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-rw-r--r--init/Kconfig71
-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, 113 insertions, 45 deletions
diff --git a/init/Kconfig b/init/Kconfig
index b5dff4d1e1d..ccb5248474c 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -27,6 +27,9 @@ config IRQ_WORK
bool
depends on HAVE_IRQ_WORK
+config BUILDTIME_EXTABLE_SORT
+ bool
+
menu "General setup"
config EXPERIMENTAL
@@ -458,6 +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
@@ -515,10 +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.
@@ -1284,7 +1329,7 @@ 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
@@ -1311,18 +1356,6 @@ 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"
@@ -1542,8 +1575,8 @@ endif # MODULES
config INIT_ALL_POSSIBLE
bool
help
- Back when each arch used to define their own cpu_online_map and
- cpu_possible_map, some of them chose to initialize cpu_possible_map
+ Back when each arch used to define their own cpu_online_mask and
+ cpu_possible_mask, some of them chose to initialize cpu_possible_mask
with all 1s, and others with all 0s. When they were centralised,
it was better to provide this option than to break all the archs
and have several arch maintainers pursuing me down dark alleys.
diff --git a/init/Makefile b/init/Makefile
index 0bf677aa087..7bc47ee31c3 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 0e93f92a034..42b0707c348 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 00000000000..8b2f3996b03
--- /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 9d454f09f3b..1ca6b32c482 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
*/