On 2024/4/4 4:45, Andrew Morton wrote:
On Wed, 3 Apr 2024 16:37:58 +0800 Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
After VMA lock-based page fault handling enabled, if bad access met
under per-vma lock, it will fallback to mmap_lock-based handling,
so it leads to unnessary mmap lock and vma find again. A test from
lmbench shows 34% improve after this changes on arm64,
lat_sig -P 1 prot lat_sig 0.29194 -> 0.19198
Only build test on other archs except arm64.
Thanks. So we now want a bunch of architectures to runtime test this. Do
we have a selftest in place which will adequately do this?
I don't find such selftest, and badaccess would lead to coredump, the
performance should not affect most scene, so no selftest is acceptable.
lmbench is easy to use to measure the performance.