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2022-07-20migration: Enable TLS for preempt channelPeter Xu
This patch is based on the async preempt channel creation. It continues wiring up the new channel with TLS handshake to destionation when enabled. Note that only the src QEMU needs such operation; the dest QEMU does not need any change for TLS support due to the fact that all channels are established synchronously there, so all the TLS magic is already properly handled by migration_tls_channel_process_incoming(). Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220707185518.27529-1-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20migration: Create the postcopy preempt channel asynchronouslyPeter Xu
This patch allows the postcopy preempt channel to be created asynchronously. The benefit is that when the connection is slow, we won't take the BQL (and potentially block all things like QMP) for a long time without releasing. A function postcopy_preempt_wait_channel() is introduced, allowing the migration thread to be able to wait on the channel creation. The channel is always created by the main thread, in which we'll kick a new semaphore to tell the migration thread that the channel has created. We'll need to wait for the new channel in two places: (1) when there's a new postcopy migration that is starting, or (2) when there's a postcopy migration to resume. For the start of migration, we don't need to wait for this channel until when we want to start postcopy, aka, postcopy_start(). We'll fail the migration if we found that the channel creation failed (which should probably not happen at all in 99% of the cases, because the main channel is using the same network topology). For a postcopy recovery, we'll need to wait in postcopy_pause(). In that case if the channel creation failed, we can't fail the migration or we'll crash the VM, instead we keep in PAUSED state, waiting for yet another recovery. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Manish Mishra <manish.mishra@nutanix.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220707185509.27311-1-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20migration: Postcopy recover with preempt enabledPeter Xu
To allow postcopy recovery, the ram fast load (preempt-only) dest QEMU thread needs similar handling on fault tolerance. When ram_load_postcopy() fails, instead of stopping the thread it halts with a semaphore, preparing to be kicked again when recovery is detected. A mutex is introduced to make sure there's no concurrent operation upon the socket. To make it simple, the fast ram load thread will take the mutex during its whole procedure, and only release it if it's paused. The fast-path socket will be properly released by the main loading thread safely when there's network failures during postcopy with that mutex held. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220707185506.27257-1-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20migration: Postcopy preemption preparation on channel creationPeter Xu
Create a new socket for postcopy to be prepared to send postcopy requested pages via this specific channel, so as to not get blocked by precopy pages. A new thread is also created on dest qemu to receive data from this new channel based on the ram_load_postcopy() routine. The ram_load_postcopy(POSTCOPY) branch and the thread has not started to function, and that'll be done in follow up patches. Cleanup the new sockets on both src/dst QEMUs, meanwhile look after the new thread too to make sure it'll be recycled properly. Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220707185502.27149-1-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> dgilbert: With Peter's fix to quieten compiler warning on start_migration
2022-04-06Replace qemu_real_host_page variables with inlined functionsMarc-André Lureau
Replace the global variables with inlined helper functions. getpagesize() is very likely annotated with a "const" function attribute (at least with glibc), and thus optimization should apply even better. This avoids the need for a constructor initialization too. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-02migration: postcopy_pause_fault_thread() never failsPeter Xu
Per the title, remove the return code and simplify the callers as the errors will never be triggered. No functional change intended. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220301083925.33483-12-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-03-02migration: Enlarge postcopy recovery to capture !-EIO tooPeter Xu
