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-rw-r--r--init/Kconfig64
-rw-r--r--init/Makefile4
-rw-r--r--init/do_mounts.c2
-rw-r--r--init/init_task.c24
-rw-r--r--init/main.c57
5 files changed, 108 insertions, 43 deletions
diff --git a/init/Kconfig b/init/Kconfig
index 92a1296ba9fa..a30fe085940e 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -461,6 +461,33 @@ config RCU_FANOUT
Select a specific number if testing RCU itself.
Take the default if unsure.
+config RCU_FANOUT_LEAF
+ int "Tree-based hierarchical RCU leaf-level fanout value"
+ range 2 RCU_FANOUT if 64BIT
+ range 2 RCU_FANOUT if !64BIT
+ depends on TREE_RCU || TREE_PREEMPT_RCU
+ default 16
+ help
+ This option controls the leaf-level fanout of hierarchical
+ implementations of RCU, and allows trading off cache misses
+ against lock contention. Systems that synchronize their
+ scheduling-clock interrupts for energy-efficiency reasons will
+ want the default because the smaller leaf-level fanout keeps
+ lock contention levels acceptably low. Very large systems
+ (hundreds or thousands of CPUs) will instead want to set this
+ value to the maximum value possible in order to reduce the
+ number of cache misses incurred during RCU's grace-period
+ initialization. These systems tend to run CPU-bound, and thus
+ are not helped by synchronized interrupts, and thus tend to
+ skew them, which reduces lock contention enough that large
+ leaf-level fanouts work well.
+
+ Select a specific number if testing RCU itself.
+
+ Select the maximum permissible value for large systems.
+
+ Take the default if unsure.
+
config RCU_FANOUT_EXACT
bool "Disable tree-based hierarchical RCU auto-balancing"
depends on TREE_RCU || TREE_PREEMPT_RCU
@@ -518,10 +545,25 @@ config RCU_BOOST_PRIO
depends on RCU_BOOST
default 1
help
- This option specifies the real-time priority to which preempted
- RCU readers are to be boosted. If you are working with CPU-bound
- real-time applications, you should specify a priority higher then
- the highest-priority CPU-bound application.
+ This option specifies the real-time priority to which long-term
+ preempted RCU readers are to be boosted. If you are working
+ with a real-time application that has one or more CPU-bound
+ threads running at a real-time priority level, you should set
+ RCU_BOOST_PRIO to a priority higher then the highest-priority
+ real-time CPU-bound thread. The default RCU_BOOST_PRIO value
+ of 1 is appropriate in the common case, which is real-time
+ applications that do not have any CPU-bound threads.
+
+ Some real-time applications might not have a single real-time
+ thread that saturates a given CPU, but instead might have
+ multiple real-time threads that, taken together, fully utilize
+ that CPU. In this case, you should set RCU_BOOST_PRIO to
+ a priority higher than the lowest-priority thread that is
+ conspiring to prevent the CPU from running any non-real-time
+ tasks. For example, if one thread at priority 10 and another
+ thread at priority 5 are between themselves fully consuming
+ the CPU time on a given CPU, then RCU_BOOST_PRIO should be
+ set to priority 6 or higher.
Specify the real-time priority, or take the default if unsure.
@@ -1159,7 +1201,7 @@ menu "Kernel Performance Events And Counters"
config PERF_EVENTS
bool "Kernel performance events and counters"
- default y if (PROFILING || PERF_COUNTERS)
+ default y if PROFILING
depends on HAVE_PERF_EVENTS
select ANON_INODES
select IRQ_WORK
@@ -1186,18 +1228,6 @@ config PERF_EVENTS
Say Y if unsure.
-config PERF_COUNTERS
- bool "Kernel performance counters (old config option)"
- depends on HAVE_PERF_EVENTS
- help
- This config has been obsoleted by the PERF_EVENTS
- config option - please see that one for details.
-
- It has no effect on the kernel whether you enable
- it or not, it is a compatibility placeholder.
-
- Say N if unsure.
-
config DEBUG_PERF_USE_VMALLOC
default n
bool "Debug: use vmalloc to back perf mmap() buffers"
diff --git a/init/Makefile b/init/Makefile
index 0bf677aa0872..7bc47ee31c36 100644
--- a/init/Makefile
+++ b/init/Makefile
@@ -10,6 +10,10 @@ obj-$(CONFIG_BLK_DEV_INITRD) += initramfs.o
endif
obj-$(CONFIG_GENERIC_CALIBRATE_DELAY) += calibrate.o
+ifneq ($(CONFIG_ARCH_INIT_TASK),y)
+obj-y += init_task.o
+endif
+
mounts-y := do_mounts.o
mounts-$(CONFIG_BLK_DEV_RAM) += do_mounts_rd.o
mounts-$(CONFIG_BLK_DEV_INITRD) += do_mounts_initrd.o
diff --git a/init/do_mounts.c b/init/do_mounts.c
index 0e93f92a0345..42b0707c3481 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -472,7 +472,7 @@ void __init change_floppy(char *fmt, ...)
