Peter Zijlstra
559fdc3c1b
perf_event: Optimize perf_output_lock()
...
The purpose of perf_output_{un,}lock() is to:
1) avoid publishing incomplete data
[ possible when publishing a head that is ahead of an entry
that is still being written ]
2) guarantee fwd progress
[ a simple refcount on pending writers doesn't need to drop to
0, making it so would end up implementing something like forced
quiecent states of RCU ]
To satisfy the above without undue complexity it serializes
between CPUs, this means that a pending writer can only be the
same cpu in a nested context, and since (under normal operation)
a cpu always makes progress we're good -- if the head is only
published when the bottom most writer completes.
Now we don't need to disable IRQs in order to serialize between
CPUs, disabling preemption ought to be sufficient, esp since we
already deal with nesting due to NMIs.
This avoids potentially expensive (and needless) local IRQ
disable/enable ops.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1258373161.26714.254.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-16 13:27:45 +01:00
..
gcov
microblaze: Enable GCOV_PROFILE_ALL
2009-09-21 14:29:21 +02:00
irq
genirq: try_one_irq() must be called with irq disabled
2009-11-07 21:44:45 +01:00
power
PM / Hibernate: Add newline to load_image() fail path
2009-11-03 11:03:09 +01:00
time
headers: remove sched.h from interrupt.h
2009-10-11 11:20:58 -07:00
trace
Merge commit 'v2.6.32-rc7' into perf/core
2009-11-15 09:50:41 +01:00
.gitignore
acct.c
bsdacct: switch credentials for writing to the accounting file
2009-08-24 11:33:40 +10:00
async.c
async: Fix lack of boot-time console due to insufficient synchronization
2009-06-08 12:31:53 -07:00
audit.c
Audit: send signal info if selinux is disabled
2009-09-24 03:50:26 -04:00
audit.h
Fix rule eviction order for AUDIT_DIR
2009-06-24 00:02:38 -04:00
audit_tree.c
Fix rule eviction order for AUDIT_DIR
2009-06-24 00:02:38 -04:00
audit_watch.c
Audit: reorganize struct audit_watch to save 8 bytes
2009-09-24 03:50:25 -04:00
auditfilter.c
Audit: clean up all op= output to include string quoting
2009-06-24 00:00:52 -04:00
auditsc.c
Audit: rearrange audit_context to save 16 bytes per struct
2009-09-24 03:50:26 -04:00
backtracetest.c
bounds.c
capability.c
cgroup.c
cgroup: fix strstrip() misuse
2009-10-29 07:39:25 -07:00
cgroup_freezer.c
cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time
2009-09-24 07:20:58 -07:00
compat.c
signals: implement sys_rt_tgsigqueueinfo
2009-04-30 19:24:24 +02:00
configs.c
cpu.c
Merge branch 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-09-15 09:19:38 -07:00
cpuset.c
cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time
2009-09-24 07:20:58 -07:00
cred-internals.h
cred.c
creds_are_invalid() needs to be exported for use by modules:
2009-09-23 11:02:26 -07:00
delayacct.c
headers: taskstats_kern.h trim
2009-09-18 09:48:52 -07:00
dma.c
exec_domain.c
Get rid of indirect include of fs_struct.h
2009-03-31 23:00:27 -04:00
exit.c
connector: fix regression introduced by sid connector
2009-10-29 07:39:25 -07:00
extable.c
Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-04-05 11:04:19 -07:00
fork.c
Correct nr_processes() when CPUs have been unplugged
2009-11-03 07:52:39 -08:00
freezer.c
sched: fix nr_uninterruptible accounting of frozen tasks really
2009-07-18 14:19:53 +02:00
futex.c
futex: Fix spurious wakeup for requeue_pi really
2009-10-28 20:34:34 +01:00
futex_compat.c
