From patchwork Mon Nov 14 11:28:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 625071 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16878C433FE for ; Mon, 14 Nov 2022 11:29:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236211AbiKNL3O (ORCPT ); Mon, 14 Nov 2022 06:29:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235709AbiKNL2p (ORCPT ); Mon, 14 Nov 2022 06:28:45 -0500 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 099E922F; Mon, 14 Nov 2022 03:28:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1668425303; x=1699961303; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=gR6BZJ2tZuQtMsb7/ERq8PsqpuT7Uc3t1sGvFFJF/U0=; b=IU24lA4i6wHniVfKS1NCOlv0T6fw25/avpuwt+CYLSfS6czNFQFTyeIL aQqM1l8dhVGCgZ/LMC9JrHVirIsjs2ZLMSpHT9fGyxGxWqDAX/36wup2X UXP4rLylsR4fpVhh4mDjaEYAJezLPmcDHx8TeN+6OdKFB775AAuQBBZe1 FlgoKAEgciQmU6+lBYcAE7trLi/PxH+vJpP6VKpC3i6cY6kqWtNe8NOH/ 6eS+Jt7LudF60cJqj/cOv1abJuQNYU0S7edSCDc2ufM2KpLYkle82MeK5 FpLU1oZGhyI1n1OgfwqZe+8KDJQulgcW7Xw0S8U3oPSxFwHfoph14v/Cp g==; X-IronPort-AV: E=McAfee;i="6500,9779,10530"; a="292344098" X-IronPort-AV: E=Sophos;i="5.96,161,1665471600"; d="scan'208";a="292344098" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Nov 2022 03:28:22 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10530"; a="589332578" X-IronPort-AV: E=Sophos;i="5.96,161,1665471600"; d="scan'208";a="589332578" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga003.jf.intel.com with ESMTP; 14 Nov 2022 03:28:19 -0800 Received: by black.fi.intel.com (Postfix, from userid 1003) id 2587D32E; Mon, 14 Nov 2022 13:28:43 +0200 (EET) From: Andy Shevchenko To: Jakob Koschel , Andy Shevchenko , Greg Kroah-Hartman , Mathias Nyman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Kevin Cernekee , Mathias Nyman , Andrew Morton Subject: [PATCH v1 1/4] list: Introduce list_count() to count existing nodes Date: Mon, 14 Nov 2022 13:28:39 +0200 Message-Id: <20221114112842.38565-1-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Some of the existing users, and definitely will be new ones, want to count existing nodes in the list. Provide a generic API for that. Signed-off-by: Andy Shevchenko --- include/linux/list.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/include/linux/list.h b/include/linux/list.h index 61762054b4be..098eccf8c1b6 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -655,6 +655,19 @@ static inline void list_splice_tail_init(struct list_head *list, !list_is_head(pos, (head)); \ pos = n, n = pos->prev) +/** + * list_count - count nodes in the list + * @head: the head for your list. + */ +#define list_count(head) \ +({ \ + struct list_head *__tmp; \ + size_t __i = 0; \ + list_for_each(__tmp, head) \ + __i++; \ + __i; \ +}) + /** * list_entry_is_head - test if the entry points to the head of the list * @pos: the type * to cursor