Impact: cleanup, no functionality changed
Change ntp_update_frequency() from a hard to follow code
flow that uses global variables as temporaries, to a clean
input+output flow.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, no functionality changed
There's an ugly u64 typecase in the MAX_TICKADJ_SCALED definition,
this can be eliminated by making the MAX_TICKADJ constant's type
64-bit (signed).
kernel/time/ntp.o:
text data bss dec hex filename
2504 114 136 2754 ac2 ntp.o.before
2504 114 136 2754 ac2 ntp.o.after
md5:
41f3009debc9b397d7394dd77d912f0a ntp.o.before.asm
41f3009debc9b397d7394dd77d912f0a ntp.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, no functionality changed
Instead of a hierarchy of conditions, transform them to clean
gradual conditions and return's.
This makes the flow easier to read and makes the purpose of
the function easier to understand.
kernel/time/ntp.o:
text data bss dec hex filename
2552 170 168 2890 b4a ntp.o.before
2552 170 168 2890 b4a ntp.o.after
md5:
eae1275df0b7d6290c13f6f6f8f05c8c ntp.o.before.asm
eae1275df0b7d6290c13f6f6f8f05c8c ntp.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, no functionality changed
Make this file a bit more readable by applying a consistent coding style.
No code changed:
kernel/time/ntp.o:
text data bss dec hex filename
2552 170 168 2890 b4a ntp.o.before
2552 170 168 2890 b4a ntp.o.after
md5:
eae1275df0b7d6290c13f6f6f8f05c8c ntp.o.before.asm
eae1275df0b7d6290c13f6f6f8f05c8c ntp.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Andrew pointed out that there's some small amount of
style rot in kernel/smp.c.
Clean it up.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Oleg noticed that we don't strictly need CSD_FLAG_WAIT, rework
the code so that we can use CSD_FLAG_LOCK for both purposes.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove the use of kmalloc() from the smp_call_function_*()
calls.
Steven's generic-ipi patch (d7240b98: generic-ipi: use per cpu
data for single cpu ipi calls) started the discussion on the use
of kmalloc() in this code and fixed the
smp_call_function_single(.wait=0) fallback case.
In this patch we complete this by also providing means for the
_many() call, which fully removes the need for kmalloc() in this
code.
The problem with the _many() call is that other cpus might still
be observing our entry when we're done with it. It solved this
by dynamically allocating data elements and RCU-freeing it.
We solve it by using a single per-cpu entry which provides
static storage and solves one half of the problem (avoiding
referencing freed data).
The other half, ensuring the queue iteration it still possible,
is done by placing re-used entries at the head of the list. This
means that if someone was still iterating that entry when it got
moved, he will now re-visit the entries on the list he had
already seen, but avoids skipping over entries like would have
happened had we placed the new entry at the end.
Furthermore, visiting entries twice is not a problem, since we
remove our cpu from the entry's cpumask once its called.
Many thanks to Oleg for his suggestions and him poking holes in
my earlier attempts.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that several per-cpu files can be read or spliced at the
same, we want the read/splice callbacks for tracing files to be
reentrants.
Until now, a single global mutex (trace_types_lock) serialized
the access to tracing_read_pipe(), tracing_splice_read_pipe(),
and the seq helpers.
Ie: it means that if a user tries to read trace_pipe0 and
trace_pipe1 at the same time, the access to the function
tracing_read_pipe() is contended and one reader must wait for
the other to finish its read call.
The trace_type_lock mutex is mostly here to serialize the access
to the global current tracer (current_trace), which can be
changed concurrently. Although the iter struct keeps a private
pointer to this tracer, its callbacks can be changed by another
function.
The method used here is to not keep anymore private reference to
the tracer inside the iterator but to make a copy of it inside
the iterator. Then it checks on subsequents read calls if the
tracer has changed. This is not costly because the current
tracer is not expected to be changed often, so we use a branch
prediction for that.
Moreover, we add a private mutex to the iterator (there is one
iterator per file descriptor) to serialize the accesses in case
of multiple consumers per file descriptor (which would be a
silly idea from the user). Note that this is not to protect the
ring buffer, since the ring buffer already serializes the
readers accesses. This is to prevent from traces weirdness in
case of concurrent consumers. But these mutexes can be dropped
anyway, that would not result in any crash. Just tell me what
you think about it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: split up tracing output per cpu
Currently, on the tracing debugfs directory, three files are
available to the user to let him extracting the trace output:
- trace is an iterator through the ring-buffer. It's a reader
but not a consumer It doesn't block when no more traces are
available.
- trace pretty similar to the former, except that it adds more
informations such as prempt count, irq flag, ...
- trace_pipe is a reader and a consumer, it will also block
waiting for traces if necessary (heh, yes it's a pipe).
The traces coming from different cpus are curretly mixed up
inside these files. Sometimes it messes up the informations,
sometimes it's useful, depending on what does the tracer
capture.
The tracing_cpumask file is useful to filter the output and
select only the traces captured a custom defined set of cpus.
But still it is not enough powerful to extract at the same time
one trace buffer per cpu.
So this patch creates a new directory: /debug/tracing/per_cpu/.
Inside this directory, you will now find one trace_pipe file and
one trace file per cpu.
Which means if you have two cpus, you will have:
trace0
trace1
trace_pipe0
trace_pipe1
And of course, reading these files will have the same effect
than with the usual tracing files, except that you will only see
the traces from the given cpu.
The original all-in-one cpu trace file are still available on
their original place.
Until now, only one consumer was allowed on trace_pipe to avoid
racy consuming on the ring-buffer. Now the approach changed a
bit, you can have only one consumer per cpu.
Which means you are allowed to read concurrently trace_pipe0 and
trace_pipe1 But you can't have two readers on trace_pipe0 or
trace_pipe1.