void __init mount_root(void)
{
#ifdef CONFIG_ROOT_NFS
- if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
+ if (ROOT_DEV == Root_NFS) {
if (mount_nfs_root())
return;
diff --git a/init/init_task.c b/init/init_task.c
new file mode 100644
index 000000000000..8b2f3996b035
--- /dev/null
+++ b/init/init_task.c
@@ -0,0 +1,24 @@
+#include <linux/init_task.h>
+#include <linux/export.h>
+#include <linux/mqueue.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+
+#include <asm/pgtable.h>
+#include <asm/uaccess.h>
+
+static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
+static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
+
+/* Initial task structure */
+struct task_struct init_task = INIT_TASK(init_task);
+EXPORT_SYMBOL(init_task);
+
+/*
+ * Initial thread structure. Alignment of this is handled by a special
+ * linker map entry.
+ */
+union thread_union init_thread_union __init_task_data =
+ { INIT_THREAD_INFO(init_task) };
diff --git a/init/main.c b/init/main.c
index 9d454f09f3b1..1ca6b32c4828 100644
--- a/init/main.c
+++ b/init/main.c
@@ -225,13 +225,9 @@ static int __init loglevel(char *str)
early_param("loglevel", loglevel);
-/*
- * Unknown boot options get handed to init, unless they look like
- * unused parameters (modprobe will find them in /proc/cmdline).
- */
-static int __init unknown_bootoption(char *param, char *val)
+/* Change NUL term back to "=", to make "param" the whole string. */
+static int __init repair_env_string(char *param, char *val, const char *unused)
{
- /* Change NUL term back to "=", to make "param" the whole string. */
if (val) {
/* param=val or param="val"? */
if (val == param+strlen(param)+1)
@@ -243,6 +239,16 @@ static int __init unknown_bootoption(char *param, char *val)
} else
BUG();
}
+ return 0;
+}
+
+/*
+ * Unknown boot options get handed to init, unless they look like
+ * unused parameters (modprobe will find them in /proc/cmdline).
+ */
+static int __init unknown_bootoption(char *param, char *val, const char *unused)
+{
+ repair_env_string(param, val, unused);
/* Handle obsolete-style parameters */
if (obsolete_checksetup(param))
@@ -379,7 +385,7 @@ static noinline void __init_refok rest_init(void)
}
/* Check for early params. */
-static int __init do_early_param(char *param, char *val)
+static int __init do_early_param(char *param, char *val, const char *unused)
{
const struct obs_kernel_param *p;
@@ -554,9 +560,6 @@ asmlinkage void __init start_kernel(void)
early_boot_irqs_disabled = false;
local_irq_enable();
- /* Interrupts are enabled now so all GFP allocations are safe. */
- gfp_allowed_mask = __GFP_BITS_MASK;
-
kmem_cache_init_late();
/*
@@ -722,21 +725,16 @@ static initcall_t *initcall_levels[] __initdata = {
};
static char *initcall_level_names[] __initdata = {
- "early parameters",
- "core parameters",
- "postcore parameters",
- "arch parameters",
- "subsys parameters",
- "fs parameters",
- "device parameters",
- "late parameters",
+ "early",
+ "core",
+ "postcore",
+ "arch",
+ "subsys",
+ "fs",
+ "device",
+ "late",
};
-static int __init ignore_unknown_bootoption(char *param, char *val)
-{
- return 0;
-}
-
static void __init do_initcall_level(int level)
{
extern const struct kernel_param __start___param[], __stop___param[];
@@ -747,7 +745,7 @@ static void __init do_initcall_level(int level)
static_command_line, __start___param,
__stop___param - __start___param,
level, level,
- ignore_unknown_bootoption);
+ &repair_env_string);
for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
do_one_initcall(*fn);
@@ -757,8 +755,13 @@ static void __init do_initcalls(void)
{
int level;
- for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
+ for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
+ pr_info("initlevel:%d=%s, %d registered initcalls\n",
+ level, initcall_level_names[level],
+ (int) (initcall_levels[level+1]
+ - initcall_levels[level]));
do_initcall_level(level);
+ }
}
/*
@@ -841,6 +844,10 @@ static int __init kernel_init(void * unused)
* Wait until kthreadd is all set-up.
*/
wait_for_completion(&kthreadd_done);
+
+ /* Now the scheduler is fully set up and can do blocking allocations */
+ gfp_allowed_mask = __GFP_BITS_MASK;
+
/*
* init can allocate pages on any node
*/