All references to pages are being removed from the multifd worker
threads in order to allow multifd to deal with different payload
types.
multifd_send_zero_page_detect() is called by all multifd migration
paths that deal with pages and is the last spot where zero pages and
normal page amounts are adjusted. Move the pages accounting into that
function.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
We want multifd to be able to handle more types of data than just ram
pages. To start decoupling multifd from pages, replace p->pages
(MultiFDPages_t) with the new type MultiFDSendData that hides the
client payload inside an union.
The general idea here is to isolate functions that *need* to handle
MultiFDPages_t and move them in the future to multifd-ram.c, while
multifd.c will stay with only the core functions that handle
MultiFDSendData/MultiFDRecvData.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The MultiFD*Params structures are for per-channel data. Constant
values should not be there because that needlessly wastes cycles and
storage. The page_size and page_count fall into this category so move
them inline in multifd.h.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Implemented recvbitmap tracking of received pages in multifd.
If the zero page appears for the first time in the recvbitmap, this
page is not checked and set.
If the zero page has already appeared in the recvbitmap, there is no
need to check the data but directly set the data to 0, because it is
unlikely that the zero page will be migrated multiple times.
Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240401154110.2028453-2-yuan1.liu@intel.com
[peterx: touch up the comment, as the bitmap is used outside postcopy now]
Signed-off-by: Peter Xu <peterx@redhat.com>
1. Add zero_pages field in MultiFDPacket_t.
2. Implements the zero page detection and handling on the multifd
threads for non-compression, zlib and zstd compression backends.
3. Added a new value 'multifd' in ZeroPageDetection enumeration.
4. Adds zero page counters and updates multifd send/receive tracing
format to track the newly added counters.
Signed-off-by: Hao Xiang <hao.xiang@bytedance.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240311180015.3359271-5-hao.xiang@linux.dev
Signed-off-by: Peter Xu <peterx@redhat.com>
