From patchwork Mon Mar 25 04:44:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 782986 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 15CE01C32A9; Mon, 25 Mar 2024 04:45:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711341938; cv=none; b=peGhShU9adXrWco9E/TIVzwfgE9MhhomjXWmo1A8FjeaEnoSMbh9ZJoUZFJ+GHKqCKE3YGUYsaqhJ3qycWWNcrX0mK1T1aLeu12zVyDuFs9SdLwTWlPbn4fjAlpqGM0Mta/Ogw4aAsbsLG0x8NkcDfroA2ctOISb6TgHks63nL8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711341938; c=relaxed/simple; bh=q+XsDtYo/2/RZEgIqOxru5p8iCOQ4U+aEKwxrk47H/g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VGKhZsA24JDOATBvpRlWYABjn3MyOp8wBxN7kKf1MzoF+9NMhzPG2ul0ZgXZuqRzu8LNx7OltVPQ2SECMuvunakG7VGqASX9XJRoyypKM3inWyz/Jp0yDamyD//e3A7cRhsGPrv1gRHPNQkzr3RVTEeTVuzeLlzn0nNF0B0sMt4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pC/Z63cb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pC/Z63cb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ECFCAC433F1; Mon, 25 Mar 2024 04:45:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711341938; bh=q+XsDtYo/2/RZEgIqOxru5p8iCOQ4U+aEKwxrk47H/g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pC/Z63cb28uKhuEElYL6VeH7nZSMJTnsMuU/0lFUERJY56FPo4lTXqdGH8N0ROiRf Vk49s4Xdr6lWwTmacFP8ws6HbSWLACSj1D2g4a/uPUnb825nRFguRwnXEW5sJHC6Vh FL+6hzooKOtX96DM1VcHobl/ZuTut5YqIhTdsukrV1/lFlkZPE0CkY05bE6p490Ine HPYIrw84NlrR2Ww1okwEF4L3HoKObKY0e3UEqhghz4FX5zPyNa9xFJd6dD9U+42S+P wYccxdttChc/tPzgrJp8CvBbGy5ObkhRpEHZupbdnfzBnZxWud9eut3MM/B0/s9j26 7JvzHO0et7k5A== From: Damien Le Moal To: linux-block@vger.kernel.org, Jens Axboe , linux-scsi@vger.kernel.org, "Martin K . Petersen" , dm-devel@lists.linux.dev, Mike Snitzer Cc: Christoph Hellwig Subject: [PATCH v2 23/28] block: Remove elevator required features Date: Mon, 25 Mar 2024 13:44:47 +0900 Message-ID: <20240325044452.3125418-24-dlemoal@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240325044452.3125418-1-dlemoal@kernel.org> References: <20240325044452.3125418-1-dlemoal@kernel.org> Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The only elevator feature ever implemented is ELEVATOR_F_ZBD_SEQ_WRITE for signaling that a scheduler implements zone write locking to tightly control the dispatching order of write operations to zoned block devices. With the removal of zone write locking support in mq-deadline and the reliance of all block device drivers on the block layer zone write plugging to control ordering of write operations to zones, the elevator feature ELEVATOR_F_ZBD_SEQ_WRITE is completely unused. Remove it, and also remove the now unused code for filtering the possible schedulers for a block device based on required features. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig --- block/blk-settings.c | 16 --------------- block/elevator.c | 46 +++++------------------------------------- block/elevator.h | 1 - include/linux/blkdev.h | 10 --------- 4 files changed, 5 insertions(+), 68 deletions(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index 82c61d2e4bb8..31d882ac72d4 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -1053,22 +1053,6 @@ void blk_queue_write_cache(struct request_queue *q, bool wc, bool fua) } EXPORT_SYMBOL_GPL(blk_queue_write_cache); -/** - * blk_queue_required_elevator_features - Set a queue required elevator features - * @q: the request queue for the target device - * @features: Required elevator features OR'ed together - * - * Tell the block layer that for the device controlled through @q, only the - * only elevators that can be used are those that implement at least the set of - * features specified by @features. - */ -void blk_queue_required_elevator_features(struct request_queue *q, - unsigned int features) -{ - q->required_elevator_features = features; -} -EXPORT_SYMBOL_GPL(blk_queue_required_elevator_features); - /** * blk_queue_can_use_dma_map_merging - configure queue for merging segments. * @q: