From nobody Mon Feb 9 08:57:08 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; 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=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1643299118439313.14878652963614; Thu, 27 Jan 2022 07:58:38 -0800 (PST) Received: from localhost ([::1]:44184 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nD7AT-0007s5-EN for importer@patchew.org; Thu, 27 Jan 2022 10:58:37 -0500 Received: from eggs.gnu.org ([209.51.188.92]:42686) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nD6bD-0007xf-4A for qemu-devel@nongnu.org; Thu, 27 Jan 2022 10:22:11 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:52045) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nD6bA-0004MS-0a for qemu-devel@nongnu.org; Thu, 27 Jan 2022 10:22:10 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-169-4ZS-J2K4OuKKFo7Le3NPLA-1; Thu, 27 Jan 2022 10:22:04 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1C83A83DD23; Thu, 27 Jan 2022 15:22:01 +0000 (UTC) Received: from secure.mitica (unknown [10.39.194.185]) by smtp.corp.redhat.com (Postfix) with ESMTP id E297F70D4A; Thu, 27 Jan 2022 15:21:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643296927; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NS9i5KtB9MDi6NvLNSXtcUhnOuwhJtpHaixEEDN6Yyo=; b=XeSPfFmj1dFUoxiaVQMC6JEJdiZ5NlKIT0p93a5JQgJiUdS/b99146w+87wujdRtmkpbSw WnaEkYo6vjGBCt5OGoOw3CIA8y9kxWMeaIOIVj1mUB9ONp4yKcZd3kzpynJpg6CGe45Skt Xoi5YS3kJuL4f9ap3sVD7a4Lozjo5qo= X-MC-Unique: 4ZS-J2K4OuKKFo7Le3NPLA-1 From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PULL 37/38] migration: Simplify unqueue_page() Date: Thu, 27 Jan 2022 16:05:47 +0100 Message-Id: <20220127150548.20595-38-quintela@redhat.com> In-Reply-To: <20220127150548.20595-1-quintela@redhat.com> References: <20220127150548.20595-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=quintela@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com 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=170.10.129.124; envelope-from=quintela@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.159, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URG_BIZ=0.573 autolearn=unavailable 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: , Cc: Fam Zheng , Peter Maydell , "Michael S. Tsirkin" , Jason Wang , Mark Cave-Ayland , Peter Xu , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Gerd Hoffmann , Ani Sinha , "Edgar E. Iglesias" , Eric Blake , Hannes Reinecke , Vikram Garhwal , qemu-block@nongnu.org, Juan Quintela , Daniel Henrique Barboza , Markus Armbruster , Artyom Tarasenko , Pavel Pisa , Alistair Francis , "Dr. David Alan Gilbert" , Greg Kurz , qemu-arm@nongnu.org, =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Paolo Bonzini , Stafford Horne , David Gibson , Laurent Vivier , Andrew Baumann , qemu-ppc@nongnu.org, Igor Mammedov , Aurelien Jarno Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1643299121316100001 Content-Type: text/plain; charset="utf-8" From: Peter Xu This patch simplifies unqueue_page() on both sides of it (itself, and calle= r). Firstly, due to the fact that right after unqueue_page() returned true, we'= ll definitely send a huge page (see ram_save_huge_page() call - it will _never_ exit before finish sending that huge page), so unqueue_page() does not need= to jump in small page size if huge page is enabled on the ramblock. IOW, it's destined that only the 1st 4K page will be valid, when unqueue the 2nd+ time we'll notice the whole huge page has already been sent anyway. Switching to operating on huge page reduces a lot of the loops of redundant unqueue_page= (). Meanwhile, drop the dirty check. It's not helpful to call test_bit() every time to jump over clean pages, as ram_save_host_page() has already done so, while in