* [PATCH] srcu: Add comments for srcu_size_state @ 2022-12-23 13:02 Pingfan Liu 2023-01-04 20:43 ` Paul E. McKenney 0 siblings, 1 reply; 3+ messages in thread From: Pingfan Liu @ 2022-12-23 13:02 UTC (permalink / raw) To: rcu Cc: Pingfan Liu, Lai Jiangshan, Paul E. McKenney, Frederic Weisbecker, Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Zhang, Qiang1 Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Frederic Weisbecker <frederic@kernel.org>, Cc: Josh Triplett <josh@joshtriplett.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: "Zhang, Qiang1" <qiang1.zhang@intel.com> To: rcu@vger.kernel.org --- include/linux/srcutree.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h index d4b7f3daf2f8..ee4f3ffa1cce 100644 --- a/include/linux/srcutree.h +++ b/include/linux/srcutree.h @@ -94,8 +94,16 @@ struct srcu_struct { /* Values for size state variable (->srcu_size_state). */ #define SRCU_SIZE_SMALL 0 #define SRCU_SIZE_ALLOC 1 +/* snp tree has been initialized */ #define SRCU_SIZE_WAIT_BARRIER 2 +/* In this state, any srcu_barrier(), which considers the system not using snp + * tree, has finished. + */ #define SRCU_SIZE_WAIT_CALL 3 +/* + * Before snp tree is used, there can be two GPs , each takes two seq snap values. + * Wait until CBS1 - CBS4 elapse so these callbacks finishes. + */ #define SRCU_SIZE_WAIT_CBS1 4 #define SRCU_SIZE_WAIT_CBS2 5 #define SRCU_SIZE_WAIT_CBS3 6 -- 2.31.1 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] srcu: Add comments for srcu_size_state 2022-12-23 13:02 [PATCH] srcu: Add comments for srcu_size_state Pingfan Liu @ 2023-01-04 20:43 ` Paul E. McKenney 2023-01-06 12:51 ` Pingfan Liu 0 siblings, 1 reply; 3+ messages in thread From: Paul E. McKenney @ 2023-01-04 20:43 UTC (permalink / raw) To: Pingfan Liu Cc: rcu, Lai Jiangshan, Frederic Weisbecker, Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Zhang, Qiang1 On Fri, Dec 23, 2022 at 09:02:28PM +0800, Pingfan Liu wrote: > Signed-off-by: Pingfan Liu <kernelfans@gmail.com> > Cc: Lai Jiangshan <jiangshanlai@gmail.com> > Cc: "Paul E. McKenney" <paulmck@kernel.org> > Cc: Frederic Weisbecker <frederic@kernel.org>, > Cc: Josh Triplett <josh@joshtriplett.org> > Cc: Steven Rostedt <rostedt@goodmis.org> > Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> > Cc: "Zhang, Qiang1" <qiang1.zhang@intel.com> > To: rcu@vger.kernel.org Queued, thank you! After the inevitable wordsmithing, it appears as follows. Could you please check it? (And yes, it does take advantage of 100 columns.) Thanx, Paul ------------------------------------------------------------------------ commit 9c473f0ef9eb8f3ac76d8295cfb4065a738b07a1 Author: Pingfan Liu <kernelfans@gmail.com> Date: Wed Jan 4 12:29:01 2023 -0800 srcu: Add comments for srcu_size_state The SRCU_SIZE_* names are not self-explanatory, so this commit therefore adds comments to the definitions. Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Frederic Weisbecker <frederic@kernel.org>, Cc: Josh Triplett <josh@joshtriplett.