Frederic Weisbecker
abf917cd91
cputime: Generic on-demand virtual cputime accounting ...
If we want to stop the tick further idle, we need to be
able to account the cputime without using the tick.
Virtual based cputime accounting solves that problem by
hooking into kernel/user boundaries.
However implementing CONFIG_VIRT_CPU_ACCOUNTING require
low level hooks and involves more overhead. But we already
have a generic context tracking subsystem that is required
for RCU needs by archs which plan to shut down the tick
outside idle.
This patch implements a generic virtual based cputime
accounting that relies on these generic kernel/user hooks.
There are some upsides of doing this:
- This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING
if context tracking is already built (already necessary for RCU in full
tickless mode).
- We can rely on the generic context tracking subsystem to dynamically
(de)activate the hooks, so that we can switch anytime between virtual
and tick based accounting. This way we don't have the overhead
of the virtual accounting when the tick is running periodically.
And one downside:
- There is probably more overhead than a native virtual based cputime
accounting. But this relies on hooks that are already set anyway.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-01-27 19:23:27 +01:00
KGDB/KDB fixes and cleanups
2012-10-13 11:16:58 +09:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2012-12-17 15:44:47 -08:00
irq: tsk->comm is an array
2012-12-18 15:02:11 -08:00
Merge branch 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2012-12-12 08:18:24 -08:00
cputime: Generic on-demand virtual cputime accounting
2013-01-27 19:23:27 +01:00
Merge tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
2012-12-13 15:31:08 -08:00
tracing: Fix regression of trace_pipe
2013-01-14 13:13:32 -05:00
vfs: make path_openat take a struct filename pointer
2012-10-12 20:15:09 -04:00
module, async: async_synchronize_full() on module init iff async is used
2013-01-16 09:05:33 -08:00
kernel/audit.c: avoid negative sleep durations
2013-01-11 14:54:56 -08:00
audit: optimize audit_compare_dname_path
2012-10-12 00:32:02 -04:00
audit: catch possible NULL audit buffers
2013-01-11 14:54:55 -08:00
audit: catch possible NULL audit buffers
2013-01-11 14:54:55 -08:00
audit: fix auditfilter.c kernel-doc warnings
2013-01-10 14:35:23 -08:00
audit: catch possible NULL audit buffers
2013-01-11 14:54:55 -08:00
Merge branch 'akpm' (Andrew's patch-bomb)
2012-12-17 20:58:12 -08:00
cgroup: rename ->create/post_create/pre_destroy/destroy() to ->css_alloc/online/offline/free()
2012-11-19 08:13:38 -08:00
compat: generic compat_sys_sched_rr_get_interval() implementation
2012-12-17 17:15:18 -08:00
cputime: Generic on-demand virtual cputime accounting
2013-01-27 19:23:27 +01:00
Merge branch 'x86-bsp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2012-12-11 19:56:33 -08:00
kernel/cpu_pm.c: fix various typos
2012-05-31 17:49:27 -07:00
cpuset: use N_MEMORY instead N_HIGH_MEMORY
2012-12-12 17:38:32 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2012-12-18 10:55:28 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2012-12-17 15:44:47 -08:00
pidns: Outlaw thread creation after unshare(CLONE_NEWPID)
2012-12-24 22:53:14 -08:00
freezer: change ptrace_stop/do_signal_stop to use freezable_schedule()
2012-10-26 14:27:49 -07:00
futex: avoid wake_futex() for a PI futex_q
2012-11-26 17:41:24 -08:00
hrtimer: Update hrtimer base offsets each hrtimer_interrupt
2012-07-11 23:34:39 +02:00
jump_label: Export jump_label_rate_limit()
2012-08-06 19:00:35 +03:00
vsprintf: fix %ps on non symbols when using kallsyms
2012-05-29 16:22:32 -07:00
kcmp: include linux/ptrace.h
2012-12-20 17:40:19 -08:00
locking: Adjust spin lock inlining Kconfig options
2012-09-13 17:56:13 +02:00
kdump: remove unneeded include
2012-10-06 03:05:19 +09:00
Bury the conditionals from kernel_thread/kernel_execve series
2012-12-19 18:07:38 -05:00
kprobes/x86: Fix to support jprobes on ftrace-based kprobe
2012-09-13 22:52:11 -04:00
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2012-12-11 18:10:49 -08:00
kthread: use N_MEMORY instead N_HIGH_MEMORY
2012-12-12 17:38:33 -08:00
brlocks/lglocks: turn into functions
2012-05-29 23:28:41 -04:00
lockdep: Check if nested lock is actually held
2012-09-13 17:00:44 +02:00
lockdep: Use KSYM_NAME_LEN'ed buffer for __get_key_name()
2012-10-24 12:39:09 +02:00
Nothing all that exciting; a new module-from-fd syscall for those who want
2012-12-19 07:55:08 -08:00
MODSIGN: Avoid using .incbin in C source
2012-12-14 13:06:44 +10:30
keys: use keyring_alloc() to create module signing keyring
2012-12-20 17:40:21 -08:00
MODSIGN: Move the magic string to the end of a module and eliminate the search
2012-10-19 17:30:40 -07:00
module, async: async_synchronize_full() on module init iff async is used
2013-01-16 09:05:33 -08:00
MODSIGN: Don't use enum-type bitfields in module signature info block
2012-12-05 11:27:24 +10:30
userns: Implement unshare of the user namespace
2012-11-20 04:18:14 -08:00
padata: use __this_cpu_read per-cpu helper
2012-12-06 17:16:23 +08:00
panic: fix a possible deadlock in panic()
2012-07-30 17:25:13 -07:00
pidns: Stop pid allocation when init dies
2012-12-25 16:10:05 -08:00
pidns: Stop pid allocation when init dies
2012-12-25 16:10:05 -08:00
A few /dev/random improvements for the v3.8 merge window.
