rcu: Move RCU-related source code to kernel/rcu directory

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>

15 files changed, 105 insertions, 62 deletions

diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index fe397f90a34f..6c9d9d37c83a 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -87,7 +87,10 @@ X!Iinclude/linux/kobject.h
 !Ekernel/printk/printk.c
 !Ekernel/panic.c
 !Ekernel/sys.c
-!Ekernel/rcupdate.c
+!Ekernel/rcu/srcu.c
+!Ekernel/rcu/tree.c
+!Ekernel/rcu/tree_plugin.h
+!Ekernel/rcu/update.c
      </sect1>
 
      <sect1><title>Device Resource Management</title>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 1a036cd972fb..c3dc13e90a40 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2595,7 +2595,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
         ramdisk_size=   [RAM] Sizes of RAM disks in kilobytes
                         See Documentation/blockdev/ramdisk.txt.
 
-        rcu_nocbs=      [KNL,BOOT]
+        rcu_nocbs=      [KNL]
                         In kernels built with CONFIG_RCU_NOCB_CPU=y, set
                         the specified list of CPUs to be no-callback CPUs.
                         Invocation of these CPUs' RCU callbacks will
@@ -2608,7 +2608,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         real-time workloads.  It can also improve energy
                         efficiency for asymmetric multiprocessors.
 
-        rcu_nocb_poll   [KNL,BOOT]
+        rcu_nocb_poll   [KNL]
                         Rather than requiring that offloaded CPUs
                         (specified by rcu_nocbs= above) explicitly
                         awaken the corresponding "rcuoN" kthreads,
@@ -2619,126 +2619,145 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         energy efficiency by requiring that the kthreads
                         periodically wake up to do the polling.
 
-        rcutree.blimit= [KNL,BOOT]
+        rcutree.blimit= [KNL]
                         Set maximum number of finished RCU callbacks to process
                         in one batch.
 
-        rcutree.fanout_leaf=    [KNL,BOOT]
+        rcutree.rcu_fanout_leaf= [KNL]
                         Increase the number of CPUs assigned to each
                         leaf rcu_node structure.  Useful for very large
                         systems.
 
-        rcutree.jiffies_till_first_fqs= [KNL,BOOT]
+        rcutree.jiffies_till_first_fqs= [KNL]
                         Set delay from grace-period initialization to
                         first attempt to force quiescent states.
                         Units are jiffies, minimum value is zero,
                         and maximum value is HZ.
 
-        rcutree.jiffies_till_next_fqs= [KNL,BOOT]
+        rcutree.jiffies_till_next_fqs= [KNL]
                         Set delay between subsequent attempts to force
                         quiescent states.  Units are jiffies, minimum
                         value is one, and maximum value is HZ.
 
-        rcutree.qhimark=        [KNL,BOOT]
+        rcutree.qhimark= [KNL]
                         Set threshold of queued
                         RCU callbacks over which batch limiting is disabled.
 
-        rcutree.qlowmark=       [KNL,BOOT]
+        rcutree.qlowmark= [KNL]
                         Set threshold of queued RCU callbacks below which
                         batch limiting is re-enabled.
 
-        rcutree.rcu_cpu_stall_suppress= [KNL,BOOT]
-                        Suppress RCU CPU stall warning messages.
-
-        rcutree.rcu_cpu_stall_timeout= [KNL,BOOT]
-                        Set timeout for RCU CPU stall warning messages.
-
-        rcutree.rcu_idle_gp_delay=      [KNL,BOOT]
+        rcutree.rcu_idle_gp_delay= [KNL]
                         Set wakeup interval for idle CPUs that have
                         RCU callbacks (RCU_FAST_NO_HZ=y).
 
-        rcutree.rcu_idle_lazy_gp_delay= [KNL,BOOT]
+        rcutree.rcu_idle_lazy_gp_delay= [KNL]
                         Set wakeup interval for idle CPUs that have
                         only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
                         Lazy RCU callbacks are those which RCU can
                         prove do nothing more than free memory.
 
