Mathieu Desnoyers
6496968e6c
markers: use synchronize_sched() ...
Markers do not mix well with CONFIG_PREEMPT_RCU because it uses
preempt_disable/enable() and not rcu_read_lock/unlock for minimal
intrusiveness. We would need call_sched and sched_barrier primitives.
Currently, the modification (connection and disconnection) of probes
from markers requires changes to the data structure done in RCU-style :
a new data structure is created, the pointer is changed atomically, a
quiescent state is reached and then the old data structure is freed.
The quiescent state is reached once all the currently running
preempt_disable regions are done running. We use the call_rcu mechanism
to execute kfree() after such quiescent state has been reached.
However, the new CONFIG_PREEMPT_RCU version of call_rcu and rcu_barrier
does not guarantee that all preempt_disable code regions have finished,
hence the race.
The "proper" way to do this is to use rcu_read_lock/unlock, but we don't
want to use it to minimize intrusiveness on the traced system. (we do
not want the marker code to call into much of the OS code, because it
would quickly restrict what can and cannot be instrumented, such as the
scheduler).
The temporary fix, until we get call_rcu_sched and rcu_barrier_sched in
mainline, is to use synchronize_sched before each call_rcu calls, so we
wait for the quiescent state in the system call code path. It will slow
down batch marker enable/disable, but will make sure the race is gone.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-02 15:28:19 -07:00
genirq: do not leave interupts enabled on free_irq
2008-02-19 10:43:58 +01:00
Merge branches 'release' and 'doc' into release
2008-03-13 01:59:53 -04:00
clocksource: revert: use init_timer_deferrable for clocksource_watchdog
2008-03-25 20:13:25 +01:00
Update kernel/.gitignore with new auto-generated files
2008-02-09 23:27:01 -08:00
bsd_acct: using task_struct->tgid is not right in pid-namespaces
2008-03-24 19:22:20 -07:00
audit: silence two kerneldoc warnings in kernel/audit.c
2008-03-28 14:45:21 -07:00
[PATCH] audit: watching subtrees
2007-10-21 02:37:45 -04:00
Introduce path_put()
2008-02-14 21:13:33 -08:00
Introduce path_put()
2008-02-14 21:13:33 -08:00
[PATCH] Audit: Fix the format type for size_t variables
2008-03-01 07:16:06 -05:00
x86: add a simple backtrace test module
2008-01-30 13:33:08 +01:00
Add 64-bit capability support to the kernel
2008-02-05 09:44:20 -08:00
NULL noise: fs/*, mm/*, kernel/*
2008-03-30 14:18:41 -07:00
Task Control Groups: simple task cgroup debug info subsystem
2007-10-19 11:53:36 -07:00
hrtimer: don't modify restart_block->fn in restart functions
2008-02-10 10:48:03 +01:00
use simple_read_from_buffer in kernel/
2007-05-09 12:30:49 -07:00
cpu: fix section mismatch warnings for enable_nonboot_cpus
2008-02-08 09:22:41 -08:00
cpusets: fix obsolete comment
2008-03-05 17:53:33 -08:00
Add scaled time to taskstats based process accounting
2007-10-18 14:37:28 -07:00
whitespace fixes: DMA channel allocator
2007-10-18 14:37:24 -07:00
whitespace fixes: execution domains
2007-10-18 14:37:26 -07:00
Fix waitid si_code regression
2008-03-08 11:54:00 -08:00
module: Don't report discarded init pages as kernel text.
2008-01-29 17:13:18 +11:00
memcgroup: fix spurious EBUSY on memory cgroup removal
2008-03-28 14:45:21 -07:00
NULL noise: fs/*, mm/*, kernel/*
2008-03-30 14:18:41 -07:00
futex_compat __user annotation
2008-03-30 14:18:41 -07:00
hrtimer: catch expired CLOCK_REALTIME timers early
2008-02-14 22:08:30 +01:00
ITIMER_REAL: convert to use struct pid
2008-02-08 09:22:29 -08:00
remove support for un-needed _extratext section
2008-02-06 10:41:01 -08:00
sched: high-res preemption tick
2008-01-25 21:08:29 +01:00
rcu: move PREEMPT_RCU config option back under PREEMPT
2008-03-10 18:01:20 -07:00
vmcoreinfo: add "VMCOREINFO_" to all the call for vmcoreinfo_append_str()
2008-02-07 08:42:25 -08:00
is_power_of_2: kernel/kfifo.c
2007-07-16 09:05:50 -07:00
Dont touch fs_struct in usermodehelper
2008-02-14 21:13:32 -08:00
kprobes: fix a null pointer bug in register_kretprobe()
2008-03-04 16:35:19 -08:00
Kobject: convert remaining kobject_unregister() to kobject_put()
2008-01-24 20:40:40 -08:00
sched: fix, always create kernel threads with normal priority
2008-01-25 21:08:33 +01:00
sched: latencytop support
2008-01-25 21:08:34 +01:00
Subject: lockdep: include all lock classes in all_lock_classes
2008-02-25 23:03:02 +01:00
[PATCH] lockdep: more chains
2006-12-07 08:39:43 -08:00
lockdep: Avoid /proc/lockdep & lock_stat infinite output
2007-10-11 22:11:11 +02:00
avoid overflows in kernel/time.c
2008-02-08 09:22:39 -08:00
markers: use synchronize_sched()
2008-04-02 15:28:19 -07:00
