* [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option @ 2014-09-21 16:49 Pranith Kumar 2014-09-22 16:25 ` Josh Triplett 0 siblings, 1 reply; 6+ messages in thread From: Pranith Kumar @ 2014-09-21 16:49 UTC (permalink / raw) To: Paul E. McKenney, Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan, open list PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after TINY_PREEMPT_RCU has been removed. This patch removes CONFIG_PREEMPT_RCU and uses CONFIG_TREE_PREEMPT_RCU in its place. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> --- arch/xtensa/configs/s6105_defconfig | 2 +- include/linux/init_task.h | 2 +- include/linux/rcupdate.h | 16 ++++++++-------- include/linux/sched.h | 10 +++++----- init/Kconfig | 6 ------ kernel/rcu/update.c | 4 ++-- tools/testing/selftests/rcutorture/doc/TINY_RCU.txt | 2 +- .../selftests/rcutorture/doc/TREE_RCU-kconfig.txt | 2 +- 8 files changed, 19 insertions(+), 25 deletions(-) diff --git a/arch/xtensa/configs/s6105_defconfig b/arch/xtensa/configs/s6105_defconfig index 12a492a..dab1a99 100644 --- a/arch/xtensa/configs/s6105_defconfig +++ b/arch/xtensa/configs/s6105_defconfig @@ -35,7 +35,7 @@ CONFIG_SYSVIPC_SYSCTL=y # # CONFIG_CLASSIC_RCU is not set # CONFIG_TREE_RCU is not set -CONFIG_PREEMPT_RCU=y +CONFIG_TREE_PREEMPT_RCU=y # CONFIG_RCU_TRACE is not set # CONFIG_TREE_RCU_TRACE is not set # CONFIG_PREEMPT_RCU_TRACE is not set diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 77fc43f..39600f4 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -108,7 +108,7 @@ extern struct group_info init_groups; #else #define INIT_TASK_RCU_TREE_PREEMPT(tsk) #endif -#ifdef CONFIG_PREEMPT_RCU +#ifdef CONFIG_TREE_PREEMPT_RCU #define INIT_TASK_RCU_PREEMPT(tsk) \ .rcu_read_lock_nesting = 0, \ .rcu_read_unlock_special.s = 0, \ diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index a4a819f..17a15d5 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -103,7 +103,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename, /* Exported common interfaces */ -#ifdef CONFIG_PREEMPT_RCU +#ifdef CONFIG_TREE_PREEMPT_RCU /** * call_rcu() - Queue an RCU callback for invocation after a grace period. @@ -140,12 +140,12 @@ void do_trace_rcu_torture_read(const char *rcutorturename, void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *head)); -#else /* #ifdef CONFIG_PREEMPT_RCU */ +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ /* In classic RCU, call_rcu() is just call_rcu_sched(). */ #define call_rcu call_rcu_sched -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ /** * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. @@ -217,7 +217,7 @@ void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head)); void synchronize_rcu_tasks(void); void rcu_barrier_tasks(void); -#ifdef CONFIG_PREEMPT_RCU +#ifdef CONFIG_TREE_PREEMPT_RCU void __rcu_read_lock(void); void __rcu_read_unlock(void); @@ -227,12 +227,12 @@ void synchronize_rcu(void); /* * Defined as a macro as it is a very low level header included from * areas that don't even know about current. This gives the rcu_read_lock() - * nesting depth, but makes sense only if CONFIG_PREEMPT_RCU -- in other + * nesting depth, but makes sense only if CONFIG_TREE_PREEMPT_RCU -- in other * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. */ #define rcu_preempt_depth() (current->rcu_read_lock_nesting) -#else /* #ifdef CONFIG_PREEMPT_RCU */ +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ static inline void __rcu_read_lock(void) { @@ -254,7 +254,7 @@ static inline int rcu_preempt_depth(void) return 0; } -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ /* Internal to kernel */ void rcu_init(void); @@ -530,7 +530,7 @@ static inline int rcu_read_lock_sched_held(void) } \ } while (0) -#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_PREEMPT_RCU) +#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_TREE_PREEMPT_RCU) static inline void rcu_preempt_sleep_check(void) { rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), diff --git a/include/linux/sched.h b/include/linux/sched.h index 42888d7..6acaa30 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1269,11 +1269,11 @@ struct task_struct { int nr_cpus_allowed; cpumask_t cpus_allowed; -#ifdef CONFIG_PREEMPT_RCU +#ifdef CONFIG_TREE_PREEMPT_RCU int rcu_read_lock_nesting; union rcu_special rcu_read_unlock_special; struct list_head rcu_node_entry; -#endif /* #ifdef CONFIG_PREEMPT_RCU */ +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ #ifdef CONFIG_TREE_PREEMPT_RCU struct rcu_node *rcu_blocked_node; #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ @@ -2014,12 +2014,12 @@ extern void task_clear_jobctl_pending(struct task_struct *task, static inline void rcu_copy_process(struct task_struct *p) { -#ifdef CONFIG_PREEMPT_RCU +#ifdef CONFIG_TREE_PREEMPT_RCU p->rcu_read_lock_nesting = 0; p->rcu_read_unlock_special.s = 0; p->rcu_blocked_node = NULL; INIT_LIST_HEAD(&p->rcu_node_entry); -#endif /* #ifdef CONFIG_PREEMPT_RCU */ +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ #ifdef CONFIG_TASKS_RCU p->rcu_tasks_holdout = false; INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); @@ -2752,7 +2752,7 @@ extern int __cond_resched_softirq(void); static inline void cond_resched_rcu(void) { -#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) +#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_TREE_PREEMPT_RCU) rcu_read_unlock(); cond_resched(); rcu_read_lock(); diff --git a/init/Kconfig b/init/Kconfig index 8a2b97c..27ad03c 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -501,12 +501,6 @@ config TINY_RCU