diff options
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 30 | ||||
| -rw-r--r-- | init/main.c | 19 |
2 files changed, 43 insertions, 6 deletions
diff --git a/init/Kconfig b/init/Kconfig index f068071fcc5..5a3ad5c20e2 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -869,6 +869,36 @@ config AIO by some high performance threaded applications. Disabling this option saves about 7k. +config HAVE_PERF_COUNTERS + bool + +menu "Performance Counters" + +config PERF_COUNTERS + bool "Kernel Performance Counters" + depends on HAVE_PERF_COUNTERS + default y + select ANON_INODES + help + Enable kernel support for performance counter hardware. + + Performance counters are special hardware registers available + on most modern CPUs. These registers count the number of certain + types of hw events: such as instructions executed, cachemisses + suffered, or branches mis-predicted - without slowing down the + kernel or applications. These registers can also trigger interrupts + when a threshold number of events have passed - and can thus be + used to profile the code that runs on that CPU. + + The Linux Performance Counter subsystem provides an abstraction of + these hardware capabilities, available via a system call. It + provides per task and per CPU counters, and it provides event + capabilities on top of those. + + Say Y if unsure. + +endmenu + config VM_EVENT_COUNTERS default y bool "Enable VM event counters for /proc/vmstat" if EMBEDDED diff --git a/init/main.c b/init/main.c index 83697e160b3..6bf83afd654 100644 --- a/init/main.c +++ b/init/main.c @@ -14,6 +14,7 @@ #include <linux/proc_fs.h> #include <linux/kernel.h> #include <linux/syscalls.h> +#include <linux/stackprotector.h> #include <linux/string.h> #include <linux/ctype.h> #include <linux/delay.h> @@ -135,14 +136,14 @@ unsigned int __initdata setup_max_cpus = NR_CPUS; * greater than 0, limits the maximum number of CPUs activated in * SMP mode to <NUM>. */ -#ifndef CONFIG_X86_IO_APIC -static inline void disable_ioapic_setup(void) {}; -#endif + +void __weak arch_disable_smp_support(void) { } static int __init nosmp(char *str) { setup_max_cpus = 0; - disable_ioapic_setup(); + arch_disable_smp_support(); + return 0; } @@ -152,14 +153,14 @@ static int __init maxcpus(char *str) { get_option(&str, &setup_max_cpus); if (setup_max_cpus == 0) - disable_ioapic_setup(); + arch_disable_smp_support(); return 0; } early_param("maxcpus", maxcpus); #else -#define setup_max_cpus NR_CPUS +const unsigned int setup_max_cpus = NR_CPUS; #endif /* @@ -540,6 +541,12 @@ asmlinkage void __init start_kernel(void) */ lockdep_init(); debug_objects_early_init(); + + /* + * Set up the the initial canary ASAP: + */ + boot_init_stack_canary(); + cgroup_init_early(); local_irq_disable(); |