mbox series

[v4,0/1] Initialize backend memory objects in parallel

Message ID 20240131165327.3154970-1-mark.kanda@oracle.com (mailing list archive)
Headers show
Series Initialize backend memory objects in parallel | expand

Message

Mark Kanda Jan. 31, 2024, 4:53 p.m. UTC 
v4:
- remove unneeded async check from host_memory_backend_set_prealloc()
- rename qemu_finish_async_mem_prealloc -> qemu_finish_async_prealloc_mem
- use new phase PHASE_LATE_BACKENDS_CREATED for async

v3:
- squash into a single patch
- use global context list for async handling only (MT capability)
- add BQL asserts to guard against concurrent async prealloc requests
- clean up qemu_finish_async_mem_prealloc() error handling

Includes David's suggested restructuring [1] (with David's SoB).

[1] https://lore.kernel.org/qemu-devel/c15161eb-f52c-4a82-8b4b-0ba03842188c@redhat.com/

v2:
- require MADV_POPULATE_WRITE (simplify the implementation)
- require prealloc context threads to ensure optimal thread placement
- use machine phase 'initialized' to determine when to allow parallel init

QEMU initializes preallocated backend memory when parsing the corresponding
objects from the command line. In certain scenarios, such as memory being
preallocated across multiple numa nodes, this approach is not optimal due to
the unnecessary serialization.

This series addresses this issue by initializing the backend memory objects in
parallel.

Mark Kanda (1):
  oslib-posix: initialize backend memory objects in parallel

 backends/hostmem.c     |   7 ++-
 hw/virtio/virtio-mem.c |   4 +-
 include/hw/qdev-core.h |   5 ++
 include/qemu/osdep.h   |  18 +++++-
 system/vl.c            |   9 +++
 util/oslib-posix.c     | 131 +++++++++++++++++++++++++++++++----------
 util/oslib-win32.c     |   8 ++-
 7 files changed, 145 insertions(+), 37 deletions(-)