From patchwork Wed Jul 7 19:32:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eduardo Habkost X-Patchwork-Id: 1501987 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=CceHdhrR; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4GKqRh36Gxz9sW8 for ; Thu, 8 Jul 2021 05:36:32 +1000 (AEST) Received: from localhost ([::1]:39302 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m1DLS-0007IH-39 for incoming@patchwork.ozlabs.org; Wed, 07 Jul 2021 15:36:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45510) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m1DJp-0004z4-VC for qemu-devel@nongnu.org; Wed, 07 Jul 2021 15:34:49 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:47169) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m1DJn-0007pT-V7 for qemu-devel@nongnu.org; Wed, 07 Jul 2021 15:34:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625686487; 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=TUlkG2qHARb3AwaZ4WyQyaPRh3qzS1d7m4+PGhzg/Ww=; b=CceHdhrRMcnBjlym1dEuDygnsA+e9ASfSSpf3637JgjUuXHZ2VongeiMllSfwkvG9xnhwT poaEp2yfrn2nxL5hGQ0SFzahoVIyq/joEOiLf8xgsgEYXWR4JQcsxsib0YANuPNYA2Aavh JkJi9XwEUF6+PWgxx890EdWaPEEf9pc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-165-BQbVVz3WO1-Iti3l1MJMIQ-1; Wed, 07 Jul 2021 15:34:46 -0400 X-MC-Unique: BQbVVz3WO1-Iti3l1MJMIQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 62EE610B7464; Wed, 7 Jul 2021 19:34:44 +0000 (UTC) Received: from localhost (ovpn-113-79.rdu2.redhat.com [10.10.113.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id A38735C1C2; Wed, 7 Jul 2021 19:34:27 +0000 (UTC) From: Eduardo Habkost To: Peter Maydell , qemu-devel@nongnu.org Subject: [PULL 13/15] softmmu/physmem: Extend ram_block_discard_(require|disable) by two discard types Date: Wed, 7 Jul 2021 15:32:39 -0400 Message-Id: <20210707193241.2659335-14-ehabkost@redhat.com> In-Reply-To: <20210707193241.2659335-1-ehabkost@redhat.com> References: <20210707193241.2659335-1-ehabkost@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=ehabkost@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=ehabkost@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.439, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , Eduardo Habkost , "Michael S . Tsirkin" , David Hildenbrand , Alex Williamson , Peter Xu , "Dr . David Alan Gilbert" , Auger Eric , Pankaj Gupta , teawater , Igor Mammedov , Paolo Bonzini , Marek Kedzierski , Wei Yang Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: David Hildenbrand We want to separate the two cases whereby we discard ram - uncoordinated: e.g., virito-balloon - coordinated: e.g., virtio-mem coordinated via the RamDiscardManager Reviewed-by: Pankaj Gupta Acked-by: Michael S. Tsirkin Cc: Paolo Bonzini Cc: "Michael S. Tsirkin" Cc: Alex Williamson Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Cc: Peter Xu Cc: Auger Eric Cc: Wei Yang Cc: teawater Cc: Marek Kedzierski Signed-off-by: David Hildenbrand Message-Id: <20210413095531.25603-12-david@redhat.com> Signed-off-by: Eduardo Habkost --- include/exec/memory.h | 18 +++++++++++++-- softmmu/physmem.c | 54 ++++++++++++++++++++++++++++++++++++++----- 2 files changed, 64 insertions(+), 8 deletions(-) diff --git a/include/exec/memory.h b/include/exec/memory.h index a23487fdb30..87357a724aa 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -2893,6 +2893,12 @@ static inline MemOp devend_memop(enum device_endian end) */ int ram_block_discard_disable(bool state); +/* + * See ram_block_discard_disable(): only disable uncoordinated discards, + * keeping coordinated discards (via the RamDiscardManager) enabled. + */ +int ram_block_uncoordinated_discard_disable(bool state); + /* * Inhibit technologies that disable discarding