Re: [PATCH v4 05/12] this_cpu_cmpxchg: x86: switch this_cpu_cmpxchg to locked, add _local function

[Peter Zijlstra]

On Sun, Mar 05, 2023 at 10:37:02AM -0300, Marcelo Tosatti wrote:
> Goal is to have vmstat_shepherd to transfer from
> per-CPU counters to global counters remotely. For this,
> an atomic this_cpu_cmpxchg is necessary.
> 
> Following the kernel convention for cmpxchg/cmpxchg_local,
> change x86's this_cpu_cmpxchg_ helpers to be atomic.
> and add this_cpu_cmpxchg_local_ helpers which are not atomic.

Urgh.. much hate for this. this_cpu_*() is local, per definition,
always.