Currently the code contains multiple places where callers expect the errno
to be valid (implied by calling pr_perror to log file IO errors) after
calling open_img_file(), read_fp() and write_fp() helpers. Problem there
is that those helpers can destroy the errno courtesy of themselves
emitting log messages via fprintf.
Furthermore, the callers then sometimes invent the errors to return back
to the caller, or even outside of the plugin.
On top of that there is no benefit to buffered file IO given the plugin
reads and writes in buffer object size chunks, so it it preferrable to
just go direct and avoid any possibility of extra copying to and from libc
temporary buffers.
So lets just convert it all in one swoop to POSIX IO and make sure correct
errnos are always propagated to the caller (including to CRIU core).
Hopefully this removes all instances of incorrect pr_perror log messages.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Reviewed-By: David Francis <David.Francis@amd.com> # v1
---
v2:
* Handle short reads and writes.
* Add O_TRUNC.
v3:
* Handle EINTR and EAGAIN.
* Set errno on len == 0.
* Use %zu for size_t printing.
v4:
* Drop shadowed ret.
* Drop needless casts.
The extra debug build log helper does not seem very useful and some of
them do not even compile. Lets just remove it and replace with the
standard pr_debug. In case of too much noise, we can later re-evaluate
to remove some of the not very useful log messages.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Reviewed-By: David Francis <David.Francis@amd.com>
When the amdgpu plugin is called for restore of a file img,
we don't initially know if it's a kfd or drm file. So we first
try to open a kfd file, and if that fails, we assume it's
a drm file. That failure leads to a lot of error messages like
Error amdgpu_plugin: amdgpu-kfd-141.img: Failed to open for read
For this normal behaviour.
Add an option on open_img_file to suppress this error when
we aren't sure if the file we're trying to open exists.
Signed-off-by: David Francis <David.Francis@amd.com>
amdgpu libraries that use dmabuf fd to share GPU memory between
processes close the dmabuf fds immediately after using them.
However, it is possible that checkpoint of a process catches one
of the dmabuf fds open. In that case, the amdgpu plugin needs
to handle it.
The checkpoint of the dmabuf fd does require the device file
it was exported from to have already been dumped
To identify which device this dmabuf fd was exprted from, attempt
to import it on each device, then record the dmabuf handle
it imports as. This handle can be used to restore it.
Signed-off-by: David Francis <David.Francis@amd.com>
The amdgpu plugin was counting how many files were checkpointed
to determine when it should close the device files.
The number of device files is not consistent; a process may
have multiple copies of the drm device files open.
Instead of doing this counting, add a new callback after all
files are checkpointed, so plugins can clean up their
resources at an appropriate time.
Signed-off-by: David Francis <David.Francis@amd.com>
Buffer objects held by the amdgpu drm driver are checkpointed with
the new BO_INFO and MAPPING_INFO ioctls/ioctl options. Handling
is in amdgpu_plugin_drm.h
Handling of imported buffer objects may require dmabuf fds to be
transferred between processes. These occur over fdstore, with the
handle-fstore id relationships kept in shread memory. There is a
new plugin callback: RESTORE_INIT to create the shared memory.
During checkpoint, track shared buffer objects, so that buffer objects
that are shared across processes can be identified.
During restore, track which buffer objects have been restored. Retry
restore of a drm file if a buffer object is imported and the
original has not been exported yet. Skip buffer objects that have
already been completed or cannot be completed in the current restore.
So drm code can use sdma_copy_bo, that function no longer requires
kfd bo structs
Update the protobuf messages with new amdgpu drm information.
Signed-off-by: David Francis <David.Francis@amd.com>
This patch fixes the following warnings that appear
when building an RPM package:
+ /usr/lib/rpm/redhat/brp-mangle-shebangs
*** WARNING: ./usr/src/debug/criu-4.0-1.fc42.x86_64/plugins/amdgpu/amdgpu_plugin_util.c is executable but has no shebang, removing executable bit
*** WARNING: ./usr/src/debug/criu-4.0-1.fc42.x86_64/plugins/amdgpu/amdgpu_plugin_util.h is executable but has no shebang, removing executable bit
Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>
Add a new compilation unit to host symbols and methods that will be
needed to C&R DRM devices. Refactor code that indicates support for
C&R and checkpoints KFD and DRM devices
Signed-off-by: Ramesh Errabolu <Ramesh.Errabolu@amd.com>
