Re: [RFC PATCH 1/1] smp: Change function signatures to use call_single_data_t

[Peter Zijlstra]

On Thu, Aug 31, 2023 at 03:31:28AM -0300, Leonardo Bras wrote:
> call_single_data_t is a size-aligned typedef of struct __call_single_data.
> 
> This alignment is desirable in order to have smp_call_function*() avoid
> bouncing an extra cacheline in case of an unaligned csd, given this
> would hurt performance.
> 
> Since the removal of struct request->csd in commit 660e802c76c8
> ("blk-mq: use percpu csd to remote complete instead of per-rq csd") there
> are no current users of smp_call_function*() with unaligned csd.
> 
> Change every 'struct __call_single_data' function parameter to
> 'call_single_data_t', so we have warnings if any new code tries to
> introduce an smp_call_function*() call with unaligned csd.
> 
> Signed-off-by: Leonardo Bras <leobras@xxxxxxxxxx>

Fair enough, I'll go queue it somewhere.