{"id":2220014,"url":"http://patchwork.ozlabs.org/api/1.2/patches/2220014/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260405200735.3075407-2-jhkim@linux.ibm.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.2/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":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260405200735.3075407-2-jhkim@linux.ibm.com>","list_archive_url":null,"date":"2026-04-05T20:07:32","name":"[v3,1/3] aio-poll: avoid unnecessary polling time computation","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"e1a43bd44d6e67dce16bf780ce33eb2333a9330d","submitter":{"id":91012,"url":"http://patchwork.ozlabs.org/api/1.2/people/91012/?format=json","name":"Jaehoon Kim","email":"jhkim@linux.ibm.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260405200735.3075407-2-jhkim@linux.ibm.com/mbox/","series":[{"id":498805,"url":"http://patchwork.ozlabs.org/api/1.2/series/498805/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=498805","date":"2026-04-05T20:07:32","name":"improve aio-polling efficiency","version":3,"mbox":"http://patchwork.ozlabs.org/series/498805/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2220014/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2220014/checks/","tags":{},"related":[],"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=ibm.com header.i=@ibm.com header.a=rsa-sha256\n header.s=pp1 header.b=EcEkgQjy;\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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a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc\n :content-transfer-encoding:date:from:in-reply-to:message-id\n :mime-version:references:subject:to; s=pp1; bh=NEywkYVaDUsxcrPTH\n Fev8EFSNbDutRhyN0hAgTeSJSc=; b=EcEkgQjyNvg6vTyHjJcZlrZ7mKdN8UBIP\n t6zbLjMOConN5agOjehQZpfziNoaL3ypq4iOlBWAQELgYI3mOVw/SAw8BfkY13FC\n Q2vOBst9KTK3gkZEQo+vVUPsv3fchjtfuZ6PLfYiRdcGP4x7TwyYkiSNyCbVk0wI\n g1jB8l4QTjIlkzwQa5csytZIkhidmh5Xagy4MjBz3jnVQdUgaPh8zCupgghzKGhg\n kgpQfL/BwnDwwHEvlWXnJv3o3oi3wGUkOcuigp3Cilsw8FKwLG1I832Idr9TaIdW\n IaI+S9phHg5EB66Mg/+Dhv+KVRc0AFh1bxcHTLy2bpRpVdtVQaYIg==","From":"Jaehoon Kim ","To":"qemu-devel@nongnu.org, qemu-block@nongnu.org","Cc":"pbonzini@redhat.com, stefanha@redhat.com, fam@euphon.net,\n armbru@redhat.com, eblake@redhat.com, berrange@redhat.com,\n eduardo@habkost.net, dave@treblig.org, sw@weilnetz.de,\n mjrosato@linux.ibm.com, farman@linux.ibm.com,\n Jaehoon Kim ","Subject":"[PATCH v3 1/3] aio-poll: avoid unnecessary polling time computation","Date":"Sun, 5 Apr 2026 15:07:32 -0500","Message-ID":"<20260405200735.3075407-2-jhkim@linux.ibm.com>","X-Mailer":"git-send-email 2.43.0","In-Reply-To":"<20260405200735.3075407-1-jhkim@linux.ibm.com>","References":"<20260405200735.3075407-1-jhkim@linux.ibm.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-TM-AS-GCONF":"00","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDA1MDIwNiBTYWx0ZWRfXzJM4GxVp3AhJ\n +Lx6hBWjRWY4w3xjrtVj6oXOIWrzXPrTVVtM4mggYNkb452bvE6NEZDwucYjXmExqlpnWRCXo+U\n dDH9qCWXKbHBSprmifKAb7JvSTzM+nurqKM6tMxh+uHpO4zv6rGRQsFMdWGBZiiyXgMw/3zHS+k\n tesBm5/YuHQW6NYSSe1uXpVHNyLI0fK6R7/KGDKJiVNWEQg+8BjUW/46eDqNc+7fZmPESnCWrDN\n PJBHL5e8s3/+E1wf4k4qwLIKCO0m7e/J7nLMcnEV38fq4mdehM/ePMK1T9m/uHe8ar9k0RWhegN\n SdZHe1j1UqPy/wQrhZHZj8Xa+szxQUwEpQM0faHbbrIJDAskJjVv1p2Uhd86fYvGehs7g+Jcvvz\n