From 87de1cfdc55b16b794e245b07322340725149d62 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 3 Dec 2013 10:02:52 -0800 Subject: rcu: Stop tracking FSF's postal address All of the RCU source files have the usual GPL header, which contains a long-obsolete postal address for FSF. To avoid the need to track the FSF office's movements, this commit substitutes the URL where GPL may be found. Reported-by: Greg KH Reported-by: Steven Rostedt Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rcupdate.h | 4 ++-- include/linux/rcutiny.h | 4 ++-- include/linux/rcutree.h | 4 ++-- include/linux/srcu.h | 4 ++-- 4 files changed, 8 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 72bf3a01a4ee..b200756ea4c0 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -12,8 +12,8 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. * * Copyright IBM Corporation, 2001 * diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index 6f01771b571c..c364e9148de2 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -12,8 +12,8 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. * * Copyright IBM Corporation, 2008 * diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index 72137ee8c603..08b084068967 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -12,8 +12,8 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. * * Copyright IBM Corporation, 2008 * diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 9b058eecd403..a2783cb5d275 100644 --- a/include/linux/srcu.h +++ b/include/linux/srcu.h @@ -12,8 +12,8 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. * * Copyright (C) IBM Corporation, 2006 * Copyright (C) Fujitsu, 2012 -- cgit v1.2.3 From 41f4abd92a34f9c5110bbb870c04f8854604e28d Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Thu, 5 Dec 2013 15:10:23 -0800 Subject: rcu: Glue ASCII strings together Split strings make it difficult to find the code that resulted in a given console message, so this commit glues split strings back together despite the resulting long lines. Signed-off-by: Joe Perches Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rcupdate.h | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index b200756ea4c0..d946d3660633 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -479,11 +479,9 @@ static inline void rcu_preempt_sleep_check(void) do { \ rcu_preempt_sleep_check(); \ rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map), \ - "Illegal context switch in RCU-bh" \ - " read-side critical section"); \ + "Illegal context switch in RCU-bh read-side critical section"); \ rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map), \ - "Illegal context switch in RCU-sched"\ - " read-side critical section"); \ + "Illegal context switch in RCU-sched read-side critical section"); \ } while (0) #else /* #ifdef CONFIG_PROVE_RCU */ @@ -518,16 +516,14 @@ static inline void rcu_preempt_sleep_check(void) #define __rcu_dereference_check(p, c, space) \ ({ \ typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \ - rcu_lockdep_assert(c, "suspicious rcu_dereference_check()" \ - " usage"); \ + rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \ rcu_dereference_sparse(p, space); \ smp_read_barrier_depends(); \ ((typeof(*p) __force __kernel *)(_________p1)); \ }) #define __rcu_dereference_protected(p, c, space) \ ({ \ - rcu_lockdep_assert(c, "suspicious rcu_dereference_protected()" \ - " usage"); \ + rcu_lockdep_assert(c, "suspicious rcu_dereference_protected() usage"); \ rcu_dereference_sparse(p, space); \ ((typeof(*p) __force __kernel *)(p)); \ }) @@ -542,8 +538,7 @@ static inline void rcu_preempt_sleep_check(void) ({ \ typeof(p) _________p1 = ACCESS_ONCE(p); \ rcu_lockdep_assert(c, \ - "suspicious rcu_dereference_index_check()" \ - " usage"); \ + "suspicious rcu_dereference_index_check() usage"); \ smp_read_barrier_depends(); \ (_________p1); \ }) -- cgit v1.2.3 From 0adab9b9aa18d7e90337d43567f1eec3d5401b81 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Thu, 5 Dec 2013 16:19:15 -0800 Subject: rcu: Indentation and spacing fixes. This commit outdents expression-statement macros, thus repairing a few line-length complaints. Also fix some spacing errors called out by checkpatch.pl. Signed-off-by: Joe Perches Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rculist.h | 17 +++++++------- include/linux/rcupdate.h | 58 ++++++++++++++++++++++++------------------------ 2 files changed, 38 insertions(+), 37 deletions(-) (limited to 'include') diff --git a/include/linux/rculist.h b/include/linux/rculist.h index dbaf99084112..8183b46fbaa2 100644 --- a/include/linux/rculist.h +++ b/include/linux/rculist.h @@ -247,9 +247,10 @@ static inline void list_splice_init_rcu(struct list_head *list, * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). */ #define list_entry_rcu(ptr, type, member) \ - ({typeof (*ptr) __rcu *__ptr = (typeof (*ptr) __rcu __force *)ptr; \ - container_of((typeof(ptr))rcu_dereference_raw(__ptr), type, member); \ - }) +({ \ + typeof(*ptr) __rcu *__ptr = (typeof(*ptr) __rcu __force *)ptr; \ + container_of((typeof(ptr))rcu_dereference_raw(__ptr), type, member); \ +}) /** * Where are list_empty_rcu() and list_first_entry_rcu()? @@ -285,11 +286,11 @@ static inline void list_splice_init_rcu(struct list_head *list, * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). */ #define list_first_or_null_rcu(ptr, type, member) \ - ({struct list_head *__ptr = (ptr); \ - struct list_head *__next = ACCESS_ONCE(__ptr->next); \ - likely(__ptr != __next) ? \ - list_entry_rcu(__next, type, member) : NULL; \ - }) +({ \ + struct list_head *__ptr = (ptr); \ + struct list_head *__next = ACCESS_ONCE(__ptr->next); \ + likely(__ptr != __next) ? list_entry_rcu(__next, type, member) : NULL; \ +}) /** * list_for_each_entry_rcu - iterate over rcu list of given type diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index d946d3660633..278a9da69ec4 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -508,40 +508,40 @@ static inline void rcu_preempt_sleep_check(void) #endif /* #else #ifdef __CHECKER__ */ #define __rcu_access_pointer(p, space) \ - ({ \ - typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \ - rcu_dereference_sparse(p, space); \ - ((typeof(*p) __force __kernel *)(_________p1)); \ - }) +({ \ + typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \ + rcu_dereference_sparse(p, space); \ + ((typeof(*p) __force __kernel *)(_________p1)); \ +}) #define __rcu_dereference_check(p, c, space) \ - ({ \ - typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \ - rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \ - rcu_dereference_sparse(p, space); \ - smp_read_barrier_depends(); \ - ((typeof(*p) __force __kernel *)(_________p1)); \ - }) +({ \ + typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \ + rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \ + rcu_dereference_sparse(p, space); \ + smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ + ((typeof(*p) __force __kernel *)(_________p1)); \ +}) #define __rcu_dereference_protected(p, c, space) \ - ({ \ - rcu_lockdep_assert(c, "suspicious rcu_dereference_protected() usage"); \ - rcu_dereference_sparse(p, space); \ - ((typeof(*p) __force __kernel *)(p)); \ - }) +({ \ + rcu_lockdep_assert(c, "suspicious rcu_dereference_protected() usage"); \ + rcu_dereference_sparse(p, space); \ + ((typeof(*p) __force __kernel *)(p)); \ +}) #define __rcu_access_index(p, space) \ - ({ \ - typeof(p) _________p1 = ACCESS_ONCE(p); \ - rcu_dereference_sparse(p, space); \ - (_________p1); \ - }) +({ \ + typeof(p) _________p1 = ACCESS_ONCE(p); \ + rcu_dereference_sparse(p, space); \ + (_________p1); \ +}) #define __rcu_dereference_index_check(p, c) \ - ({ \ - typeof(p) _________p1 = ACCESS_ONCE(p); \ - rcu_lockdep_assert(c, \ - "suspicious rcu_dereference_index_check() usage"); \ - smp_read_barrier_depends(); \ - (_________p1); \ - }) +({ \ + typeof(p) _________p1 = ACCESS_ONCE(p); \ + rcu_lockdep_assert(c, \ + "suspicious rcu_dereference_index_check() usage"); \ + smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ + (_________p1); \ +}) /** * RCU_INITIALIZER() - statically initialize an RCU-protected global variable -- cgit v1.2.3 From 88c1863066ccfa456797e12c5d8b4631aa1ad0d0 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 16 Dec 2013 13:24:32 -0800 Subject: rcu: Define rcu_assign_pointer() in terms of smp_store_release() The new smp_store_release() function provides better guarantees than did rcu_assign_pointer(), and potentially less overhead on some architectures. The guarantee that smp_store_release() provides that rcu_assign_pointer() does that is obscure, but its lack could cause considerable confusion. This guarantee is illustrated by the following code fragment: struct foo { int a; int b; int c; struct foo *next; }; struct foo foo1; struct foo foo2; struct foo __rcu *foop; ... foo2.a = 1; foo2.b = 2; BUG_ON(foo2.c); rcu_assign_pointer(foop, &foo); ... fp = rcu_dereference(foop); fp.c = 3; The current rcu_assign_pointer() semantics permit the BUG_ON() to trigger because rcu_assign_pointer()'s smp_wmb() is not guaranteed to order prior reads against later writes. This commit therefore upgrades rcu_assign_pointer() from smp_wmb() to smp_store_release() to avoid this counter-intuitive outcome. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rcupdate.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 278a9da69ec4..32decf1a9c6c 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -44,6 +44,7 @@ #include #include #include +#include #ifdef CONFIG_RCU_TORTURE_TEST extern int rcutorture_runnable; /* for sysctl */ @@ -580,12 +581,7 @@ static inline void rcu_preempt_sleep_check(void) * please be careful when making changes to rcu_assign_pointer() and the * other macros that it invokes. */ -#define rcu_assign_pointer(p, v) \ - do { \ - smp_wmb(); \ - ACCESS_ONCE(p) = RCU_INITIALIZER(v); \ - } while (0) - +#define rcu_assign_pointer(p, v) smp_store_release(&p, RCU_INITIALIZER(v)) /** * rcu_access_pointer() - fetch RCU pointer with no dereferencing -- cgit v1.2.3 From 2f33b512a5460578f6cf11d7b7867bed53157c7c Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Sun, 17 Nov 2013 18:25:48 -0800 Subject: rcu: Optimize rcu_is_nocb_cpu() for RCU_NOCB_CPU_ALL If CONFIG_RCU_NOCB_CPU_ALL=y, then rcu_is_nocb_cpu() will always return true, however, the current version nevertheless checks rcu_nocb_mask. This commit therefore creates a static inline implementation of rcu_is_nocb_cpu() that unconditionally returns true when CONFIG_RCU_NOCB_CPU_ALL=y. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rcupdate.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 72bf3a01a4ee..281c90f8989e 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -1015,11 +1015,13 @@ static inline notrace void rcu_read_unlock_sched_notrace(void) #define kfree_rcu(ptr, rcu_head) \ __kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head)) -#ifdef CONFIG_RCU_NOCB_CPU +#if defined(CONFIG_RCU_NOCB_CPU_ALL) +static inline bool rcu_is_nocb_cpu(int cpu) { return true; } +#elif defined(CONFIG_RCU_NOCB_CPU) bool rcu_is_nocb_cpu(int cpu); #else static inline bool rcu_is_nocb_cpu(int cpu) { return false; } -#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */ +#endif /* Only for use by adaptive-ticks code. */ -- cgit v1.2.3 From ffa83fb565fbc397cbafb4b71fd1cce276d4c3b6 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Sun, 17 Nov 2013 19:27:16 -0800 Subject: rcu: Optimize rcu_needs_cpu() for RCU_NOCB_CPU_ALL If CONFIG_RCU_NOCB_CPU_ALL=y, then rcu_needs_cpu() will always return false, however, the current version nevertheless checks for RCU callbacks. This commit therefore creates a static inline implementation of rcu_needs_cpu() that unconditionally returns false when CONFIG_RCU_NOCB_CPU_ALL=y. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rcupdate.h | 8 ++++++++ include/linux/rcutiny.h | 6 ------ include/linux/rcutree.h | 2 ++ 3 files changed, 10 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 281c90f8989e..5f7d5f410d50 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -1015,6 +1015,14 @@ static inline notrace void rcu_read_unlock_sched_notrace(void) #define kfree_rcu(ptr, rcu_head) \ __kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head)) +#if defined(CONFIG_TINY_RCU) || defined(CONFIG_RCU_NOCB_CPU_ALL) +static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies) +{ + *delta_jiffies = ULONG_MAX; + return 0; +} +#endif /* #if defined(CONFIG_TINY_RCU) || defined(CONFIG_RCU_NOCB_CPU_ALL) */ + #if defined(CONFIG_RCU_NOCB_CPU_ALL) static inline bool rcu_is_nocb_cpu(int cpu) { return true; } #elif defined(CONFIG_RCU_NOCB_CPU) diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index 6f01771b571c..9524903487d0 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -68,12 +68,6 @@ static inline void kfree_call_rcu(struct rcu_head *head, call_rcu(head, func); } -static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies) -{ - *delta_jiffies = ULONG_MAX; - return 0; -} - static inline void rcu_note_context_switch(int cpu) { rcu_sched_qs(cpu); diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index 72137ee8c603..81198c84e268 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -31,7 +31,9 @@ #define __LINUX_RCUTREE_H void rcu_note_context_switch(int cpu); +#ifndef CONFIG_RCU_NOCB_CPU_ALL int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies); +#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */ void rcu_cpu_stall_reset(void); /* -- cgit v1.2.3 From 51b1130eb5823ddb90a9ad07d243031d8cb7ecf2 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 27 Jan 2014 11:49:39 -0800 Subject: rcutorture: Abstract rcu_torture_random() Because rcu_torture_random() will be used by the locking equivalent to rcutorture, pull it out into its own module. This new module cannot be separately configured, instead, use the Kconfig "select" statement from the Kconfig options of tests depending on it. Suggested-by: Rusty Russell Signed-off-by: Paul E. McKenney --- include/linux/torture.