linux/kernel
Steven Rostedt 32464779a1 ftrace: fix dyn ftrace filter selection
Impact: clean up and fix for dyn ftrace filter selection

The previous logic of the dynamic ftrace selection of enabling
or disabling functions was complex and incorrect. This patch simplifies
the code and corrects the usage. This simplification also makes the
code more robust.

Here is the correct logic:

  Given a function that can be traced by dynamic ftrace:

  If the function is not to be traced, disable it if it was enabled.
  (this is if the function is in the set_ftrace_notrace file)

  (filter is on if there exists any functions in set_ftrace_filter file)

  If the filter is on, and we are enabling functions:
    If the function is in set_ftrace_filter, enable it if it is not
      already enabled.
    If the function is not in set_ftrace_filter, disable it if it is not
      already disabled.

  Otherwise, if the filter is off and we are enabling function tracing:
    Enable the function if it is not already enabled.

  Otherwise, if we are disabling function tracing:
    Disable the function if it is not already disabled.

This code now sets or clears the ENABLED flag in the record, and at the
end it will enable the function if the flag is set, or disable the function
if the flag is cleared.

The parameters for the function that does the above logic is also
simplified. Instead of passing in confusing "new" and "old" where
they might be swapped if the "enabled" flag is not set. The old logic
even had one of the above always NULL and had to be filled in. The new
logic simply passes in one parameter called "nop". A "call" is calculated
in the code, and at the end of the logic, when we know we need to either
disable or enable the function, we can then use the "nop" and "call"
properly.

