On Tue, Jan 21, 2020 at 09:29:19PM +0100, Peter Zijlstra wrote: > > various notes and changes in the below. > > --- > > Index: linux-2.6/kernel/locking/qspinlock.c > =================================================================== > --- linux-2.6.orig/kernel/locking/qspinlock.c > +++ linux-2.6/kernel/locking/qspinlock.c > @@ -598,10 +598,10 @@ EXPORT_SYMBOL(queued_spin_lock_slowpath) > #define _GEN_CNA_LOCK_SLOWPATH > > #undef pv_wait_head_or_lock > -#define pv_wait_head_or_lock cna_pre_scan > +#define pv_wait_head_or_lock cna_wait_head_or_lock > > #undef try_clear_tail > -#define try_clear_tail cna_try_change_tail > +#define try_clear_tail cna_try_clear_tail > > #undef mcs_pass_lock > #define mcs_pass_lock cna_pass_lock > Index: linux-2.6/kernel/locking/qspinlock_cna.h > =================================================================== > --- linux-2.6.orig/kernel/locking/qspinlock_cna.h > +++ linux-2.6/kernel/locking/qspinlock_cna.h > @@ -8,37 +8,37 @@ > /* > * Implement a NUMA-aware version of MCS (aka CNA, or compact NUMA-aware lock). > * > - * In CNA, spinning threads are organized in two queues, a main queue for > + * In CNA, spinning threads are organized in two queues, a primary queue for > * threads running on the same NUMA node as the current lock holder, and a > - * secondary queue for threads running on other nodes. Schematically, it > - * looks like this: > + * secondary queue for threads running on other nodes. Schematically, it looks > + * like this: > * > * cna_node > - * +----------+ +--------+ +--------+ > - * |mcs:next | -> |mcs:next| -> ... |mcs:next| -> NULL [Main queue] > - * |mcs:locked| -+ +--------+ +--------+ > + * +----------+ +--------+ +--------+ > + * |mcs:next | --> |mcs:next| --> ... |mcs:next| --> NULL [Primary queue] > + * |mcs:locked| -. +--------+ +--------+ > * +----------+ | > - * +----------------------+ > - * \/ > + * `----------------------. > + * v > * +--------+ +--------+ > - * |mcs:next| -> ... |mcs:next| [Secondary queue] > + * |mcs:next| --> ... |mcs:next| [Secondary queue] > * +--------+ +--------+ > * ^ | > - * +--------------------+ > + * `--------------------' > * > - * N.B. locked = 1 if secondary queue is absent. Othewrise, it contains the > + * N.B. locked := 1 if secondary queue is absent. Othewrise, it contains the If we're redoing the comment, please can you s/Othewrise/Otherwise/ at the same time? It catches me every time I read it! Will