We used to have quite a few places making sure -EIO happened and that's the only way to trigger postcopy recovery. That's based on the assumption that we'll only return -EIO for channel issues. It'll work in 99.99% cases but logically that won't cover some corner cases. One example is e.g. ram_block_from_stream() could fail with an interrupted network, then -EINVAL will be returned instead of -EIO. I remembered Dave Gilbert pointed that out before, but somehow this is overlooked. Neither did I encounter anything outside the -EIO error. However we'd better touch that up before it triggers a rare VM data loss during live migrating. To cover as much those cases as possible, remove the -EIO restriction on triggering the postcopy recovery, because even if it's not a channel failure, we can't do anything better than halting QEMU anyway - the corpse of the process may even be used by a good hand to dig out useful memory regions, or the admin could simply kill the process later on. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220301083925.33483-11-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-03-02migration: Add postcopy_thread_create()Peter Xu
Postcopy create threads. A common manner is we init a sem and use it to sync with the thread. Namely, we have fault_thread_sem and listen_thread_sem and they're only used for this. Make it a shared infrastructure so it's easier to create yet another thread. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220301083925.33483-7-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-03-02migration: Introduce postcopy channels on dest nodePeter Xu
Postcopy handles huge pages in a special way that currently we can only have one "channel" to transfer the page. It's because when we install pages using UFFDIO_COPY, we need to have the whole huge page ready, it also means we need to have a temp huge page when trying to receive the whole content of the page. Currently all maintainance around this tmp page is global: firstly we'll allocate a temp huge page, then we maintain its status mostly within ram_load_postcopy(). To enable multiple channels for postcopy, the first thing we need to do is to prepare N temp huge pages as caching, one for each channel. Meanwhile we need to maintain the tmp huge page status per-channel too. To give some example, some local variables maintained in ram_load_postcopy() are listed; they are responsible for maintaining temp huge page status: - all_zero: this keeps whether this huge page contains all zeros - target_pages: this counts how many target pages have been copied - host_page: this keeps the host ptr for the page to install Move all these fields to be together with the temp huge pages to form a new structure called PostcopyTmpPage. Then for each (future) postcopy channel, we need one structure to keep the state around. For vanilla postcopy, obviously there's only one channel. It contains both precopy and postcopy pages. This patch teaches the dest migration node to start realize the possible number of postcopy channels by introducing the "postcopy_channels" variable. Its value is calculated when setup postcopy on dest node (during POSTCOPY_LISTEN phase). Vanilla postcopy will have channels=1, but when postcopy-preempt capability is enabled (in the future), we will boost it to 2 because even during partial sending of a precopy huge page we still want to preempt it and start sending the postcopy requested page right away (so we start to keep two temp huge pages; more if we want to enable multifd). In this patch there's a TODO marked for that; so far the channels is always set to 1. We need to send one "host huge page" on one channel only and we cannot split them, because otherwise the data upon the same huge page can locate on more than one channel so we need more complicated logic to manage. One temp host huge page for each channel will be enough for us for now. Postcopy will still always use the index=0 huge page even after this patch. However it prepares for the latter patches where it can start to use multiple channels (which needs src intervention, because only src knows which channel we should use). Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20220301083925.33483-5-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> dgilbert: Fixed up long line
2022-02-21include: Move qemu_madvise() and related #defines to new qemu/madvise.hPeter Maydell
The function qemu_madvise() and the QEMU_MADV_* constants associated with it are used in only 10 files. Move them out of osdep.h to a new qemu/madvise.h header that is included where it is needed. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20220208200856.3558249-2-peter.maydell@linaro.org
2022-01-28migration: Move temp page setup and cleanup into separate functionsPeter Xu