endchoice -config PREEMPT_RCU - def_bool TREE_PREEMPT_RCU - help - This option enables preemptible-RCU code that is common between - TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU. - config TASKS_RCU bool "Task_based RCU implementation using voluntary context switch" default n diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 3ef8ba5..8848a32 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -62,7 +62,7 @@ MODULE_ALIAS("rcupdate"); module_param(rcu_expedited, int, 0); -#ifdef CONFIG_PREEMPT_RCU +#ifdef CONFIG_TREE_PREEMPT_RCU /* * Preemptible RCU implementation for rcu_read_lock(). @@ -108,7 +108,7 @@ void __rcu_read_unlock(void) } EXPORT_SYMBOL_GPL(__rcu_read_unlock); -#endif /* #ifdef CONFIG_PREEMPT_RCU */ +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key rcu_lock_key; diff --git a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt index 28db67b..4fea92d 100644 --- a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt +++ b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt @@ -31,7 +31,7 @@ CONFIG_RCU_TORTURE_TEST CONFIG_HOTPLUG_CPU CONFIG_PREEMPT -CONFIG_PREEMPT_RCU +CONFIG_TREE_PREEMPT_RCU CONFIG_SMP CONFIG_TINY_RCU CONFIG_TREE_PREEMPT_RCU diff --git a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt index f85c45e..081dece 100644 --- a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt +++ b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt @@ -62,7 +62,7 @@ CONFIG_NO_HZ_FULL_SYSIDLE_SMALL Defer until Frederic uses this. CONFIG_PREEMPT_COUNT -CONFIG_PREEMPT_RCU +CONFIG_TREE_PREEMPT_RCU Redundant with CONFIG_PREEMPT, ignore. -- 2.1.0 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option 2014-09-21 16:49 [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option Pranith Kumar @ 2014-09-22 16:25 ` Josh Triplett 2014-09-22 16:44 ` Paul E. McKenney 2014-09-22 16:49 ` Pranith Kumar 0 siblings, 2 replies; 6+ messages in thread From: Josh Triplett @ 2014-09-22 16:25 UTC (permalink / raw) To: Pranith Kumar Cc: Paul E. McKenney, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan, open list On Sun, Sep 21, 2014 at 12:49:54PM -0400, Pranith Kumar wrote: > PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after TINY_PREEMPT_RCU > has been removed. This patch removes CONFIG_PREEMPT_RCU and uses > CONFIG_TREE_PREEMPT_RCU in its place. > > Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> I think it would actually make more sense to do this the other way around, if at all: drop TREE_PREEMPT_RCU in favor of PREEMPT_RCU. The instances shown here don't care about *which* preemptible RCU implementation the kernel uses, they just need to behave differently when preemptible. Let's also not assume that no new RCU implementation will ever arise superceding TREE_PREEMPT_RCU. - Josh Triplett > arch/xtensa/configs/s6105_defconfig | 2 +- > include/linux/init_task.h | 2 +- > include/linux/rcupdate.h | 16 ++++++++-------- > include/linux/sched.h | 10 +++++----- > init/Kconfig | 6 ------ > kernel/rcu/update.c | 4 ++-- > tools/testing/selftests/rcutorture/doc/TINY_RCU.txt | 2 +- > .../selftests/rcutorture/doc/TREE_RCU-kconfig.txt | 2 +- > 8 files changed, 19 insertions(+), 25 deletions(-) > > diff --git a/arch/xtensa/configs/s6105_defconfig b/arch/xtensa/configs/s6105_defconfig > index 12a492a..dab1a99 100644 > --- a/arch/xtensa/configs/s6105_defconfig > +++ b/arch/xtensa/configs/s6105_defconfig > @@ -35,7 +35,7 @@ CONFIG_SYSVIPC_SYSCTL=y > # > # CONFIG_CLASSIC_RCU is not set > # CONFIG_TREE_RCU is not set > -CONFIG_PREEMPT_RCU=y > +CONFIG_TREE_PREEMPT_RCU=y > # CONFIG_RCU_TRACE is not set > # CONFIG_TREE_RCU_TRACE is not set > # CONFIG_PREEMPT_RCU_TRACE is not set > diff --git a/include/linux/init_task.h b/include/linux/init_task.h > index 77fc43f..39600f4 100644 > --- a/include/linux/init_task.h > +++ b/include/linux/init_task.h > @@ -108,7 +108,7 @@ extern struct group_info init_groups; > #else > #define INIT_TASK_RCU_TREE_PREEMPT(tsk) > #endif > -#ifdef CONFIG_PREEMPT_RCU > +#ifdef CONFIG_TREE_PREEMPT_RCU > #define INIT_TASK_RCU_PREEMPT(tsk) \ > .rcu_read_lock_nesting = 0, \ > .rcu_read_unlock_special.s = 0, \ > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > index a4a819f..17a15d5 100644 > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -103,7 +103,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename, > > /* Exported common interfaces */ > > -#ifdef CONFIG_PREEMPT_RCU > +#ifdef CONFIG_TREE_PREEMPT_RCU > > /** > * call_rcu() - Queue an RCU callback for invocation after a grace period. > @@ -140,12 +140,12 @@ void do_trace_rcu_torture_read(const char *rcutorturename, > void call_rcu(struct rcu_head *head, > void (*func)(struct rcu_head *head)); > > -#else /* #ifdef CONFIG_PREEMPT_RCU */ > +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > /* In classic RCU, call_rcu() is just call_rcu_sched(). */ > #define call_rcu call_rcu_sched > > -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ > +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ > > /** > * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. > @@ -217,7 +217,7 @@ void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head)); > void synchronize_rcu_tasks(void); > void rcu_barrier_tasks(void); > > -#ifdef CONFIG_PREEMPT_RCU > +#ifdef CONFIG_TREE_PREEMPT_RCU > > void __rcu_read_lock(void); > void __rcu_read_unlock(void); > @@ -227,12 +227,12 @@ void synchronize_rcu(void); > /* > * Defined as a macro as it is a very low level header included from > * areas that don't even know about current. This gives the rcu_read_lock() > - * nesting depth, but