From nobody Sun Feb 8 21:47:37 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1519981770973778.3541309903375; Fri, 2 Mar 2018 01:09:30 -0800 (PST) Received: from localhost ([::1]:33548 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ergh0-00008U-77 for importer@patchew.org; Fri, 02 Mar 2018 04:09:30 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46199) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1erge6-0006WC-SI for qemu-devel@nongnu.org; Fri, 02 Mar 2018 04:06:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1erge4-0000Fi-IB for qemu-devel@nongnu.org; Fri, 02 Mar 2018 04:06:30 -0500 Received: from mga05.intel.com ([192.55.52.43]:56819) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1erge4-0000EQ-9H for qemu-devel@nongnu.org; Fri, 02 Mar 2018 04:06:28 -0500 Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Mar 2018 01:06:27 -0800 Received: from devel-ww.sh.intel.com ([10.239.48.110]) by fmsmga006.fm.intel.com with ESMTP; 02 Mar 2018 01:06:25 -0800 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,411,1515484800"; d="scan'208";a="208316638" From: Wei Wang To: qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, mst@redhat.com, quintela@redhat.com, dgilbert@redhat.com Date: Fri, 2 Mar 2018 16:47:30 +0800 Message-Id: <1519980450-3404-4-git-send-email-wei.w.wang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1519980450-3404-1-git-send-email-wei.w.wang@intel.com> References: <1519980450-3404-1-git-send-email-wei.w.wang@intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.43 Subject: [Qemu-devel] [PATCH v3 3/3] migration: use the free page hint feature from balloon X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: yang.zhang.wz@gmail.com, quan.xu0@gmail.com, liliang.opensource@gmail.com, wei.w.wang@intel.com, pbonzini@redhat.com, nilal@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Start the free page optimization when the bulk stage starts. In case the guest is slow in reporting, actively stops it when the bulk stage ends. The optimization avoids sending guest free pages during the bulk stage. Currently, the optimization is added to precopy only. Signed-off-by: Wei Wang CC: Dr. David Alan Gilbert CC: Juan Quintela CC: Michael S. Tsirkin --- migration/ram.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index 769a0f6..f6af7e6 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -51,6 +51,7 @@ #include "qemu/rcu_queue.h" #include "migration/colo.h" #include "migration/block.h" +#include "sysemu/balloon.h" =20 /***********************************************************/ /* ram save/restore */ @@ -208,6 +209,8 @@ struct RAMState { uint32_t last_version; /* We are in the first round */ bool ram_bulk_stage; + /* The free pages optimization feature is supported */ + bool free_page_support; /* How many times we have dirty too many pages */ int dirty_rate_high_cnt; /* these variables are used for bitmap sync */ @@ -775,7 +778,7 @@ unsigned long migration_bitmap_find_dirty(RAMState *rs,= RAMBlock *rb, unsigned long *bitmap =3D rb->bmap; unsigned long next; =20 - if (rs->ram_bulk_stage && start > 0) { + if (rs->ram_bulk_stage && start > 0 && !rs->free_page_support) { next =3D start + 1; } else { next =3D find_next_bit(bitmap, size, start); @@ -1225,6 +1228,10 @@ static bool find_dirty_block(RAMState *rs, PageSearc= hStatus *pss, bool *again) /* Flag that we've looped */ pss->complete_round =3D true; rs->ram_bulk_stage =3D false; + if (rs->free_page_support) { + balloon_free_page_stop(); + rs->free_page_support =3D false; + } if (migrate_use_xbzrle()) { /* If xbzrle is on, stop using the data compression at this * point. In theory, xbzrle can do better than compression. @@ -1656,6 +1663,8 @@ static void ram_state_reset(RAMState *rs) rs->last_page =3D 0; rs->last_version =3D ram_list.version; rs->ram_bulk_stage =3D true; + rs->free_page_support =3D balloon_free_page_support() & + !migration_in_postcopy(); } =20 #define MAX_WAIT 50 /* ms, half buffered_file limit */ @@ -2235,6 +2244,11 @@ static int ram_save_setup(QEMUFile *f, void *opaque) return -1; } } + + if ((*rsp)->free_page_support) { + balloon_free_page_start(); + } + (*rsp)->f =3D f; =20 rcu_read_lock(); @@ -2329,6 +2343,9 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) =20 ret =3D qemu_file_get_error(f); if (ret < 0) { + if (rs->ram_bulk_stage && rs->free_page_support) { + balloon_free_page_stop(); + } return ret; } =20 --=20 1.8.3.1