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 include/linux/torture.h (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h new file mode 100644 index 000000000000..979e3e6b378a --- /dev/null +++ b/include/linux/torture.h @@ -0,0 +1,47 @@ +/* + * Common functions for in-kernel torture tests. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. + * + * Copyright IBM Corporation, 2014 + * + * Author: Paul E. McKenney + */ + +#ifndef __LINUX_TORTURE_H +#define __LINUX_TORTURE_H + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct torture_random_state { + unsigned long trs_state; + long trs_count; +}; + +#define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 } + +unsigned long torture_random(struct torture_random_state *trsp); + +#endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From 9e2502254132261e0ea8010692fd447b1cedf627 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 27 Jan 2014 16:27:00 -0800 Subject: rcutorture: Abstract torture_param() Create a torture_param() macro and apply it to rcutorture in order to save a few lines of code. This same macro may be applied to other torture frameworks. Signed-off-by: Paul E. McKenney --- include/linux/torture.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 979e3e6b378a..5aae880b6b4e 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -35,13 +35,18 @@ #include #include +/* Definitions for a non-string torture-test module parameter. */ +#define torture_param(type, name, init, msg) \ + static type name = init; \ + module_param(name, type, 0444); \ + MODULE_PARM_DESC(name, msg); + +/* Low-rider random number generator. */ struct torture_random_state { unsigned long trs_state; long trs_count; }; - #define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 } - unsigned long torture_random(struct torture_random_state *trsp); #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From c2884de38e01134ae040d55aa5644049d1bb850f Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 29 Jan 2014 07:30:50 -0800 Subject: rcutorture: Abstract TOROUT_STRING() and friends These diagnostic macros are not confined to torturing RCU, so this commit makes them available to other torture tests. Also removed the do-while from TOROUT_STRING() in response to checkpatch complaints. Signed-off-by: Paul E. McKenney --- include/linux/torture.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 5aae880b6b4e..09be8887fb08 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -41,6 +41,14 @@ module_param(name, type, 0444); \ MODULE_PARM_DESC(name, msg); +#define TORTURE_FLAG "-torture:" +#define TOROUT_STRING(s) \ + pr_alert("%s" TORTURE_FLAG s "\n", torture_type) +#define VERBOSE_TOROUT_STRING(s) \ + do { if (verbose) pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0) +#define VERBOSE_TOROUT_ERRSTRING(s) \ + do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) + /* Low-rider random number generator. */ struct torture_random_state { unsigned long trs_state; -- cgit v1.2.3 From f67a33561e6e5463b548219df98130da95f2e4a7 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 29 Jan 2014 07:40:27 -0800 Subject: rcutorture: Abstract torture_shutdown_absorb() Because handling races between rmmod and normal shutdown is not specific to rcutorture, this commit renames rcutorture_shutdown_absorb() to torture_shutdown_absorb() and pulls it out into then kernel/torture.c module. This implies pulling the fullstop mechanism into kernel/torture.c as well. The exporting of fullstop and fullstop_mutex is ugly and must die. And it does in fact die in later commits that introduce higher-level APIs that encapsulate both of these variables. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett ` --- include/linux/torture.