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: "Zhang, Qiang1" <qiang1.zhang@intel.com> To: rcu@vger.kernel.org Signed-off-by: Paul E. McKenney <paulmck@kernel.org> diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h index 558057b517b74..a6910805f9c51 100644 --- a/include/linux/srcutree.h +++ b/include/linux/srcutree.h @@ -92,16 +92,29 @@ struct srcu_struct { struct lockdep_map dep_map; }; -/* Values for size state variable (->srcu_size_state). */ -#define SRCU_SIZE_SMALL 0 -#define SRCU_SIZE_ALLOC 1 -#define SRCU_SIZE_WAIT_BARRIER 2 -#define SRCU_SIZE_WAIT_CALL 3 -#define SRCU_SIZE_WAIT_CBS1 4 -#define SRCU_SIZE_WAIT_CBS2 5 -#define SRCU_SIZE_WAIT_CBS3 6 -#define SRCU_SIZE_WAIT_CBS4 7 -#define SRCU_SIZE_BIG 8 +// Values for size state variable (->srcu_size_state). Once the state +// has been set to SRCU_SIZE_ALLOC, the grace-period code advances through +// this state machine one step per grace period until the SRCU_SIZE_BIG state +// is reached. Otherwise, the state machine remains in the SRCU_SIZE_SMALL +// state indefinitely. +#define SRCU_SIZE_SMALL 0 // No srcu_node combining tree, ->node == NULL +#define SRCU_SIZE_ALLOC 1 // An srcu_node tree is being allocated, initialized, + // and then referenced by ->node. It will not be used. +#define SRCU_SIZE_WAIT_BARRIER 2 // The srcu_node tree starts being used by everything + // except call_srcu(), especially by srcu_barrier(). + // By the end of this state, all CPUs and threads + // are aware of this tree's existence. +#define SRCU_SIZE_WAIT_CALL 3 // The srcu_node tree starts being used by call_srcu(). + // By the end of this state, all of the call_srcu() + // invocations that were running on a non-boot CPU + // and using the boot CPU's callback queue will have + // completed. +#define SRCU_SIZE_WAIT_CBS1 4 // Don't trust the ->srcu_have_cbs[] grace-period +#define SRCU_SIZE_WAIT_CBS2 5 // sequence elements or the ->srcu_data_have_cbs[] +#define SRCU_SIZE_WAIT_CBS3 6 // CPU-bitmask elements until all four elements of +#define SRCU_SIZE_WAIT_CBS4 7 // each array have been initialized. +#define SRCU_SIZE_BIG 8 // The srcu_node combining tree is fully initialized + // and all aspects of it are being put to use. /* Values for state variable (bottom bits of ->srcu_gp_seq). */ #define SRCU_STATE_IDLE 0 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] srcu: Add comments for srcu_size_state 2023-01-04 20:43 ` Paul E. McKenney @ 2023-01-06 12:51 ` Pingfan Liu 0 siblings, 0 replies; 3+ messages in thread From: Pingfan Liu @ 2023-01-06 12:51 UTC (permalink / raw) To: paulmck Cc: rcu, Lai Jiangshan, Frederic Weisbecker, Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Zhang, Qiang1 On Thu, Jan 5, 2023 at 4:43 AM Paul E. McKenney <paulmck@kernel.org> wrote: > > On Fri, Dec 23, 2022 at 09:02:28PM +0800, Pingfan Liu wrote: > > Signed-off-by: Pingfan Liu <kernelfans@gmail.com> > > Cc: Lai Jiangshan <jiangshanlai@gmail.com> > > Cc: "Paul E. McKenney" <paulmck@kernel.org> > > Cc: Frederic Weisbecker <frederic@kernel.org>, > > Cc: Josh Triplett <josh@joshtriplett.org> > > Cc: Steven Rostedt <rostedt@goodmis.org> > > Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> > > Cc: "Zhang, Qiang1" <qiang1.zhang@intel.com> > > To: rcu@vger.kernel.org > > Queued, thank you! > > After the inevitable wordsmithing, it appears as follows. Could you Sorry for the poor English expression. > please check it? (And yes, it does take advantage of 100 columns.) > It looks better to me. Thanks, Pingfan > Thanx, Paul > > ------------------------------------------------------------------------ > > commit 