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2013-03-11migration: run setup callbacks out of big lockPaolo Bonzini
Only the migration_bitmap_sync() call needs the iothread lock. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: run pending/iterate callbacks out of big lockPaolo Bonzini
This makes it possible to do blocking writes directly to the socket, with no buffer in the middle. For RAM, only the migration_bitmap_sync() call needs the iothread lock. For block migration, it is needed by the block layer (including bdrv_drain_all and dirty bitmap access), but because some code is shared between iterate and complete, all of mig_save_device_dirty is run with the lock taken. In the savevm case, the iterate callback runs within the big lock. This is annoying because it complicates the rules. Luckily we do not need to do anything about it: the RAM iterate callback does not need the iothread lock, and block migration never runs during savevm. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: add lockPaolo Bonzini
Some state is shared between the block migration code and its AIO callbacks. Once block migration will run outside the iothread, the block migration code and the AIO callbacks will be able to run concurrently. Protect the critical sections with a separate lock. Do the same for completed_sectors, which can be used from the monitor. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: document usage of state across threadsPaolo Bonzini
Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: small preparatory changes for lockingPaolo Bonzini
Some small changes that will simplify the positioning of lock/unlock primitives. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: remove variables that are never readPaolo Bonzini
Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: remove useless calls to blk_mig_cleanupPaolo Bonzini
Now that the cancel callback is called consistently for all errors, we can avoid doing its work in the other callbacks. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-02-12block-migration: fix pending() and iterate() return valuesStefan Hajnoczi
The return value of .save_live_pending() is the number of bytes remaining. This is just an estimate because we do not know how many blocks will be dirtied by the running guest. Currently our return value for .save_live_pending() is wrong because it includes dirty blocks but not in-flight bdrv_aio_readv() requests or unsent blocks. Crucially, it also doesn't include the bulk phase where the entire device is transferred - therefore we risk completing block migration before all blocks have been transferred! The return value of .save_live_iterate() is the number of bytes transferred this iteration. Currently we return whether there are bytes remaining, which is incorrect. Move the bytes remaining calculation into .save_live_pending() and really return the number of bytes transferred this iteration in .save_live_iterate(). Also fix the %ld format specifier which was used for a uint64_t argument. PRIu64 must be use to avoid warnings on 32-bit hosts. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-id: 1360661835-28663-3-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11block-migration: fix block_save_iterate() return valueStefan Hajnoczi
The .save_live_iterate() function returns 0 to continue iterating or 1 to stop iterating. Since 16310a3cca7320edb9341c976f7819de0a8c27e0 it only ever returns 0, leading to an infinite loop. Return 1 if we have finished sending dirty blocks. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1360534366-26723-4-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11block-migration: fix blk_mig_save_dirty_block() return value checkingStefan Hajnoczi
Commit 43be3a25c931a7f61a76fbfc9d35584cbfc5fb58 changed the blk_mig_save_dirty_block() return code handling. The function's doc comment says: /* return value: * 0: too much data for max_downtime * 1: few enough data for max_downtime */ Because of the 1 return value, callers must check for ret < 0 instead of just: if (ret) { ... } We do not want to bail when 1 is returned, only on error. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1360534366-26723-3-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11block-migration: improve "Unknown flags" error messageStefan Hajnoczi
Show the actual flags value and include "block migration" in the error message so it's clear where the error is coming from. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1360534366-26723-2-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-01-25block: allow customizing the granularity of the dirty bitmapPaolo Bonzini
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-25block: return count of dirty sectors, not chunksPaolo Bonzini
Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-12-20savevm: New save live migration method: pendingJuan Quintela
