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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>
2018-03-29migration: fix pfd leakMarc-André Lureau
Fix leak spotted by ASAN: Direct leak of 16 byte(s) in 1 object(s) allocated from: #0 0x7fe1abb80a38 in __interceptor_calloc (/lib64/libasan.so.4+0xdea38) #1 0x7fe1aaf1bf75 in g_malloc0 ../glib/gmem.c:124 #2 0x7fe1aaf1c249 in g_malloc0_n ../glib/gmem.c:355 #3 0x55f4841cfaa9 in postcopy_ram_fault_thread /home/elmarco/src/qemu/migration/postcopy-ram.c:596 #4 0x55f48479447b in qemu_thread_start /home/elmarco/src/qemu/util/qemu-thread-posix.c:504 #5 0x7fe1a043550a in start_thread (/lib64/libpthread.so.0+0x750a) Regression introduced with commit 00fa4fc85b00f1a8a810068d158a7a66e88658eb. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20180321113644.21899-1-marcandre.lureau@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-20postcopy: Allow shared memoryDr. David Alan Gilbert
Now that we have the mechanisms in here, allow shared memory in a postcopy. Note that QEMU can't tell who all the users of shared regions are and thus can't tell whether all the users of the shared regions have appropriate support for postcopy. Those devices that explicitly support shared memory (e.g. vhost-user) must check, but it doesn't stop weirder configurations causing problems. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20vhost+postcopy: Wire up POSTCOPY_END notifyDr. David Alan Gilbert
Wire up a call to VHOST_USER_POSTCOPY_END message to the vhost clients right before we ask the listener thread to shutdown. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20vhost+postcopy: Call wakeupsDr. David Alan Gilbert
Cause the vhost-user client to be woken up whenever: a) We place a page in postcopy mode b) We get a fault and the page has already been received Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20postcopy: postcopy_notify_shared_wakeDr. David Alan Gilbert
Add a hook to allow a client userfaultfd to be 'woken' when a page arrives, and a walker that calls that hook for relevant clients given a RAMBlock and offset. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20postcopy: helper for waking sharedDr. David Alan Gilbert
Provide a helper to send a 'wake' request on a userfaultfd for a shared process. The address in the clients address space is specified together with the RAMBlock it was resolved to. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20postcopy-ram: add a stub for postcopy_request_shared_pageMichael S. Tsirkin
This fixes the build on systems without userfaultfd. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20vhost+postcopy: Helper to send requests to source for shared pagesDr. David Alan Gilbert
Provide a helper to be used by shared waker functions to request shared pages from the source. The last_rb pointer is moved into the incoming state since this helper can update it as well as the main fault thread function. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20postcopy: Allow registering of fd handlerDr. David Alan Gilbert
Allow other userfaultfd's to be registered into the fault thread so that handlers for shared memory can get responses. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20postcopy: Add notifier chainDr. David Alan Gilbert
Add a notifier chain for postcopy with a 'reason' flag and an opportunity for a notifier member to return an error. Call it when enabling postcopy. This will initially used to enable devices to declare they're unable to postcopy and later to notify of devices of stages within postcopy. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20postcopy: use UFFDIO_ZEROPAGE only when availableDr. David Alan Gilbert
Use a flag on the RAMBlock to state whether it has the UFFDIO_ZEROPAGE capability, use it when it's available. This allows the use of postcopy on tmpfs as well as hugepage backed files. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-02-14migration: provide postcopy_fault_thread_notify()Peter Xu
A general helper to notify the fault thread. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180208103132.28452-4-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14migration: reuse mis->userfault_quit_fdPeter Xu
It was only used for quitting the page fault thread before. Let it be something more useful - now we can use it to notify a "wake" for the page fault thread (for any reason), and it only means "quit" if the fault_thread_quit is set. Since we changed what it does, renaming it to userfault_event_fd. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180208103132.28452-3-peterx@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-01-23migration: Revert postcopy-blocktime commit setPeter Maydell
This reverts commits ca6011c migration: add postcopy total blocktime into query-migrate 5f32dc8 migration: add blocktime calculation into migration-test 2f7dae9 migration: postcopy_blocktime documentation 3be98be migration: calculate vCPU blocktime on dst side 01a87f0 migration: add postcopy blocktime ctx into MigrationIncomingState 31bf06a migration: introduce postcopy-blocktime capability as they don't build on ppc32 due to trying to do atomic accesses on types that are larger than the host pointer type. Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-15migration: 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>
2018-01-15migration: 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>
2018-01-15migration: 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>
2017-10-23migration: add bitmap for received pageAlexey Perevalov
This patch adds ability to track down already received pages, it's necessary for calculation vCPU block time in postcopy migration feature, and for recovery after postcopy migration failure. Also it's necessary to solve shared memory issue in postcopy livemigration. Information about received pages will be transferred to the software virtual bridge (e.g. OVS-VSWITCHD), to avoid fallocate (unmap) for already received pages. fallocate syscall is required for remmaped shared memory, due to remmaping itself blocks ioctl(UFFDIO_COPY, ioctl in this case will end with EEXIT error (struct page is exists after remmap). Bitmap is placed into RAMBlock as another postcopy/precopy related bitmaps. Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-10-23migration: introduce qemu_ufd_copy_ioctl helperAlexey Perevalov
Just for placing auxilary operations inside helper, auxilary operations like: track received pages, notify about copying operation in futher patches. Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-10-23migration: postcopy_place_page factoring outAlexey Perevalov
Need to mark copied pages as closer as possible to the place where it tracks down. That will be necessary in futher patch. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-09-22migration: split ufd_version_check onto receive/request features partAlexey Perevalov
