VMware reported the performance regression during memmap_init() invocation.
And they bisected to commit 73a6e474cb376 ("mm: memmap_init: iterate over
memblock regions rather that check each PFN") causing it.
After investigation, it's caused by incorrect memmap init defer handling
in memmap_init_zone() after commit 73a6e474cb376. The current
memmap_init_zone() only handle one memory region of one zone, while
memmap_init() iterates over all its memory regions and pass them one by
one into memmap_init_zone() to handle.
So in this patchset, patch 1/2 fixes the bug observed by VMware. Patch
2/2 clean up the inappropriate name of memmap_init(), memmap_init_zone()
accordingly.
VMware helped do the testing on their VMware ESI platform. This patchset
is based on 5.10.0-rc7+, master branch of Linus's tree.
Baoquan He (2):
mm: memmap defer init dosn't work as expected
mm: rename memmap_init() and memmap_init_zone()
arch/ia64/mm/init.c | 8 ++++----
include/linux/mm.h | 5 +++--
mm/memory_hotplug.c | 2 +-
mm/page_alloc.c | 22 ++++++++++++----------
4 files changed, 20 insertions(+), 17 deletions(-)
--
2.17.2
