocci@systeme.lip6.fr > https://systeme.lip6.fr/mailman/listinfo/cocci > --8323329-685740588-1603650482=:2714--