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bh=NDJl84KEdjlgLLvcRzDOsHL+HtcoP4SkwFsxAmiKiRE=; b=H+GPGPfQc4LtiChm1d/bKJyfCasJi+JqCkkAzTp7bEbCtPbR6AnAfDLAx/tnUDw6Y+RNLK yCIRPtUbjKSxBGl+mwHK46MCQGiHU4RsssGtmv9O3UcWj2ybhD6kHs9gDTX5tb0il4P4u2 hM9jF7cnrQmzipcIpgEHh1l8Cyo4UZ8= X-MC-Unique: 85M06svQPa6vO3QCzX-uUA-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v4 09/11] softmmu/physmem: Extend ram_block_discard_(require|disable) by two discard types Date: Thu, 7 Jan 2021 14:34:21 +0100 Message-Id: <20210107133423.44964-10-david@redhat.com> In-Reply-To: <20210107133423.44964-1-david@redhat.com> References: <20210107133423.44964-1-david@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=david@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=63.128.21.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.246, 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: Marek Kedzierski , Pankaj Gupta , Wei Yang , David Hildenbrand , "Michael S. Tsirkin" , Alex Williamson , Peter Xu , "Dr . David Alan Gilbert" , Auger Eric , Pankaj Gupta , teawater , Jonathan Cameron , Paolo Bonzini , Igor Mammedov Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" We want to separate the two cases whereby we discard ram - uncoordinated: e.g., virito-balloon - coordinated: e.g., virtio-mem coordinated via the RamDiscardMgr Reviewed-by: Pankaj Gupta 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 --- 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 67d9f1f3a7..11832cce3c 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -2808,6 +2808,12 @@ static inline MemOp devend_memop(enum device_endian = end) */ int ram_block_discard_disable(bool state); =20 +/* + * See ram_block_discard_disable(): only disable uncoordinated discards, + * keeping coordinated discards (via the RamDiscardMgr) enabled. + */ +int ram_block_uncoordinated_discard_disable(bool state); + /* * Inhibit technologies that disable discarding of pages in RAM blocks. * @@ -2817,12 +2823,20 @@ int ram_block_discard_disable(bool state); int ram_block_discard_require(bool state); =20 /* - * 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 + * RamDiscardMgr). + */ +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); =20 /* - * 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 reli= ably. */ bool ram_block_discard_is_required(void); =20 diff --git a/softmmu/physmem.c b/softmmu/physmem.c index dc61335b60..2e8512aa26 100644 --- a/softmmu/physmem.c +++ b/softmmu/physmem.c @@ -3660,8 +3660,14 @@ void mtree_print_dispatch(AddressSpaceDispatch *d, M= emoryRegion *root) } } =20 +/* Require any discards to work. */ static unsigned int ram_block_discard_requirers; +/* Require only coordinated discards to work. */ +static unsigned int ram_block_coordinated_discard_requirers; +/* Disable any discards. */ static unsigned int ram_block_discard_disablers; +/* Disable only uncoordinated discards. */ +static unsigned int ram_block_uncoordinated_discard_disablers; static QemuMutex ram_block_discard_disable_mutex; =20 static void ram_block_discard_disable_mutex_lock(void) @@ -3687,10 +3693,27 @@ int ram_block_discard_disable(bool state) ram_block_discard_disable_mutex_lock(); if (!state) { ram_block_discard_disablers--; - } else if (!ram_block_discard_requirers) { - ram_block_discard_disablers++; + } else if (ram_block_discard_requirers || + ram_block_coordinated_discard_requirers) { + ret =3D -EBUSY; } else { + ram_block_discard_disablers++; + } + ram_block_discard_disable_mutex_unlock(); + return ret; +} + +int ram_block_uncoordinated_discard_disable(bool state) +{ + int ret =3D 0; + + ram_block_discard_disable_mutex_lock(); + if (!state) { + ram_block_uncoordinated_discard_disablers--; + } else if (ram_block_discard_requirers) { ret =3D -EBUSY; + } else { + ram_block_uncoordinated_discard_disablers++; } ram_block_discard_disable_mutex_unlock(); return ret; @@ -3703,10 +3726,27 @@ int ram_block_discard_require(bool state) ram_block_discard_disable_mutex_lock(); if (!state) { ram_block_discard_requirers--; - } else if (!ram_block_discard_disablers) { - ram_block_discard_requirers++; + } else if (ram_block_discard_disablers || + ram_block_uncoordinated_discard_disablers) { + ret =3D -EBUSY; } else { + ram_block_discard_requirers++; + } + ram_block_discard_disable_mutex_unlock(); + return ret; +} + +int ram_block_coordinated_discard_require(bool state) +{ + int ret =3D 0; + + ram_block_discard_disable_mutex_lock(); + if (!state) { + ram_block_coordinated_discard_requirers--; + } else if (ram_block_discard_disablers) { ret =3D -EBUSY; + } else { + ram_block_coordinated_discard_requirers++; } ram_block_discard_disable_mutex_unlock(); return ret; @@ -3714,10 +3754,12 @@ int ram_block_discard_require(bool state) =20 bool ram_block_discard_is_disabled(void) { - return qatomic_read(&ram_block_discard_disablers); + return qatomic_read(&ram_block_discard_disablers) || + qatomic_read(&ram_block_uncoordinated_discard_disablers); } =20 bool ram_block_discard_is_required(void) { - return qatomic_read(&ram_block_discard_requirers); + return qatomic_read(&ram_block_discard_requirers) || + qatomic_read(&ram_block_coordinated_discard_requirers); } --=20 2.29.2