futex: Fix compat_futex to be same as futex for REQUEUE_PI
2009-08-10 15:41:12 +02:00
groups.c
groups: move code to kernel/groups.c
2009-06-16 19:47:48 -07:00
hrtimer.c
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-10-05 12:04:16 -07:00
hung_task.c
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
itimer.c
itimers: Add tracepoints for itimer
2009-08-29 14:10:07 +02:00
kallsyms.c
kallsyms: use new arch_is_kernel_text()
2009-09-23 07:39:30 -07:00
Kconfig.freezer
Kconfig.hz
Kconfig.preempt
kexec.c
kexec: fix omitting offset in extended crashkernel syntax
2009-07-29 19:10:34 -07:00
kfifo.c
kfifo: Use "const" definitions
2009-09-19 13:13:17 -07:00
kgdb.c
sysrq, intel_fb: fix sysrq g collision
2009-05-15 07:56:24 -05:00
kmod.c
Revert "kmod: fix race in usermodehelper code"
2009-09-23 18:12:10 -07:00
kprobes.c
const: constify remaining file_operations
2009-10-01 16:11:11 -07:00
ksysfs.c
kthread.c
sched: Fix kthread_bind() by moving the body of kthread_bind() to sched.c
2009-11-03 07:25:00 +01:00
latencytop.c
lockdep.c
tracing: Rename 'lockdep' event subsystem into 'lock'
2009-11-13 10:48:27 +01:00
lockdep_internals.h
lockdep: BFS cleanup
2009-07-24 10:53:29 +02:00
lockdep_proc.c
seq_file: constify seq_operations
2009-09-23 07:39:29 -07:00
lockdep_states.h
Makefile
cgroups: move the cgroup debug subsys into cgroup.c to access internal state
2009-09-24 07:20:57 -07:00
module.c
module: fix up CONFIG_KALLSYMS=n build.
2009-10-01 16:11:11 -07:00
mutex-debug.c
headers: remove sched.h from interrupt.h
2009-10-11 11:20:58 -07:00
mutex-debug.h
mutex.c
Merge branch 'linus' into perfcounters/core
2009-06-11 17:55:42 +02:00
mutex.h
notifier.c
ns_cgroup.c
cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time
2009-09-24 07:20:58 -07:00
nsproxy.c
nsproxy: extract create_nsproxy()
2009-06-18 13:03:56 -07:00
panic.c
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-10-08 12:16:35 -07:00
params.c
param: fix setting arrays of bool
2009-10-29 08:56:20 +10:30
perf_event.c
perf_event: Optimize perf_output_lock()
2009-11-16 13:27:45 +01:00
pid.c
mm: also use alloc_large_system_hash() for the PID hash table
2009-09-22 07:17:38 -07:00
pid_namespace.c
pidns: deny CLONE_PARENT|CLONE_NEWPID combination
2009-09-24 07:21:04 -07:00
pm_qos_params.c
posix-cpu-timers.c
itimers: Add tracepoints for itimer
2009-08-29 14:10:07 +02:00
posix-timers.c
time: Introduce CLOCK_REALTIME_COARSE
2009-08-21 21:43:46 +02:00
printk.c
printk: add printk_delay to make messages readable for some scenarios
2009-09-23 07:39:28 -07:00
profile.c
kernel/profile.c: Switch /proc/irq/prof_cpu_mask to seq_file
2009-09-20 20:15:40 +02:00
ptrace.c
ptrace: __ptrace_detach: do __wake_up_parent() if we reap the tracee
2009-09-24 07:20:59 -07:00
rcupdate.c
rcu: Move rcu_barrier() to rcutree
2009-10-07 08:11:20 +02:00
rcutorture.c
rcu: Clean up code to address Ingo's checkpatch feedback
2009-09-23 19:46:30 +02:00
rcutree.c
rcu: Fix long-grace-period race between forcing and initialization
2009-11-02 16:06:21 +01:00
rcutree.h
rcu: Fix long-grace-period race between forcing and initialization
2009-11-02 16:06:21 +01:00
rcutree_plugin.h
rcu: Fix TREE_PREEMPT_RCU CPU_HOTPLUG bad-luck hang
2009-10-15 20:33:01 +02:00
rcutree_trace.c
rcu: Make hot-unplugged CPU relinquish its own RCU callbacks
2009-10-07 08:11:20 +02:00
relay.c
const: mark struct vm_struct_operations
2009-09-27 11:39:25 -07:00
res_counter.c
memcg: some modification to softlimit under hierarchical memory reclaim.
