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: 10453975 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 25BC060159 for ; Fri, 8 Jun 2018 08:37:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 10B4529481 for ; Fri, 8 Jun 2018 08:37:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0541929485; Fri, 8 Jun 2018 08:37:34 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6490B29481 for ; Fri, 8 Jun 2018 08:37:33 +0000 (UTC) Received: from localhost ([::1]:33985 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fRCto-0006wu-6Q for patchwork-qemu-devel@patchwork.kernel.org; Fri, 08 Jun 2018 04:37:32 -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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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