Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Srinivasa D S ef53d9c5e4 kprobes: improve kretprobe scalability with hashed locking ... Currently list of kretprobe instances are stored in kretprobe object (as used_instances,free_instances) and in kretprobe hash table. We have one global kretprobe lock to serialise the access to these lists. This causes only one kretprobe handler to execute at a time. Hence affects system performance, particularly on SMP systems and when return probe is set on lot of functions (like on all systemcalls). Solution proposed here gives fine-grain locks that performs better on SMP system compared to present kretprobe implementation. Solution: 1) Instead of having one global lock to protect kretprobe instances present in kretprobe object and kretprobe hash table. We will have two locks, one lock for protecting kretprobe hash table and another lock for kretporbe object. 2) We hold lock present in kretprobe object while we modify kretprobe instance in kretprobe object and we hold per-hash-list lock while modifying kretprobe instances present in that hash list. To prevent deadlock, we never grab a per-hash-list lock while holding a kretprobe lock. 3) We can remove used_instances from struct kretprobe, as we can track used instances of kretprobe instances using kretprobe hash table. Time duration for kernel compilation ("make -j 8") on a 8-way ppc64 system with return probes set on all systemcalls looks like this. cacheline non-cacheline Un-patched kernel aligned patch aligned patch =============================================================================== real 9m46.784s 9m54.412s 10m2.450s user 40m5.715s 40m7.142s 40m4.273s sys 2m57.754s 2m58.583s 3m17.430s =========================================================== Time duration for kernel compilation ("make -j 8) on the same system, when kernel is not probed. ========================= real 9m26.389s user 40m8.775s sys 2m7.283s ========================= Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com> Signed-off-by: Jim Keniston <jkenisto@us.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2008-07-25 10:53:30 -07:00
..
irq	kernel/irq/manage.c: replace a printk + WARN_ON() to a WARN()	2008-07-25 10:53:29 -07:00
power	pm: fix try_to_freeze_tasks()'s use of do_div()	2008-07-24 10:47:24 -07:00
time	Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-24 12:55:01 -07:00
trace	cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr	2008-07-18 22:02:57 +02:00
.gitignore
acct.c
audit.c	[PATCH] remove useless argument type in audit_filter_user()	2008-06-24 23:36:35 -04:00
audit.h
audit_tree.c	[PATCH] list_for_each_rcu must die: audit	2008-05-17 03:30:23 -04:00
auditfilter.c	[PATCH] remove useless argument type in audit_filter_user()	2008-06-24 23:36:35 -04:00
auditsc.c	x86_64 syscall audit fast-path	2008-07-23 17:47:32 -07:00
backtracetest.c	backtrace: replace timer with tasklet + completions	2008-06-27 18:09:16 +02:00
bounds.c	Add kbuild.h that contains common definitions for kbuild users	2008-04-29 08:06:29 -07:00
capability.c	security: filesystem capabilities refactor kernel code	2008-07-24 10:47:22 -07:00
cgroup.c	cgroups: remove node_ prefix_from ns subsystem	2008-05-24 09:56:14 -07:00
cgroup_debug.c
compat.c	ntp: support for TAI	2008-05-01 08:03:59 -07:00
configs.c	kernel: use non-racy method for proc entries creation	2008-04-29 08:06:22 -07:00
cpu.c	Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-23 19:36:53 -07:00
cpuset.c	Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-23 19:36:53 -07:00
delayacct.c
dma.c	kernel: use non-racy method for proc entries creation	2008-04-29 08:06:22 -07:00
exec_domain.c	remove CONFIG_KMOD from core kernel code	2008-07-22 19:24:31 +10:00
exit.c	fix dangling zombie when new parent ignores children	2008-07-16 18:02:34 -07:00
extable.c
fork.c	clean up duplicated alloc/free_thread_info	2008-07-25 10:53:28 -07:00
futex.c	futexes: fix fault handling in futex_lock_pi	2008-06-23 13:31:15 +02:00
futex_compat.c
hrtimer.c	Merge branch 'generic-ipi' into generic-ipi-for-linus	2008-07-15 21:55:59 +02:00
itimer.c
kallsyms.c	kallsyms: fix potential overflow in binary search	2008-07-25 10:53:27 -07:00
Kconfig.hz	sched: fix hrtick & generic-ipi dependency	2008-07-23 11:18:28 +02:00
Kconfig.preempt
kexec.c	kexec: make extended crashkernel= syntax less confusing	2008-05-01 08:04:00 -07:00
kfifo.c
kgdb.c	kgdb: sparse fix	2008-06-24 10:52:55 -05:00
kmod.c	call_usermodehelper(): increase reliability	2008-07-25 10:53:28 -07:00
kprobes.c	kprobes: improve kretprobe scalability with hashed locking	2008-07-25 10:53:30 -07:00
ksysfs.c
kthread.c	kthread: reduce stack pressure in create_kthread and kthreadd	2008-07-18 18:46:58 +02:00
latencytop.c	kernel: use non-racy method for proc entries creation	2008-04-29 08:06:22 -07:00
lockdep.c	Merge branch 'core/locking' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-14 14:55:13 -07:00
