diff options
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 224 | ||||
| -rw-r--r-- | init/do_mounts.c | 13 | ||||
| -rw-r--r-- | init/do_mounts_md.c | 5 | ||||
| -rw-r--r-- | init/main.c | 3 |
4 files changed, 129 insertions, 116 deletions
diff --git a/init/Kconfig b/init/Kconfig index 2af83825634..6a5c5fed66c 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -238,6 +238,98 @@ config AUDIT_TREE def_bool y depends on AUDITSYSCALL && INOTIFY +menu "RCU Subsystem" + +choice + prompt "RCU Implementation" + default CLASSIC_RCU + +config CLASSIC_RCU + bool "Classic RCU" + help + This option selects the classic RCU implementation that is + designed for best read-side performance on non-realtime + 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. + +endmenu # "RCU Subsystem" + config IKCONFIG tristate "Kernel .config support" ---help--- @@ -541,6 +633,14 @@ config PID_NS Unless you want to work with an experimental feature say N here. +config NET_NS + bool "Network namespace" + default n + depends on NAMESPACES && EXPERIMENTAL && NET + help + Allow user space to create what appear to be multiple instances + of the network stack. + config BLK_DEV_INITRD bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" depends on BROKEN || !FRV @@ -575,6 +675,9 @@ config CC_OPTIMIZE_FOR_SIZE config SYSCTL bool +config ANON_INODES + bool + menuconfig EMBEDDED bool "Configure standard kernel features (for small systems)" help @@ -625,13 +728,6 @@ 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 @@ -687,18 +783,6 @@ config PCSPKR_PLATFORM This option allows to disable the internal PC-Speaker support, saving some memory. -config COMPAT_BRK - bool "Disable heap randomization" - default y - help - Randomizing heap placement makes heap exploits harder, but it - also breaks ancient binaries (including anything libc5 based). - This option changes the bootup default to heap randomization - disabled, and can be overriden runtime by setting - /proc/sys/kernel/randomize_va_space to 2. - - On non-ancient distros (post-2000 ones) N is usually a safe choice. - config BASE_FULL default y bool "Enable full-sized data structures for core" if EMBEDDED @@ -716,9 +800,6 @@ config FUTEX support for "fast userspace mutexes". The resulting kernel may not run glibc-based applications correctly. -config ANON_INODES - bool - config EPOLL bool "Enable eventpoll support" if EMBEDDED default y @@ -804,6 +885,18 @@ config SLUB_DEBUG SLUB sysfs support. /sys/slab will not exist and there will be no support for cache validation etc. +config COMPAT_BRK + bool "Disable heap randomization" + default y + help + Randomizing heap placement makes heap exploits harder, but it + also breaks ancient binaries (including anything libc5 based). + This option changes the bootup default to heap randomization + disabled, and can be overriden runtime by setting + /proc/sys/kernel/randomize_va_space to 2. + + On non-ancient distros (post-2000 ones) N is usually a safe choice. + choice prompt "Choose SLAB allocator" default SLUB @@ -972,90 +1065,3 @@ source "block/Kconfig" config PREEMPT_NOTIFIERS bool -choice - prompt "RCU Implementation" - default CLASSIC_RCU - -config CLASSIC_RCU - bool "Classic RCU" - help - This option selects the classic RCU implementation that is - designed for best read-side performance on non-realtime - 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/do_mounts.c b/init/do_mounts.c index 708105e163d..8d4ff5afc1d 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -370,10 +370,14 @@ void __init prepare_namespace(void) ssleep(root_delay); } - /* wait for the known devices to complete their probing */ - while (driver_probe_done() != 0) - msleep(100); - async_synchronize_full(); + /* + * wait for the known devices to complete their probing + * + * Note: this is a potential source of long boot delays. + * For example, it is not atypical to wait 5 seconds here + * for the touchpad of a laptop to initialize. + */ + wait_for_device_probe(); md_run_setup(); @@ -399,6 +403,7 @@ void __init prepare_namespace(void) while (driver_probe_done() != 0 || (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) msleep(100); + async_synchronize_full(); } is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR; diff --git a/init/do_mounts_md.c b/init/do_mounts_md.c index ff95e319288..9bdddbcb3d6 100644 --- a/init/do_mounts_md.c +++ b/init/do_mounts_md.c @@ -281,8 +281,9 @@ static void __init autodetect_raid(void) */ printk(KERN_INFO "md: Waiting for all devices to be available before autodetect\n"); printk(KERN_INFO "md: If you don't use raid, use raid=noautodetect\n"); - while (driver_probe_done() < 0) - msleep(100); + + wait_for_device_probe(); + fd = sys_open("/dev/md0", 0, 0); if (fd >= 0) { sys_ioctl(fd, RAID_AUTORUN, raid_autopart); diff --git a/init/main.c b/init/main.c index 844209453c0..83697e160b3 100644 --- a/init/main.c +++ b/init/main.c @@ -97,7 +97,7 @@ static inline void mark_rodata_ro(void) { } extern void tc_init(void); #endif -enum system_states system_state; +enum system_states system_state __read_mostly; EXPORT_SYMBOL(system_state); /* @@ -463,6 +463,7 @@ static noinline void __init_refok rest_init(void) * at least once to get things moving: */ init_idle_bootup_task(current); + rcu_scheduler_starting(); preempt_enable_no_resched(); schedule(); preempt_disable(); |