Temp pages will need to grow if we want to have multiple channels for postcopy, because each channel will need its own temp page to cache huge page data. Before doing that, cleanup the related code. No functional change intended. Since at it, touch up the errno handling a little bit on the setup side. Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-01-28migration: Enable UFFD_FEATURE_THREAD_ID even without blocktime featPeter Xu
This patch allows us to read the tid even without blocktime feature enabled. It's useful when tracing postcopy fault thread on faulted pages to show thread id too with the address. Remove the comments - they're merely not helpful at all. Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-06migration: Check that postcopy fd's are not NULLJuan Quintela
If postcopy has finished, it frees the array. But vhost-user unregister it at cleanup time. fixes: c4f7538 Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-11-01migration: Simplify alignment and alignment checksDavid Hildenbrand
Let's use QEMU_ALIGN_DOWN() and friends to make the code a bit easier to read. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-01migration/postcopy: Handle RAMBlocks with a RamDiscardManager on the destinationDavid Hildenbrand
Currently, when someone (i.e., the VM) accesses discarded parts inside a RAMBlock with a RamDiscardManager managing the corresponding mapped memory region, postcopy will request migration of the corresponding page from the source. The source, however, will never answer, because it refuses to migrate such pages with undefined content ("logically unplugged"): the pages are never dirty, and get_queued_page() will consequently skip processing these postcopy requests. Especially reading discarded ("logically unplugged") ranges is supposed to work in some setups (for example with current virtio-mem), although it barely ever happens: still, not placing a page would currently stall the VM, as it cannot make forward progress. Let's check the state via the RamDiscardManager (the state e.g., of virtio-mem is migrated during precopy) and avoid sending a request that will never get answered. Place a fresh zero page instead to keep the VM working. This is the same behavior that would happen automatically without userfaultfd being active, when accessing virtual memory regions without populated pages -- "populate on demand". For now, there are valid cases (as documented in the virtio-mem spec) where a VM might read discarded memory; in the future, we will disallow that. Then, we might want to handle that case differently, e.g., warning the user that the VM seems to be mis-behaving. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-05-13migration/ram: Handle RAM block resizes during postcopyDavid Hildenbrand
Resizing while migrating is dangerous and does not work as expected. The whole migration code works with the usable_length of a ram block and does not expect this value to change at random points in time. In the case of postcopy, relying on used_length is racy as soon as the guest is running. Also, when used_length changes we might leave the uffd handler registered for some memory regions, reject valid pages when migrating and fail when sending the recv bitmap to the source. Resizing can be trigger *after* (but not during) a reset in ACPI code by the guest - hw/arm/virt-acpi-build.c:acpi_ram_update() - hw/i386/acpi-build.c:acpi_ram_update() Let's remember the original used_length in a separate variable and use it in relevant postcopy code. Make sure to update it when we resize during precopy, when synchronizing the RAM block sizes with the source. Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20210429112708.12291-9-david@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-12-19qapi: Use QAPI_LIST_PREPEND() where possibleEric Blake
Anywhere we create a list of just one item or by prepending items (typically because order doesn't matter), we can use QAPI_LIST_PREPEND(). But places where we must keep the list in order by appending remain open-coded until later patches. Note that as a side effect, this also performs a cleanup of two minor issues in qga/commands-posix.c: the old code was performing new = g_malloc0(sizeof(*ret)); which 1) is confusing because you have to verify whether 'new' and 'ret' are variables with the same type, and 2) would conflict with C++ compilation (not an actual problem for this file, but makes copy-and-paste harder). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20201113011340.463563-5-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> [Straightforward conflicts due to commit a8aa94b5f8 "qga: update schema for guest-get-disks 'dependents' field" and commit a10b453a52 "target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c" resolved. Commit message tweaked.] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-11-02migration: Unify reset of last_rb on destination node when recoverPeter Xu