modules: warn about suspicious return values from module's ->init() hook
2008-03-10 18:01:20 -07:00
kernel: remove fastcall in kernel/*
2008-02-08 09:22:31 -08:00
[PATCH] lockdep: better lock debugging
2006-07-03 15:27:01 -07:00
kernel: remove fastcall in kernel/*
2008-02-08 09:22:31 -08:00
[PATCH] lockdep: prove mutex locking correctness
2006-07-03 15:27:04 -07:00
kernel/notifier.c should #include <linux/reboot.h>
2008-02-06 10:41:02 -08:00
cgroups: implement namespace tracking subsystem
2007-10-19 11:53:37 -07:00
namespaces: move the IPC namespace under IPC_NS option
2008-02-08 09:22:23 -08:00
ACPI: Taint kernel on ACPI table override (format corrected)
2008-02-06 22:07:51 -05:00
Add new string functions strict_strto* and convert kernel params to use them
2008-02-08 09:22:41 -08:00
kernel: remove fastcall in kernel/*
2008-02-08 09:22:31 -08:00
namespaces: cleanup the code managed with PID_NS option
2008-02-08 09:22:23 -08:00
pm qos infrastructure and interface
2008-02-05 09:44:22 -08:00
Use find_task_by_vpid in posix timers
2008-02-08 09:22:41 -08:00
hrtimer: check relative timeouts for overflow
2008-02-14 22:08:30 +01:00
Make printk() console semaphore accesses sensible
2008-03-24 19:25:08 -07:00
Nuke a duplicate include from profile.c
2008-02-08 09:22:34 -08:00
ptrace_check_attach: remove unneeded ->signal != NULL check
2008-02-08 09:22:26 -08:00
Preempt-RCU: implementation
2008-01-25 21:08:24 +01:00
rcupdate: fix comment
2008-02-13 16:21:18 -08:00
rcupreempt: remove never-migrates assumption from rcu_process_callbacks()
2008-02-29 20:21:13 +01:00
Preempt-RCU: implementation
2008-01-25 21:08:24 +01:00
cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus()
2008-01-25 21:08:02 +01:00
relay: set an spd_release() hook for splice
2008-03-26 12:04:09 +01:00
Memory Resource Controller use strstrip while parsing arguments
2008-03-04 16:35:09 -08:00
[POWERPC] Add arch-specific walk_memory_remove() for 64-bit powerpc
2008-02-08 19:52:48 +11:00
Don't operate with pid_t in rtmutex tester
2008-02-08 09:22:41 -08:00
[PATCH] lockdep: better lock debugging
2006-07-03 15:27:01 -07:00
Driver core: change sysdev classes to use dynamic kobject names
2008-01-24 20:40:40 -08:00
hrtimer: more hrtimer_init_sleeper() fallout.
2008-02-13 15:45:36 +01:00
[PATCH] lockdep: better lock debugging
2006-07-03 15:27:01 -07:00
Don't operate with pid_t in rtmutex tester
2008-02-08 09:22:41 -08:00
sched: mark rwsem functions as __sched for wchan/profiling
2007-12-18 15:21:13 +01:00
NOHZ: reevaluate idle sleep length after add_timer_on()
2008-03-26 08:28:55 +01:00
sched: improve affine wakeups
2008-03-19 04:27:53 +01:00
sched: cleanup old and rarely used 'debug' features.
2008-03-21 16:43:47 +01:00
sched: high-res preemption tick
2008-01-25 21:08:29 +01:00
sched: balance RT task resched only on runqueue
2008-03-07 16:43:00 +01:00
sched: clean up kernel/sched_stat.h
2007-11-28 15:52:56 +01:00
make seccomp zerocost in schedule
2007-07-16 09:05:50 -07:00
freezer vs stopped or traced
2008-03-04 07:59:54 -08:00
rcu: add support for dynamic ticks and preempt rcu
2008-02-29 18:46:50 +01:00
softlockup: fix task state setting
2008-02-29 18:46:53 +01:00
spinlock: lockbreak cleanup
2008-01-30 13:31:20 +01:00
make srcu_readers_active() static
2008-02-06 10:41:02 -08:00
[PATCH] lockdep: stacktrace subsystem, core
2006-07-03 15:27:02 -07:00
stopmachine: semaphore to mutex
2008-02-06 10:41:08 -08:00
Pidns: make full use of xxx_vnr() calls
2008-02-08 09:22:29 -08:00
timerfd: new timerfd API
2008-02-05 09:44:07 -08:00
sched: revert load_balance_monitor() changes
2008-03-04 17:54:06 +01:00
constify tables in kernel/sysctl_check.c
2008-02-08 09:22:31 -08:00
kernel/taskstats.c: fix bogus nlmsg_free()
2007-11-14 18:45:44 -08:00
kprobes: kretprobe user entry-handler
2008-02-06 10:41:11 -08:00
avoid overflows in kernel/time.c
2008-02-08 09:22:39 -08:00
timeconst.pl: correct reversal of USEC_TO_HZ and HZ_TO_USEC
2008-02-12 14:29:26 -08:00
NOHZ: reevaluate idle sleep length after add_timer_on()
2008-03-26 08:28:55 +01:00
Add scaled time to taskstats based process accounting
2007-10-18 14:37:28 -07:00
header cleaning: don't include smp_lock.h when not used
2007-05-08 11:15:07 -07:00
sched: rt-group: make rt groups scheduling configurable
2008-02-13 15:45:40 +01:00
namespaces: cleanup the code managed with the USER_NS option
2008-02-08 09:22:23 -08:00
Fix UTS corruption during clone(CLONE_NEWUTS)
2007-09-19 11:24:17 -07:00
Isolate the UTS namespace's domainname and hostname back
2007-11-29 09:24:53 -08:00
kernel: remove fastcall in kernel/*
2008-02-08 09:22:31 -08:00
workqueue: make delayed_work_timer_fn() static
2008-02-08 09:22:37 -08:00
6496968e6c