-        rcutorture.fqs_duration= [KNL,BOOT]
+        rcutorture.fqs_duration= [KNL]
                         Set duration of force_quiescent_state bursts.
 
-        rcutorture.fqs_holdoff= [KNL,BOOT]
+        rcutorture.fqs_holdoff= [KNL]
                         Set holdoff time within force_quiescent_state bursts.
 
-        rcutorture.fqs_stutter= [KNL,BOOT]
+        rcutorture.fqs_stutter= [KNL]
                         Set wait time between force_quiescent_state bursts.
 
-        rcutorture.irqreader= [KNL,BOOT]
-                        Test RCU readers from irq handlers.
+        rcutorture.gp_exp= [KNL]
+                        Use expedited update-side primitives.
+
+        rcutorture.gp_normal= [KNL]
+                        Use normal (non-expedited) update-side primitives.
+                        If both gp_exp and gp_normal are set, do both.
+                        If neither gp_exp nor gp_normal are set, still
+                        do both.
 
-        rcutorture.n_barrier_cbs= [KNL,BOOT]
+        rcutorture.n_barrier_cbs= [KNL]
                         Set callbacks/threads for rcu_barrier() testing.
 
-        rcutorture.nfakewriters= [KNL,BOOT]
+        rcutorture.nfakewriters= [KNL]
                         Set number of concurrent RCU writers.  These just
                         stress RCU, they don't participate in the actual
                         test, hence the "fake".
 
-        rcutorture.nreaders= [KNL,BOOT]
+        rcutorture.nreaders= [KNL]
                         Set number of RCU readers.
 
-        rcutorture.onoff_holdoff= [KNL,BOOT]
+        rcutorture.object_debug= [KNL]
+                        Enable debug-object double-call_rcu() testing.
+
+        rcutorture.onoff_holdoff= [KNL]
                         Set time (s) after boot for CPU-hotplug testing.
 
-        rcutorture.onoff_interval= [KNL,BOOT]
+        rcutorture.onoff_interval= [KNL]
                         Set time (s) between CPU-hotplug operations, or
                         zero to disable CPU-hotplug testing.
 
-        rcutorture.shuffle_interval= [KNL,BOOT]
+        rcutorture.rcutorture_runnable= [BOOT]
+                        Start rcutorture running at boot time.
+
+        rcutorture.shuffle_interval= [KNL]
                         Set task-shuffle interval (s).  Shuffling tasks
                         allows some CPUs to go into dyntick-idle mode
                         during the rcutorture test.
 
-        rcutorture.shutdown_secs= [KNL,BOOT]
+        rcutorture.shutdown_secs= [KNL]
                         Set time (s) after boot system shutdown.  This
                         is useful for hands-off automated testing.
 
-        rcutorture.stall_cpu= [KNL,BOOT]
+        rcutorture.stall_cpu= [KNL]
                         Duration of CPU stall (s) to test RCU CPU stall
                         warnings, zero to disable.
 
-        rcutorture.stall_cpu_holdoff= [KNL,BOOT]
+        rcutorture.stall_cpu_holdoff= [KNL]
                         Time to wait (s) after boot before inducing stall.
 
-        rcutorture.stat_interval= [KNL,BOOT]
+        rcutorture.stat_interval= [KNL]
                         Time (s) between statistics printk()s.
 
-        rcutorture.stutter= [KNL,BOOT]
+        rcutorture.stutter= [KNL]
                         Time (s) to stutter testing, for example, specifying
                         five seconds causes the test to run for five seconds,
                         wait for five seconds, and so on.  This tests RCU's
                         ability to transition abruptly to and from idle.
 
-        rcutorture.test_boost= [KNL,BOOT]
+        rcutorture.test_boost= [KNL]
                         Test RCU priority boosting?  0=no, 1=maybe, 2=yes.
                         "Maybe" means test if the RCU implementation
                         under test support RCU priority boosting.
 
-        rcutorture.test_boost_duration= [KNL,BOOT]
+        rcutorture.test_boost_duration= [KNL]
                         Duration (s) of each individual boost test.
 