When postcopy recover happens, we need to reset last_rb after each return of postcopy_pause_fault_thread() because that means we just got the postcopy migration continued. Unify this reset to the place right before we want to kick the fault thread again, when we get the command MIG_CMD_POSTCOPY_RESUME from source. This is actually more than that - because the main thread on destination will now be able to call migrate_send_rp_req_pages_pending() too, so the fault thread is not the only user of last_rb now. Move the reset earlier will allow the first call to migrate_send_rp_req_pages_pending() to use the reset value even if called from the main thread. (NOTE: this is not a real fix to 0c26781c09 mentioned below, however it is just a mark that when picking up 0c26781c09 we'd better have this one too; the real fix will come later) Fixes: 0c26781c09 ("migration: Sync requested pages after postcopy recovery") Tested-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20201102153010.11979-2-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26migration: Maintain postcopy faulted addressesPeter Xu
Maintain a list of faulted addresses on the destination host for which we're waiting on. This is implemented using a GTree rather than a real list to make sure even there're plenty of vCPUs/threads that are faulting, the lookup will still be fast with O(log(N)) (because we'll do that after placing each page). It should bring a slight overhead, but ideally that shouldn't be a big problem simply because in most cases the requested page list will be short. Actually we did similar things for postcopy blocktime measurements. This patch didn't use that simply because: (1) blocktime measurement is towards vcpu threads only, but here we need to record all faulted addresses, including main thread and external thread (like, DPDK via vhost-user). (2) blocktime measurement will require UFFD_FEATURE_THREAD_ID, but here we don't want to add that extra dependency on the kernel version since not necessary. E.g., we don't need to know which thread faulted on which page, we also don't care about multiple threads faulting on the same page. But we only care about what addresses are faulted so waiting for a page copying from src. (3) blocktime measurement is not enabled by default. However we need this by default especially for postcopy recover. Another thing to mention is that this patch introduced a new mutex to serialize the receivedmap and the page_requested tree, however that serialization does not cover other procedures like UFFDIO_COPY. Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20201021212721.440373-4-peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26migration: Pass incoming state into qemu_ufd_copy_ioctl()Peter Xu
It'll be used in follow up patches to access more fields out of it. Meanwhile fetch the userfaultfd inside the function. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20201021212721.440373-2-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26migration: Add spaces around operatorBihong Yu
Signed-off-by: Bihong Yu <yubihong@huawei.com> Reviewed-by: Chuan Zheng <zhengchuan@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1603163448-27122-4-git-send-email-yubihong@huawei.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-25migration: Rework migrate_send_rp_req_pages() functionPeter Xu
We duplicated the logic of maintaining the last_rb variable at both callers of this function. Pass *rb pointer into the function so that we can avoid duplicating the logic. Also, when we have the rb pointer, it's also easier to remove the original 2nd & 4th parameters, because both of them (name of the ramblock when needed, or the page size) can be fetched from the ramblock pointer too. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20200908203022.341615-3-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-23qemu/atomic.h: rename atomic_ to qatomic_Stefan Hajnoczi
clang's C11 atomic_fetch_*() functions only take a C11 atomic type pointer argument. QEMU uses direct types (int, etc) and this causes a compiler error when a QEMU code calls these functions in a source file that also included <stdatomic.h> via a system header file: $ CC=clang CXX=clang++ ./configure ... && make ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid) Avoid using atomic_*() names in QEMU's atomic.h since that namespace is used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h and <stdatomic.h> can co-exist. I checked /usr/include on my machine and searched GitHub for existing "qatomic_" users but there seem to be none. This patch was generated using: $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \ sort -u >/tmp/changed_identifiers $ for identifier in $(</tmp/changed_identifiers); do sed -i "s%\<$identifier\>%q$identifier%g" \ $(git grep -I -l "\<$identifier\>") done I manually fixed line-wrap issues and misaligned rST tables. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