This code is more robust than the previous version.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-19 00:19:47 -05:00
..
irq irq: make variable static 2008-10-22 07:37:17 +02:00
power PM_TEST_SUSPEND should depend on RTC_CLASS, not RTC_LIB 2008-11-01 12:40:38 -07:00
time nohz: disable tick_nohz_kick_tick() for now 2008-11-10 22:39:27 +01:00
trace ftrace: fix dyn ftrace filter selection 2008-11-19 00:19:47 -05:00
.gitignore
acct.c tty: Fix abusers of current->sighand->tty 2008-10-13 09:51:42 -07:00
audit.c [PATCH] Fix the bug of using AUDIT_STATUS_RATE_LIMIT when set fail, no error output. 2008-08-01 12:15:16 -04:00
audit.h [PATCH 1/2] audit: move extern declarations to audit.h 2008-04-28 06:28:04 -04:00
audit_tree.c Fix inotify watch removal/umount races 2008-11-15 12:26:44 -08:00
auditfilter.c Fix inotify watch removal/umount races 2008-11-15 12:26:44 -08:00
auditsc.c tty: Fix abusers of current->sighand->tty 2008-10-13 09:51:42 -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: Fix setting of PF_SUPERPRIV by __capable() 2008-08-14 22:59:43 +10:00
cgroup.c cgroups: fix invalid cgrp->dentry before cgroup has been completely removed 2008-11-06 15:41:19 -08:00
cgroup_debug.c cgroups: fix probable race with put_css_set[_taskexit] and find_css_set 2008-10-20 08:52:38 -07:00
cgroup_freezer.c freezer_cg: disable writing freezer.state of root cgroup 2008-11-12 17:17:16 -08:00
compat.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
configs.c kernel/configs.c: remove useless comments 2008-10-20 08:52:34 -07:00
cpu.c cpumask: introduce new API, without changing anything 2008-11-06 09:05:33 +01:00
cpuset.c cpuset: use seq_*mask_* to print masks 2008-10-20 08:52:39 -07:00
delayacct.c per-task-delay-accounting: update taskstats for memory reclaim delay 2008-07-25 10:53:47 -07:00
dma-coherent.c dma-coherent: export dma_[alloc|release]_from_coherent methods 2008-08-22 08:34:53 +02:00
dma.c kernel/dma.c: remove a CVS keyword 2008-10-16 11:21:30 -07:00
exec_domain.c proc: move /proc/execdomains to kernel/exec_domain.c 2008-10-23 14:30:41 +04:00
exit.c Move "exit_robust_list" into mm_release() 2008-11-15 10:20:36 -08:00
extable.c
fork.c Move "exit_robust_list" into mm_release() 2008-11-15 10:20:36 -08:00
freezer.c freezer_cg: use thaw_process() in unfreeze_cgroup() 2008-10-30 11:38:45 -07:00
futex.c hrtimer: make the futex() system call use the per process slack value 2008-09-11 07:17:00 -07:00
futex_compat.c
hrtimer.c hrtimer: clean up unused callback modes 2008-11-12 09:54:40 +01:00
itimer.c timers: fix itimer/many thread hang 2008-09-14 16:25:35 +02:00
kallsyms.c kernel/kallsyms.c: fix double return 2008-10-16 11:21:32 -07:00
Kconfig.freezer container freezer: implement freezer cgroup subsystem 2008-10-20 08:52:34 -07:00
Kconfig.hz sched: fix SCHED_HRTICK dependency 2008-07-28 14:37:38 +02:00
Kconfig.preempt
kexec.c kexec: fix crash_save_vmcoreinfo_init build problem 2008-10-20 15:28:50 -07:00
kfifo.c
kgdb.c kgdb: call touch_softlockup_watchdog on resume 2008-10-06 13:50:59 -05:00
kmod.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus 2008-10-16 12:38:34 -07:00
kprobes.c kernel/kprobes.c: don't pad kretprobe_table_locks[] on uniprocessor builds 2008-11-12 17:17:17 -08:00
ksysfs.c profiling: dynamically enable readprofile at runtime 2008-10-16 11:21:31 -07:00
kthread.c Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
latencytop.c kernel: use non-racy method for proc entries creation 2008-04-29 08:06:22 -07:00
lockdep.c lockdep: fix irqs on/off ip tracing 2008-10-28 11:19:07 +01:00
lockdep_internals.h lockdep: build fix 2008-08-13 12:55:10 +02:00
lockdep_proc.c lockstat: fix numerical output rounding error 2008-08-26 10:37:46 +02:00
Makefile Merge branch 'tracing/ftrace' into tracing/urgent 2008-10-22 09:08:14 +02:00
marker.c markers: bit-field is not thread-safe nor smp-safe 2008-10-14 10:38:45 +02:00
module.c Merge branch 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc 2008-10-23 12:04:37 -07:00
mutex-debug.c mutex-debug: check mutex magic before owner 2008-05-16 16:53:35 +02:00
mutex-debug.h
mutex.c locking: fix mutex @key parameter kernel-doc notation 2008-07-28 18:12:36 +02:00
mutex.h
notifier.c ftrace: ignore functions that cannot be kprobe-ed 2008-10-14 10:34:22 +02:00
ns_cgroup.c cgroup_clone: use pid of newly created task for new cgroup 2008-07-25 10:53:37 -07:00
nsproxy.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