-        rcutorture.test_boost_interval= [KNL,BOOT]
+        rcutorture.test_boost_interval= [KNL]
                         Interval (s) between each boost test.
 
-        rcutorture.test_no_idle_hz= [KNL,BOOT]
+        rcutorture.test_no_idle_hz= [KNL]
                         Test RCU's dyntick-idle handling.  See also the
                         rcutorture.shuffle_interval parameter.
 
-        rcutorture.torture_type= [KNL,BOOT]
+        rcutorture.torture_type= [KNL]
                         Specify the RCU implementation to test.
 
-        rcutorture.verbose= [KNL,BOOT]
+        rcutorture.verbose= [KNL]
                         Enable additional printk() statements.
 
+        rcupdate.rcu_expedited= [KNL]
+                        Use expedited grace-period primitives, for
+                        example, synchronize_rcu_expedited() instead
+                        of synchronize_rcu().  This reduces latency,
+                        but can increase CPU utilization, degrade
+                        real-time latency, and degrade energy efficiency.
+
+        rcupdate.rcu_cpu_stall_suppress= [KNL]
+                        Suppress RCU CPU stall warning messages.
+
+        rcupdate.rcu_cpu_stall_timeout= [KNL]
+                        Set timeout for RCU CPU stall warning messages.
+
         rdinit=         [KNL]
                         Format: <full_path>
                         Run specified binary instead of /init from the ramdisk,
diff --git a/MAINTAINERS b/MAINTAINERS
index e61c2e83fc2b..28f2478b6794 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6903,7 +6903,7 @@ M:	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
 S:      Supported
 T:      git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
 F:      Documentation/RCU/torture.txt
-F:      kernel/rcutorture.c
+F:      kernel/rcu/torture.c
 
 RDC R-321X SoC
 M:      Florian Fainelli <florian@openwrt.org>
@@ -6930,8 +6930,9 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
 F:      Documentation/RCU/
 X:      Documentation/RCU/torture.txt
 F:      include/linux/rcu*
-F:      kernel/rcu*
-X:      kernel/rcutorture.c
+X:      include/linux/srcu.h
+F:      kernel/rcu/
+X:      kernel/rcu/torture.c
 
 REAL TIME CLOCK (RTC) SUBSYSTEM
 M:      Alessandro Zummo <a.zummo@towertech.it>
@@ -7618,8 +7619,8 @@ M:	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
 W:      http://www.rdrop.com/users/paulmck/RCU/
 S:      Supported
 T:      git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
-F:      include/linux/srcu*
-F:      kernel/srcu*
+F:      include/linux/srcu.h
+F:      kernel/rcu/srcu.c
 
 SMACK SECURITY MODULE
 M:      Casey Schaufler <casey@schaufler-ca.com>
diff --git a/kernel/Makefile b/kernel/Makefile
index 1ce47553fb02..f99d908b5550 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -6,9 +6,9 @@ obj-y     = fork.o exec_domain.o panic.o \
             cpu.o exit.o itimer.o time.o softirq.o resource.o \
             sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \
             signal.o sys.o kmod.o workqueue.o pid.o task_work.o \
-            rcupdate.o extable.o params.o posix-timers.o \
+            extable.o params.o posix-timers.o \
             kthread.o wait.o sys_ni.o posix-cpu-timers.o mutex.o \
-            hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
+            hrtimer.o rwsem.o nsproxy.o semaphore.o \
             notifier.o ksysfs.o cred.o reboot.o \
             async.o range.o groups.o lglock.o smpboot.o
 