the request queue for the device diff --git a/block/elevator.c b/block/elevator.c index 5ff093cb3cf8..f64ebd726e58 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -83,13 +83,6 @@ bool elv_bio_merge_ok(struct request *rq, struct bio *bio) } EXPORT_SYMBOL(elv_bio_merge_ok); -static inline bool elv_support_features(struct request_queue *q, - const struct elevator_type *e) -{ - return (q->required_elevator_features & e->elevator_features) == - q->required_elevator_features; -} - /** * elevator_match - Check whether @e's name or alias matches @name * @e: Scheduler to test @@ -120,7 +113,7 @@ static struct elevator_type *elevator_find_get(struct request_queue *q, spin_lock(&elv_list_lock); e = __elevator_find(name); - if (e && (!elv_support_features(q, e) || !elevator_tryget(e))) + if (e && (!elevator_tryget(e))) e = NULL; spin_unlock(&elv_list_lock); return e; @@ -580,34 +573,8 @@ static struct elevator_type *elevator_get_default(struct request_queue *q) } /* - * Get the first elevator providing the features required by the request queue. - * Default to "none" if no matching elevator is found. - */ -static struct elevator_type *elevator_get_by_features(struct request_queue *q) -{ - struct elevator_type *e, *found = NULL; - - spin_lock(&elv_list_lock); - - list_for_each_entry(e, &elv_list, list) { - if (elv_support_features(q, e)) { - found = e; - break; - } - } - - if (found && !elevator_tryget(found)) - found = NULL; - - spin_unlock(&elv_list_lock); - return found; -} - -/* - * For a device queue that has no required features, use the default elevator - * settings. Otherwise, use the first elevator available matching the required - * features. If no suitable elevator is find or if the chosen elevator - * initialization fails, fall back to the "none" elevator (no elevator). + * Use the default elevator settings. If the chosen elevator initialization + * fails, fall back to the "none" elevator (no elevator). */ void elevator_init_mq(struct request_queue *q) { @@ -622,10 +589,7 @@ void elevator_init_mq(struct request_queue *q) if (unlikely(q->elevator)) return; - if (!q->required_elevator_features) - e = elevator_get_default(q); - else - e = elevator_get_by_features(q); + e = elevator_get_default(q); if (!e) return; @@ -781,7 +745,7 @@ ssize_t elv_iosched_show(struct request_queue *q, char *name) list_for_each_entry(e, &elv_list, list) { if (e == cur) len += sprintf(name+len, "[%s] ", e->elevator_name); - else if (elv_support_features(q, e)) + else len += sprintf(name+len, "%s ", e->elevator_name); } spin_unlock(&elv_list_lock); diff --git a/block/elevator.h b/block/elevator.h index 7ca3d7b6ed82..e9a050a96e53 100644 --- a/block/elevator.h +++ b/block/elevator.h @@ -74,7 +74,6 @@ struct elevator_type struct elv_fs_entry *elevator_attrs; const char *elevator_name; const char *elevator_alias; - const unsigned int elevator_features; struct module *elevator_owner; #ifdef CONFIG_BLK_DEBUG_FS const struct blk_mq_debugfs_attr *queue_debugfs_attrs; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 2e0087b4c37d..82cda82e9891 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -456,8 +456,6 @@ struct request_queue { atomic_t nr_active_requests_shared_tags; - unsigned int required_elevator_features; - struct blk_mq_tags *sched_shared_tags; struct list_head icq_list; @@ -962,14 +960,6 @@ disk_alloc_independent_access_ranges(struct gendisk *disk, int nr_ia_ranges); void disk_set_independent_access_ranges(struct gendisk *disk, struct blk_independent_access_ranges *iars); -/* - * Elevator features for blk_queue_required_elevator_features: - */ -/* Supports zoned block devices sequential write constraint */ -#define ELEVATOR_F_ZBD_SEQ_WRITE (1U << 0) - -extern void blk_queue_required_elevator_features(struct request_queue *q, - unsigned int features); extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q, struct device *dev);