{"id":2222003,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2222003/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260410150457.85190-5-zhangckid@gmail.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260410150457.85190-5-zhangckid@gmail.com>","date":"2026-04-10T15:04:47","name":"[V6,04/14] blockdev: Update tracking iothread users with holder name","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"31efd602e1783a2168d30b8be7c3e8bee4002e05","submitter":{"id":72278,"url":"http://patchwork.ozlabs.org/api/1.1/people/72278/?format=json","name":"Zhang Chen","email":"zhangckid@gmail.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260410150457.85190-5-zhangckid@gmail.com/mbox/","series":[{"id":499477,"url":"http://patchwork.ozlabs.org/api/1.1/series/499477/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=499477","date":"2026-04-10T15:04:43","name":"iothread: Support tracking and querying IOThread holders","version":6,"mbox":"http://patchwork.ozlabs.org/series/499477/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2222003/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2222003/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=VD2kRAQi;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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David Alan Gilbert\" ,\n Eric Blake , Markus Armbruster ,\n \"Michael S . Tsirkin\" ,\n Stefan Hajnoczi ","Cc":"Zhang Chen ","Subject":"[PATCH V6 04/14] blockdev: Update tracking iothread users with holder\n name","Date":"Fri, 10 Apr 2026 23:04:47 +0800","Message-ID":"<20260410150457.85190-5-zhangckid@gmail.com>","X-Mailer":"git-send-email 2.49.0","In-Reply-To":"<20260410150457.85190-1-zhangckid@gmail.com>","References":"<20260410150457.85190-1-zhangckid@gmail.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Received-SPF":"pass client-ip=2607:f8b0:4864:20::102f;\n envelope-from=zhangckid@gmail.com; helo=mail-pj1-x102f.google.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001,\n RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001,\n SPF_PASS=-0.001 autolearn=ham autolearn_force=no","X-Spam_action":"no action","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"Currently, x-blockdev-set-iothread changes the AioContext but does not\ntrack the IOThread object itself within the block layer. This makes it\ndifficult to manage IOThread reference counting (put/get) during\ndynamic context switching.\n\nIntroduce an 'iothread' field to BlockDriverState to store the current\nassigned IOThread. Update qmp_x_blockdev_set_iothread to perform\nproper reference counting using iothread_ref/put when moving nodes\nbetween an IOThread and the main loop.\n\nThis ensures 'info iothreads' (holders) accurately reflects the block\ndevice attachment state after dynamic migrations.\n\nSigned-off-by: Zhang Chen \n---\n blockdev.c | 6 +++++-\n include/block/block_int-common.h | 5 +++++\n 2 files changed, 10 insertions(+), 1 deletion(-)","diff":"diff --git a/blockdev.c b/blockdev.c\nindex 6e86c6262f..6e20579187 100644\n--- a/blockdev.c\n+++ b/blockdev.c\n@@ -3683,8 +3683,12 @@ void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,\n goto out;\n }\n \n- new_context = iothread_get_aio_context(obj);\n+ new_context = iothread_ref_and_get_aio_context(obj, node_name);\n+ bs->iothread = obj;\n } else {\n+ if (bs->iothread) {\n+ iothread_put_aio_context(bs->iothread, node_name);\n+ }\n new_context = qemu_get_aio_context();\n }\n \ndiff --git a/include/block/block_int-common.h b/include/block/block_int-common.h\nindex 147c08155f..6edaf53377 100644\n--- a/include/block/block_int-common.h\n+++ b/include/block/block_int-common.h\n@@ -1101,6 +1101,8 @@ typedef struct BdrvBlockStatusCache {\n int64_t data_end;\n } BdrvBlockStatusCache;\n \n+typedef struct IOThread IOThread;\n+\n struct BlockDriverState {\n /*\n * Protected by big QEMU lock or read-only after opening. No special\n@@ -1289,6 +1291,9 @@ struct BlockDriverState {\n \n /* array of write pointers' location of each zone in the zoned device. */\n BlockZoneWps *wps;\n+\n+ /* Track the iothread for detach aio context*/\n+ IOThread *iothread;\n };\n \n struct BlockBackendRootState {\n","prefixes":["V6","04/14"]}