@@ -27,6 +27,7 @@ obj-y += power/
 obj-y += printk/
 obj-y += cpu/
 obj-y += irq/
+obj-y += rcu/
 
 obj-$(CONFIG_CHECKPOINT_RESTORE) += kcmp.o
 obj-$(CONFIG_FREEZER) += freezer.o
@@ -81,12 +82,6 @@ obj-$(CONFIG_KGDB) += debug/
 obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
 obj-$(CONFIG_LOCKUP_DETECTOR) += watchdog.o
 obj-$(CONFIG_SECCOMP) += seccomp.o
-obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
-obj-$(CONFIG_TREE_RCU) += rcutree.o
-obj-$(CONFIG_TREE_PREEMPT_RCU) += rcutree.o
-obj-$(CONFIG_TREE_RCU_TRACE) += rcutree_trace.o
-obj-$(CONFIG_TINY_RCU) += rcutiny.o
-obj-$(CONFIG_TINY_PREEMPT_RCU) += rcutiny.o
 obj-$(CONFIG_RELAY) += relay.o
 obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
 obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
diff --git a/kernel/rcu/Makefile b/kernel/rcu/Makefile
new file mode 100644
index 000000000000..01e9ec37a3e3
--- /dev/null
+++ b/kernel/rcu/Makefile
@@ -0,0 +1,6 @@
+obj-y += update.o srcu.o
+obj-$(CONFIG_RCU_TORTURE_TEST) += torture.o
+obj-$(CONFIG_TREE_RCU) += tree.o
+obj-$(CONFIG_TREE_PREEMPT_RCU) += tree.o
+obj-$(CONFIG_TREE_RCU_TRACE) += tree_trace.o
+obj-$(CONFIG_TINY_RCU) += tiny.o
diff --git a/kernel/rcu.h b/kernel/rcu/rcu.h
index 7859a0a3951e..7859a0a3951e 100644
--- a/kernel/rcu.h
+++ b/kernel/rcu/rcu.h
diff --git a/kernel/srcu.c b/kernel/rcu/srcu.c
index 01d5ccb8bfe3..01d5ccb8bfe3 100644
--- a/kernel/srcu.c
+++ b/kernel/rcu/srcu.c
diff --git a/kernel/rcutiny.c b/kernel/rcu/tiny.c
index 312e9709713f..0c9a934cfec1 100644
--- a/kernel/rcutiny.c
+++ b/kernel/rcu/tiny.c
@@ -43,7 +43,7 @@
 
 #include "rcu.h"
 
-/* Forward declarations for rcutiny_plugin.h. */
+/* Forward declarations for tiny_plugin.h. */
 struct rcu_ctrlblk;
 static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp);
 static void rcu_process_callbacks(struct softirq_action *unused);
@@ -53,7 +53,7 @@ static void __call_rcu(struct rcu_head *head,
 
 static long long rcu_dynticks_nesting = DYNTICK_TASK_EXIT_IDLE;
 
-#include "rcutiny_plugin.h"
+#include "tiny_plugin.h"
 
 /* Common code for rcu_idle_enter() and rcu_irq_exit(), see kernel/rcutree.c. */
 static void rcu_idle_enter_common(long long newval)
@@ -67,7 +67,7 @@ static void rcu_idle_enter_common(long long newval)
         RCU_TRACE(trace_rcu_dyntick(TPS("Start"),
                                     rcu_dynticks_nesting, newval));
         if (!is_idle_task(current)) {
-                struct task_struct *idle = idle_task(smp_processor_id());
+                struct task_struct *idle __maybe_unused = idle_task(smp_processor_id());
 
                 RCU_TRACE(trace_rcu_dyntick(TPS("Entry error: not idle task"),
                                             rcu_dynticks_nesting, newval));
@@ -128,7 +128,7 @@ static void rcu_idle_exit_common(long long oldval)
         }
         RCU_TRACE(trace_rcu_dyntick(TPS("End"), oldval, rcu_dynticks_nesting));
         if (!is_idle_task(current)) {
-                struct task_struct *idle = idle_task(smp_processor_id());
+                struct task_struct *idle __maybe_unused = idle_task(smp_processor_id());
 
                 RCU_TRACE(trace_rcu_dyntick(TPS("Exit error: not idle task"),
                           oldval, rcu_dynticks_nesting));
diff --git a/kernel/rcutiny_plugin.h b/kernel/rcu/tiny_plugin.h
index 280d06cae352..280d06cae352 100644
--- a/kernel/rcutiny_plugin.h
+++ b/kernel/rcu/tiny_plugin.h
diff --git a/kernel/rcutorture.c b/kernel/rcu/torture.c
index be63101c6175..3929cd451511 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcu/torture.c
@@ -52,6 +52,12 @@
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>");
 