makes sense only if CONFIG_PREEMPT_RCU -- in other > + * nesting depth, but makes sense only if CONFIG_TREE_PREEMPT_RCU -- in other > * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. > */ > #define rcu_preempt_depth() (current->rcu_read_lock_nesting) > > -#else /* #ifdef CONFIG_PREEMPT_RCU */ > +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > static inline void __rcu_read_lock(void) > { > @@ -254,7 +254,7 @@ static inline int rcu_preempt_depth(void) > return 0; > } > > -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ > +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ > > /* Internal to kernel */ > void rcu_init(void); > @@ -530,7 +530,7 @@ static inline int rcu_read_lock_sched_held(void) > } \ > } while (0) > > -#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_PREEMPT_RCU) > +#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_TREE_PREEMPT_RCU) > static inline void rcu_preempt_sleep_check(void) > { > rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), > diff --git a/include/linux/sched.h b/include/linux/sched.h > index 42888d7..6acaa30 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -1269,11 +1269,11 @@ struct task_struct { > int nr_cpus_allowed; > cpumask_t cpus_allowed; > > -#ifdef CONFIG_PREEMPT_RCU > +#ifdef CONFIG_TREE_PREEMPT_RCU > int rcu_read_lock_nesting; > union rcu_special rcu_read_unlock_special; > struct list_head rcu_node_entry; > -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > #ifdef CONFIG_TREE_PREEMPT_RCU > struct rcu_node *rcu_blocked_node; > #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > @@ -2014,12 +2014,12 @@ extern void task_clear_jobctl_pending(struct task_struct *task, > > static inline void rcu_copy_process(struct task_struct *p) > { > -#ifdef CONFIG_PREEMPT_RCU > +#ifdef CONFIG_TREE_PREEMPT_RCU > p->rcu_read_lock_nesting = 0; > p->rcu_read_unlock_special.s = 0; > p->rcu_blocked_node = NULL; > INIT_LIST_HEAD(&p->rcu_node_entry); > -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > #ifdef CONFIG_TASKS_RCU > p->rcu_tasks_holdout = false; > INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); > @@ -2752,7 +2752,7 @@ extern int __cond_resched_softirq(void); > > static inline void cond_resched_rcu(void) > { > -#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) > +#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_TREE_PREEMPT_RCU) > rcu_read_unlock(); > cond_resched(); > rcu_read_lock(); > diff --git a/init/Kconfig b/init/Kconfig > index 8a2b97c..27ad03c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -501,12 +501,6 @@ config TINY_RCU > > endchoice > > -config PREEMPT_RCU > - def_bool TREE_PREEMPT_RCU > - help > - This option enables preemptible-RCU code that is common between > - TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU. > - > config TASKS_RCU > bool "Task_based RCU implementation using voluntary context switch" > default n > diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c > index 3ef8ba5..8848a32 100644 > --- a/kernel/rcu/update.c > +++ b/kernel/rcu/update.c > @@ -62,7 +62,7 @@ MODULE_ALIAS("rcupdate"); > > module_param(rcu_expedited, int, 0); > > -#ifdef CONFIG_PREEMPT_RCU > +#ifdef CONFIG_TREE_PREEMPT_RCU > > /* > * Preemptible RCU implementation for rcu_read_lock(). > @@ -108,7 +108,7 @@ void __rcu_read_unlock(void) > } > EXPORT_SYMBOL_GPL(__rcu_read_unlock); > > -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > #ifdef CONFIG_DEBUG_LOCK_ALLOC > static struct lock_class_key rcu_lock_key; > diff --git a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > index 28db67b..4fea92d 100644 > --- a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > +++ b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > @@ -31,7 +31,7 @@ CONFIG_RCU_TORTURE_TEST > > CONFIG_HOTPLUG_CPU > CONFIG_PREEMPT > -CONFIG_PREEMPT_RCU > +CONFIG_TREE_PREEMPT_RCU > CONFIG_SMP > CONFIG_TINY_RCU > CONFIG_TREE_PREEMPT_RCU > diff --git a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > index f85c45e..081dece 100644 > --- a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > +++ b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > @@ -62,7 +62,7 @@ CONFIG_NO_HZ_FULL_SYSIDLE_SMALL > Defer until Frederic uses this. > > CONFIG_PREEMPT_COUNT > -CONFIG_PREEMPT_RCU > +CONFIG_TREE_PREEMPT_RCU > > Redundant with CONFIG_PREEMPT, ignore. > > -- > 2.1.0 > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option 2014-09-22 16:25 ` Josh Triplett @ 2014-09-22 16:44 ` Paul E. McKenney 2014-09-22 16:49 ` Pranith Kumar 1 sibling, 0 replies; 6+ messages in thread From: Paul E. McKenney @ 2014-09-22 16:44 UTC (permalink / raw) To: Josh Triplett Cc: Pranith Kumar, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan, open list On Mon, Sep 22, 2014 at 09:25:34AM -0700, Josh Triplett wrote: > On Sun, Sep 21, 2014 at 12:49:54PM -0400, Pranith Kumar wrote: > > PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after TINY_PREEMPT_RCU > > has been removed. This patch removes CONFIG_PREEMPT_RCU and uses > > CONFIG_TREE_PREEMPT_RCU in its place. > > > > Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> > > I think it would actually make more sense to do this the other way > around, if at all: drop TREE_PREEMPT_RCU in favor of PREEMPT_RCU. The > instances shown here don't care about *which* preemptible RCU > implementation the kernel uses, they just need to behave differently > when preemptible. Let's also not assume that no new RCU implementation > will ever arise superceding TREE_PREEMPT_RCU. Given that there has thus far been no fewer than three distinct implementations of