From patchwork Fri Jun 8 08:10:40 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Wang, Wei W" X-Patchwork-Id: 926639 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=intel.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 412G3w3wB7z9s01 for ; Fri, 8 Jun 2018 18:36:59 +1000 (AEST) Received: from localhost ([::1]:33981 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fRCtC-00066u-0B for incoming@patchwork.ozlabs.org; Fri, 08 Jun 2018 04:36:54 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46486) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fRCsY-00064E-P6 for qemu-devel@nongnu.org; Fri, 08 Jun 2018 04:36:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fRCsX-0000Q4-OZ for qemu-devel@nongnu.org; Fri, 08 Jun 2018 04:36:14 -0400 Received: from mga09.intel.com ([134.134.136.24]:58067) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fRCsX-0000OZ-EP for qemu-devel@nongnu.org; Fri, 08 Jun 2018 04:36:13 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Jun 2018 01:36:13 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,490,1520924400"; d="scan'208";a="65356028" Received: from devel-ww.sh.intel.com ([10.239.48.110]) by orsmga002.jf.intel.com with ESMTP; 08 Jun 2018 01:36:10 -0700 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, 8 Jun 2018 16:10:40 +0800 Message-Id: <1528445443-43406-4-git-send-email-wei.w.wang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1528445443-43406-1-git-send-email-wei.w.wang@intel.com> References: <1528445443-43406-1-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: 134.134.136.24 Subject: [Qemu-devel] [PATCH v8 3/6] migration: API to clear bits of guest free pages from the dirty bitmap 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, peterx@redhat.com, wei.w.wang@intel.com, pbonzini@redhat.com, nilal@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This patch adds an API to clear bits corresponding to guest free pages from the dirty bitmap. Spilt the free page block if it crosses the QEMU RAMBlock boundary. Signed-off-by: Wei Wang CC: Dr. David Alan Gilbert CC: Juan Quintela CC: Michael S. Tsirkin CC: Peter Xu --- include/migration/misc.h | 2 ++ migration/migration.c | 2 +- migration/migration.h | 1 + migration/ram.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 52 insertions(+), 1 deletion(-) diff --git a/include/migration/misc.h b/include/migration/misc.h index 4ebf24c..113320e 100644 --- a/include/migration/misc.h +++ b/include/migration/misc.h @@ -14,11 +14,13 @@ #ifndef MIGRATION_MISC_H #define MIGRATION_MISC_H +#include "exec/cpu-common.h" #include "qemu/notify.h" /* migration/ram.c */ void ram_mig_init(void); +void qemu_guest_free_page_hint(void *addr, size_t len); /* migration/block.c */ diff --git a/migration/migration.c b/migration/migration.c index 05aec2c..220ff48 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -647,7 +647,7 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp) * Return true if we're already in the middle of a migration * (i.e. any of the active or setup states) */ -static bool migration_is_setup_or_active(int state) +bool migration_is_setup_or_active(int state) { switch (state) { case MIGRATION_STATUS_ACTIVE: diff --git a/migration/migration.h b/migration/migration.h index 8f0c821..5a74740 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -230,6 +230,7 @@ void migrate_fd_error(MigrationState *s, const Error *error); void migrate_fd_connect(MigrationState *s, Error *error_in); void migrate_init(MigrationState *s); +bool migration_is_setup_or_active(int state); bool migration_is_blocked(Error **errp); /* True if outgoing migration has entered postcopy phase */ bool migration_in_postcopy(void); diff --git a/migration/ram.c b/migration/ram.c index 2eabbe9..237f11e 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2530,6 +2530,54 @@ static void ram_state_resume_prepare(RAMState *rs, QEMUFile *out) } /* + * This function clears bits of the free pages reported by the caller from the + * migration dirty bitmap. @addr is the host address corresponding to the + * start of the continuous guest free pages, and @len is the total bytes of + * those pages. + */ +void qemu_guest_free_page_hint(void *addr, size_t len) +{ + RAMBlock *block; + ram_addr_t offset; + size_t used_len, start, npages; + MigrationState *s = migrate_get_current(); + + /* This function is currently expected to be used during live migration */ + if (!migration_is_setup_or_active(s->state)) { + return; + } + + for (; len > 0; len -= used_len) { + block = qemu_ram_block_from_host(addr, false, &offset); + assert(block); + + /* + * This handles the case that the RAMBlock is resized after the free + * page hint is reported. + */ + if (unlikely(offset > block->used_length)) { + return; + } + + if (len <= block->used_length - offset) { + used_len = len; + } else { + used_len = block->used_length - offset; + addr += used_len; + } + + start = offset >> TARGET_PAGE_BITS; + npages = used_len >> TARGET_PAGE_BITS; + + qemu_mutex_lock(&ram_state->bitmap_mutex); + ram_state->migration_dirty_pages -= + bitmap_count_one_with_offset(block->bmap, start, npages); + bitmap_clear(block->bmap, start, npages); + qemu_mutex_unlock(&ram_state->bitmap_mutex); + } +} + +/* * Each of ram_save_setup, ram_save_iterate and ram_save_complete has * long-running RCU critical section. When rcu-reclaims in the code * start to become numerous it will be necessary to reduce the