+MODULE_ALIAS("rcutorture");
+#ifdef MODULE_PARAM_PREFIX
+#undef MODULE_PARAM_PREFIX
+#endif
+#define MODULE_PARAM_PREFIX "rcutorture."
+
 static int fqs_duration;
 module_param(fqs_duration, int, 0444);
 MODULE_PARM_DESC(fqs_duration, "Duration of fqs bursts (us), 0 to disable");
diff --git a/kernel/rcutree.c b/kernel/rcu/tree.c
index 240604aa3f70..8a2c81e86dda 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcu/tree.c
@@ -41,6 +41,7 @@
 #include <linux/export.h>
 #include <linux/completion.h>
 #include <linux/moduleparam.h>
+#include <linux/module.h>
 #include <linux/percpu.h>
 #include <linux/notifier.h>
 #include <linux/cpu.h>
@@ -56,11 +57,17 @@
 #include <linux/ftrace_event.h>
 #include <linux/suspend.h>
 
-#include "rcutree.h"
+#include "tree.h"
 #include <trace/events/rcu.h>
 
 #include "rcu.h"
 
+MODULE_ALIAS("rcutree");
+#ifdef MODULE_PARAM_PREFIX
+#undef MODULE_PARAM_PREFIX
+#endif
+#define MODULE_PARAM_PREFIX "rcutree."
+
 /* Data structures. */
 
 static struct lock_class_key rcu_node_class[RCU_NUM_LVLS];
@@ -3298,7 +3305,7 @@ static void __init rcu_init_one(struct rcu_state *rsp,
 
 /*
  * Compute the rcu_node tree geometry from kernel parameters.  This cannot
- * replace the definitions in rcutree.h because those are needed to size
+ * replace the definitions in tree.h because those are needed to size
  * the ->node array in the rcu_state structure.
  */
 static void __init rcu_init_geometry(void)
@@ -3393,4 +3400,4 @@ void __init rcu_init(void)
                 rcu_cpu_notify(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
 }
 
-#include "rcutree_plugin.h"
+#include "tree_plugin.h"
diff --git a/kernel/rcutree.h b/kernel/rcu/tree.h
index 52be957c9fe2..52be957c9fe2 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcu/tree.h
diff --git a/kernel/rcutree_plugin.h b/kernel/rcu/tree_plugin.h
index 8d85a5ce093a..3822ac0c4b27 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -28,7 +28,7 @@
 #include <linux/gfp.h>
 #include <linux/oom.h>
 #include <linux/smpboot.h>
-#include "time/tick-internal.h"
+#include "../time/tick-internal.h"
 
 #define RCU_KTHREAD_PRIO 1
 
@@ -1133,7 +1133,7 @@ void exit_rcu(void)
 
 #ifdef CONFIG_RCU_BOOST
 
-#include "rtmutex_common.h"
+#include "../rtmutex_common.h"
 
 #ifdef CONFIG_RCU_TRACE
 
diff --git a/kernel/rcutree_trace.c b/kernel/rcu/tree_trace.c
index cf6c17412932..3596797b7e46 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -44,7 +44,7 @@
 #include <linux/seq_file.h>
 
 #define RCU_TREE_NONCORE
-#include "rcutree.h"
+#include "tree.h"
 
 static int r_open(struct inode *inode, struct file *file,
                                         const struct seq_operations *op)
diff --git a/kernel/rcupdate.c b/kernel/rcu/update.c
index c07af1c4e1bb..6cb3dff89e2b 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcu/update.c
@@ -53,6 +53,12 @@
 
 #include "rcu.h"
 
+MODULE_ALIAS("rcupdate");
+#ifdef MODULE_PARAM_PREFIX
+#undef MODULE_PARAM_PREFIX
+#endif
+#define MODULE_PARAM_PREFIX "rcupdate."
+
 module_param(rcu_expedited, int, 0);
 
 #ifdef CONFIG_PREEMPT_RCU