From nobody Tue Feb 10 01:35:33 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=git.sr.ht Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 169024932365228.79633018220113; Mon, 24 Jul 2023 18:42:03 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qO72W-00084Y-CO; Mon, 24 Jul 2023 21:40:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qO72T-00083L-HK for qemu-devel@nongnu.org; Mon, 24 Jul 2023 21:40:37 -0400 Received: from mail-b.sr.ht ([173.195.146.151]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qO72R-0008LE-RK for qemu-devel@nongnu.org; Mon, 24 Jul 2023 21:40:37 -0400 Received: from git.sr.ht (unknown [173.195.146.142]) by mail-b.sr.ht (Postfix) with ESMTPSA id 9138C11EF58; Tue, 25 Jul 2023 01:40:32 +0000 (UTC) Authentication-Results: mail-b.sr.ht; dkim=none From: ~hyman Date: Thu, 08 Jun 2023 00:12:40 +0800 Subject: [PATCH QEMU v10 7/9] migration: Implement dirty-limit convergence algorithm MIME-Version: 1.0 Message-ID: <169024923116.19090.10825599068950039132-7@git.sr.ht> X-Mailer: git.sr.ht In-Reply-To: <169024923116.19090.10825599068950039132-0@git.sr.ht> To: qemu-devel@nongnu.org Cc: Juan Quintela , Peter Xu , Leonardo Bras , Eric Blake , Markus Armbruster , Thomas Huth , Laurent Vivier , Paolo Bonzini Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=173.195.146.151; envelope-from=outgoing@sr.ht; helo=mail-b.sr.ht X-Spam_score_int: 15 X-Spam_score: 1.5 X-Spam_bar: + X-Spam_report: (1.5 / 5.0 requ) BAYES_00=-1.9, DATE_IN_PAST_96_XX=3.405, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: ~hyman Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1690249325376100003 From: Hyman Huang(=E9=BB=84=E5=8B=87) Implement dirty-limit convergence algorithm for live migration, which is kind of like auto-converge algo but using dirty-limit instead of cpu throttle to make migration convergent. Enable dirty page limit if dirty_rate_high_cnt greater than 2 when dirty-limit capability enabled, Disable dirty-limit if migration be canceled. Note that "set_vcpu_dirty_limit", "cancel_vcpu_dirty_limit" commands are not allowed during dirty-limit live migration. Signed-off-by: Hyman Huang(=E9=BB=84=E5=8B=87) Reviewed-by: Markus Armbruster Reviewed-by: Juan Quintela --- migration/migration.c | 3 +++ migration/ram.c | 36 ++++++++++++++++++++++++++++++++++++ migration/trace-events | 1 + softmmu/dirtylimit.c | 29 +++++++++++++++++++++++++++++ 4 files changed, 69 insertions(+) diff --git a/migration/migration.c b/migration/migration.c index 91bba630a8..619af62461 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -166,6 +166,9 @@ void migration_cancel(const Error *error) if (error) { migrate_set_error(current_migration, error); } + if (migrate_dirty_limit()) { + qmp_cancel_vcpu_dirty_limit(false, -1, NULL); + } migrate_fd_cancel(current_migration); } =20 diff --git a/migration/ram.c b/migration/ram.c index 1d9300f4c5..9040d66e61 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -46,6 +46,7 @@ #include "qapi/error.h" #include "qapi/qapi-types-migration.h" #include "qapi/qapi-events-migration.h" +#include "qapi/qapi-commands-migration.h" #include "qapi/qmp/qerror.h" #include "trace.h" #include "exec/ram_addr.h" @@ -59,6 +60,8 @@ #include "multifd.h" #include "sysemu/runstate.h" #include "options.h" +#include "sysemu/dirtylimit.h" +#include "sysemu/kvm.h" =20 #include "hw/boards.h" /* for machine_dump_guest_core() */ =20 @@ -984,6 +987,37 @@ static