of pages in RAM blocks. * @@ -2902,12 +2908,20 @@ int ram_block_discard_disable(bool state); int ram_block_discard_require(bool state); /* - * Test if discarding of memory in ram blocks is disabled. + * See ram_block_discard_require(): only inhibit technologies that disable + * uncoordinated discarding of pages in RAM blocks, allowing co-existance with + * technologies that only inhibit uncoordinated discards (via the + * RamDiscardManager). + */ +int ram_block_coordinated_discard_require(bool state); + +/* + * Test if any discarding of memory in ram blocks is disabled. */ bool ram_block_discard_is_disabled(void); /* - * Test if discarding of memory in ram blocks is required to work reliably. + * Test if any discarding of memory in ram blocks is required to work reliably. */ bool ram_block_discard_is_required(void); diff --git a/softmmu/physmem.c b/softmmu/physmem.c index f1275b61f84..3c1912a1a07 100644 --- a/softmmu/physmem.c +++ b/softmmu/physmem.c @@ -3684,8 +3684,14 @@ void mtree_print_dispatch(AddressSpaceDispatch *d, MemoryRegion *root) } } +/* Require any discards to work. */ static unsigned int ram_block_discard_required_cnt; +/* Require only coordinated discards to work. */ +static unsigned int ram_block_coordinated_discard_required_cnt; +/* Disable any discards. */ static unsigned int ram_block_discard_disabled_cnt; +/* Disable only uncoordinated discards. */ +static unsigned int ram_block_uncoordinated_discard_disabled_cnt; static QemuMutex ram_block_discard_disable_mutex; static void ram_block_discard_disable_mutex_lock(void) @@ -3711,10 +3717,27 @@ int ram_block_discard_disable(bool state) ram_block_discard_disable_mutex_lock(); if (!state) { ram_block_discard_disabled_cnt--; - } else if (!ram_block_discard_required_cnt) { - ram_block_discard_disabled_cnt++; + } else if (ram_block_discard_required_cnt || + ram_block_coordinated_discard_required_cnt) { + ret = -EBUSY; } else { + ram_block_discard_disabled_cnt++; + } + ram_block_discard_disable_mutex_unlock(); + return ret; +} + +int ram_block_uncoordinated_discard_disable(bool state) +{ + int ret = 0; + + ram_block_discard_disable_mutex_lock(); + if (!state) { + ram_block_uncoordinated_discard_disabled_cnt--; + } else if (ram_block_discard_required_cnt) { ret = -EBUSY; + } else { + ram_block_uncoordinated_discard_disabled_cnt++; } ram_block_discard_disable_mutex_unlock(); return ret; @@ -3727,10 +3750,27 @@ int ram_block_discard_require(bool state) ram_block_discard_disable_mutex_lock(); if (!state) { ram_block_discard_required_cnt--; - } else if (!ram_block_discard_disabled_cnt) { - ram_block_discard_required_cnt++; + } else if (ram_block_discard_disabled_cnt || + ram_block_uncoordinated_discard_disabled_cnt) { + ret = -EBUSY; } else { + ram_block_discard_required_cnt++; + } + ram_block_discard_disable_mutex_unlock(); + return ret; +} + +int ram_block_coordinated_discard_require(bool state) +{ + int ret = 0; + + ram_block_discard_disable_mutex_lock(); + if (!state) { + ram_block_coordinated_discard_required_cnt--; + } else if (ram_block_discard_disabled_cnt) { ret = -EBUSY; + } else { + ram_block_coordinated_discard_required_cnt++; } ram_block_discard_disable_mutex_unlock(); return ret; @@ -3738,10 +3778,12 @@ int ram_block_discard_require(bool state) bool ram_block_discard_is_disabled(void) { - return qatomic_read(&ram_block_discard_disabled_cnt); + return qatomic_read(&ram_block_discard_disabled_cnt) || + qatomic_read(&ram_block_uncoordinated_discard_disabled_cnt); } bool ram_block_discard_is_required(void) { - return qatomic_read(&ram_block_discard_required_cnt); + return qatomic_read(&ram_block_discard_required_cnt) || + qatomic_read(&ram_block_coordinated_discard_required_cnt); }