Commit Graph

10 Commits

Author SHA1 Message Date
Fabiano Rosas
61dec06082 migration/multifd: Don't fsync when closing QIOChannelFile
Commit bc38feddeb ("io: fsync before closing a file channel") added a
fsync/fdatasync at the closing point of the QIOChannelFile to ensure
integrity of the migration stream in case of QEMU crash.

The decision to do the sync at qio_channel_close() was not the best
since that function runs in the main thread and the fsync can cause
QEMU to hang for several minutes, depending on the migration size and
disk speed.

To fix the hang, remove the fsync from qio_channel_file_close().

At this moment, the migration code is the only user of the fsync and
we're taking the tradeoff of not having a sync at all, leaving the
responsibility to the upper layers.

Fixes: bc38feddeb ("io: fsync before closing a file channel")
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240305195629.9922-1-farosas@suse.de
Link: https://lore.kernel.org/r/20240305174332.2553-1-farosas@suse.de
[peterx: add more comment to the qio_channel_close()]
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-03-11 14:41:40 -04:00
Fabiano Rosas
c35462f19b docs/devel/migration.rst: Document the file transport
When adding the support for file migration with the file: transport,
we missed adding documentation for it.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240220224138.24759-2-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-02-28 11:31:28 +08:00
Bernhard Beschow
f165cdf102 exec/ioport: Add portio_list_set_enabled()
Some SuperI/O devices such as the VIA south bridges or the PC87312 controller
allow to enable or disable their SuperI/O functions. Add a convenience function
for implementing this in the VIA south bridges.

The naming of the functions is inspired by its memory_region_set_enabled()
pendant.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20240114123911.4877-7-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2024-02-14 06:09:32 -05:00
Bernhard Beschow
ad2b652341 exec/ioport: Add portio_list_set_address()
Some SuperI/O devices such as the VIA south bridges or the PC87312 controller
are able to relocate their SuperI/O functions. Add a convenience function for
implementing this in the VIA south bridges.

This convenience function relies on previous simplifications in exec/ioport
which avoids some duplicate synchronization of I/O port base addresses. The
naming of the function is inspired by its memory_region_set_address() pendant.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20240114123911.4877-6-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2024-02-14 06:09:32 -05:00
Peter Xu
4c6f8a79ae docs/migration: Split "dirty limit"
Split that into a separate file, put under "features".

Cc: Yong Huang <yong.huang@smartx.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-8-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-16 11:16:10 +08:00
Peter Xu
bfb4c7cd99 docs/migration: Split "Postcopy"
Split postcopy into a separate file.  Introduce a head page "features.rst"
to keep all the features on top of migration framework.

Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-7-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-16 11:16:10 +08:00
Peter Xu
774ad6b53b docs/migration: Split "Debugging" and "Firmware"
Move the two sections into a separate file called "best-practices.rst".
Add the entry into index.

Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-6-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-16 11:16:10 +08:00
Peter Xu
6cc6a7b98b docs/migration: Split "Backwards compatibility" separately
Split the section from main.rst into a separate file.  Reference it in the
index.rst.

Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-5-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-16 11:16:10 +08:00
Peter Xu
f6bbac985e docs/migration: Create index page
Create an index page for migration module.  Move VFIO migration there too.
A trivial touch-up on the title to use lower case there.

Since then we'll have "migration" as the top title, make the main doc file
renamed to "migration framework".

Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-16 11:16:10 +08:00
Peter Xu
8cb2f8b172 docs/migration: Create migration/ directory
Migration documentation is growing into a single file too large.  Create a
sub-directory for it for a split.

We also already have separate vfio/virtio documentations, move it all over
into the directory.

Note that the virtio one is still not yet converted to rST.  That is a job
for later.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-16 11:16:10 +08:00