PREEMPT_RCU (one in -rt, the first in mainline, and the current one in mainline), it would indeed be quite wise to avoid assuming that there never will be some new PREEMPT_RCU implementation. ;-) Thanx, Paul > - Josh Triplett > > > arch/xtensa/configs/s6105_defconfig | 2 +- > > include/linux/init_task.h | 2 +- > > include/linux/rcupdate.h | 16 ++++++++-------- > > include/linux/sched.h | 10 +++++----- > > init/Kconfig | 6 ------ > > kernel/rcu/update.c | 4 ++-- > > tools/testing/selftests/rcutorture/doc/TINY_RCU.txt | 2 +- > > .../selftests/rcutorture/doc/TREE_RCU-kconfig.txt | 2 +- > > 8 files changed, 19 insertions(+), 25 deletions(-) > > > > diff --git a/arch/xtensa/configs/s6105_defconfig b/arch/xtensa/configs/s6105_defconfig > > index 12a492a..dab1a99 100644 > > --- a/arch/xtensa/configs/s6105_defconfig > > +++ b/arch/xtensa/configs/s6105_defconfig > > @@ -35,7 +35,7 @@ CONFIG_SYSVIPC_SYSCTL=y > > # > > # CONFIG_CLASSIC_RCU is not set > > # CONFIG_TREE_RCU is not set > > -CONFIG_PREEMPT_RCU=y > > +CONFIG_TREE_PREEMPT_RCU=y > > # CONFIG_RCU_TRACE is not set > > # CONFIG_TREE_RCU_TRACE is not set > > # CONFIG_PREEMPT_RCU_TRACE is not set > > diff --git a/include/linux/init_task.h b/include/linux/init_task.h > > index 77fc43f..39600f4 100644 > > --- a/include/linux/init_task.h > > +++ b/include/linux/init_task.h > > @@ -108,7 +108,7 @@ extern struct group_info init_groups; > > #else > > #define INIT_TASK_RCU_TREE_PREEMPT(tsk) > > #endif > > -#ifdef CONFIG_PREEMPT_RCU > > +#ifdef CONFIG_TREE_PREEMPT_RCU > > #define INIT_TASK_RCU_PREEMPT(tsk) \ > > .rcu_read_lock_nesting = 0, \ > > .rcu_read_unlock_special.s = 0, \ > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > index a4a819f..17a15d5 100644 > > --- a/include/linux/rcupdate.h > > +++ b/include/linux/rcupdate.h > > @@ -103,7 +103,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename, > > > > /* Exported common interfaces */ > > > > -#ifdef CONFIG_PREEMPT_RCU > > +#ifdef CONFIG_TREE_PREEMPT_RCU > > > > /** > > * call_rcu() - Queue an RCU callback for invocation after a grace period. > > @@ -140,12 +140,12 @@ void do_trace_rcu_torture_read(const char *rcutorturename, > > void call_rcu(struct rcu_head *head, > > void (*func)(struct rcu_head *head)); > > > > -#else /* #ifdef CONFIG_PREEMPT_RCU */ > > +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > > > /* In classic RCU, call_rcu() is just call_rcu_sched(). */ > > #define call_rcu call_rcu_sched > > > > -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ > > +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ > > > > /** > > * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. > > @@ -217,7 +217,7 @@ void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head)); > > void synchronize_rcu_tasks(void); > > void rcu_barrier_tasks(void); > > > > -#ifdef CONFIG_PREEMPT_RCU > > +#ifdef CONFIG_TREE_PREEMPT_RCU > > > > void __rcu_read_lock(void); > > void __rcu_read_unlock(void); > > @@ -227,12 +227,12 @@ void synchronize_rcu(void); > > /* > > * Defined as a macro as it is a very low level header included from > > * areas that don't even know about current. This gives the rcu_read_lock() > > - * nesting depth, but makes sense only if CONFIG_PREEMPT_RCU -- in other > > + * nesting depth, but makes sense only if CONFIG_TREE_PREEMPT_RCU -- in other > > * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. > > */ > > #define rcu_preempt_depth() (current->rcu_read_lock_nesting) > > > > -#else /* #ifdef CONFIG_PREEMPT_RCU */ > > +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > > > static inline void __rcu_read_lock(void) > > { > > @@ -254,7 +254,7 @@ static inline int rcu_preempt_depth(void) > > return 0; > > } > > > > -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ > > +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ > > > > /* Internal to kernel */ > > void rcu_init(void); > > @@ -530,7 +530,7 @@ static inline int rcu_read_lock_sched_held(void) > > } \ > > } while (0) > > > > -#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_PREEMPT_RCU) > > +#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_TREE_PREEMPT_RCU) > > static inline void rcu_preempt_sleep_check(void) > > { > > rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), > > diff --git a/include/linux/sched.h b/include/linux/sched.h > > index 42888d7..6acaa30 100644 > > --- a/include/linux/sched.h > > +++ b/include/linux/sched.h > > @@ -1269,11 +1269,11 @@ struct task_struct { > > int nr_cpus_allowed; > > cpumask_t cpus_allowed; > > > > -#ifdef CONFIG_PREEMPT_RCU > > +#ifdef CONFIG_TREE_PREEMPT_RCU > > int rcu_read_lock_nesting; > > union rcu_special rcu_read_unlock_special; > > struct list_head rcu_node_entry; > > -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > > +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > #ifdef CONFIG_TREE_PREEMPT_RCU > > struct rcu_node *rcu_blocked_node; > > #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > @@ -2014,12 +2014,12 @@ extern void task_clear_jobctl_pending(struct task_struct *task, > > > > static inline void rcu_copy_process(struct task_struct *p) > > { > > -#ifdef CONFIG_PREEMPT_RCU > > +#ifdef CONFIG_TREE_PREEMPT_RCU > > p->rcu_read_lock_nesting = 0; > > p->rcu_read_unlock_special.s = 0; > > p->rcu_blocked_node = NULL; > > INIT_LIST_HEAD(&p->rcu_node_entry); > > -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > > +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > #ifdef CONFIG_TASKS_RCU > > p->rcu_tasks_holdout = false; > > INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); > > @@ -2752,7 +2752,7 @@ extern int __cond_resched_softirq(void); > > > > static inline void cond_resched_rcu(void) > > { > > -#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) > > +#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_TREE_PREEMPT_RCU) > > rcu_read_unlock(); > > cond_resched(); > > rcu_read_lock(); > > diff --git a/init/Kconfig b/init/Kconfig > > index 8a2b97c..27ad03c 100644 > > --- a/init/Kconfig > > +++ b/init/Kconfig > > @@ -501,12 +501,6 @@ config TINY_RCU > > > > endchoice > > > > -config PREEMPT_RCU > > - def_bool TREE_PREEMPT_RCU > > - help > > - This option enables preemptible-RCU code that is common between > > - TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU. > > - > > config TASKS_RCU > > bool "Task_based RCU implementation using voluntary context switch" > > default n > > diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c > > index 3ef8ba5..8848a32 100644 > > --- a/kernel/rcu/update.c > > +++ b/kernel/rcu/update.c > > @@ -62,7 +62,7 @@ MODULE_ALIAS("rcupdate"); > > > > module_param(rcu_expedited, int, 0); > > > > -#ifdef CONFIG_PREEMPT_RCU > > +#ifdef CONFIG_TREE_PREEMPT_RCU > > > > /* > > * Preemptible RCU implementation for rcu_read_lock(). > > @@ -108,7 +108,7 @@ void __rcu_read_unlock(void) > > } > > EXPORT_SYMBOL_GPL(__rcu_read_unlock); > > > > -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > > +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > > > > #ifdef CONFIG_DEBUG_LOCK_ALLOC > > static struct lock_class_key rcu_lock_key; > > diff --git a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > > index 28db67b..4fea92d 100644 > > --- a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > > +++ b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > > @@ -31,7 +31,7 @@ CONFIG_RCU_TORTURE_TEST > > > > CONFIG_HOTPLUG_CPU > > CONFIG_PREEMPT > > -CONFIG_PREEMPT_RCU > > +CONFIG_TREE_PREEMPT_RCU > > CONFIG_SMP > > CONFIG_TINY_RCU > > CONFIG_TREE_PREEMPT_RCU > > diff --git a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > > index f85c45e..081dece 100644 > > --- a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > > +++ b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > > @@ -62,7 +62,7 @@ CONFIG_NO_HZ_FULL_SYSIDLE_SMALL > > Defer until Frederic uses this. > > > > CONFIG_PREEMPT_COUNT > > -CONFIG_PREEMPT_RCU > > +CONFIG_TREE_PREEMPT_RCU > > > > Redundant with CONFIG_PREEMPT, ignore. > > > > -- > > 2.1.0 > > > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option 2014-09-22 16:25 ` Josh Triplett 2014-09-22 16:44 ` Paul E. McKenney @ 2014-09-22 16:49 ` Pranith Kumar 2014-09-22 17:01 ` Paul E. McKenney 1 sibling, 1 reply; 6+ messages in thread From: Pranith Kumar @ 2014-09-22 16:49 UTC (permalink / raw) To: Josh Triplett Cc: Paul E. McKenney, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan, open list On Mon, Sep 22, 2014 at 12:25 PM, Josh Triplett <josh@joshtriplett.org> wrote: > On Sun, Sep 21, 2014 at 12:49:54PM -0400, Pranith Kumar wrote: >> PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after TINY_PREEMPT_RCU >> has been removed. This patch removes CONFIG_PREEMPT_RCU and uses >> CONFIG_TREE_PREEMPT_RCU in its place. >> >> Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> > > I think it would actually make more sense to do this the other way > around, if at all: drop TREE_PREEMPT_RCU in favor of PREEMPT_RCU. The > instances shown here don't care about *which* preemptible RCU > implementation the kernel uses, they just need to behave differently > when preemptible. Let's also not assume that no new RCU implementation > will ever arise superceding TREE_PREEMPT_RCU. That is exactly what I did first and got the following changelog: 51 files changed, 77 insertions(+), 83 deletions(-) compared to 8 files changed, 19 insertions(+), 25 deletions(-) for the current one. Hence my patch opting for the latter. I will go ahead and send the other patch. >> 8 files changed, 19 insertions(+), 25 deletions(-) >> >> diff --git a/arch/xtensa/configs/s6105_defconfig b/arch/xtensa/configs/s6105_defconfig >> index 12a492a..dab1a99 100644 >> --- a/arch/xtensa/configs/s6105_defconfig >> +++ b/arch/xtensa/configs/s6105_defconfig >> @@ -35,7 +35,7 @@ CONFIG_SYSVIPC_SYSCTL=y >> # >> # CONFIG_CLASSIC_RCU is not set >> # CONFIG_TREE_RCU is not set >> -CONFIG_PREEMPT_RCU=y >> +CONFIG_TREE_PREEMPT_RCU=y >> # CONFIG_RCU_TRACE is not set >> # CONFIG_TREE_RCU_TRACE is not set >> # CONFIG_PREEMPT_RCU_TRACE is not set >> diff --git a/include/linux/init_task.h b/include/linux/init_task.h >> index 77fc43f..39600f4 100644 >> --- a/include/linux/init_task.h >> +++ b/include/linux/init_task.h >> @@ -108,7 +108,7 @@ extern struct group_info init_groups; >> #else >> #define INIT_TASK_RCU_TREE_PREEMPT(tsk) >> #endif >> -#ifdef CONFIG_PREEMPT_RCU >> +#ifdef CONFIG_TREE_PREEMPT_RCU >> #define INIT_TASK_RCU_PREEMPT(tsk) \ >> .rcu_read_lock_nesting = 0, \ >> .rcu_read_unlock_special.s = 0, \ >> diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h >> index a4a819f..17a15d5 100644 >> --- a/include/linux/rcupdate.h >> +++ b/include/linux/rcupdate.h >> @@ -103,7 +103,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename, >> >> /* Exported common interfaces */ >> >> -#ifdef CONFIG_PREEMPT_RCU >> +#ifdef CONFIG_TREE_PREEMPT_RCU >> >> /** >> * call_rcu() - Queue an RCU callback for invocation after a grace period. >> @@ -140,12 +140,12 @@ void do_trace_rcu_torture_read(const char *rcutorturename, >> void call_rcu(struct rcu_head *head, >> void (*func)(struct rcu_head *head)); >> >> -#else /* #ifdef CONFIG_PREEMPT_RCU */ >> +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ >> >> /* In classic RCU, call_rcu() is just call_rcu_sched(). */ >> #define call_rcu call_rcu_sched >> >> -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ >> +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ >> >> /** >> * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. >> @@ -217,7 +217,7 @@ void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head)); >> void synchronize_rcu_tasks(void); >> void rcu_barrier_tasks(void); >> >> -#ifdef CONFIG_PREEMPT_RCU >> +#ifdef CONFIG_TREE_PREEMPT_RCU >> >> void __rcu_read_lock(void); >> void __rcu_read_unlock(void); >> @@ -227,12 +227,12 @@ void synchronize_rcu(void); >> /* >> * Defined as a macro as it is a very low level header included from >> * areas that don't even know about current. This gives the rcu_read_lock() >> - * nesting depth, but makes sense only if CONFIG_PREEMPT_RCU -- in other >> + * nesting depth, but makes sense only if CONFIG_TREE_PREEMPT_RCU -- in other >> * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. >> */ >> #define rcu_preempt_depth() (current->rcu_read_lock_nesting) >> >> -#else /* #ifdef CONFIG_PREEMPT_RCU */ >> +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ >> >> static inline void __rcu_read_lock(void) >> { >> @@ -254,7 +254,7 @@ static inline int rcu_preempt_depth(void) >> return 0; >> } >> >> -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ >> +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ >> >> /* Internal to kernel */ >> void rcu_init(void); >> @@ -530,7 +530,7 @@ static inline int rcu_read_lock_sched_held(void) >> } \ >> } while (0) >> >> -#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_PREEMPT_RCU) >> +#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_TREE_PREEMPT_RCU) >> static inline void rcu_preempt_sleep_check(void) >> { >> rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), >> diff --git a/include/linux/sched.h b/include/linux/sched.h >> index 42888d7..6acaa30 100644 >> --- a/include/linux/sched.h >> +++ b/include/linux/sched.h >> @@ -1269,11 +1269,11 @@ struct task_struct { >> int nr_cpus_allowed; >> cpumask_t cpus_allowed; >> >> -#ifdef CONFIG_PREEMPT_RCU >> +#ifdef CONFIG_TREE_PREEMPT_RCU >> int rcu_read_lock_nesting; >> union rcu_special rcu_read_unlock_special; >> struct list_head rcu_node_entry; >> -#endif /* #ifdef CONFIG_PREEMPT_RCU */ >> +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ >> #ifdef CONFIG_TREE_PREEMPT_RCU >> struct rcu_node *rcu_blocked_node; >> #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ >> @@ -2014,12 +2014,12 @@ extern void task_clear_jobctl_pending(struct task_struct *task, >> >> static inline void rcu_copy_process(struct task_struct *p) >> { >> -#ifdef CONFIG_PREEMPT_RCU >> +#ifdef CONFIG_TREE_PREEMPT_RCU >> p->rcu_read_lock_nesting = 0; >> p->rcu_read_unlock_special.s = 0; >> p->rcu_blocked_node = NULL; >> INIT_LIST_HEAD(&p->rcu_node_entry); >> -#endif /* #ifdef CONFIG_PREEMPT_RCU */ >> +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ >> #ifdef CONFIG_TASKS_RCU >> p->rcu_tasks_holdout = false; >> INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); >> @@ -2752,7 +2752,7 @@ extern int __cond_resched_softirq(void); >> >> static inline void cond_resched_rcu(void) >> { >> -#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) >> +#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_TREE_PREEMPT_RCU) >> rcu_read_unlock(); >> cond_resched(); >> rcu_read_lock(); >> diff --git a/init/Kconfig b/init/Kconfig >> index 8a2b97c..27ad03c 100644 >> --- a/init/Kconfig >> +++ b/init/Kconfig >> @@ -501,12 +501,6 @@ config TINY_RCU >> >> endchoice >> >> -config PREEMPT_RCU >> - def_bool TREE_PREEMPT_RCU >> - help >> - This option enables preemptible-RCU code that is common between >> - TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU. >> - >> config TASKS_RCU >> bool "Task_based RCU implementation using voluntary context switch" >> default n >> diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c >> index 3ef8ba5..8848a32 100644 >> --- a/kernel/rcu/update.c >> +++ b/kernel/rcu/update.c >> @@ -62,7 +62,7 @@ MODULE_ALIAS("rcupdate"); >> >> module_param(rcu_expedited, int, 0); >> >> -#ifdef CONFIG_PREEMPT_RCU >> +#ifdef CONFIG_TREE_PREEMPT_RCU >> >> /* >> * Preemptible RCU implementation for rcu_read_lock(). >> @@ -108,7 +108,7 @@ void __rcu_read_unlock(void) >> } >> EXPORT_SYMBOL_GPL(__rcu_read_unlock); >> >> -#endif /* #ifdef CONFIG_PREEMPT_RCU */ >> +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ >> >> #ifdef CONFIG_DEBUG_LOCK_ALLOC >> static struct lock_class_key rcu_lock_key; >> diff --git a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt >> index 28db67b..4fea92d 100644 >> --- a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt >> +++ b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt >> @@ -31,7 +31,7 @@ CONFIG_RCU_TORTURE_TEST >> >> CONFIG_HOTPLUG_CPU >> CONFIG_PREEMPT >> -CONFIG_PREEMPT_RCU >> +CONFIG_TREE_PREEMPT_RCU >> CONFIG_SMP >> CONFIG_TINY_RCU >> CONFIG_TREE_PREEMPT_RCU >> diff --git a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt >> index f85c45e..081dece 100644 >> --- a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt >> +++ b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt >> @@ -62,7 +62,7 @@ CONFIG_NO_HZ_FULL_SYSIDLE_SMALL >> Defer until Frederic uses this. >> >> CONFIG_PREEMPT_COUNT >> -CONFIG_PREEMPT_RCU >> +CONFIG_TREE_PREEMPT_RCU >> >> Redundant with CONFIG_PREEMPT, ignore. >> >> -- >> 2.1.0 >> -- Pranith ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option 2014-09-22 