Code just now does (simplified for clarity) if (qemu_savevm_state_iterate(s->file) == 1) { vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); qemu_savevm_state_complete(s->file); } Problem here is that qemu_savevm_state_iterate() returns 1 when it knows that remaining memory to sent takes less than max downtime. But this means that we could end spending 2x max_downtime, one downtime in qemu_savevm_iterate, and the other in qemu_savevm_state_complete. Changed code to: pending_size = qemu_savevm_state_pending(s->file, max_size); DPRINTF("pending size %lu max %lu\n", pending_size, max_size); if (pending_size >= max_size) { ret = qemu_savevm_state_iterate(s->file); } else { vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); qemu_savevm_state_complete(s->file); } So what we do is: at current network speed, we calculate the maximum number of bytes we can sent: max_size. Then we ask every save_live section how much they have pending. If they are less than max_size, we move to complete phase, otherwise we do an iterate one. This makes things much simpler, because now individual sections don't have to caluclate the bandwidth (it was implossible to do right from there). Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19softmmu: move include files to include/sysemu/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19misc: move include files to include/qemu/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19migration: move include files to include/migration/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19block: move include files to include/block/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-17block-migration: handle errors with the return codes correctlyJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-17block-migration: Switch meaning of return valueJuan Quintela
Make consistent the result of blk_mig_save_dirty_block() and mig_save_device_dirty() Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-17block-migration: make flush_blks() return errorsJuan Quintela
This means we don't need to pass through qemu_file to get the errors. Adjust all callers. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-09-28block-migration: Flush requests in blk_mig_cleanupKevin Wolf
When cancelling block migration, all in-flight requests of the block migration must be completed before the data can be freed. This was visible as failing assertions and segfaults. Reported-by: Peter Lieven <pl@dlhnet.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-07-20savevm: split save_live into stage2 and stage3Juan Quintela
We split it into 2 functions, foo_live_iterate, and foo_live_complete. At this point, we only remove the bits that are for the other stage, functionally this is equivalent to previous code. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: split save_live_setup from save_live_stateJuan Quintela
This patch splits stage 1 to its own function for both save_live users, ram and block. It is just a copy of the function, removing the parts of the other stages. Optimizations would came later. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: introduce is_active methodJuan Quintela
Enable the creation of a method to tell migration if that section is active and should be migrate. We use it for blk-migration, that is normally not active. We don't create the method for RAM, as setups without RAM are very strange O:-) Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: Refactor cancel operation in its own operationJuan Quintela
Intead of abusing stage with value -1. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: Live migration handlers register the struct directlyJuan Quintela
Notice that the live migration users never unregister, so no problem about freeing the ops structure. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-06-29Add MigrationParams structureIsaku Yamahata
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
2012-03-15Purge migration of (almost) everything to do with monitorsLuiz Capitulino
The Monitor object is passed back and forth within the migration/savevm code so that it can print errors and progress to the user. However, that approach assumes a HMP monitor, being completely invalid in QMP. This commit drops almost every single usage of the Monitor object, all monitor_printf() calls have been converted into DPRINTF() ones. There are a few remaining Monitor objects, those are going to be dropped by the next commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-01-13prepare for future GPLv2+ relicensingPaolo Bonzini
All files under GPLv2 will get GPLv2+ changes starting tomorrow. event_notifier.c and exec-obsolete.h were only ever touched by Red Hat employees and can be relicensed now. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-12-15block: bdrv_aio_* do not return NULLPaolo Bonzini
Initially done with the following semantic patch: @ rule1 @ expression E; statement S; @@ E = ( bdrv_aio_readv | bdrv_aio_writev | bdrv_aio_flush | bdrv_aio_discard | bdrv_aio_ioctl ) (...); ( - if (E == NULL) { ... } | - if (E) { <... S ...> } ) which however missed the occurrence in block/blkverify.c (as it should have done), and left behind some unused variables. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-12-05block: convert qemu_aio_flush() calls to bdrv_drain_all()Stefan Hajnoczi
Many places in QEMU call qemu_aio_flush() to complete all pending asynchronous I/O. Most of these places actually want to drain all block requests but there is no block layer API to do so. This patch introduces the bdrv_drain_all() API to wait for requests across all BlockDriverStates to complete. As a bonus we perform checks after qemu_aio_wait() to ensure that requests really have finished. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-17Fix some spelling bugs in documentation and commentsStefan Weil