WbnLus5u49EdiL508G9SwoxibXvFB0ZsTObYbcmT40RE97qRayZb2jl2x9+nc1AhWVROsTKY9fj\n CiitMPXZM2CsNL/xGGw==","X-Proofpoint-GUID":"cpMl8QlInP2aQPbccIFolPUZe-Dp6EnV","X-Proofpoint-ORIG-GUID":"cpMl8QlInP2aQPbccIFolPUZe-Dp6EnV","X-Authority-Analysis":"v=2.4 cv=HJvO14tv c=1 sm=1 tr=0 ts=69d2c10e cx=c_pps\n a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17\n a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22\n a=U7nrCbtTmkRpXpFmAIza:22 a=VnNF1IyMAAAA:8 a=20KFwNOVAAAA:8\n a=6MqEkq6nHlEWUoCmaegA:9","X-Proofpoint-Virus-Version":"vendor=baseguard\n engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49\n definitions=2026-04-05_06,2026-04-03_01,2025-10-01_01","X-Proofpoint-Spam-Details":"rule=outbound_notspam policy=outbound score=0\n impostorscore=0 suspectscore=0 clxscore=1015 lowpriorityscore=0 adultscore=0\n malwarescore=0 spamscore=0 phishscore=0 priorityscore=1501 bulkscore=0\n classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0\n reason=mlx scancount=1 engine=8.22.0-2603050001 definitions=main-2604050206","Received-SPF":"pass client-ip=148.163.156.1; envelope-from=jhkim@linux.ibm.com;\n helo=mx0a-001b2d01.pphosted.com","X-Spam_score_int":"-26","X-Spam_score":"-2.7","X-Spam_bar":"--","X-Spam_report":"(-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7,\n RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001,\n RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001,\n SPF_HELO_NONE=0.001, 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":"Nodes are no longer added to poll_aio_handlers when adaptive polling is\ndisabled, preventing unnecessary try_poll_mode() calls. This avoids\niterating over all nodes to compute max_ns unnecessarily when polling\nis disabled.\n\nSigned-off-by: Jaehoon Kim \nReviewed-by: Stefan Hajnoczi \n---\n util/aio-posix.c | 11 ++++++-----\n 1 file changed, 6 insertions(+), 5 deletions(-)","diff":"diff --git a/util/aio-posix.c b/util/aio-posix.c\nindex 488d964611..351847c6fb 100644\n--- a/util/aio-posix.c\n+++ b/util/aio-posix.c\n@@ -307,9 +307,8 @@ static bool aio_dispatch_handler(AioContext *ctx, AioHandler *node)\n * fdmon_supports_polling(), but only until the fd fires for the first\n * time.\n */\n- if (!QLIST_IS_INSERTED(node, node_deleted) &&\n- !QLIST_IS_INSERTED(node, node_poll) &&\n- node->io_poll) {\n+ if (ctx->poll_max_ns && !QLIST_IS_INSERTED(node, node_deleted) &&\n+ !QLIST_IS_INSERTED(node, node_poll) && node->io_poll) {\n trace_poll_add(ctx, node, node->pfd.fd, revents);\n if (ctx->poll_started && node->io_poll_begin) {\n node->io_poll_begin(node->opaque);\n@@ -631,7 +630,7 @@ static void adjust_polling_time(AioContext *ctx, AioPolledEvent *poll,\n bool aio_poll(AioContext *ctx, bool blocking)\n {\n AioHandlerList ready_list = QLIST_HEAD_INITIALIZER(ready_list);\n- bool progress;\n+ bool progress = false;\n bool use_notify_me;\n int64_t timeout;\n int64_t start = 0;\n@@ -656,7 +655,9 @@ bool aio_poll(AioContext *ctx, bool blocking)\n }\n \n timeout = blocking ? aio_compute_timeout(ctx) : 0;\n- progress = try_poll_mode(ctx, &ready_list, &timeout);\n+ if (ctx->poll_max_ns != 0) {\n+ progress = try_poll_mode(ctx, &ready_list, &timeout);\n+ }\n assert(!(timeout && progress));\n \n /*\n","prefixes":["v3","1/3"]}