void migration_update_rates(RAMState *rs, int64= _t end_time) } } =20 +/* + * Enable dirty-limit to throttle down the guest + */ +static void migration_dirty_limit_guest(void) +{ + /* + * dirty page rate quota for all vCPUs fetched from + * migration parameter 'vcpu_dirty_limit' + */ + static int64_t quota_dirtyrate; + MigrationState *s =3D migrate_get_current(); + + /* + * If dirty limit already enabled and migration parameter + * vcpu-dirty-limit untouched. + */ + if (dirtylimit_in_service() && + quota_dirtyrate =3D=3D s->parameters.vcpu_dirty_limit) { + return; + } + + quota_dirtyrate =3D s->parameters.vcpu_dirty_limit; + + /* + * Set all vCPU a quota dirtyrate, note that the second + * parameter will be ignored if setting all vCPU for the vm + */ + qmp_set_vcpu_dirty_limit(false, -1, quota_dirtyrate, NULL); + trace_migration_dirty_limit_guest(quota_dirtyrate); +} + static void migration_trigger_throttle(RAMState *rs) { uint64_t threshold =3D migrate_throttle_trigger_threshold(); @@ -1013,6 +1047,8 @@ static void migration_trigger_throttle(RAMState *rs) trace_migration_throttle(); mig_throttle_guest_down(bytes_dirty_period, bytes_dirty_threshold); + } else if (migrate_dirty_limit()) { + migration_dirty_limit_guest(); } } } diff --git a/migration/trace-events b/migration/trace-events index 5259c1044b..580895e86e 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -93,6 +93,7 @@ migration_bitmap_sync_start(void) "" migration_bitmap_sync_end(uint64_t dirty_pages) "dirty_pages %" PRIu64 migration_bitmap_clear_dirty(char *str, uint64_t start, uint64_t size, uns= igned long page) "rb %s start 0x%"PRIx64" size 0x%"PRIx64" page 0x%lx" migration_throttle(void) "" +migration_dirty_limit_guest(int64_t dirtyrate) "guest dirty page rate limi= t %" PRIi64 " MB/s" ram_discard_range(const char *rbname, uint64_t start, size_t len) "%s: sta= rt: %" PRIx64 " %zx" ram_load_loop(const char *rbname, uint64_t addr, int flags, void *host) "%= s: addr: 0x%" PRIx64 " flags: 0x%x host: %p" ram_load_postcopy_loop(int channel, uint64_t addr, int flags) "chan=3D%d a= ddr=3D0x%" PRIx64 " flags=3D0x%x" diff --git a/softmmu/dirtylimit.c b/softmmu/dirtylimit.c index 953ef934bc..5134296667 100644 --- a/softmmu/dirtylimit.c +++ b/softmmu/dirtylimit.c @@ -436,6 +436,23 @@ static void dirtylimit_cleanup(void) dirtylimit_state_finalize(); } =20 +/* + * dirty page rate limit is not allowed to set if migration + * is running with dirty-limit capability enabled. + */ +static bool dirtylimit_is_allowed(void) +{ + MigrationState *ms =3D migrate_get_current(); + + if (migration_is_running(ms->state) && + (!qemu_thread_is_self(&ms->thread)) && + migrate_dirty_limit() && + dirtylimit_in_service()) { + return false; + } + return true; +} + void qmp_cancel_vcpu_dirty_limit(bool has_cpu_index, int64_t cpu_index, Error **errp) @@ -449,6 +466,12 @@ void qmp_cancel_vcpu_dirty_limit(bool has_cpu_index, return; } =20 + if (!dirtylimit_is_allowed()) { + error_setg(errp, "can't cancel dirty page rate limit while" + " migration is running"); + return; + } + if (!dirtylimit_in_service()) { return; } @@ -499,6 +522,12 @@ void qmp_set_vcpu_dirty_limit(bool has_cpu_index, return; } =20 + if (!dirtylimit_is_allowed()) { + error_setg(errp, "can't set dirty page rate limit while" + " migration is running"); + return; + } + if (!dirty_rate) { qmp_cancel_vcpu_dirty_limit(has_cpu_index, cpu_index, errp); return; --=20 2.38.5