Steven Rostedt (Red Hat) fef5aeeee9 ftrace: Replace tramp_hash with old_*_hash to save space ... Allowing function callbacks to declare their own trampolines requires that each ftrace_ops that has a trampoline must have some sort of accounting that keeps track of which ops has a trampoline attached to a record. The easy way to solve this was to add a "tramp_hash" that created a hash entry for every function that a ops uses with a trampoline. But since we can have literally tens of thousands of functions being traced, that means we need tens of thousands of descriptors to map the ops to the function in the hash. This is quite expensive and can cause enabling and disabling the function graph tracer to take some time to start and stop. It can take up to several seconds to disable or enable all functions in the function graph tracer for this reason. The better approach albeit more complex, is to keep track of how ops are being enabled and disabled, and use that along with the counting of the number of ops attached to records, to determive what ops has a trampoline attached to a record at enabling and disabling of tracing. To do this, the tramp_hash has been replaced with an old_filter_hash and old_notrace_hash, which get the copy of the ops filter_hash and notrace_hash respectively. The old hashes is kept until the ops has been modified or removed and the old hashes are used with the logic of the accounting to determine the ops that have the trampoline of a record. The reason this has less of a footprint is due to the trick that an "empty" hash in the filter_hash means "all functions" and an empty hash in the notrace hash means "no functions" in the hash. This is much more efficienct, doesn't have the delay, and takes up much less memory, as we do not need to map all the functions but just figure out which functions are mapped at the time it is enabled or disabled. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>		2014-09-10 10:48:45 -04:00
..
bpf	net: filter: split 'struct sk_filter' into socket and bpf parts	2014-08-02 15:03:58 -07:00
debug	kdb: Use ktime_get_ts()	2014-06-12 16:18:45 +02:00
events	Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-08-24 16:16:55 -07:00
gcov	kernel/gcov/fs.c: remove unnecessary null test before debugfs_remove	2014-08-08 15:57:24 -07:00
irq	irq: Export handle_fasteoi_irq	2014-08-25 21:13:30 +02:00
locking	arch, locking: Ciao arch_mutex_cpu_relax()	2014-07-17 12:32:47 +02:00
power	PM / sleep: Fix test_suspend= command line option	2014-09-03 01:21:03 +02:00
printk	printk: Add function to return log buffer address and size	2014-08-13 15:13:44 +10:00
rcu	rcu: Make nocb leader kthreads process pending callbacks after spawning	2014-08-28 05:59:59 -07:00
sched	Merge branches 'pm-sleep', 'pm-cpufreq' and 'pm-cpuidle'	2014-08-11 23:19:48 +02:00
time	timekeeping: Update timekeeper before updating vsyscall and pvclock	2014-09-06 12:58:18 +02:00
trace	ftrace: Replace tramp_hash with old_*_hash to save space	2014-09-10 10:48:45 -04:00
.gitignore
acct.c	kernel/acct.c: fix coding style warnings and errors	2014-08-08 15:57:27 -07:00
async.c
audit_tree.c	inotify: Fix reporting of cookies for inotify events	2014-02-18 11:17:17 +01:00
audit_watch.c	inotify: Fix reporting of cookies for inotify events	2014-02-18 11:17:17 +01:00
audit.c	CAPABILITIES: remove undefined caps from all processes	2014-07-24 21:53:47 +10:00
audit.h	audit: Use struct net not pid_t to remember the network namespce to reply in	2014-03-20 10:10:53 -04:00
auditfilter.c	kernel/auditfilter.c: replace count*size kmalloc by kcalloc	2014-08-06 18:01:12 -07:00
auditsc.c	auditsc: audit_krule mask accesses need bounds checking	2014-06-10 08:44:40 -07:00
backtracetest.c	kernel/backtracetest.c: replace no level printk by pr_info()	2014-06-04 16:54:14 -07:00
bounds.c	page-cgroup: get rid of NR_PCG_FLAGS	2014-08-08 15:57:18 -07:00
capability.c	CAPABILITIES: remove undefined caps from all processes	2014-07-24 21:53:47 +10:00
cgroup_freezer.c	cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes	2014-07-15 11:05:09 -04:00
cgroup.c	Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2014-08-04 10:11:28 -07:00
compat.c	compat: nanosleep: Clarify error handling	2014-09-06 12:58:18 +02:00
configs.c
context_tracking.c	x86/kprobes: Fix build errors and blacklist context_track_user	2014-06-14 09:07:44 +02:00
cpu_pm.c
cpu.c	sched: Rework check_for_tasks()	2014-07-05 11:17:45 +02:00
cpuset.c	Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2014-08-04 10:11:28 -07:00
crash_dump.c
cred.c
delayacct.c	delayacct: Remove braindamaged type conversions	2014-07-23 10:18:06 -07:00
dma.c
elfcore.c
exec_domain.c	kernel/exec_domain.c: code clean-up	2014-06-04 16:54:15 -07:00
exit.c	kernel/exit.c: fix coding style warnings and errors	2014-08-08 15:57:22 -07:00
