Hi Eric, Good idea to do it also for wfstack.
A few comments below, ----- Original Message ----- > From: "Eric Wong" <[email protected]> > To: "Mathieu Desnoyers" <[email protected]> > Cc: [email protected], "Paul E. McKenney" > <[email protected]>, "Lai Jiangshan" > <[email protected]> > Sent: Monday, August 18, 2014 1:02:54 AM > Subject: [PATCH urcu] wfstack: implement mutex-free wfstack with transparent > union > > This saves space for users who use alternative synchronization > mechanisms. > > Signed-off-by: Eric Wong <[email protected]> > Cc: Paul E. McKenney <[email protected]> > Cc: Lai Jiangshan <[email protected]> > Cc: Mathieu Desnoyers <[email protected]> > --- > urcu/static/wfstack.h | 18 +++++++++++++++--- > urcu/wfstack.h | 23 +++++++++++++++++++++-- > wfstack.c | 9 +++++++-- > 3 files changed, 43 insertions(+), 7 deletions(-) > > diff --git a/urcu/static/wfstack.h b/urcu/static/wfstack.h > index db0d5b8..eb12f37 100644 > --- a/urcu/static/wfstack.h > +++ b/urcu/static/wfstack.h > @@ -77,6 +77,14 @@ void _cds_wfs_node_init(struct cds_wfs_node *node) > } > > /* > + * __cds_wfs_init: initialize wait-free stack. > + */ > +static inline void ___cds_wfs_init(struct __cds_wfs_stack *s) > +{ > + s->head = CDS_WFS_END; > +} > + > +/* > * cds_wfs_init: initialize wait-free stack. > */ > static inline > @@ -99,8 +107,10 @@ static inline bool ___cds_wfs_end(void *node) > * > * No memory barrier is issued. No mutual exclusion is required. > */ > -static inline bool _cds_wfs_empty(struct cds_wfs_stack *s) > +static inline bool _cds_wfs_empty(cds_wfs_stack_ptr_t u_stack) > { > + struct __cds_wfs_stack *s = u_stack._s; > + > return ___cds_wfs_end(CMM_LOAD_SHARED(s->head)); > } > > @@ -114,8 +124,9 @@ static inline bool _cds_wfs_empty(struct cds_wfs_stack > *s) > * Returns non-zero otherwise. > */ > static inline > -int _cds_wfs_push(struct cds_wfs_stack *s, struct cds_wfs_node *node) > +int _cds_wfs_push(cds_wfs_stack_ptr_t u_stack, struct cds_wfs_node *node) > { > + struct __cds_wfs_stack *s = u_stack._s; > struct cds_wfs_head *old_head, *new_head; > > assert(node->next == NULL); > @@ -269,8 +280,9 @@ ___cds_wfs_pop_nonblocking(struct cds_wfs_stack *s) > */ > static inline > struct cds_wfs_head * > -___cds_wfs_pop_all(struct cds_wfs_stack *s) > +___cds_wfs_pop_all(cds_wfs_stack_ptr_t u_stack) > { > + struct __cds_wfs_stack *s = u_stack._s; > struct cds_wfs_head *head; > > /* > diff --git a/urcu/wfstack.h b/urcu/wfstack.h > index fc0b44b..8d6f22c 100644 > --- a/urcu/wfstack.h > +++ b/urcu/wfstack.h > @@ -83,11 +83,25 @@ struct cds_wfs_head { > struct cds_wfs_node node; > }; > > +struct __cds_wfs_stack { > + struct cds_wfs_head *head; > +}; > + > struct cds_wfs_stack { > struct cds_wfs_head *head; > pthread_mutex_t lock; > }; > > +/* > + * The transparent union allows calling functions that work on both > + * struct cds_wfcq_head and struct __cds_wfcq_head on any of those two should be: struct cds_wfs_stack and struct __cds_wfs_stack Other than that, looks good! Can you send an updated version ? Thanks, Mathieu > + * types. > + */ > +typedef union __attribute__((__transparent_union__)) { > + struct __cds_wfs_stack *_s; > + struct cds_wfs_stack *s; > +} cds_wfs_stack_ptr_t; > + > #ifdef _LGPL_SOURCE > > #include <urcu/static/wfstack.h> > @@ -136,11 +150,16 @@ extern void cds_wfs_node_init(struct cds_wfs_node > *node); > extern void cds_wfs_init(struct cds_wfs_stack *s); > > /* > + * __cds_wfs_init: initialize wait-free stack. > + */ > +extern void __cds_wfs_init(struct __cds_wfs_stack *s); > + > +/* > * cds_wfs_empty: return whether wait-free stack is empty. > * > * No memory barrier is issued. No mutual exclusion is required. > */ > -extern bool cds_wfs_empty(struct cds_wfs_stack *s); > +extern bool cds_wfs_empty(cds_wfs_stack_ptr_t u_stack); > > /* > * cds_wfs_push: push a node into the stack. > @@ -151,7 +170,7 @@ extern bool cds_wfs_empty(struct cds_wfs_stack *s); > * Returns 0 if the stack was empty prior to adding the node. > * Returns non-zero otherwise. > */ > -extern int cds_wfs_push(struct cds_wfs_stack *s, struct cds_wfs_node *node); > +extern int cds_wfs_push(cds_wfs_stack_ptr_t u_stack, struct cds_wfs_node > *node); > > /* > * cds_wfs_pop_blocking: pop a node from the stack. > diff --git a/wfstack.c b/wfstack.c > index c8bd7e6..fec9e47 100644 > --- a/wfstack.c > +++ b/wfstack.c > @@ -38,6 +38,11 @@ void cds_wfs_init(struct cds_wfs_stack *s) > _cds_wfs_init(s); > } > > +void __cds_wfs_init(struct __cds_wfs_stack *s) > +{ > + ___cds_wfs_init(s); > +} > + > bool cds_wfs_empty(struct cds_wfs_stack *s) > { > return _cds_wfs_empty(s); > @@ -112,7 +117,7 @@ struct cds_wfs_node * > return ___cds_wfs_pop_with_state_nonblocking(s, state); > } > > -struct cds_wfs_head *__cds_wfs_pop_all(struct cds_wfs_stack *s) > +struct cds_wfs_head *__cds_wfs_pop_all(cds_wfs_stack_ptr_t u_stack) > { > - return ___cds_wfs_pop_all(s); > + return ___cds_wfs_pop_all(u_stack); > } > -- > EW > > -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