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 09be8887fb08..8474d776c864 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -41,6 +41,18 @@ module_param(name, type, 0444); \ MODULE_PARM_DESC(name, msg); +/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ +#define FULLSTOP_DONTSTOP 0 /* Normal operation. */ +#define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ +#define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ +extern int fullstop; +/* Protect fullstop transitions and spawning of kthreads. */ +extern struct mutex fullstop_mutex; + +/* Common module parameters. */ +extern char *torture_type; +extern bool verbose; + #define TORTURE_FLAG "-torture:" #define TOROUT_STRING(s) \ pr_alert("%s" TORTURE_FLAG s "\n", torture_type) @@ -57,4 +69,7 @@ struct torture_random_state { #define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 } unsigned long torture_random(struct torture_random_state *trsp); +/* Shutdown task absorption, for when the tasks cannot safely be killed. */ +void torture_shutdown_absorb(const char *title); + #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From 3808dc9fab05913060626d7f0edd0f195cb9dcab Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 28 Jan 2014 15:29:21 -0800 Subject: rcutorture: Abstract torture_shuffle() The torture_shuffle() function forces each CPU in turn to go idle periodically in order to check for problems interacting with per-CPU variables and with dyntick-idle mode. Because this sort of debugging is not specific to RCU, this commit abstracts that functionality. This in turn requires abstracting some additional infrastructure. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 8474d776c864..544a2c33c1ae 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -69,6 +69,11 @@ struct torture_random_state { #define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 } unsigned long torture_random(struct torture_random_state *trsp); +/* Task shuffler, which causes CPUs to occasionally go idle. */ +void torture_shuffle_task_register(struct task_struct *tp); +int torture_shuffle_init(long shuffint); +void torture_shuffle_cleanup(void); + /* Shutdown task absorption, for when the tasks cannot safely be killed. */ void torture_shutdown_absorb(const char *title); -- cgit v1.2.3 From 2e9e8081d2e7a4efb582a240aa7fee991bbbabb0 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 28 Jan 2014 15:58:22 -0800 Subject: rcutorture: Abstract torture_onoff() Because online/offline torturing is not specific to RCU, this commit abstracts it into the kernel/torture.c module to allow other torture tests to use it. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 544a2c33c1ae..be3694a702e9 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -61,6 +61,18 @@ extern bool verbose; #define VERBOSE_TOROUT_ERRSTRING(s) \ do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) +/* Definitions for a non-string torture-test module parameter. */ +#define torture_parm(type, name, init, msg) \ + static type name = init; \ + module_param(name, type, 0444); \ + MODULE_PARM_DESC(name, msg); + +/* Definitions for online/offline exerciser. */ +int torture_onoff_init(long ooholdoff, long oointerval); +void torture_onoff_cleanup(void); +char *torture_onoff_stats(char *page); +bool torture_onoff_failures(void); + /* Low-rider random number generator. */ struct torture_random_state { unsigned long trs_state; -- cgit v1.2.3 From b5daa8f3b3b2b0133ad40e13d4f722070119ce36 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 30 Jan 2014 13:38:09 -0800 Subject: rcutorture: Abstract torture-test initialization This commit creates torture_init_begin() and torture_init_end() functions to abstract locking and allow the torture_type and verbose variables in kernel/torture.o to become static. With a bit more abstraction, fullstop_mutex will also become static. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index be3694a702e9..428d2712be04 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -49,10 +49,6 @@ extern int fullstop; /* Protect fullstop transitions and spawning of kthreads. */ extern struct mutex fullstop_mutex; -/* Common module parameters. */ -extern char *torture_type; -extern bool verbose; - #define TORTURE_FLAG "-torture:" #define TOROUT_STRING(s) \ pr_alert("%s" TORTURE_FLAG s "\n", torture_type) @@ -89,4 +85,9 @@ void torture_shuffle_cleanup(void); /* Shutdown task absorption, for when the tasks cannot safely be killed. */ void torture_shutdown_absorb(const char *title); +/* Initialization and cleanup. */ + +void torture_init_begin(char *ttype, bool v); +void torture_init_end(void); + #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From cc47ae0830264f07442070b36fe0d0a4d4e3c313 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 30 Jan 2014 14:21:11 -0800 Subject: rcutorture: Abstract torture-test cleanup This commit creates a torture_cleanup() that handles the generic cleanup actions local to kernel/torture.c. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 428d2712be04..31d69930e5cf 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -65,7 +65,6 @@ extern struct mutex fullstop_mutex; /* Definitions for online/offline exerciser. */ int torture_onoff_init(long ooholdoff, long oointerval); -void torture_onoff_cleanup(void); char *torture_onoff_stats(char *page); bool torture_onoff_failures(void); @@ -80,14 +79,13 @@ unsigned long torture_random(struct torture_random_state *trsp); /* Task shuffler, which causes CPUs to occasionally go idle. */ void torture_shuffle_task_register(struct task_struct *tp); int torture_shuffle_init(long shuffint); -void torture_shuffle_cleanup(void); /* Shutdown task absorption, for when the tasks cannot safely be killed. */ void torture_shutdown_absorb(const char *title); /* Initialization and cleanup. */ - void torture_init_begin(char *ttype, bool v); void torture_init_end(void); +bool torture_cleanup(void); #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From 4622b487ecf0094401ac10e504606e5cbdea5a6e Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 30 Jan 2014 15:37:19 -0800 Subject: rcutorture: Abstract torture_shutdown_notify() Because handling the race between rmmod and system shutdown is not specific to RCU, this commit abstracts torture_shutdown_notify(), placing this code into kernel/torture.c. This change also allows fullstop_mutex to be private to kernel/torture.c. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 31d69930e5cf..742d8a402f19 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -46,8 +46,6 @@ #define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ #define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ extern int fullstop; -/* Protect fullstop transitions and spawning of kthreads. */ -extern struct mutex fullstop_mutex; #define TORTURE_FLAG "-torture:" #define TOROUT_STRING(s) \ -- cgit v1.2.3 From 36970bb91d89618d3495babf44b934e9c9db6bbc Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 30 Jan 2014 15:49:29 -0800 Subject: rcutorture: Privatize fullstop This commit introduces the torture_must_stop() function in order to keep use of the fullstop variable local to kernel/torture.c. There is also a torture_must_stop_irq() counterpart for use from RCU callbacks, timeout handlers, and the like. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 742d8a402f19..0259db38bfb0 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -41,12 +41,6 @@ module_param(name, type, 0444); \ MODULE_PARM_DESC(name, msg); -/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ -#define FULLSTOP_DONTSTOP 0 /* Normal operation. */ -#define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ -#define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ -extern int fullstop; - #define TORTURE_FLAG "-torture:" #define TOROUT_STRING(s) \ pr_alert("%s" TORTURE_FLAG s "\n", torture_type) @@ -85,5 +79,7 @@ void torture_shutdown_absorb(const char *title); void torture_init_begin(char *ttype, bool v); void torture_init_end(void); bool torture_cleanup(void); +bool torture_must_stop(void); +bool torture_must_stop_irq(void); #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From 628edaa5062282b6e3d76c886fd2cbccae5cb87b Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 31 Jan 2014 11:57:43 -0800 Subject: rcutorture: Abstract stutter_wait() Because stuttering the test load (stopping and restarting it) is useful for non-RCU testing, this commit moves the load-stuttering functionality to kernel/torture.c. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 0259db38bfb0..203f127d9ddf 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -75,8 +75,13 @@ int torture_shuffle_init(long shuffint); /* Shutdown task absorption, for when the tasks cannot safely be killed. */ void torture_shutdown_absorb(const char *title); +/* Task stuttering, which forces load/no-load transitions. */ +void stutter_wait(const char *title); +int torture_stutter_init(int s); +void torture_stutter_cleanup(void); + /* Initialization and cleanup. */ -void torture_init_begin(char *ttype, bool v); +void torture_init_begin(char *ttype, bool v, int *runnable); void torture_init_end(void); bool torture_cleanup(void); bool torture_must_stop(void); -- cgit v1.2.3 From e991dbc0770b01b7dc7d6d7660442e83ebd11828 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 31 Jan 2014 14:52:13 -0800 Subject: rcutorture: Abstract torture_shutdown() Because auto-shutdown of torture testing is not specific to RCU, this commit moves the auto-shutdown function to kernel/torture.c. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 203f127d9ddf..c79c41d543ef 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -72,8 +72,10 @@ unsigned long torture_random(struct torture_random_state *trsp); void torture_shuffle_task_register(struct task_struct *tp); int torture_shuffle_init(long shuffint); -/* Shutdown task absorption, for when the tasks cannot safely be killed. */ +/* Test auto-shutdown handling. */ void torture_shutdown_absorb(const char *title); +int torture_shutdown_init(int ssecs, void (*cleanup)(void)); +void torture_shutdown_cleanup(void); /* Task stuttering, which forces load/no-load transitions. */ void stutter_wait(const char *title); -- cgit v1.2.3 From 7fafaac5b9ce22cc57777865390520476ad2262d Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 31 Jan 2014 17:37:28 -0800 Subject: rcutorture: Fix rcutorture shutdown races Not all of the rcutorture kthreads waited for kthread_should_stop() before returning from their top-level functions, and none of them used torture_shutdown_absorb() properly. These problems can result in segfaults and hangs at shutdown time, and some recent changes perturbed timing sufficiently to make them much more probable. This commit therefore creates a torture_kthread_stopping() function that does the proper kthread shutdown dance in one centralized location. Accommodate this grouping by making VERBOSE_TOROUT_STRING() capable of taking a non-const string as its argument, which allows the new torture_kthread_stopping() to pass its "title" argument directly to the updated version of VERBOSE_TOROUT_STRING(). Signed-off-by: Paul E. McKenney --- include/linux/torture.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index c79c41d543ef..2ea11094daf6 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -45,7 +45,7 @@ #define TOROUT_STRING(s) \ pr_alert("%s" TORTURE_FLAG s "\n", torture_type) #define VERBOSE_TOROUT_STRING(s) \ - do { if (verbose) pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0) + do { if (verbose) pr_alert("%s" TORTURE_FLAG " %s\n", torture_type, s); } while (0) #define VERBOSE_TOROUT_ERRSTRING(s) \ do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) @@ -88,5 +88,6 @@ void torture_init_end(void); bool torture_cleanup(void); bool torture_must_stop(void); bool torture_must_stop_irq(void); +void torture_kthread_stopping(char *title); #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From 47cf29b9e721967aac95ebda9e50408219755852 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 3 Feb 2014 11:52:27 -0800 Subject: rcutorture: Abstract torture_create_kthread() Creation of kthreads is not RCU-specific, so this commit abstracts out torture_create_kthread(), saving a few tens of lines of code in the process. This change requires modifying VERBOSE_TOROUT_ERRSTRING() to take a non-const string, so that _torture_create_kthread() can avoid an open-coded substitute. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 2ea11094daf6..430cc3008628 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -47,7 +47,7 @@ #define VERBOSE_TOROUT_STRING(s) \ do { if (verbose) pr_alert("%s" TORTURE_FLAG " %s\n", torture_type, s); } while (0) #define VERBOSE_TOROUT_ERRSTRING(s) \ - do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) + do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! %s\n", torture_type, s); } while (0) /* Definitions for a non-string torture-test module parameter. */ #define torture_parm(type, name, init, msg) \ @@ -89,5 +89,11 @@ bool torture_cleanup(void); bool torture_must_stop(void); bool torture_must_stop_irq(void); void torture_kthread_stopping(char *title); +int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m, + char *f, struct task_struct **tp); + +#define torture_create_kthread(n, arg, tp) \ + _torture_create_kthread(n, (arg), #n, "Creating " #n " task", \ + "Failed to create " #n, &(tp)) #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From 9c029b86098decd4660eec511b8d2d42da3e7dd9 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 4 Feb 2014 11:47:08 -0800 Subject: rcutorture: Abstract torture_stop_kthread() Stopping of kthreads is not RCU-specific, so this commit abstracts out torture_stop_kthread(), saving a few lines of code in the process. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 430cc3008628..7ccfb0a16728 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -91,9 +91,12 @@ bool torture_must_stop_irq(void); void torture_kthread_stopping(char *title); int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m, char *f, struct task_struct **tp); +void _torture_stop_kthread(char *m, struct task_struct **tp); #define torture_create_kthread(n, arg, tp) \ _torture_create_kthread(n, (arg), #n, "Creating " #n " task", \ "Failed to create " #n, &(tp)) +#define torture_stop_kthread(n, tp) \ + _torture_stop_kthread("Stopping " #n " task", &(tp)) #endif /* __LINUX_TORTURE_H */ -- cgit v1.2.3 From bfefc73aa1d1bad317bccef8a15da39263d3d962 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 4 Feb 2014 12:35:27 -0800 Subject: rcutorture: Stop generic kthreads in torture_cleanup() The specific torture modules (like rcutorture) need to call torture_cleanup() in any case, so this commit makes torture_cleanup() deal with torture_shutdown_cleanup() and torture_stutter_cleanup() so that the specific modules don't have to deal with these details. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/torture.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include') diff --git a/include/linux/torture.h b/include/linux/torture.h index 7ccfb0a16728..b2e2b468e511 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -75,12 +75,10 @@ int torture_shuffle_init(long shuffint); /* Test auto-shutdown handling. */ void torture_shutdown_absorb(const char *title); int torture_shutdown_init(int ssecs, void (*cleanup)(void)); -void torture_shutdown_cleanup(void); /* Task stuttering, which forces load/no-load transitions. */ void stutter_wait(const char *title); int torture_stutter_init(int s); -void torture_stutter_cleanup(void); /* Initialization and cleanup. */ void torture_init_begin(char *ttype, bool v, int *runnable); -- cgit v1.2.3 From 7a754743185a4b05818e10058fa2fbe4e6969085 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Tue, 11 Feb 2014 16:10:12 -0500 Subject: rcu: Fix sparse warning for rcu_expedited from kernel/ksysfs.c This commit fixes the follwoing warning: kernel/ksysfs.c:143:5: warning: symbol 'rcu_expedited' was not declared. Should it be static? Signed-off-by: Paul Gortmaker [ paulmck: Moved the declaration to include/linux/rcupdate.h to avoid including the RCU-internal rcu.h file outside of RCU. ] Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- include/linux/rcupdate.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 32decf1a9c6c..f3706c6b2e21 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -46,6 +46,7 @@ #include #include +extern int rcu_expedited; /* for sysctl */ #ifdef CONFIG_RCU_TORTURE_TEST extern int rcutorture_runnable; /* for sysctl */ #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */ -- cgit v1.2.3 From 765a3f4fed708ae429ee095914a7897acb3a65bd Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Mar 2014 16:37:08 -0700 Subject: rcu: Provide grace-period piggybacking API The following pattern is currently not well supported by RCU: 1. Make data element inaccessible to RCU readers. 2. Do work that probably lasts for more than one grace period. 3. Do something to make sure RCU readers in flight before #1 above have completed. Here are some things that could currently be done: a. Do a synchronize_rcu() unconditionally at either #1 or #3 above. This works, but imposes needless work and latency. b. Post an RCU callback at #1 above that does a wakeup, then wait for the wakeup at #3. This works well, but likely results in an extra unneeded grace period. Open-coding this is also a bit more semi-tricky code than would be good. This commit therefore adds get_state_synchronize_rcu() and cond_synchronize_rcu() APIs. Call get_state_synchronize_rcu() at #1 above and pass its return value to cond_synchronize_rcu() at #3 above. This results in a call to synchronize_rcu() if no grace period has elapsed between #1 and #3, but requires only a load, comparison, and memory barrier if a full grace period did elapse. Requested-by: Peter Zijlstra Signed-off-by: Paul E. McKenney Acked-by: Peter Zijlstra --- include/linux/rcutiny.h | 10 ++++++++++ include/linux/rcutree.h | 2 ++ 2 files changed, 12 insertions(+) (limited to 'include') diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index e8cb6e3b52a7..425c659d54e5 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -27,6 +27,16 @@ #include +static inline unsigned long get_state_synchronize_rcu(void) +{ + return 0; +} + +static inline void cond_synchronize_rcu(unsigned long oldstate) +{ + might_sleep(); +} + static inline void rcu_barrier_bh(void) { wait_rcu_gp(call_rcu_bh); diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index e9c63884df0a..a59ca05fd4e3 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -76,6 +76,8 @@ static inline void synchronize_rcu_bh_expedited(void) void rcu_barrier(void); void rcu_barrier_bh(void); void rcu_barrier_sched(void); +unsigned long get_state_synchronize_rcu(void); +void cond_synchronize_rcu(unsigned long oldstate); extern unsigned long rcutorture_testseq; extern unsigned long rcutorture_vernum; -- cgit v1.2.3