diff options
Diffstat (limited to 'include/linux/rcupdate.h')
| -rw-r--r-- | include/linux/rcupdate.h | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 1a32036c918c..1e728d544fc1 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -169,13 +169,17 @@ void synchronize_rcu_tasks(void); # endif # ifdef CONFIG_TASKS_TRACE_RCU -# define rcu_tasks_trace_qs(t) \ - do { \ - if (!likely(READ_ONCE((t)->trc_reader_checked)) && \ - !unlikely(READ_ONCE((t)->trc_reader_nesting))) { \ - smp_store_release(&(t)->trc_reader_checked, true); \ - smp_mb(); /* Readers partitioned by store. */ \ - } \ +// Bits for ->trc_reader_special.b.need_qs field. +#define TRC_NEED_QS 0x1 // Task needs a quiescent state. +#define TRC_NEED_QS_CHECKED 0x2 // Task has been checked for needing quiescent state. + +u8 rcu_trc_cmpxchg_need_qs(struct task_struct *t, u8 old, u8 new); + +# define rcu_tasks_trace_qs(t) \ + do { \ + if (likely(!READ_ONCE((t)->trc_reader_special.b.need_qs)) && \ + likely(!READ_ONCE((t)->trc_reader_nesting))) \ + rcu_trc_cmpxchg_need_qs((t), 0, TRC_NEED_QS_CHECKED); \ } while (0) # else # define rcu_tasks_trace_qs(t) do { } while (0) |