diff options
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 34 | ||||
| -rw-r--r-- | init/main.c | 41 |
2 files changed, 61 insertions, 14 deletions
diff --git a/init/Kconfig b/init/Kconfig index d4e9671347e..9b68fee8d79 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -933,6 +933,40 @@ 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 + 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. + +config EVENT_PROFILE + bool "Tracepoint profile sources" + depends on PERF_COUNTERS && EVENT_TRACER + default y + +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 9d759d68d7a..5616661eac0 100644 --- a/init/main.c +++ b/init/main.c @@ -534,6 +534,16 @@ void __init __weak thread_info_cache_init(void) { } +/* + * Set up kernel memory allocators + */ +static void __init mm_init(void) +{ + mem_init(); + kmem_cache_init(); + vmalloc_init(); +} + asmlinkage void __init start_kernel(void) { char * command_line; @@ -575,6 +585,23 @@ asmlinkage void __init start_kernel(void) setup_nr_cpu_ids(); smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ + build_all_zonelists(); + page_alloc_init(); + + printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line); + parse_early_param(); + parse_args("Booting kernel", static_command_line, __start___param, + __stop___param - __start___param, + &unknown_bootoption); + /* + * These use large bootmem allocations and must precede + * kmem_cache_init() + */ + pidhash_init(); + vfs_caches_init_early(); + sort_main_extable(); + trap_init(); + mm_init(); /* * Set up the scheduler prior starting any interrupts (such as the * timer interrupt). Full topology setup happens at smp_init() @@ -586,26 +613,16 @@ asmlinkage void __init start_kernel(void) * fragile until we cpu_idle() for the first time. */ preempt_disable(); - build_all_zonelists(); - page_alloc_init(); - printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line); - parse_early_param(); - parse_args("Booting kernel", static_command_line, __start___param, - __stop___param - __start___param, - &unknown_bootoption); if (!irqs_disabled()) { printk(KERN_WARNING "start_kernel(): bug: interrupts were " "enabled *very* early, fixing it\n"); local_irq_disable(); } - sort_main_extable(); - trap_init(); rcu_init(); /* init some links before init_ISA_irqs() */ early_irq_init(); init_IRQ(); prio_tree_init(); - pidhash_init(); init_timers(); hrtimers_init(); softirq_init(); @@ -647,14 +664,10 @@ asmlinkage void __init start_kernel(void) initrd_start = 0; } #endif - vmalloc_init(); - vfs_caches_init_early(); cpuset_init_early(); page_cgroup_init(); - mem_init(); enable_debug_pagealloc(); cpu_hotplug_init(); - kmem_cache_init(); kmemtrace_init(); kmemleak_init(); debug_objects_mem_init(); |