These errors were detected by codespell: remaing -> remaining soley -> solely virutal -> virtual seperate -> separate libcacard.txt still needs some more patches. Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-10-20migration: make *save_live return errorsJuan Quintela
Make *save_live() return negative values when there is one error, and updates all callers to check for the error. Signed-off-by: Juan Quintela <quintela@redhat.com>
2011-10-20migration: use qemu_file_get_error() return value when possibleJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com>
2011-10-20migration: rename qemu_file_has_error to qemu_file_get_errorJuan Quintela
Now the function returned errno, so it is better the new name. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
2011-10-20migration: change has_error to contain errno valuesJuan Quintela
We normally already have an errno value. When not, abuse EIO. Signed-off-by: Juan Quintela <quintela@redhat.com>
2011-08-20Use glib memory allocation and free functionsAnthony Liguori
qemu_malloc/qemu_free no longer exist after this commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-06-24Strip trailing '\n' from error_report()'s first argumentMarkus Armbruster
error_report() prepends location, and appends a newline. The message constructed from the arguments should not contain a newline. Fix the obvious offenders. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-04-27Improve accuracy of block migration bandwidth calculationAvishay Traeger
block_mig_state.total_time is currently the sum of the read request latencies. This is not very accurate because block migration uses aio and so several requests can be submitted at once. Bandwidth should be computed with wall-clock time, not by adding the latencies. In this case, "total_time" has a higher value than it should, and so the computed bandwidth is lower than it is in reality. This means that migration can take longer than it needs to. However, we don't want to use pure wall-clock time here. We are computing bandwidth in the asynchronous phase, where the migration repeatedly wakes up and sends some aio requests. The computed bandwidth will be used for synchronous transfer. Signed-off-by: Avishay Traeger <avishay@il.ibm.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-07Fix integer overflow in block migration bandwidth calculationAvishay Traeger
block_mig_state.reads is an int, and multiplying by BLOCK_SIZE yielded a negative number, resulting in a negative bandwidth (running on a 32-bit machine). Change order to avoid. Signed-off-by: Avishay Traeger <avishay@il.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-07block: enable in_use flagMarcelo Tosatti
Set block device in use during block migration, disallow drive_del and bdrv_truncate for in use devices. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-07block-migration: add reference to target DriveInfoMarcelo Tosatti
So that ejection of attached device by guest does not free data in use by block migration instance. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> CC: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-07block-migration: actually disable dirty tracking on cleanupMarcelo Tosatti
Call to set_dirty_tracking() is misplaced. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24Fix block migration when the device size is not a multiple of 1 MBPierre Riteau
b02bea3a85cc939f09aa674a3f1e4f36d418c007 added a check on the return value of bdrv_write and aborts migration when it fails. However, if the size of the block device to migrate is not a multiple of BLOCK_SIZE (currently 1 MB), the last bdrv_write will fail with -EIO. Fixed by calling bdrv_write with the correct size of the last block. Signed-off-by: Pierre Riteau <Pierre.Riteau@irisa.fr> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24Avoid divide by zero when there is no block device to migratePierre Riteau
When block migration is requested and no read-write block device is present, a divide by zero exception is triggered because total_sector_sum equals zero. Signed-off-by: Pierre Riteau <Pierre.Riteau@irisa.fr> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-11-24block migration: do not submit multiple AIOs for same sector (v2)Marcelo Tosatti
An old version of this patch was applied to master, so this contains the differences between v1 and v2. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-11-21block migration: do not submit multiple AIOs for same sectorMarcelo Tosatti
Block migration can submit multiple AIO reads for the same sector/chunk, but completion of such reads can happen out of order: migration guest - get_dirty(N) - aio_read(N) - clear_dirty(N) write(N) set_dirty(N) - get_dirty(N) - aio_read(N) If the first aio_read completes after the second, stale data will be migrated to the destination. Fix by not allowing multiple AIOs inflight for the same sector. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-08-03block migration: replace tabs by spaces.Yoshiaki Tamura
Signed-off-by: Yoshiaki Tamura <tamura.yoshiaki@lab.ntt.co.jp> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-26block migration: propagate return value when bdrv_write() returns < 0Yoshiaki Tamura
Currently block_load() doesn't check return value of bdrv_write(), and even the destination weren't prepared to execute block migration, it proceeds and guest boots on the target. This patch fix this issue. Signed-off-by: Yoshiaki Tamura <tamura.yoshiaki@lab.ntt.co.jp> Signed-off-by: Kevin Wolf <kwolf@redhat.com>