2009-10-01 16:11:13 -07:00
resource.c
walk system ram range
2009-09-23 07:39:41 -07:00
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c
rtmutex: Avoid deadlock in rt_mutex_start_proxy_lock()
2009-08-06 05:50:21 +02:00
rtmutex.h
rtmutex_common.h
rt_mutex: add proxy lock routines
2009-04-06 11:14:02 +02:00
rwsem.c
sched.c
sched: Use root_task_group_empty only with FAIR_GROUP_SCHED
2009-11-08 13:15:48 +01:00
sched_clock.c
sched_clock: Fix atomicity/continuity bug by using cmpxchg64()
2009-09-30 22:56:10 +02:00
sched_cpupri.c
sched: Add new prio to cpupri before removing old prio
2009-08-02 14:26:09 +02:00
sched_cpupri.h
cpumask: remove cpumask_t from core
2009-03-30 22:05:17 +10:30
sched_debug.c
sched: Add new wakeup preemption mode: WAKEUP_RUNNING
2009-09-17 10:17:25 +02:00
sched_fair.c
sched: Strengthen buddies and mitigate buddy induced latencies
2009-10-23 23:48:28 +02:00
sched_features.h
sched: Add new wakeup preemption mode: WAKEUP_RUNNING
2009-09-17 10:17:25 +02:00
sched_idletask.c
sched: Simplify sys_sched_rr_get_interval() system call
2009-09-21 09:53:55 +02:00
sched_rt.c
sched: Simplify sys_sched_rr_get_interval() system call
2009-09-21 09:53:55 +02:00
sched_stats.h
sched: remove unused fields from struct rq
2009-03-24 23:16:51 +01:00
seccomp.c
semaphore.c
signal.c
signals: inline __fatal_signal_pending
2009-09-24 07:21:01 -07:00
slow-work.c
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
smp.c
cpumask: remove arch_send_call_function_ipi
2009-09-24 09:34:47 +09:30
softirq.c
softirq: add BLOCK_IOPOLL to softirq_to_name
2009-09-17 15:53:44 -04:00
softlockup.c
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
spinlock.c
locking: Allow arch-inlined spinlocks
2009-08-31 18:08:50 +02:00
srcu.c
stacktrace.c
stop_machine.c
cpumask: remove cpumask_t from core
2009-03-30 22:05:17 +10:30
sys.c
Merge branch 'hwpoison-2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
2009-10-29 08:20:00 -07:00
sys_ni.c
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
2009-09-24 15:13:11 -07:00
sysctl.c
Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
2009-09-24 07:53:22 -07:00
sysctl_check.c
sysctl: fix false positives when PROC_SYSCTL=n
2009-10-29 07:39:30 -07:00
taskstats.c
genetlink: make netns aware
2009-07-12 14:03:27 -07:00
test_kprobes.c
time.c
time: Prevent 32 bit overflow with set_normalized_timespec()
2009-09-15 10:17:30 +02:00
timeconst.pl
timer.c
Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-09-23 09:46:15 -07:00
tracepoint.c
trivial: fix typo "to to" in multiple files
2009-09-21 15:14:55 +02:00
tsacct.c
uid16.c
headers: utsname.h redux
2009-09-23 18:13:10 -07:00
up.c
user.c
uids: Prevent tear down race
2009-11-02 16:02:39 +01:00
user_namespace.c
utsname.c
utsns: extract creeate_uts_ns()
2009-06-18 13:03:55 -07:00
utsname_sysctl.c
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
wait.c
locking, sched: Give waitqueue spinlocks their own lockdep classes
2009-08-10 14:43:09 +02:00
workqueue.c
Merge branch 'hwpoison-2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
2009-10-29 08:20:00 -07:00