a faster way (see commit ba1b7c812c ("migration/ram: Optimize ram_save_host_page()", 2021-05-13)). So that's not necessary too. Drop the two tracepoints along the way - based on above analysis it's very possible that no one is really using it.. Signed-off-by: Peter Xu Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/ram.c | 37 +++++++++++-------------------------- migration/trace-events | 3 +-- 2 files changed, 12 insertions(+), 28 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index eb9db4f777..91ca743ac8 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1547,6 +1547,7 @@ static RAMBlock *unqueue_page(RAMState *rs, ram_addr_= t *offset) { struct RAMSrcPageRequest *entry; RAMBlock *block =3D NULL; + size_t page_size; =20 if (!postcopy_has_request(rs)) { return NULL; @@ -1563,10 +1564,13 @@ static RAMBlock *unqueue_page(RAMState *rs, ram_add= r_t *offset) entry =3D QSIMPLEQ_FIRST(&rs->src_page_requests); block =3D entry->rb; *offset =3D entry->offset; + page_size =3D qemu_ram_pagesize(block); + /* Each page request should only be multiple page size of the ramblock= */ + assert((entry->len % page_size) =3D=3D 0); =20 - if (entry->len > TARGET_PAGE_SIZE) { - entry->len -=3D TARGET_PAGE_SIZE; - entry->offset +=3D TARGET_PAGE_SIZE; + if (entry->len > page_size) { + entry->len -=3D page_size; + entry->offset +=3D page_size; } else { memory_region_unref(block->mr); QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req); @@ -1574,6 +1578,9 @@ static RAMBlock *unqueue_page(RAMState *rs, ram_addr_= t *offset) migration_consume_urgent_request(); } =20 + trace_unqueue_page(block->idstr, *offset, + test_bit((*offset >> TARGET_PAGE_BITS), block->bmap= )); + return block; } =20 @@ -1948,30 +1955,8 @@ static bool get_queued_page(RAMState *rs, PageSearch= Status *pss) { RAMBlock *block; ram_addr_t offset; - bool dirty; =20 - do { - block =3D unqueue_page(rs, &offset); - /* - * We're sending this page, and since it's postcopy nothing else - * will dirty it, and we must make sure it doesn't get sent again - * even if this queue request was received after the background - * search already sent it. - */ - if (block) { - unsigned long page; - - page =3D offset >> TARGET_PAGE_BITS; - dirty =3D test_bit(page, block->bmap); - if (!dirty) { - trace_get_queued_page_not_dirty(block->idstr, (uint64_t)of= fset, - page); - } else { - trace_get_queued_page(block->idstr, (uint64_t)offset, page= ); - } - } - - } while (block && !dirty); + block =3D unqueue_page(rs, &offset); =20 if (!block) { /* diff --git a/migration/trace-events b/migration/trace-events index 171a83a55d..48aa7b10ee 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -86,8 +86,6 @@ put_qlist_end(const char *field_name, const char *vmsd_na= me) "%s(%s)" qemu_file_fclose(void) "" =20 # ram.c -get_queued_page(const char *block_name, uint64_t tmp_offset, unsigned long= page_abs) "%s/0x%" PRIx64 " page_abs=3D0x%lx" -get_queued_page_not_dirty(const char *block_name, uint64_t tmp_offset, uns= igned long page_abs) "%s/0x%" PRIx64 " page_abs=3D0x%lx" 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" @@ -113,6 +111,7 @@ ram_save_iterate_big_wait(uint64_t milliconds, int iter= ations) "big wait: %" PRI ram_load_complete(int ret, uint64_t seq_iter) "exit_code %d seq iteration = %" PRIu64 ram_write_tracking_ramblock_start(const char *block_id, size_t page_size, = void *addr, size_t length) "%s: page_size: %zu addr: %p length: %zu" ram_write_tracking_ramblock_stop(const char *block_id, size_t page_size, v= oid *addr, size_t length) "%s: page_size: %zu addr: %p length: %zu" +unqueue_page(char *block, uint64_t offset, bool dirty) "ramblock '%s' offs= et 0x%"PRIx64" dirty %d" =20 # multifd.c multifd_new_send_channel_async(uint8_t id) "channel %u" --=20 2.34.1