lkml.org 
[lkml]   [2023]   [Jul]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH v2 0/4] riscv: tlb flush improvements
Date
This series optimizes the tlb flushes on riscv which used to simply
flush the whole tlb whatever the size of the range to flush or the size
of the stride.

Patch 3 introduces a threshold that is microarchitecture specific and
will very likely be modified by vendors, not sure though which mechanism
we'll use to do that (dt? alternatives? vendor initialization code?).

Next steps would be to implement:
- svinval extension as Mayuresh did here [1]
- BATCHED_UNMAP_TLB_FLUSH (I'll wait for arm64 patchset to land)
- MMU_GATHER_RCU_TABLE_FREE
- MMU_GATHER_MERGE_VMAS

Any other idea welcome.

[1] https://lore.kernel.org/linux-riscv/20230623123849.1425805-1-mchitale@ventanamicro.com/

Changes in v2:
- Make static tlb_flush_all_threshold, we'll figure out later how to
override this value on a vendor basis, as suggested by Conor and Palmer
- Fix nommu build, as reported by Conor

Alexandre Ghiti (4):
riscv: Improve flush_tlb()
riscv: Improve flush_tlb_range() for hugetlb pages
riscv: Make __flush_tlb_range() loop over pte instead of flushing the
whole tlb
riscv: Improve flush_tlb_kernel_range()

arch/riscv/include/asm/tlb.h | 8 ++-
arch/riscv/include/asm/tlbflush.h | 12 ++--
arch/riscv/mm/tlbflush.c | 93 +++++++++++++++++++++++++++----
3 files changed, 96 insertions(+), 17 deletions(-)

--
2.39.2

\
 
 \ /
  Last update: 2023-07-27 20:56    [W:0.081 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site