----- Original Message ----- > From: "Richard Henderson" <[email protected]> > To: "Paolo Bonzini" <[email protected]>, [email protected] > Cc: "serge fdrv" <[email protected]>, [email protected], "alex bennee" > <[email protected]>, "sergey fedorov" > <[email protected]> > Sent: Friday, September 23, 2016 8:06:09 PM > Subject: Re: [Qemu-devel] [PATCH 15/16] tcg: Make tb_flush() thread safe > > On 09/23/2016 12:31 AM, Paolo Bonzini wrote: > > + unsigned tb_flush_req = (unsigned) (uintptr_t) data; > > Extra cast? > > > - tcg_ctx.tb_ctx.tb_flush_count++; > > + atomic_inc(&tcg_ctx.tb_ctx.tb_flush_count); > > Since this is the only place this value is incremented, and we're under a > lock, > it should be cheaper to use > > atomic_mb_set(&tcg_ctx.tb_ctx.tb_flush_count, tb_flush_req + 1);
atomic_set will do even. Though it's not really a fast path, which is why I went for atomic_inc. > > + uintptr_t tb_flush_req = (uintptr_t) > > + atomic_read(&tcg_ctx.tb_ctx.tb_flush_count); > > Extra cast? Yeah. Paolo > That said, it's correct as-is so, > > Reviewed-by: Richard Henderson <[email protected]> > > > r~ >
