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-rw-r--r--init/Kconfig93
-rw-r--r--init/main.c19
2 files changed, 91 insertions, 21 deletions
diff --git a/init/Kconfig b/init/Kconfig
index b3782c6d5ed..f6281711166 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -588,6 +588,13 @@ config KALLSYMS_ALL
Say N.
+config KALLSYMS_STRIP_GENERATED
+ bool "Strip machine generated symbols from kallsyms"
+ depends on KALLSYMS_ALL
+ default y
+ help
+ Say N if you want kallsyms to retain even machine generated symbols.
+
config KALLSYMS_EXTRA_PASS
bool "Do an extra kallsyms pass"
depends on KALLSYMS
@@ -938,10 +945,90 @@ source "block/Kconfig"
config PREEMPT_NOTIFIERS
bool
+choice
+ prompt "RCU Implementation"
+ default CLASSIC_RCU
+
config CLASSIC_RCU
- def_bool !PREEMPT_RCU
+ bool "Classic RCU"
help
This option selects the classic RCU implementation that is
designed for best read-side performance on non-realtime
- systems. Classic RCU is the default. Note that the
- PREEMPT_RCU symbol is used to select/deselect this option.
+ systems.
+
+ Select this option if you are unsure.
+
+config TREE_RCU
+ bool "Tree-based hierarchical RCU"
+ help
+ This option selects the RCU implementation that is
+ designed for very large SMP system with hundreds or
+ thousands of CPUs.
+
+config PREEMPT_RCU
+ bool "Preemptible RCU"
+ depends on PREEMPT
+ help
+ This option reduces the latency of the kernel by making certain
+ RCU sections preemptible. Normally RCU code is non-preemptible, if
+ this option is selected then read-only RCU sections become
+ preemptible. This helps latency, but may expose bugs due to
+ now-naive assumptions about each RCU read-side critical section
+ remaining on a given CPU through its execution.
+
+endchoice
+
+config RCU_TRACE
+ bool "Enable tracing for RCU"
+ depends on TREE_RCU || PREEMPT_RCU
+ help
+ This option provides tracing in RCU which presents stats
+ in debugfs for debugging RCU implementation.
+
+ Say Y here if you want to enable RCU tracing
+ Say N if you are unsure.
+
+config RCU_FANOUT
+ int "Tree-based hierarchical RCU fanout value"
+ range 2 64 if 64BIT
+ range 2 32 if !64BIT
+ depends on TREE_RCU
+ default 64 if 64BIT
+ default 32 if !64BIT
+ help
+ This option controls the fanout of hierarchical implementations
+ of RCU, allowing RCU to work efficiently on machines with
+ large numbers of CPUs. This value must be at least the cube
+ root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit
+ systems and up to 262,144 for 64-bit systems.
+
+ Select a specific number if testing RCU itself.
+ Take the default if unsure.
+
+config RCU_FANOUT_EXACT
+ bool "Disable tree-based hierarchical RCU auto-balancing"
+ depends on TREE_RCU
+ default n
+ help
+ This option forces use of the exact RCU_FANOUT value specified,
+ regardless of imbalances in the hierarchy. This is useful for
+ testing RCU itself, and might one day be useful on systems with
+ strong NUMA behavior.
+
+ Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
+
+ Say N if unsure.
+
+config TREE_RCU_TRACE
+ def_bool RCU_TRACE && TREE_RCU
+ select DEBUG_FS
+ help
+ This option provides tracing for the TREE_RCU implementation,
+ permitting Makefile to trivially select kernel/rcutree_trace.c.
+
+config PREEMPT_RCU_TRACE
+ def_bool RCU_TRACE && PREEMPT_RCU
+ select DEBUG_FS
+ help
+ This option provides tracing for the PREEMPT_RCU implementation,
+ permitting Makefile to trivially select kernel/rcupreempt_trace.c.
diff --git a/init/main.c b/init/main.c
index 9d761aa5329..ad8f9f53f8d 100644
--- a/init/main.c
+++ b/init/main.c
@@ -75,15 +75,6 @@
#include <asm/smp.h>
#endif
-/*
- * This is one of the first .c files built. Error out early if we have compiler
- * trouble.
- */
-
-#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0
-#warning gcc-4.1.0 is known to miscompile the kernel. A different compiler version is recommended.
-#endif
-
static int kernel_init(void *);
extern void init_IRQ(void);
@@ -540,15 +531,6 @@ void __init __weak thread_info_cache_init(void)
{
}
-void __init __weak arch_early_irq_init(void)
-{
-}
-
-void __init __weak early_irq_init(void)
-{
- arch_early_irq_init();
-}
-
asmlinkage void __init start_kernel(void)
{
char * command_line;
@@ -681,6 +663,7 @@ asmlinkage void __init start_kernel(void)
efi_enter_virtual_mode();
#endif
thread_info_cache_init();
+ cred_init();
fork_init(num_physpages);
proc_caches_init();
buffer_init();