On 2016年06月03日 19:37, Peter Zijlstra wrote:
On Fri, Jun 03, 2016 at 05:48:50PM +0800, Pan Xinhui wrote:
queued_spin_lock_slowpath should not worry about interrupt change
node->count by accident because ->count is inc and dec when we
enter/leave queued_spin_lock_slowpath.
So this_cpu_dec() does some no point things here, lets use this_cpu_ptr
for a small optimization.
Uhm, have you actually looked at what that does on x86?
yep, just one instruction inc/dec.
well, with my patch, there are two instructions.
