From patchwork Tue Nov 20 23:12:20 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephen Warren X-Patchwork-Id: 1776561 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id 1CCF63FCAE for ; Tue, 20 Nov 2012 23:14:51 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1Tawzf-00061h-QK; Tue, 20 Nov 2012 23:12:39 +0000 Received: from avon.wwwdotorg.org ([2001:470:1f0f:bd7::2]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1Tawzb-000612-Ke for linux-arm-kernel@lists.infradead.org; Tue, 20 Nov 2012 23:12:36 +0000 Received: from severn.wwwdotorg.org (unknown [192.168.65.5]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by avon.wwwdotorg.org (Postfix) with ESMTPS id 30D7B6254; Tue, 20 Nov 2012 16:14:06 -0700 (MST) Received: from swarren-lx1.nvidia.com (localhost [127.0.0.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by severn.wwwdotorg.org (Postfix) with ESMTPSA id 121D5E40FD; Tue, 20 Nov 2012 16:12:30 -0700 (MST) From: Stephen Warren To: Stephen Warren , John Stultz , Thomas Gleixner , Grant Likely , Rob Herring Subject: [PATCH V4 1/3] of: introduce for_each_matching_node_and_match() Date: Tue, 20 Nov 2012 16:12:20 -0700 Message-Id: <1353453142-4973-1-git-send-email-swarren@wwwdotorg.org> X-Mailer: git-send-email 1.7.10.4 X-NVConfidentiality: public X-Virus-Scanned: clamav-milter 0.96.5 at avon.wwwdotorg.org X-Virus-Status: Clean X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20121120_181235_865620_B7FBA797 X-CRM114-Status: GOOD ( 17.55 ) X-Spam-Score: 0.4 (/) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (0.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- 3.0 KHOP_BIG_TO_CC Sent to 10+ recipients instaed of Bcc or a list -0.0 SPF_PASS SPF: sender matches SPF record -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Thomas Petazzoni , Josh Cartwright , Stephen Warren , Arnd Bergmann , linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org, Olof Johansson , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Stephen Warren The following pattern of code is tempting: for_each_matching_node(np, table) { match = of_match_node(table, np); However, this results in iterating over table twice; the second time inside of_match_node(). The implementation of for_each_matching_node() already found the match, so this is redundant. Invent new function of_find_matching_node_and_match() and macro for_each_matching_node_and_match() to remove the double iteration, thus transforming the above code to: for_each_matching_node_and_match(np, table, &match) Signed-off-by: Stephen Warren --- v4: New patch. This series is based on the ARM sys_timer rework that I posted yesterday, although patch 1/3 should be completely independant of that, and could perhaps even be applied for 3.8 right now. I hope that these patches can be taken through arm-soc tree for 3.9; I will repost them based on 3.8-rc1 at the appropriate time. --- drivers/of/base.c | 18 +++++++++++++----- include/linux/of.h | 15 +++++++++++++-- 2 files changed, 26 insertions(+), 7 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index f2f63c8..094271e 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -594,27 +594,35 @@ const struct of_device_id *of_match_node(const struct of_device_id *matches, EXPORT_SYMBOL(of_match_node); /** - * of_find_matching_node - Find a node based on an of_device_id match - * table. + * of_find_matching_node_and_match - Find a node based on an of_device_id + * match table. * @from: The node to start searching from or NULL, the node * you pass will not be searched, only the next one * will; typically, you pass what the previous call * returned. of_node_put() will be called on it * @matches: array of of device match structures to search in + * @match Updated to point at the matches entry which matched * * Returns a node pointer with refcount incremented, use * of_node_put() on it when done. */ -struct device_node *of_find_matching_node(struct device_node *from, - const struct of_device_id *matches) +struct device_node *of_find_matching_node_and_match(struct device_node *from, + const struct of_device_id *matches, + const struct of_device_id **match) { struct device_node *np; + if (match) + *match = NULL; + read_lock(&devtree_lock); np = from ? from->allnext : allnodes; for (; np; np = np->allnext) { - if (of_match_node(matches, np) && of_node_get(np)) + if (of_match_node(matches, np) && of_node_get(np)) { + if (match) + *match = matches; break; + } } of_node_put(from); read_unlock(&devtree_lock); diff --git a/include/linux/of.h b/include/linux/of.h index 681a6c8..1000496 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -180,11 +180,22 @@ extern struct device_node *of_find_compatible_node(struct device_node *from, #define for_each_compatible_node(dn, type, compatible) \ for (dn = of_find_compatible_node(NULL, type, compatible); dn; \ dn = of_find_compatible_node(dn, type, compatible)) -extern struct device_node *of_find_matching_node(struct device_node *from, - const struct of_device_id *matches); +extern struct device_node *of_find_matching_node_and_match( + struct device_node *from, + const struct of_device_id *matches, + const struct of_device_id **match); +static inline struct device_node *of_find_matching_node( + struct device_node *from, + const struct of_device_id *matches) +{ + return of_find_matching_node_and_match(from, matches, NULL); +} #define for_each_matching_node(dn, matches) \ for (dn = of_find_matching_node(NULL, matches); dn; \ dn = of_find_matching_node(dn, matches)) +#define for_each_matching_node_and_match(dn, matches, match) \ + for (dn = of_find_matching_node_and_match(NULL, matches, match); \ + dn; dn = of_find_matching_node_and_match(dn, matches, match)) extern struct device_node *of_find_node_by_path(const char *path); extern struct device_node *of_find_node_by_phandle(phandle handle); extern struct device_node *of_get_parent(const struct device_node *node);