16:49 ` Pranith Kumar @ 2014-09-22 17:01 ` Paul E. McKenney 2014-09-22 17:44 ` Pranith Kumar 0 siblings, 1 reply; 6+ messages in thread From: Paul E. McKenney @ 2014-09-22 17:01 UTC (permalink / raw) To: Pranith Kumar Cc: Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan, open list On Mon, Sep 22, 2014 at 12:49:24PM -0400, Pranith Kumar wrote: > On Mon, Sep 22, 2014 at 12:25 PM, Josh Triplett <josh@joshtriplett.org> wrote: > > On Sun, Sep 21, 2014 at 12:49:54PM -0400, Pranith Kumar wrote: > >> PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after TINY_PREEMPT_RCU > >> has been removed. This patch removes CONFIG_PREEMPT_RCU and uses > >> CONFIG_TREE_PREEMPT_RCU in its place. > >> > >> Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> > > > > I think it would actually make more sense to do this the other way > > around, if at all: drop TREE_PREEMPT_RCU in favor of PREEMPT_RCU. The > > instances shown here don't care about *which* preemptible RCU > > implementation the kernel uses, they just need to behave differently > > when preemptible. Let's also not assume that no new RCU implementation > > will ever arise superceding TREE_PREEMPT_RCU. > > That is exactly what I did first and got the following changelog: > > 51 files changed, 77 insertions(+), 83 deletions(-) > > compared to > > 8 files changed, 19 insertions(+), 25 deletions(-) Were the bulk of the files defconfig files? These need not be changed, the architecture maintainers handle them. Thanx, Paul > for the current one. Hence my patch opting for the latter. I will go > ahead and send the other patch. > > >> 8 files changed, 19 insertions(+), 25 deletions(-) > >> > >> diff --git a/arch/xtensa/configs/s6105_defconfig b/arch/xtensa/configs/s6105_defconfig > >> index 12a492a..dab1a99 100644 > >> --- a/arch/xtensa/configs/s6105_defconfig > >> +++ b/arch/xtensa/configs/s6105_defconfig > >> @@ -35,7 +35,7 @@ CONFIG_SYSVIPC_SYSCTL=y > >> # > >> # CONFIG_CLASSIC_RCU is not set > >> # CONFIG_TREE_RCU is not set > >> -CONFIG_PREEMPT_RCU=y > >> +CONFIG_TREE_PREEMPT_RCU=y > >> # CONFIG_RCU_TRACE is not set > >> # CONFIG_TREE_RCU_TRACE is not set > >> # CONFIG_PREEMPT_RCU_TRACE is not set > >> diff --git a/include/linux/init_task.h b/include/linux/init_task.h > >> index 77fc43f..39600f4 100644 > >> --- a/include/linux/init_task.h > >> +++ b/include/linux/init_task.h > >> @@ -108,7 +108,7 @@ extern struct group_info init_groups; > >> #else > >> #define INIT_TASK_RCU_TREE_PREEMPT(tsk) > >> #endif > >> -#ifdef CONFIG_PREEMPT_RCU > >> +#ifdef CONFIG_TREE_PREEMPT_RCU > >> #define INIT_TASK_RCU_PREEMPT(tsk) \ > >> .rcu_read_lock_nesting = 0, \ > >> .rcu_read_unlock_special.s = 0, \ > >> diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > >> index a4a819f..17a15d5 100644 > >> --- a/include/linux/rcupdate.h > >> +++ b/include/linux/rcupdate.h > >> @@ -103,7 +103,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename, > >> > >> /* Exported common interfaces */ > >> > >> -#ifdef CONFIG_PREEMPT_RCU > >> +#ifdef CONFIG_TREE_PREEMPT_RCU > >> > >> /** > >> * call_rcu() - Queue an RCU callback for invocation after a grace period. > >> @@ -140,12 +140,12 @@ void do_trace_rcu_torture_read(const char *rcutorturename, > >> void call_rcu(struct rcu_head *head, > >> void (*func)(struct rcu_head *head)); > >> > >> -#else /* #ifdef CONFIG_PREEMPT_RCU */ > >> +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> > >> /* In classic RCU, call_rcu() is just call_rcu_sched(). */ > >> #define call_rcu call_rcu_sched > >> > >> -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ > >> +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> > >> /** > >> * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. > >> @@ -217,7 +217,7 @@ void call_rcu_tasks(struct rcu_head *head, void (*func)(struct rcu_head *head)); > >> void synchronize_rcu_tasks(void); > >> void rcu_barrier_tasks(void); > >> > >> -#ifdef CONFIG_PREEMPT_RCU > >> +#ifdef CONFIG_TREE_PREEMPT_RCU > >> > >> void __rcu_read_lock(void); > >> void __rcu_read_unlock(void); > >> @@ -227,12 +227,12 @@ void synchronize_rcu(void); > >> /* > >> * Defined as a macro as it is a very low level header included from > >> * areas that don't even know about current. This gives the rcu_read_lock() > >> - * nesting depth, but makes sense only if CONFIG_PREEMPT_RCU -- in other > >> + * nesting depth, but makes sense only if CONFIG_TREE_PREEMPT_RCU -- in other > >> * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. > >> */ > >> #define rcu_preempt_depth() (current->rcu_read_lock_nesting) > >> > >> -#else /* #ifdef CONFIG_PREEMPT_RCU */ > >> +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> > >> static inline void __rcu_read_lock(void) > >> { > >> @@ -254,7 +254,7 @@ static inline int rcu_preempt_depth(void) > >> return 0; > >> } > >> > >> -#endif /* #else #ifdef CONFIG_PREEMPT_RCU */ > >> +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> > >> /* Internal to kernel */ > >> void rcu_init(void); > >> @@ -530,7 +530,7 @@ static inline int rcu_read_lock_sched_held(void) > >> } \ > >> } while (0) > >> > >> -#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_PREEMPT_RCU) > >> +#if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_TREE_PREEMPT_RCU) > >> static inline void rcu_preempt_sleep_check(void) > >> { > >> rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), > >> diff --git a/include/linux/sched.h b/include/linux/sched.h > >> index 42888d7..6acaa30 100644 > >> --- a/include/linux/sched.h > >> +++ b/include/linux/sched.h > >> @@ -1269,11 +1269,11 @@ struct task_struct { > >> int nr_cpus_allowed; > >> cpumask_t cpus_allowed; > >> > >> -#ifdef CONFIG_PREEMPT_RCU > >> +#ifdef CONFIG_TREE_PREEMPT_RCU > >> int rcu_read_lock_nesting; > >> union rcu_special rcu_read_unlock_special; > >> struct list_head rcu_node_entry; > >> -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > >> +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> #ifdef CONFIG_TREE_PREEMPT_RCU > >> struct rcu_node *rcu_blocked_node; > >> #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> @@ -2014,12 +2014,12 @@ extern void task_clear_jobctl_pending(struct task_struct *task, > >> > >> static inline void rcu_copy_process(struct task_struct *p) > >> { > >> -#ifdef CONFIG_PREEMPT_RCU > >> +#ifdef CONFIG_TREE_PREEMPT_RCU > >> p->rcu_read_lock_nesting = 0; > >> p->rcu_read_unlock_special.s = 0; > >> p->rcu_blocked_node = NULL; > >> INIT_LIST_HEAD(&p->rcu_node_entry); > >> -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > >> +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> #ifdef CONFIG_TASKS_RCU > >> p->rcu_tasks_holdout = false; > >> INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); > >> @@ -2752,7 +2752,7 @@ extern int __cond_resched_softirq(void); > >> > >> static inline void cond_resched_rcu(void) > >> { > >> -#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) > >> +#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_TREE_PREEMPT_RCU) > >> rcu_read_unlock(); > >> cond_resched(); > >> rcu_read_lock(); > >> diff --git a/init/Kconfig b/init/Kconfig > >> index 8a2b97c..27ad03c 100644 > >> --- a/init/Kconfig > >> +++ b/init/Kconfig > >> @@ -501,12 +501,6 @@ config TINY_RCU > >> > >> endchoice > >> > >> -config PREEMPT_RCU > >> - def_bool TREE_PREEMPT_RCU > >> - help > >> - This option enables preemptible-RCU code that is common between > >> - TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU. > >> - > >> config TASKS_RCU > >> bool "Task_based RCU implementation using voluntary context switch" > >> default n > >> diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c > >> index 3ef8ba5..8848a32 100644 > >> --- a/kernel/rcu/update.c > >> +++ b/kernel/rcu/update.c > >> @@ -62,7 +62,7 @@ MODULE_ALIAS("rcupdate"); > >> > >> module_param(rcu_expedited, int, 0); > >> > >> -#ifdef CONFIG_PREEMPT_RCU > >> +#ifdef CONFIG_TREE_PREEMPT_RCU > >> > >> /* > >> * Preemptible RCU implementation for rcu_read_lock(). > >> @@ -108,7 +108,7 @@ void __rcu_read_unlock(void) > >> } > >> EXPORT_SYMBOL_GPL(__rcu_read_unlock); > >> > >> -#endif /* #ifdef CONFIG_PREEMPT_RCU */ > >> +#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ > >> > >> #ifdef CONFIG_DEBUG_LOCK_ALLOC > >> static struct lock_class_key rcu_lock_key; > >> diff --git a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > >> index 28db67b..4fea92d 100644 > >> --- a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > >> +++ b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt > >> @@ -31,7 +31,7 @@ CONFIG_RCU_TORTURE_TEST > >> > >> CONFIG_HOTPLUG_CPU > >> CONFIG_PREEMPT > >> -CONFIG_PREEMPT_RCU > >> +CONFIG_TREE_PREEMPT_RCU > >> CONFIG_SMP > >> CONFIG_TINY_RCU > >> CONFIG_TREE_PREEMPT_RCU > >> diff --git a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > >> index f85c45e..081dece 100644 > >> --- a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > >> +++ b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt > >> @@ -62,7 +62,7 @@ CONFIG_NO_HZ_FULL_SYSIDLE_SMALL > >> Defer until Frederic uses this. > >> > >> CONFIG_PREEMPT_COUNT > >> -CONFIG_PREEMPT_RCU > >> +CONFIG_TREE_PREEMPT_RCU > >> > >> Redundant with CONFIG_PREEMPT, ignore. > >> > >> -- > >> 2.1.0 > >> > > > > -- > Pranith > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option 2014-09-22 17:01 ` Paul E. McKenney @ 2014-09-22 17:44 ` Pranith Kumar 0 siblings, 0 replies; 6+ messages in thread From: Pranith Kumar @ 2014-09-22 17:44 UTC (permalink / raw) To: Paul McKenney Cc: Josh Triplett, Steven Rostedt, Mathieu Desnoyers, Lai Jiangshan, open list On Mon, Sep 22, 2014 at 1:01 PM, Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote: > On Mon, Sep 22, 2014 at 12:49:24PM -0400, Pranith Kumar wrote: >> On Mon, Sep 22, 2014 at 12:25 PM, Josh Triplett <josh@joshtriplett.org> wrote: >> > >> > I think it would actually make more sense to do this the other way >> > around, if at all: drop TREE_PREEMPT_RCU in favor of PREEMPT_RCU. The >> > instances shown here don't care about *which* preemptible RCU >> > implementation the kernel uses, they just need to behave differently >> > when preemptible. Let's also not assume that no new RCU implementation >> > will ever arise superceding TREE_PREEMPT_RCU. >> >> That is exactly what I did first and got the following changelog: >> >> 51 files changed, 77 insertions(+), 83 deletions(-) >> >> compared to >> >> 8 files changed, 19 insertions(+), 25 deletions(-) > > Were the bulk of the files defconfig files? These need not be changed, > the architecture maintainers handle them. > There are only two defconfig files in there. I removed them now. Most of them are rcutorture config files. I guess that should be fine. I am sending the patch now. -- Pranith ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2014-09-22 17:44 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2014-09-21 16:49 [PATCH] rcu: Remove redundant CONFIG_PREEMPT_RCU option Pranith Kumar 2014-09-22 16:25 ` Josh Triplett 2014-09-22 16:44 ` Paul E. McKenney 2014-09-22 16:49 ` Pranith Kumar 2014-09-22 17:01 ` Paul E. McKenney 2014-09-22 17:44 ` Pranith Kumar
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).