lockdep_internals.h	lockdep: add lock_class information to lock_chain and output it	2008-06-24 01:28:20 +02:00
lockdep_proc.c	lockdep: add lock_class information to lock_chain and output it	2008-06-24 01:28:20 +02:00
Makefile	build kernel/profile.o only when requested	2008-07-25 10:53:27 -07:00
marker.c	Markers - remove extra format argument	2008-05-23 22:25:27 +02:00
module.c	modules: Take a shortcut for checking if an address is in a module	2008-07-22 19:24:28 +10:00
mutex-debug.c	mutex-debug: check mutex magic before owner	2008-05-16 16:53:35 +02:00
mutex-debug.h
mutex.c	__mutex_lock_common: use signal_pending_state()	2008-06-10 11:45:09 +02:00
mutex.h
notifier.c	ipc: re-enable msgmni automatic recomputing msgmni if set to negative	2008-04-29 08:06:13 -07:00
ns_cgroup.c
nsproxy.c	ipc: sysvsem: refuse clone(CLONE_SYSVSEM|CLONE_NEWIPC)	2008-04-29 08:06:14 -07:00
panic.c	Add a WARN() macro; this is WARN_ON() + printk arguments	2008-07-25 10:53:29 -07:00
params.c
pid.c	rcu: split list.h and move rcu-protected lists into rculist.h	2008-05-19 10:01:37 +02:00
pid_namespace.c	pidns: make pid->level and pid_ns->level unsigned	2008-04-30 08:29:49 -07:00
pm_qos_params.c	pm_qos_params: BKL pushdown	2008-07-02 15:06:24 -06:00
posix-cpu-timers.c	posix-timers: print RT watchdog message	2008-05-24 18:49:22 +02:00
posix-timers.c	signals: join send_sigqueue() with send_group_sigqueue()	2008-04-30 08:29:36 -07:00
printk.c	printk ratelimiting rewrite	2008-07-25 10:53:29 -07:00
profile.c	build kernel/profile.o only when requested	2008-07-25 10:53:27 -07:00
ptrace.c	ptrace children revamp	2008-07-16 18:02:33 -07:00
rcuclassic.c	Merge branch 'linus' into cpus4096	2008-07-16 00:29:07 +02:00
rcupdate.c	Merge branch 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-15 14:12:03 -07:00
rcupreempt.c	Merge branch 'linus' into cpus4096	2008-07-16 00:29:07 +02:00
rcupreempt_trace.c	rcu: remove duplicated include in kernel/rcupreempt_trace.c	2008-05-19 10:03:39 +02:00
rcutorture.c	rcu: make rcutorture even more vicious: invoke RCU readers from irq handlers (timers)	2008-06-26 09:24:33 +02:00
relay.c	splice: fix sendfile() issue with relay	2008-05-28 14:49:27 +02:00
res_counter.c
resource.c	kernel: use non-racy method for proc entries creation	2008-04-29 08:06:22 -07:00
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c	sysdev: Pass the attribute to the low level sysdev show/store function	2008-07-21 21:55:02 -07:00
rtmutex.c
rtmutex.h
rtmutex_common.h
rwsem.c
sched.c	Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-23 19:36:53 -07:00
sched_clock.c	Merge branch 'sched/clock' into sched/devel	2008-07-14 12:19:13 +02:00
sched_cpupri.c	sched: use a 2-d bitmap for searching lowest-pri CPU	2008-06-06 15:19:28 +02:00
sched_cpupri.h	sched: fix the cpuprio count really	2008-06-06 15:19:44 +02:00
sched_debug.c	sched: add full schedstats to /proc/sched_debug	2008-06-27 14:31:31 +02:00
sched_fair.c	Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-23 19:36:53 -07:00
sched_features.h	sched: bias effective_load() error towards failing wake_affine().	2008-06-27 14:31:47 +02:00
sched_idletask.c	sched: make rt_sched_class, idle_sched_class static	2008-05-05 23:56:17 +02:00
sched_rt.c	Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-07-24 12:53:51 -07:00
sched_stats.h	sched: fix accounting in task delay accounting & migration	2008-07-04 12:50:23 +02:00
seccomp.c
semaphore.c	mmiotrace broken in linux-next (8-bit writes only)	2008-07-01 10:14:06 +02:00
signal.c	posix timers: discard SI_TIMER signals on exec	2008-05-26 10:37:07 -07:00
smp.c	generic ipi function calls: wait on alloc failure fallback	2008-07-15 14:12:20 -07:00
softirq.c	Merge branch 'linus' into timers/nohz	2008-07-18 19:53:16 +02:00
softlockup.c	softlockup: print a module list on being stuck	2008-07-05 08:51:24 +02:00
spinlock.c	ftrace: lockdep notrace annotations	2008-05-23 20:39:40 +02:00
srcu.c
stacktrace.c	stacktrace: fix modular build, export print_stack_trace and save_stack_trace	2008-06-30 09:20:55 +02:00
stop_machine.c	cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr	2008-07-18 22:02:57 +02:00
sys.c	call_usermodehelper(): increase reliability	2008-07-25 10:53:28 -07:00
sys_ni.c	flag parameters: fix compile error of sys_epoll_create1	2008-07-25 10:53:26 -07:00
sysctl.c	printk ratelimiting rewrite	2008-07-25 10:53:29 -07:00
sysctl_check.c
taskstats.c	core: use performance variant for_each_cpu_mask_nr	2008-05-23 18:35:12 +02:00
test_kprobes.c
time.c	Make constants in kernel/timeconst.h fixed 64 bits	2008-05-02 16:18:42 -07:00
timeconst.pl	Make constants in kernel/timeconst.h fixed 64 bits	2008-05-02 16:18:42 -07:00
timer.c	Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm	2008-07-14 16:06:58 -07:00
tsacct.c
uid16.c
user.c	alloc_uid: cleanup	2008-04-30 08:29:53 -07:00
user_namespace.c
utsname.c
utsname_sysctl.c
wait.c
workqueue.c	pm: introduce new interfaces schedule_work_on() and queue_work_on()	2008-07-24 10:47:23 -07:00