This modification is necessary for userfault fd features which are required to be requested from userspace. UFFD_FEATURE_THREAD_ID is a one of such "on demand" feature, which will be introduced in the next patch. QEMU have to use separate userfault file descriptor, due to userfault context has internal state, and after first call of ioctl UFFD_API it changes its state to UFFD_STATE_RUNNING (in case of success), but kernel while handling ioctl UFFD_API expects UFFD_STATE_WAIT_API. So only one ioctl with UFFD_API is possible per ufd. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-09-22migration: fix hardcoded function name in error reportAlexey Perevalov
Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-09-22migration: pass MigrationIncomingState* into migration check functionsAlexey Perevalov
That tiny refactoring is necessary to be able to set UFFD_FEATURE_THREAD_ID while requesting features, and then to create downtime context in case when kernel supports it. Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-06-14migration: Remove unneeded includesJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com>
2017-06-13migration: Move migration.h to migration/Juan Quintela
Nothing uses it outside of migration.h Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com>
2017-06-01migration: Export ram.c functions in its own fileJuan Quintela
All functions are internal except for ram_mig_init(). Create migration/misc.h for this kind of functions. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-06-01migration: Split qemu-file.hJuan Quintela
Split the file into public and internal interfaces. I have to rename the external one because we can't have two include files with the same name in the same directory. Build system gets confused. The only exported functions are the ones that handle basic types. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-06-01migration: shut src return path unconditionallyPeter Xu
We were do the shutting off only for postcopy. Now we do this as long as the source return path is there. Moving the cleanup of from_src_file there too. Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-05-31migration: Create savevm.h for functions exported from savevm.cJuan Quintela
This removes last trace of migration functions from sysemu/sysemu.h. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com>
2017-05-18exec: Create include for target_page_size()Juan Quintela
That is the only function that we need from exec.c, and having to include the whole sysemu.h for this. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> --- /me leans to be less sloppy with copyright notices thanks Dave
2017-05-18migration: Remove qemu-file.h from vmstate.hJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> -- minor rearangements due to the rebase
2017-05-18postcopy: Require RAMBlocks that are whole pagesDr. David Alan Gilbert
It turns out that it's legal to create a VM with RAMBlocks that aren't a multiple of the pagesize in use; e.g. a 1025M main memory using 2M host pages. That breaks postcopy's atomic placement of pages, so disallow it. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-05-17migration: Move postcopy stuff to postcopy-ram.cJuan Quintela
Yes, we don't have a good place to put that stuff. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-05-04migration: Move postcopy-ram.h to migration/Juan Quintela
It is internal to migration, not intended for other users. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-05-04ram: Split dirty bitmap by RAMBlockJuan Quintela
Both the ram bitmap and the unsent bitmap are split by RAMBlock. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com> Reviewed-by: Peter Xu <peterx@redhat.com> -- Fix compilation when DEBUG_POSTCOPY is enabled (thanks Hailiang)
2017-04-21ram: ram_discard_range() don't use the mis parameterJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21ram: Rename qemu_target_page_bits() to qemu_target_page_size()Juan Quintela
It was used as a size in all cases except one. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-03-16postcopy: Check for shared memoryDr. David Alan Gilbert
Postcopy doesn't support migration of RAM shared with another process yet (we've got a bunch of things to understand). Check for the case and don't allow postcopy to be enabled. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-02-28postcopy: Add extra check for COPY functionDr. David Alan Gilbert
As an extra sanity check, make sure the region we're registering can perform UFFDIO_COPY; the COPY will fail later but this gives a cleaner failure. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-17-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28postcopy: Check for userfault+hugepage featureDr. David Alan Gilbert
We need extra Linux kernel support (~4.11) to support userfaults on hugetlbfs; check for them. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-15-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28postcopy: Allow hugepagesDr. David Alan Gilbert
Allow huge pages in postcopy. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-13-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28postcopy: Mask fault addresses to huge page boundaryDr. David Alan Gilbert
Currently the fault address received by userfault is rounded to the host page boundary and a host page is requested from the source. Use the current RAMBlock page size instead of the general host page size so that for RAMBlocks backed by huge pages we request the whole huge page. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-11-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28postcopy: Use temporary for placing zero huge pagesDr. David Alan Gilbert
The kernel can't do UFFDIO_ZEROPAGE for huge pages, so we have to allocate a temporary (always zero) page and use UFFDIO_COPYPAGE on it. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-9-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28postcopy: Plumb pagesize down into place helpersDr. David Alan Gilbert
Now we deal with normal size pages and huge pages we need to tell the place handlers the size we're dealing with and make sure the temporary page is large enough. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-8-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28exec: ram_block_discard_rangeDr. David Alan Gilbert
Create ram_block_discard_range in exec.c to replace postcopy_ram_discard_range and most of ram_discard_range. Those two routines are a bit of a weird combination, and ram_discard_range is about to get more complex for hugepages. It's OS dependent code (so shouldn't be in migration/ram.c) but it needs quite a bit of the innards of RAMBlock so doesn't belong in the os*.c. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-5-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2016-10-13migration/postcopy: Explicitly disallow huge pagesDr. David Alan Gilbert
At the moment postcopy will fail as soon as qemu tries to register userfault on the RAMBlock pages that are backed by hugepages. However, the kernel is going to get userfault support for hugepage at some point, and we've not got the rest of the QEMU code to support it yet, so fail neatly with an error like: Postcopy doesn't support hugetlbfs yet (/objects/mem1) Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-30 20:54:47 +0000