From patchwork Fri Jan 14 01:06:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ricardo Martinez X-Patchwork-Id: 532408 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 0DF3AC4332F for ; Fri, 14 Jan 2022 01:06:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238613AbiANBGz (ORCPT ); Thu, 13 Jan 2022 20:06:55 -0500 Received: from mga04.intel.com ([192.55.52.120]:27438 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238606AbiANBGy (ORCPT ); Thu, 13 Jan 2022 20:06:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642122414; x=1673658414; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=uzozva/1N7/m+s2dpT0GzhJ+v8U7T1UsbKU59h0M1wQ=; b=JUTGHnHoiGaRA7OG5rgnGctI8sASKHB2kESPQ/gFy+/wq/N/jeCwrW6G VeJs+Ux1Qc0Jp4jxKbKzTY3LaEYVmg3cZAVRvOw4dfkd8x3dNGhwWS7qk h/ji/ayh4whb1z0uMSR7qhFXMqHFyS8e7cZ/Z+/a7P9J6OV8DzraxJn/0 udbXyvYjuF4107Fs8SiKMoVOdTYbz2qnkL9pxd9oFlfehk0L75A7imAu+ FQBwMD4xV8SsKAajC0MbVX/txTAYdw2AoM7xIkf6jb2crYzNgs5xwyTFu 8DVR0Cnw5e2SYWiwY8jsfPeeckQp/BnvYI2T4gH11dxF8q0Q4f6Iuio+u w==; X-IronPort-AV: E=McAfee;i="6200,9189,10226"; a="242970846" X-IronPort-AV: E=Sophos;i="5.88,287,1635231600"; d="scan'208";a="242970846" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2022 17:06:53 -0800 X-IronPort-AV: E=Sophos;i="5.88,287,1635231600"; d="scan'208";a="692014184" Received: from rmarti10-desk.jf.intel.com ([134.134.150.146]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2022 17:06:52 -0800 From: Ricardo Martinez To: netdev@vger.kernel.org, linux-wireless@vger.kernel.org Cc: kuba@kernel.org, davem@davemloft.net, johannes@sipsolutions.net, ryazanov.s.a@gmail.com, loic.poulain@linaro.org, m.chetan.kumar@intel.com, chandrashekar.devegowda@intel.com, linuxwwan@intel.com, chiranjeevi.rapolu@linux.intel.com, haijun.liu@mediatek.com, amir.hanania@intel.com, andriy.shevchenko@linux.intel.com, dinesh.sharma@intel.com, eliot.lee@intel.com, ilpo.johannes.jarvinen@intel.com, moises.veleta@intel.com, pierre-louis.bossart@intel.com, muralidharan.sethuraman@intel.com, Soumya.Prakash.Mishra@intel.com, sreehari.kancharla@intel.com, Ricardo Martinez Subject: [PATCH net-next v4 01/13] list: Add list_next_entry_circular() and list_prev_entry_circular() Date: Thu, 13 Jan 2022 18:06:15 -0700 Message-Id: <20220114010627.21104-2-ricardo.martinez@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220114010627.21104-1-ricardo.martinez@linux.intel.com> References: <20220114010627.21104-1-ricardo.martinez@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Add macros to get the next or previous entries and wraparound if needed. For example, calling list_next_entry_circular() on the last element should return the first element in the list. Signed-off-by: Ricardo Martinez --- include/linux/list.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/include/linux/list.h b/include/linux/list.h index dd6c2041d09c..c147eeb2d39d 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -563,6 +563,19 @@ static inline void list_splice_tail_init(struct list_head *list, #define list_next_entry(pos, member) \ list_entry((pos)->member.next, typeof(*(pos)), member) +/** + * list_next_entry_circular - get the next element in list + * @pos: the type * to cursor. + * @head: the list head to take the element from. + * @member: the name of the list_head within the struct. + * + * Wraparound if pos is the last element (return the first element). + * Note, that list is expected to be not empty. + */ +#define list_next_entry_circular(pos, head, member) \ + (list_is_last(&(pos)->member, head) ? \ + list_first_entry(head, typeof(*(pos)), member) : list_next_entry(pos, member)) + /** * list_prev_entry - get the prev element in list * @pos: the type * to cursor @@ -571,6 +584,19 @@ static inline void list_splice_tail_init(struct list_head *list, #define list_prev_entry(pos, member) \ list_entry((pos)->member.prev, typeof(*(pos)), member) +/** + * list_prev_entry_circular - get the prev element in list + * @pos: the type * to cursor. + * @head: the list head to take the element from. + * @member: the name of the list_head within the struct. + * + * Wraparound if pos is the first element (return the last element). + * Note, that list is expected to be not empty. + */ +#define list_prev_entry_circular(pos, head, member) \ + (list_is_first(&(pos)->member, head) ? \ + list_last_entry(head, typeof(*(pos)), member) : list_prev_entry(pos, member)) + /** * list_for_each - iterate over a list * @pos: the &struct list_head to use as a loop cursor.