9c473f0ef9eb8f3ac76d8295cfb4065a738b07a1 > Author: Pingfan Liu <kernelfans@gmail.com> > Date: Wed Jan 4 12:29:01 2023 -0800 > > srcu: Add comments for srcu_size_state > > The SRCU_SIZE_* names are not self-explanatory, so this commit therefore > adds comments to the definitions. > > Signed-off-by: Pingfan Liu <kernelfans@gmail.com> > Cc: Lai Jiangshan <jiangshanlai@gmail.com> > Cc: "Paul E. McKenney" <paulmck@kernel.org> > Cc: Frederic Weisbecker <frederic@kernel.org>, > Cc: Josh Triplett <josh@joshtriplett.org> > Cc: Steven Rostedt <rostedt@goodmis.org> > Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> > Cc: "Zhang, Qiang1" <qiang1.zhang@intel.com> > To: rcu@vger.kernel.org > Signed-off-by: Paul E. McKenney <paulmck@kernel.org> > > diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h > index 558057b517b74..a6910805f9c51 100644 > --- a/include/linux/srcutree.h > +++ b/include/linux/srcutree.h > @@ -92,16 +92,29 @@ struct srcu_struct { > struct lockdep_map dep_map; > }; > > -/* Values for size state variable (->srcu_size_state). */ > -#define SRCU_SIZE_SMALL 0 > -#define SRCU_SIZE_ALLOC 1 > -#define SRCU_SIZE_WAIT_BARRIER 2 > -#define SRCU_SIZE_WAIT_CALL 3 > -#define SRCU_SIZE_WAIT_CBS1 4 > -#define SRCU_SIZE_WAIT_CBS2 5 > -#define SRCU_SIZE_WAIT_CBS3 6 > -#define SRCU_SIZE_WAIT_CBS4 7 > -#define SRCU_SIZE_BIG 8 > +// Values for size state variable (->srcu_size_state). Once the state > +// has been set to SRCU_SIZE_ALLOC, the grace-period code advances through > +// this state machine one step per grace period until the SRCU_SIZE_BIG state > +// is reached. Otherwise, the state machine remains in the SRCU_SIZE_SMALL > +// state indefinitely. > +#define SRCU_SIZE_SMALL 0 // No srcu_node combining tree, ->node == NULL > +#define SRCU_SIZE_ALLOC 1 // An srcu_node tree is being allocated, initialized, > + // and then referenced by ->node. It will not be used. > +#define SRCU_SIZE_WAIT_BARRIER 2 // The srcu_node tree starts being used by everything > + // except call_srcu(), especially by srcu_barrier(). > + // By the end of this state, all CPUs and threads > + // are aware of this tree's existence. > +#define SRCU_SIZE_WAIT_CALL 3 // The srcu_node tree starts being used by call_srcu(). > + // By the end of this state, all of the call_srcu() > + // invocations that were running on a non-boot CPU > + // and using the boot CPU's callback queue will have > + // completed. > +#define SRCU_SIZE_WAIT_CBS1 4 // Don't trust the ->srcu_have_cbs[] grace-period > +#define SRCU_SIZE_WAIT_CBS2 5 // sequence elements or the ->srcu_data_have_cbs[] > +#define SRCU_SIZE_WAIT_CBS3 6 // CPU-bitmask elements until all four elements of > +#define SRCU_SIZE_WAIT_CBS4 7 // each array have been initialized. > +#define SRCU_SIZE_BIG 8 // The srcu_node combining tree is fully initialized > + // and all aspects of it are being put to use. > > /* Values for state variable (bottom bits of ->srcu_gp_seq). */ > #define SRCU_STATE_IDLE 0 ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-01-06 12:51 UTC | newest] Thread overview: 3+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2022-12-23 13:02 [PATCH] srcu: Add comments for srcu_size_state Pingfan Liu 2023-01-04 20:43 ` Paul E. McKenney 2023-01-06 12:51 ` Pingfan Liu
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