From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 3DB44328630 for ; Fri, 16 Jan 2026 14:19:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768573154; cv=none; b=fmiVZJaylGP1KDAJBXKb7Z9q9ijhA4hJy7Sx4zFNcuPCbGEapBkPlDui5ZCMGxIL4Yy1/7wwF0BeiZFXXIsQOkW/oFW90bkmy/iErPfULPVHCNSC/i+/1gn711GFjZsgLYZTx1zLoaA5FfjiTNk+efbCpXhS3wAbee1mFDHTDr0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768573154; c=relaxed/simple; bh=Bz5Sd4ylRUWMyWjmOMutYm7RRREWSeDhtOsmPdyzmB8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=TAV1PTSC1QkGtNg+PK44XZ4vuhQqjt5zMNDX7QM+bayY0o2sopSCcOF9qREx6GAIsRpkVV6MwGZiAVGIefsnVsbJr6KqP9LjFQE25trLU7eK5X9PagYRxBk0cyBSw9WjS6fU21gxK6WlX2QVN076hzDwYURFgUIHcdaLNG/Zsjk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=E/Sgm7lW; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="E/Sgm7lW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1768573148; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=jZ1AwD9wd6q4D0KI0M7coJWJc+0XlSyfg1Ez1BoV4lg=; b=E/Sgm7lWTejbwwUHaxxwhlaSIkNjaoH/1+proFQPJt0/t8Lp48T7C5pmR06B7qTT+6rB82 mgnP/81FoWtrZ3j8kTk7nCpgDUHO8SI5m6JJSNcUAGhG15o48tzpzxM9hNvtuImfL79Vxn 4DJv1Ty349ZdkJ/5AhzPw4pkc4q6Mf8= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-604-F2pVo0aANBqVMgu3RQRU1Q-1; Fri, 16 Jan 2026 09:19:07 -0500 X-MC-Unique: F2pVo0aANBqVMgu3RQRU1Q-1 X-Mimecast-MFC-AGG-ID: F2pVo0aANBqVMgu3RQRU1Q_1768573146 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1244318005B3; Fri, 16 Jan 2026 14:19:06 +0000 (UTC) Received: from localhost (unknown [10.72.116.198]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 1168F19560A7; Fri, 16 Jan 2026 14:19:04 +0000 (UTC) From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org Cc: Caleb Sander Mateos , Uday Shankar , Ming Lei Subject: [PATCH V6 00/24] ublk: add UBLK_F_BATCH_IO Date: Fri, 16 Jan 2026 22:18:33 +0800 Message-ID: <20260116141859.719929-1-ming.lei@redhat.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Hello, This patchset adds UBLK_F_BATCH_IO feature for communicating between kernel and ublk server in batching way: - Per-queue vs Per-I/O: Commands operate on queues rather than individual I/Os - Batch processing: Multiple I/Os are handled in single operation - Multishot commands: Use io_uring multishot for reducing submission overhead - Flexible task assignment: Any task can handle any I/O (no per-I/O daemons) - Better load balancing: Tasks can adjust their workload dynamically - help for future optimizations: - blk-mq batch tags free - support io-poll - per-task batch for avoiding per-io lock - fetch command priority - simplify command cancel process with per-queue lock selftest are provided. Performance test result(IOPS) on V3: - page copy tools/testing/selftests/ublk//kublk add -t null -q 16 [-b] - zero copy(--auto_zc) tools/testing/selftests/ublk//kublk add -t null -q 16 --auto_zc [-b] - IO test taskset -c 0-31 fio/t/io_uring -p0 -n $JOBS -r 30 /dev/ublkb0 1) 16 jobs IO - page copy: 37.77M vs. 42.40M(BATCH_IO), +12% - zero copy(--auto_zc): 42.83M vs. 44.43M(BATCH_IO), +3.7% 2) single job IO - page copy: 2.54M vs. 2.6M(BATCH_IO), +2.3% - zero copy(--auto_zc): 3.13M vs. 3.35M(BATCH_IO), +7% Links: https://lore.kernel.org/linux-block/20251202121917.1412280-1-ming.lei@redhat.com/ Links: https://lore.kernel.org/linux-block/20251121015851.3672073-1-ming.lei@redhat.com/ Links: https://lore.kernel.org/linux-block/20251112093808.2134129-1-ming.lei@redhat.com/ Links: https://lore.kernel.org/linux-block/20251023153234.2548062-1-ming.lei@redhat.com/ Links: https://lore.kernel.org/linux-block/20250901100242.3231000-1-ming.lei@redhat.com/ This patchset is based on for-7.0/block with the following two patches: [PATCH v4] ublk: fix ublksrv pid handling for pid namespaces ( https://lore.kernel.org/linux-block/20260115025952.2321238-1-sconnor@purestorage.com/ ) [PATCH 0/3] selftests/ublk: three bug fixes ( https://lore.kernel.org/linux-block/20260113085805.233214-1-ming.lei@redhat.com/ ) V6: - rebase on for-7.0/block - fix ublk_handle_non_batch_cmd() (Caleb Sander Mateos) - add `ublk: refactor ublk_queue_rq() and add ublk_batch_queue_rq()` (Caleb Sander Mateos) - add `ublk: fix batch I/O recovery -ENODEV error` - increase selftest timeout for running more things in some generic tests - fix kublk utility wrt. ->cmd_inflight accounting for BATCH_IO - pass all selftest after applying the io_uring cancel fix V5: - rebase on for-6.19/block - fix fetch command leak in ublk_batch_attach() by marking correct uring_cmd as cancellable - add ublk_batch_queue_rqs() for building per-queue batch - add __ublk_deinit_queue() for fixing failure path of initializing queue(Caleb Sander Mateos) - explicitly disable UBLK_F_NEED_GET_DATA for BATCH_IO(Caleb Sander