panic.c Make panic= and panic_on_oops into core_params 2008-10-22 10:00:25 +11:00
params.c Fix compile warning in kernel/params.c 2008-10-23 12:09:00 -07:00
pid.c pidns: remove now unused find_pid function. 2008-07-25 10:53:45 -07:00
pid_namespace.c pid_ns: (BUG 11391) change ->child_reaper when init->group_leader exits 2008-09-02 19:21:38 -07:00
pm_qos_params.c pm_qos_requirement might sleep 2008-09-02 19:21:40 -07:00
posix-cpu-timers.c timers: fix itimer/many thread hang, v2 2008-09-23 13:38:44 +02:00
posix-timers.c Merge branch 'timers/range-hrtimers' into v28-range-hrtimers-for-linus-v2 2008-10-22 09:48:06 +02:00
printk.c printk: remove unused code from kernel/printk.c 2008-10-23 21:54:29 +02:00
profile.c kernel/profile: fix profile_init() section mismatch 2008-10-30 11:38:46 -07:00
ptrace.c make ptrace_untrace() static 2008-10-20 08:52:39 -07:00
rcuclassic.c rcu: RCU-based detection of stalled CPUs for Classic RCU, fix 2008-10-03 10:41:00 +02:00
rcupdate.c rcupdate: fix bug of rcu_barrier*() 2008-10-21 15:59:53 +02:00
rcupreempt.c byteorder: remove direct includes of linux/byteorder/swab[b].h 2008-10-20 08:52:40 -07:00
rcupreempt_trace.c rcu: trace fix possible mem-leak 2008-08-15 17:54:40 +02:00
rcutorture.c byteorder: remove direct includes of linux/byteorder/swab[b].h 2008-10-20 12:51:53 -07:00
relay.c relay: fix "full buffer with exactly full last subbuffer" accounting problem 2008-08-05 14:33:46 -07:00
res_counter.c cgroup files: convert res_counter_write() to be a cgroups write_string() handler 2008-07-25 10:53:36 -07:00
resource.c reserve_region_with_split: Fix GFP_KERNEL usage under spinlock 2008-11-01 09:53:58 -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 hrtimer: convert kernel/* to the new hrtimer apis 2008-09-05 21:35:13 -07:00
rtmutex.h
rtmutex_common.h
rwsem.c
sched.c sched: fix init_idle()'s use of sched_clock() 2008-11-12 20:05:50 +01:00
sched_clock.c sched_clock: prevent scd->clock from moving backwards 2008-10-10 11:17:04 +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: clean up debug info 2008-11-10 10:51:51 +01:00
sched_fair.c sched: release buddies on yield 2008-11-11 11:57:22 +01:00
sched_features.h sched: backward looking buddy 2008-11-05 10:30:14 +01:00
sched_idletask.c sched: add CONFIG_SMP consistency 2008-10-22 10:01:52 +02:00
sched_rt.c Merge commit 'v2.6.28-rc1' into sched/urgent 2008-10-24 12:48:46 +02:00
sched_stats.h Merge branch 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc 2008-10-23 12:04:37 -07:00
seccomp.c
semaphore.c semaphore: __down_common: use signal_pending_state() 2008-08-05 14:33:47 -07:00
signal.c 'kill sig -1' must only apply to caller's namespace 2008-10-30 11:38:46 -07:00
smp.c generic-ipi: fix the smp_mb() placement 2008-11-06 08:41:56 +01:00
softirq.c irq: call __irq_enter() before calling the tick_idle_check 2008-11-10 22:36:39 +01:00
softlockup.c Make the taint flags reliable 2008-10-16 11:21:31 -07:00
spinlock.c lockdep: spin_lock_nest_lock(), checkpatch fixes 2008-08-13 13:56:51 +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 Revert "Call init_workqueues before pre smp initcalls." 2008-10-25 19:53:38 -07:00
sys.c Merge branch 'timers/range-hrtimers' into v28-range-hrtimers-for-linus-v2 2008-10-22 09:48:06 +02:00
sys_ni.c Configure out AIO support 2008-10-16 11:21:51 -07:00
sysctl.c Merge commit 'v2.6.28-rc2' into tracing/urgent 2008-10-27 10:50:54 +01:00
sysctl_check.c sysctl: check for bogus modes 2008-07-25 10:53:45 -07:00
taskstats.c taskstats: remove initialization of static per-cpu variable 2008-07-25 10:53:47 -07:00
test_kprobes.c
time.c select: add a timespec_add_safe() function 2008-09-05 21:34:57 -07:00
timeconst.pl Make constants in kernel/timeconst.h fixed 64 bits 2008-05-02 16:18:42 -07:00
timer.c Add round_jiffies_up and related routines 2008-11-06 08:42:48 +01:00
tracepoint.c tracepoint: check if the probe has been registered 2008-10-27 16:45:46 +01:00
tsacct.c task IO accounting: move all IO statistics in struct task_io_accounting 2008-07-27 16:12:28 -07:00
uid16.c
user.c sched: rt-bandwidth for user grouping interface 2008-08-19 13:10:09 +02:00
user_namespace.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
utsname.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
utsname_sysctl.c sysctl: simplify ->strategy 2008-10-16 11:21:47 -07:00
wait.c wait: kill is_sync_wait() 2008-10-16 11:21:31 -07:00
workqueue.c cpumask: introduce new API, without changing anything 2008-11-06 09:05:33 +01:00