2020-09-17migration/: fix some comment spelling errorszhaolichang
I found that there are many spelling errors in the comments of qemu, so I used the spellcheck tool to check the spelling errors and finally found some spelling errors in the migration folder. Signed-off-by: zhaolichang <zhaolichang@huawei.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <20200917075029.313-3-zhaolichang@huawei.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-07-07Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into stagingPeter Maydell
virtio,acpi: features, fixes, cleanups. vdpa support virtio-mem support a handy script for disassembling acpi tables misc fixes and cleanups Signed-off-by: Michael S. Tsirkin <mst@redhat.com> # gpg: Signature made Tue 07 Jul 2020 13:00:35 BST # gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469 # gpg: issuer "mst@redhat.com" # gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full] # gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full] # Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67 # Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469 * remotes/mst/tags/for_upstream: (41 commits) vhost-vdpa: introduce vhost-vdpa net client vhost-vdpa: introduce vhost-vdpa backend vhost_net: introduce set_config & get_config vhost: implement vhost_force_iommu method vhost: introduce new VhostOps vhost_force_iommu vhost: implement vhost_vq_get_addr method vhost: introduce new VhostOps vhost_vq_get_addr vhost: implement vhost_dev_start method vhost: introduce new VhostOps vhost_dev_start vhost: check the existence of vhost_set_iotlb_callback virtio-pci: implement queue_enabled method virtio-bus: introduce queue_enabled method vhost_net: use the function qemu_get_peer net: introduce qemu_get_peer MAINTAINERS: add VT-d entry docs: vhost-user: add Virtio status protocol feature tests/acpi: remove stale allowed tables numa: Auto-enable NUMA when any memory devices are possible virtio-mem: Exclude unplugged memory during migration virtio-mem: Add trace events ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> # Conflicts: # hw/arm/virt.c # hw/virtio/trace-events
2020-07-03migration: postcopy take proper error returnDr. David Alan Gilbert
This function returns a boolean success and we're returning -1; lets just use the 'out' error path. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Fixes: 58b7c17e226 ("Disable mlock around incoming postcopy") Buglink: https://bugs.launchpad.net/qemu/+bug/1885720 Message-Id: <20200701093557.130096-1-dgilbert@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-07-02virtio-balloon: Rip out qemu_balloon_inhibit()David Hildenbrand
The only remaining special case is postcopy. It cannot handle concurrent discards yet, which would result in requesting already sent pages from the source. Special-case it in virtio-balloon instead. Introduce migration_in_incoming_postcopy(), to find out if incoming postcopy is active. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Juan Quintela <quintela@redhat.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200626072248.78761-7-david@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-26core: replace getpagesize() with qemu_real_host_page_sizeWei Yang
There are three page size in qemu: real host page size host page size target page size All of them have dedicate variable to represent. For the last two, we use the same form in the whole qemu project, while for the first one we use two forms: qemu_real_host_page_size and getpagesize(). qemu_real_host_page_size is defined to be a replacement of getpagesize(), so let it serve the role. [Note] Not fully tested for some arch or device. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Message-Id: <20191013021145.16011-3-richardw.yang@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-10-11migration/postcopy: rename postcopy_ram_enable_notify to ↵Wei Yang
postcopy_ram_incoming_setup Function postcopy_ram_incoming_setup and postcopy_ram_incoming_cleanup is a pair. Rename to make it clear for audience. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20191010011316.31363-2-richardw.yang@linux.intel.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11migration/postcopy: postpone setting PostcopyState to ENDWei Yang