2012-12-19 20:23:37 -08:00
printk: fix incorrect length from print_time() when seconds > 99999
2013-01-04 16:11:48 -08:00
propagate name change to comments in kernel source
2012-12-06 10:39:54 +01:00
Merge branch 'akpm' (Andrew's patch-bomb)
2012-12-17 20:58:12 -08:00
rcu: Add a module parameter to force use of expedited RCU primitives
2012-10-23 14:54:08 -07:00
rcu: Add a module parameter to force use of expedited RCU primitives
2012-10-23 14:54:08 -07:00
rcu: Fix TINY_RCU rcu_is_cpu_rrupt_from_idle check
2012-11-13 14:08:34 -08:00
rcu: Add a module parameter to force use of expedited RCU primitives
2012-10-23 14:54:08 -07:00
Merge branches 'urgent.2012.10.27a', 'doc.2012.11.16a', 'fixes.2012.11.13a', 'srcu.2012.10.27a', 'stall.2012.11.13a', 'tracing.2012.11.08a' and 'idle.2012.10.24a' into HEAD
2012-11-16 09:59:58 -08:00
context_tracking: New context tracking susbsystem
2012-11-30 11:40:07 -08:00
rcu: Separate accounting of callbacks from callback-free CPUs
2012-11-16 10:05:57 -08:00
rcu: Separate accounting of callbacks from callback-free CPUs
2012-11-16 10:05:57 -08:00
rcu: Separate accounting of callbacks from callback-free CPUs
2012-11-16 10:05:57 -08:00
splice: fix racy pipe->buffers uses
2012-06-13 21:16:42 +02:00
res_counter: return amount of charges after res_counter_uncharge()
2012-12-18 15:02:12 -08:00
kernel/resource.c: fix stack overflow in __reserve_region_with_split()
2012-10-06 03:05:31 +09:00
lockdep, rwsem: provide down_write_nest_lock()
2013-01-11 14:54:55 -08:00
seccomp: Make syscall skipping and nr changes more consistent
2012-10-02 21:14:29 +10:00
signals: set_current_blocked() can use __set_current_blocked()
2013-01-05 19:34:54 -08:00
smp: Remove ipi_call_lock[_irq]()/ipi_call_unlock[_irq]()
2012-06-05 17:27:14 +02:00
hotplug: Fix UP bug in smpboot hotplug code
2012-08-13 17:01:07 +02:00
smpboot: Provide infrastructure for percpu hotplug threads
2012-08-13 17:01:07 +02:00
cputime: Specialize irq vtime hooks
2012-10-29 21:31:32 +01:00
Merge branches 'urgent.2012.10.27a', 'doc.2012.11.16a', 'fixes.2012.11.13a', 'srcu.2012.10.27a', 'stall.2012.11.13a', 'tracing.2012.11.08a' and 'idle.2012.10.24a' into HEAD
2012-11-16 09:59:58 -08:00
cputime: Rename thread_group_times to thread_group_cputime_adjusted
2012-11-28 17:07:57 +01:00
module: add syscall to load module from fd
2012-12-14 13:05:22 +10:30
Automatic NUMA Balancing V11
2012-12-16 15:18:08 -08:00
pidns: Use task_active_pid_ns where appropriate
2012-11-19 05:59:09 -08:00
task_work: task_work_add() should not succeed after exit_task_work()
2012-09-13 16:47:34 +02:00
taskstats: cgroupstats_user_cmd() may leak on error
2012-10-06 03:05:31 +09:00
time: Move update_vsyscall definitions to timekeeper_internal.h
2012-09-24 12:38:06 -04:00
timers: Fix endless looping between cascade() and internal_add_timer()
2012-10-09 21:27:14 +02:00
userns: Convert taskstats to handle the user and pid namespaces.
2012-09-18 01:01:32 -07:00
proc: Usable inode numbers for the namespace file descriptors.
2012-11-20 04:19:49 -08:00
userns: Fix typo in description of the limitation of userns_install
2012-12-14 18:36:36 -08:00
userns: Require CAP_SYS_ADMIN for most uses of setns.
2012-12-14 16:12:03 -08:00
propagate name change to comments in kernel source
2012-12-06 10:39:54 +01:00
watchdog: Fix disable/enable regression
2012-12-19 12:10:33 -08:00
Merge branch 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2012-12-12 08:15:13 -08:00
abf917cd91