25 May
2023
25 May
'23
8:54 a.m.
On Wed, May 24, 2023 at 02:39:50PM -0700, Sean Christopherson wrote:
On Wed, May 24, 2023, Peter Zijlstra wrote:
On Wed, May 24, 2023 at 01:16:03PM -0700, Sean Christopherson wrote:
Of course, the only accesses outside of mmu_lock are reads, so on x86 that "atomic" access is just a READ_ONCE() load, but that's not the case for all architectures.
This is true on *all* archs. atomic_set() and atomic_read() are no more and no less than WRITE_ONCE() / READ_ONCE().
Ah, I take it s390's handcoded assembly routines are just a paranoid equivalents and not truly special? "l" and "st" do sound quite generic...
Yep, compiler *should* generate the same with READ_ONCE/WRITE_ONCE.