There are two places to call function postcopy_ram_incoming_cleanup() postcopy_ram_listen_thread on migration success loadvm_postcopy_handle_listen one setup failure On success, the vm will never accept another migration. On failure, PostcopyState is transited from LISTENING to END and would be checked in qemu_loadvm_state_main(). If PostcopyState is RUNNING, migration would be paused and retried. Currently PostcopyState is set to END in function postcopy_ram_incoming_cleanup(). With above analysis, we can take this step out and postpone this till the end of listen thread to indicate the listen thread is done. This is a preparation patch for later cleanup. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Message-Id: <20191006000249.29926-3-richardw.yang@linux.intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Fixed up in merge to the 1 parameter postcopy_state_set
2019-10-11migration/postcopy: fix typo in mark_postcopy_blocktime_begin's commentWei Yang
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Message-Id: <20191005220517.24029-3-richardw.yang@linux.intel.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11migration/postcopy: map large zero page in postcopy_ram_incoming_setup()Wei Yang
postcopy_ram_incoming_setup() and postcopy_ram_incoming_cleanup() are counterpart. It is reasonable to map/unmap large zero page in these two functions respectively. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Message-Id: <20191005135021.21721-3-richardw.yang@linux.intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11migration/postcopy: allocate tmp_page in setup stageWei Yang
During migration, a tmp page is allocated so that we could place a whole host page during postcopy. Currently the page is allocated during load stage, this is a little bit late. And more important, if we failed to allocate it, the error is not checked properly. Even it is NULL, we would still use it. This patch moves the allocation to setup stage and if failed error message would be printed and caller would notice it. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-16Merge remote-tracking branch ↵Peter Maydell
'remotes/armbru/tags/pull-include-2019-08-13-v2' into staging Header cleanup patches for 2019-08-13 # gpg: Signature made Fri 16 Aug 2019 12:39:12 BST # gpg: using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653 # gpg: issuer "armbru@redhat.com" # gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full] # gpg: aka "Markus Armbruster <armbru@pond.sub.org>" [full] # Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653 * remotes/armbru/tags/pull-include-2019-08-13-v2: (29 commits) sysemu: Split sysemu/runstate.h off sysemu/sysemu.h sysemu: Move the VMChangeStateEntry typedef to qemu/typedefs.h Include sysemu/sysemu.h a lot less Clean up inclusion of sysemu/sysemu.h numa: Move remaining NUMA declarations from sysemu.h to numa.h Include sysemu/hostmem.h less numa: Don't include hw/boards.h into sysemu/numa.h Include hw/boards.h a bit less Include hw/qdev-properties.h less Include qemu/main-loop.h less Include qemu/queue.h slightly less Include hw/hw.h exactly where needed Include qom/object.h slightly less Include exec/memory.h slightly less Include migration/vmstate.h less migration: Move the VMStateDescription typedef to typedefs.h Clean up inclusion of exec/cpu-common.h Include hw/irq.h a lot less typedefs: Separate incomplete types and function types ide: Include hw/ide/internal a bit less outside hw/ide/ ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-08-16Include exec/memory.h slightly lessMarkus Armbruster
Drop unnecessary inclusions from headers. Downgrade a few more to exec/hwaddr.h. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20190812052359.30071-17-armbru@redhat.com>
2019-08-14migration/postcopy: make PostcopyDiscardState a static variableWei Yang
In postcopy-ram.c, we provide three functions to discard certain RAMBlock range: * postcopy_discard_send_init() * postcopy_discard_send_range() * postcopy_discard_send_finish() Currently, we allocate/deallocate PostcopyDiscardState for each RAMBlock on sending discard information to destination. This is not necessary and the same data area could be reused for each RAMBlock. This patch defines PostcopyDiscardState a static variable. By doing so: 1) avoid memory allocation and deallocation to the system 2) avoid potential failure of memory allocation 3) hide some details for their users Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Message-Id: <20190724010721.2146-1-richardw.yang@linux.intel.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-07-05general: Replace global smp variables with smp machine propertiesLike Xu
Basically, the context could get the MachineState reference via call chains or unrecommended qdev_get_machine() in !CONFIG_USER_ONLY mode. A local variable of the same name would be introduced in the declaration phase out of less effort OR replace it on the spot if it's only used once in the context. No semantic changes. Signed-off-by: Like Xu <like.xu@linux.intel.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20190518205428.90532-4-like.xu@linux.intel.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-03-06migration: Add an ability to ignore shared RAM blocksYury Kotov