Mateos) - kill unnecessary check in ublk_batch_commit_io_check()(Caleb Sander Mateos) - rename `ublk_batch_fcmd` as `ublk_batch_fetch_cmd`(Caleb Sander Mateos) - improve ublk_batch_dispatch() by not running inline dispatch for different fetch command(Caleb Sander Mateos) - use READ_ONCE() for reading all ubq->active_fcmd(Caleb Sander Mateos) - simplify ublk_abort_batch_queue()(Caleb Sander Mateos) - improve handling for non-batch commands(Caleb Sander Mateos) - document fetch command lifetime(Caleb Sander Mateos) - patch style, sizeof(tag), signed/unsigned changes(Caleb Sander Mateos) - add recovery function test for BATCH_IO in generic_04/genereic_05 V4: - fix handling in case of running out of mshot buffer, request has to be un-prepared for zero copy - don't expose unused tag to userspace - replace fixed buffer with plain user buffer for UBLK_U_IO_PREP_IO_CMDS and UBLK_U_IO_COMMIT_IO_CMDS - replace iov iterator with plain copy_from_user() for ublk_walk_cmd_buf(), code is simplified with performance improvement - don't touch sqe->len for UBLK_U_IO_PREP_IO_CMDS and UBLK_U_IO_COMMIT_IO_CMDS(Caleb Sander Mateos) - use READ_ONCE() for access sqe->addr (Caleb Sander Mateos) - all kinds of patch style fix(Caleb Sander Mateos) - inline __kfifo_alloc() (Caleb Sander Mateos) V3: - rebase on for-6.19/block - use blk_mq_end_request_batch() to free requests in batch, only for page copy - fix one IO hang issue because of memory barrier order, comments on the memory barrier pairing - add NUMA ware kfifo_alloc_node() - fix one build warning reported by 0-DAY CI - selftests improvement & fix V2: - ublk_config_io_buf() vs. __ublk_fetch() order - code style clean - use READ_ONCE() to cache sqe data because sqe copy becomes conditional recently - don't use sqe->len for UBLK_U_IO_PREP_IO_CMDS & UBLK_U_IO_COMMIT_IO_CMDS - fix one build warning - fix build_user_data() - run performance analysis, and find one bug in io_uring_cmd_buffer_select(), fix is posted already Ming Lei (24): ublk: define ublk_ch_batch_io_fops for the coming feature F_BATCH_IO ublk: prepare for not tracking task context for command batch ublk: add new batch command UBLK_U_IO_PREP_IO_CMDS & UBLK_U_IO_COMMIT_IO_CMDS ublk: handle UBLK_U_IO_PREP_IO_CMDS ublk: handle UBLK_U_IO_COMMIT_IO_CMDS ublk: add io events fifo structure ublk: add batch I/O dispatch infrastructure ublk: add UBLK_U_IO_FETCH_IO_CMDS for batch I/O processing ublk: refactor ublk_queue_rq() and add ublk_batch_queue_rq() ublk: abort requests filled in event kfifo ublk: add new feature UBLK_F_BATCH_IO ublk: document feature UBLK_F_BATCH_IO ublk: implement batch request completion via blk_mq_end_request_batch() ublk: fix batch I/O recovery -ENODEV error selftests: ublk: fix user_data truncation for tgt_data >= 256 selftests: ublk: replace assert() with ublk_assert() selftests: ublk: add ublk_io_buf_idx() for returning io buffer index selftests: ublk: add batch buffer management infrastructure selftests: ublk: handle UBLK_U_IO_PREP_IO_CMDS selftests: ublk: handle UBLK_U_IO_COMMIT_IO_CMDS selftests: ublk: handle UBLK_U_IO_FETCH_IO_CMDS selftests: ublk: increase timeout to 150 seconds selftests: ublk: add --batch/-b for enabling F_BATCH_IO selftests: ublk: support arbitrary threads/queues combination Documentation/block/ublk.rst | 64 +- drivers/block/ublk_drv.c | 1303 ++++++++++++++++- include/uapi/linux/ublk_cmd.h | 84 ++ tools/testing/selftests/ublk/Makefile | 8 + tools/testing/selftests/ublk/batch.c | 607 ++++++++ tools/testing/selftests/ublk/common.c | 2 +- tools/testing/selftests/ublk/file_backed.c | 11 +- tools/testing/selftests/ublk/kublk.c | 149 +- tools/testing/selftests/ublk/kublk.h | 195 ++- tools/testing/selftests/ublk/null.c | 18 +- tools/testing/selftests/ublk/settings | 1 + tools/testing/selftests/ublk/stripe.c | 17 +- tools/testing/selftests/ublk/test_batch_01.sh | 32 + tools/testing/selftests/ublk/test_batch_02.sh | 30 + tools/testing/selftests/ublk/test_batch_03.sh | 30 + .../testing/selftests/ublk/test_generic_04.sh | 5 + .../testing/selftests/ublk/test_generic_05.sh | 5 + .../testing/selftests/ublk/test_stress_08.sh | 45 + .../testing/selftests/ublk/test_stress_09.sh | 44 + tools/testing/selftests/ublk/utils.h | 64 + 20 files changed, 2569 insertions(+), 145 deletions(-) create mode 100644 tools/testing/selftests/ublk/batch.c create mode 100644 tools/testing/selftests/ublk/settings create mode 100755 tools/testing/selftests/ublk/test_batch_01.sh create mode 100755 tools/testing/selftests/ublk/test_batch_02.sh create mode 100755 tools/testing/selftests/ublk/test_batch_03.sh create mode 100755 tools/testing/selftests/ublk/test_stress_08.sh create mode 100755 tools/testing/selftests/ublk/test_stress_09.sh -- 2.47.0