extable.c	asmlinkage: Make main_extable_sort_needed visible	2014-02-13 18:13:22 -08:00
fork.c	seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock	2014-08-11 13:29:12 -07:00
freezer.c
futex_compat.c	compat: Get rid of (get|put)_compat_time(val|spec)	2014-02-02 14:09:12 -08:00
futex.c	futex: Simplify futex_lock_pi_atomic() and make it more robust	2014-06-21 22:26:24 +02:00
groups.c	kernel/groups.c: remove return value of set_groups	2014-04-03 16:21:05 -07:00
hung_task.c	kernel/hung_task.c: convert simple_strtoul to kstrtouint	2014-06-04 16:54:15 -07:00
irq_work.c	irq_work: Remove BUG_ON in irq_work_run()	2014-07-05 11:17:26 +02:00
jump_label.c
kallsyms.c	kernel/kallsyms.c: fix %pB when there's no symbol at the address	2014-08-08 15:57:18 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks	locking/rwsem: Add CONFIG_RWSEM_SPIN_ON_OWNER	2014-07-16 14:57:13 +02:00
Kconfig.preempt
kexec.c	kexec: create a new config option CONFIG_KEXEC_FILE for new syscall	2014-08-29 16:28:16 -07:00
kmod.c	signals: change wait_for_helper() to use kernel_sigaction()	2014-06-06 16:08:12 -07:00
kprobes.c	kprobes: Skip kretprobe hit in NMI context to avoid deadlock	2014-08-08 10:38:04 +02:00
ksysfs.c	kobject: Make support for uevent_helper optional.	2014-04-25 12:00:49 -07:00
kthread.c	kthread_work: wake up worker only when the worker is idle	2014-07-28 14:07:52 -04:00
latencytop.c	kernel/latencytop.c: convert seq_printf to seq_puts	2014-06-04 16:54:15 -07:00
Makefile	bin2c: move bin2c in scripts/basic	2014-08-08 15:57:32 -07:00
module_signing.c
module-internal.h
module.c	module: Clean up ro/nx after early module load failures	2014-08-16 04:47:00 +09:30
notifier.c	kprobes, notifier: Use NOKPROBE_SYMBOL macro in notifier	2014-04-24 10:26:39 +02:00
nsproxy.c	namespaces: Use task_lock and not rcu to protect nsproxy	2014-07-29 18:08:50 -07:00
padata.c
panic.c	panic: add TAINT_SOFTLOCKUP	2014-08-08 15:57:24 -07:00
params.c	Add module param type 'ullong'	2014-07-17 22:07:37 +02:00
pid_namespace.c	pid_namespace: pidns_get() should check task_active_pid_ns() != NULL	2014-04-02 16:20:21 -07:00
pid.c
profile.c	kernel/profile.c: use static const char instead of static char	2014-06-06 16:08:13 -07:00
ptrace.c	sched: Remove proliferation of wait_on_bit() action functions	2014-07-16 15:10:39 +02:00
range.c
reboot.c	kernel/reboot.c: convert simple_strtoul to kstrtoint	2014-06-04 16:54:15 -07:00
relay.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2014-04-12 14:49:50 -07:00
res_counter.c	kernel/res_counter.c: replace simple_strtoull by kstrtoull	2014-06-04 16:54:15 -07:00
resource.c	resource: fix the case of null pointer access	2014-08-29 16:28:15 -07:00
seccomp.c	seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock	2014-08-11 13:29:12 -07:00
signal.c	Merge branch 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc	2014-08-09 09:58:12 -07:00
smp.c	kernel/smp.c:on_each_cpu_cond(): fix warning in fallback path	2014-08-06 18:01:22 -07:00
smpboot.c
smpboot.h
softirq.c	Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu	2014-05-22 11:36:10 +02:00
stacktrace.c
stop_machine.c	kernel/stop_machine.c: kernel-doc warning fix	2014-06-04 16:54:15 -07:00
sys_ni.c	kexec: new syscall kexec_file_load() declaration	2014-08-08 15:57:32 -07:00
sys.c	sched: move no_new_privs into new atomic flags	2014-07-18 12:13:38 -07:00
sysctl_binary.c	ipv6: Allow accepting RA from local IP addresses.	2014-07-01 12:16:24 -07:00
sysctl.c	mm, hugetlb: remove hugetlb_zero and hugetlb_infinity	2014-08-06 18:01:19 -07:00
system_certificates.S
system_keyring.c	KEYS: validate certificate trust only with builtin keys	2014-07-17 09:35:17 -04:00
task_work.c
taskstats.c
test_kprobes.c	kernel/test_kprobes.c: use current logging functions	2014-08-08 15:57:18 -07:00
torture.c	torture: Avoid format string leak to thead name	2014-07-07 10:12:56 -07:00
tracepoint.c	tracing: syscall_regfunc() should not skip kernel threads	2014-06-21 00:15:26 -04:00
tsacct.c	sched: Make task->start_time nanoseconds based	2014-07-23 10:18:05 -07:00
uid16.c
up.c	smp: Rename __smp_call_function_single() to smp_call_function_single_async()	2014-02-24 14:47:15 -08:00
user_namespace.c	proc: constify seq_operations	2014-08-08 15:57:22 -07:00
user-return-notifier.c
user.c	kernel/user.c: drop unused field 'files' from user_struct	2014-06-04 16:54:16 -07:00
utsname_sysctl.c	sysctl: convert use of typedef ctl_table to struct ctl_table	2014-06-06 16:08:16 -07:00
utsname.c	namespaces: Use task_lock and not rcu to protect nsproxy	2014-07-29 18:08:50 -07:00
watchdog.c	panic: add TAINT_SOFTLOCKUP	2014-08-08 15:57:24 -07:00
workqueue_internal.h	workqueue: rename manager_mutex to attach_mutex	2014-05-20 10:59:32 -04:00
workqueue.c	Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-08-04 10:09:27 -07:00