If ignore-shared capability is set then skip shared RAMBlocks during the RAM migration. Also, move qemu_ram_foreach_migratable_block (and rename) to the migration code, because it requires access to the migration capabilities. Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru> Message-Id: <20190215174548.2630-4-yury-kotov@yandex-team.ru> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06exec: Change RAMBlockIterFunc definitionYury Kotov
Currently, qemu_ram_foreach_* calls RAMBlockIterFunc with many block-specific arguments. But often iter func needs RAMBlock*. This refactoring is needed for fast access to RAMBlock flags from qemu_ram_foreach_block's callback. The only way to achieve this now is to call qemu_ram_block_from_host (which also enumerates blocks). So, this patch reduces complexity of qemu_ram_foreach_block() -> cb() -> qemu_ram_block_from_host() from O(n^2) to O(n). Fix RAMBlockIterFunc definition and add some functions to read RAMBlock* fields witch were passed. Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru> Message-Id: <20190215174548.2630-2-yury-kotov@yandex-team.ru> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-01-23migration: add more error handling for postcopy_ram_enable_notifyFei Li
Call postcopy_ram_incoming_cleanup() to do the cleanup when postcopy_ram_enable_notify fails. Besides, report the error message when qemu_ram_foreach_migratable_block() fails. Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Fei Li <fli@suse.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190113140849.38339-5-lifei1214@126.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-10-11migration: Stop postcopy fault thread before notifyingIlya Maximets
POSTCOPY_NOTIFY_INBOUND_END handlers will remove userfault fds from the postcopy_remote_fds array which could be still in use by the fault thread. Let's stop the thread before notification to avoid possible accessing wrong memory. Fixes: 46343570c06e ("vhost+postcopy: Wire up POSTCOPY_END notify") Cc: qemu-stable@nongnu.org Signed-off-by: Ilya Maximets <i.maximets@samsung.com> Message-Id: <20181008160536.6332-2-i.maximets@samsung.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-08-25Merge remote-tracking branch 'remotes/awilliam/tags/vfio-fixes-20180823.1' ↵Peter Maydell
into staging VFIO fixes 2018-08-23 - Fix coverity reported issue with use of realpath (Alex Williamson) - Cleanup file descriptor in error path (Alex Williamson) - Fix postcopy use of new balloon inhibitor (Alex Williamson) # gpg: Signature made Thu 23 Aug 2018 17:46:41 BST # gpg: using RSA key 239B9B6E3BB08B22 # gpg: Good signature from "Alex Williamson <alex.williamson@redhat.com>" # gpg: aka "Alex Williamson <alex@shazbot.org>" # gpg: aka "Alex Williamson <alwillia@redhat.com>" # gpg: aka "Alex Williamson <alex.l.williamson@gmail.com>" # Primary key fingerprint: 42F6 C04E 540B D1A9 9E7B 8A90 239B 9B6E 3BB0 8B22 * remotes/awilliam/tags/vfio-fixes-20180823.1: postcopy: Synchronize usage of the balloon inhibitor vfio/pci: Fix failure to close file descriptor on error vfio/pci: Handle subsystem realpath() returning NULL Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-23postcopy: Synchronize usage of the balloon inhibitorAlex Williamson
While the qemu_balloon_inhibit() interface appears rather general purpose, postcopy uses it in a last-caller-wins approach with no guarantee of balanced inhibits and de-inhibits. Wrap postcopy's usage of the inhibitor to give it one vote overall, using the same last-caller-wins approach as previously implemented at the balloon level. Fixes: 01ccbec7bdf6 ("balloon: Allow multiple inhibit users") Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-08-22migration: implement bi-directional RDMA QIOChannelLidong Chen
This patch implements bi-directional RDMA QIOChannel. Because different threads may access RDMAQIOChannel currently, this patch use RCU to protect it. Signed-off-by: Lidong Chen <lidongchen@tencent.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-27postcopy: drop ram_pages parameter from postcopy_ram_incoming_init()David Hildenbrand
Not needed. Don't expose last_ram_page(). Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20180620202736.21399-1-david@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-04migration: discard non-migratable RAMBlocksCédric Le Goater
