Re: [PATCH] fs/dcache: optimize start_dir_add()

2020-10-26 Thread Dave Chinner
On Thu, Oct 22, 2020 at 02:16:50PM -0700, Davidlohr Bueso wrote: > Considering both end_dir_add() and d_alloc_parallel(), the > dir->i_dir_seq wants acquire/release semantics, therefore > micro-optimize for ll/sc archs and use finer grained barriers > to provide (load)-ACQUIRE ordering (L->S +

[PATCH] fs/dcache: optimize start_dir_add()

2020-10-22 Thread Davidlohr Bueso
Considering both end_dir_add() and d_alloc_parallel(), the dir->i_dir_seq wants acquire/release semantics, therefore micro-optimize for ll/sc archs and use finer grained barriers to provide (load)-ACQUIRE ordering (L->S + L->L). This comes at no additional cost for most of x86, as sane tso models