[v2,resend,0/3] arm64: mm: Do not defer reserve_crashkernel()

Message

Kefeng Wang March 31, 2022, 7:40 a.m. UTC

Commit 031495635b46 ("arm64: Do not defer reserve_crashkernel() for
platforms with no DMA memory zones"), this lets the kernel benifit
due to BLOCK_MAPPINGS, we could do more if ZONE_DMA and ZONE_DMA32
enabled.

1) Don't defer reserve_crashkernel() if only ZONE_DMA32
2) Don't defer reserve_crashkernel() if ZONE_DMA with dma_force_32bit
   kernel parameter(newly added)

Unixbench benchmark result shows between the block mapping and page mapping.
----------------+------------------+-------------------
        	| block mapping    |   page mapping    
----------------+------------------+-------------------
Process Creation|  5,030.7         |    4,711.8       
(in unixbench)  |                  |                   
----------------+------------------+-------------------

note: RODATA_FULL_DEFAULT_ENABLED is not enabled

v2 resend:
- fix build error reported-by lkp
v2:
- update patch1 according to Vijay and Florian, and RB of Vijay
- add new patch2

Kefeng Wang (3):
  arm64: mm: Do not defer reserve_crashkernel() if only ZONE_DMA32
  arm64: mm: Don't defer reserve_crashkernel() with dma_force_32bit
  arm64: mm: Cleanup useless parameters in zone_sizes_init()

 arch/arm64/include/asm/kexec.h |  1 +
 arch/arm64/mm/init.c           | 59 +++++++++++++++++++++++++---------
 arch/arm64/mm/mmu.c            |  6 ++--
 3 files changed, 46 insertions(+), 20 deletions(-)