On the POWER9 processor, the XIVE interrupt controller can control interrupt sources using MMIO to trigger events, to EOI or to turn off the sources. Priority management and interrupt acknowledgment is also controlled by MMIO in the presenter sub-engine. These MMIO regions are exposed to guests in QEMU with a set of 'ram device' memory mappings, similarly to VFIO, and the VMAs are populated dynamically with the appropriate pages using a fault handler. But, these regions are an issue for migration. We need to discard the associated RAMBlocks from the RAM state on the source VM and let the destination VM rebuild the memory mappings on the new host in the post_load() operation just before resuming the system. To achieve this goal, the following introduces a new RAMBlock flag RAM_MIGRATABLE which is updated in the vmstate_register_ram() and vmstate_unregister_ram() routines. This flag is then used by the migration to identify RAMBlocks to discard on the source. Some checks are also performed on the destination to make sure nothing invalid was sent. This change impacts the boston, malta and jazz mips boards for which migration compatibility is broken. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15migration: allow fault thread to pausePeter Xu
Allows the fault thread to stop handling page faults temporarily. When network failure happened (and if we expect a recovery afterwards), we should not allow the fault thread to continue sending things to source, instead, it should halt for a while until the connection is rebuilt. When the dest main thread noticed the failure, it kicks the fault thread to switch to pause state. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180502104740.12123-7-peterx@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-04-25migration: add postcopy total blocktime into query-migrateAlexey Perevalov
Postcopy total blocktime is available on destination side only. But query-migrate was possible only for source. This patch adds ability to call query-migrate on destination. To be able to see postcopy blocktime, need to request postcopy-blocktime capability. The query-migrate command will show following sample result: {"return": "postcopy-vcpu-blocktime": [115, 100], "status": "completed", "postcopy-blocktime": 100 }} postcopy_vcpu_blocktime contains list, where the first item is the first vCPU in QEMU. This patch has a drawback, it combines states of incoming and outgoing migration. Ongoing migration state will overwrite incoming state. Looks like better to separate query-migrate for incoming and outgoing migration or add parameter to indicate type of migration. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Message-Id: <1521742647-25550-7-git-send-email-a.perevalov@samsung.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25migration: calculate vCPU blocktime on dst sideAlexey Perevalov
This patch provides blocktime calculation per vCPU, as a summary and as a overlapped value for all vCPUs. This approach was suggested by Peter Xu, as an improvements of previous approch where QEMU kept tree with faulted page address and cpus bitmask in it. Now QEMU is keeping array with faulted page address as value and vCPU as index. It helps to find proper vCPU at UFFD_COPY time. Also it keeps list for blocktime per vCPU (could be traced with page_fault_addr) Blocktime will not calculated if postcopy_blocktime field of MigrationIncomingState wasn't initialized. Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Message-Id: <1521742647-25550-4-git-send-email-a.perevalov@samsung.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25migration: add postcopy blocktime ctx into MigrationIncomingStateAlexey Perevalov
This patch adds request to kernel space for UFFD_FEATURE_THREAD_ID, in case this feature is provided by kernel. PostcopyBlocktimeContext is encapsulated inside postcopy-ram.c, due to it being a postcopy-only feature. Also it defines PostcopyBlocktimeContext's instance live time. Information from PostcopyBlocktimeContext instance will be provided much after postcopy migration end, instance of PostcopyBlocktimeContext will live till QEMU exit, but part of it (vcpu_addr, page_fault_vcpu_time) used only during calculation, will be released when postcopy ended or failed. To enable postcopy blocktime calculation on destination, need to request proper compatibility (Patch for documentation will be at the tail of the patch set). As an example following command enable that capability, assume QEMU was started with -chardev socket,id=charmonitor,path=/var/lib/migrate-vm-monitor.sock option to control it [root@host]#printf "{\"execute\" : \"qmp_capabilities\"}\r\n \ {\"execute\": \"migrate-set-capabilities\" , \"arguments\": { \"capabilities\": [ { \"capability\": \"postcopy-blocktime\", \"state\": true } ] } }" | nc -U /var/lib/migrate-vm-monitor.sock Or just with HMP (qemu) migrate_set_capability postcopy-blocktime on Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Message-Id: <1521742647-25550-3-git-send-email-a.perevalov@samsung.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>