Following the same logic, if there is one reader on the common
trace_pipe, you can not have at the same time another reader on
trace_pipe0 or in trace_pipe1. Because in trace_pipe is already
a consumer in all cpu buffers in essence.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Simplify the barriers in generic remote function call interrupt
code.
Firstly, just unconditionally take the lock and check the list
in the generic_call_function_single_interrupt IPI handler. As
we've just taken an IPI here, the chances are fairly high that
there will be work on the list for us, so do the locking
unconditionally. This removes the tricky lockless list_empty
check and dubious barriers. The change looks bigger than it is
because it is just removing an outer loop.
Secondly, clarify architecture specific IPI locking rules.
Generic code has no tools to impose any sane ordering on IPIs if
they go outside normal cache coherency, ergo the arch code must
make them appear to obey cache coherency as a "memory operation"
to initiate an IPI, and a "memory operation" to receive one.
This way at least they can be reasoned about in generic code,
and smp_mb used to provide ordering.
The combination of these two changes means that explict barriers
can be taken out of queue handling for the single case -- shared
data is explicitly locked, and ipi ordering must conform to
that, so no barriers needed. An extra barrier is needed in the
many handler, so as to ensure we load the list element after the
IPI is received.
Does any architecture actually *need* these barriers? For the
initiator I could see it, but for the handler I would be
surprised. So the other thing we could do for simplicity is just
to require that, rather than just matching with cache coherency,
we just require a full barrier before generating an IPI, and
after receiving an IPI. In which case, the smp_mb()s can go
away. But just for now, we'll be on the safe side and use the
barriers (they're in the slow case anyway).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-arch@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: remove old debug/tracing API
/debug/tracing/latency_trace is an old legacy format we kept from
the old latency tracer. Remove the file for now. If there's any
useful bit missing then we'll propagate any useful output bits into
the /debug/tracing/trace output.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix CPU hotplug lockup
bts_hotcpu_handler() is called with irqs disabled, so using mutex_lock()
is a no-no.
All the BTS codepaths here are atomic (they do not schedule), so using
a spinlock is the right solution.
Cc: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds the directory /debug/tracing/events/ that will contain
all the registered trace points.
# ls /debug/tracing/events/
sched_kthread_stop sched_process_fork sched_switch
sched_kthread_stop_ret sched_process_free sched_wait_task
sched_migrate_task sched_process_wait sched_wakeup
sched_process_exit sched_signal_send sched_wakeup_new
# ls /debug/tracing/events/sched_switch/
enable
# cat /debug/tracing/events/sched_switch/enable
1
# cat /debug/tracing/set_event
sched_switch
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This patch changes the trace/sched.h to use the DECLARE_TRACE_FMT
such that they are automatically registered with the event tracer.
And it also adds the tracing sched headers to kernel/trace/events.c
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This patch creates the event tracing infrastructure of ftrace.
It will create the files:
/debug/tracing/available_events
/debug/tracing/set_event
The available_events will list the trace points that have been
registered with the event tracer.
set_events will allow the user to enable or disable an event hook.
example:
# echo sched_wakeup > /debug/tracing/set_event
Will enable the sched_wakeup event (if it is registered).
# echo "!sched_wakeup" >> /debug/tracing/set_event
Will disable the sched_wakeup event (and only that event).
# echo > /debug/tracing/set_event
Will disable all events (notice the '>')
# cat /debug/tracing/available_events > /debug/tracing/set_event
Will enable all registered event hooks.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Fix an invalid memory reference problem when cpu hotplug support is
disabled and the hw-branch-tracer is set as current tracer.
Initializing the tracer calls bts_trace_init() which has already
been freed at this time.
Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move the sysdev_suspend/resume from the callee to the callers, with
no real change in semantics, so that we can rework the disabling of
interrupts during suspend/hibernation.
This is based on an earlier patch from Linus.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes a race where a thread acquires the console while the
console is suspended, and the console is resumed before this
thread releases it. In this case, the secondary console
semaphore would be left locked, and the primary semaphore would
be released twice. This in turn would cause the console switch
on suspend or resume to hang forever.
Note that suspend_console does not actually lock the console
for clients that use acquire_console_sem, it only locks it for
clients that use try_acquire_console_sem. If we change
suspend_console to fully lock the console, then the kernel
may deadlock on suspend. One client of try_acquire_console_sem
is acquire_console_semaphore_for_printk, which uses it to
prevent printk from using the console while it is suspended.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoids later waking up to a blinking cursor if the device woke up and
returned to sleep before the console switch happened.
Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Snapshot device is opened with O_RDONLY during suspend and O_WRONLY durig
resume. Make sure we also call notifiers with correct parameter telling
them what we are really doing.
Signed-off-by: Andrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <gregkh@suse.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compilation of kprobes.c with CONFIG_PM unset is broken due to some broken
config dependncies. Fix that.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <gregkh@suse.de>
Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
the resume code does not currently wait for device probing to finish.
Even without async function calls this is dicey and not correct,
but with async function calls during the boot sequence this is going
to get hit more...
This patch adds the synchronization using the newly introduced helper.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Greg KH <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: added precaution on failure detection
Break out of the modifying loop as soon as a failure is detected.
This is just an added precaution found by code review and was not
found by any bug chasing.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This patch creates the weak functions: ftrace_arch_code_modify_prepare
and ftrace_arch_code_modify_post_process that are called before and
after the stop machine is called to modify the kernel text.
If the arch needs to do pre or post processing, it only needs to define
these functions.
[ Update: Ingo Molnar suggested using the name ftrace_arch_code_modify_*
over using ftrace_arch_modify_* ]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: trace only functions matching a pattern
The set_graph_function file let one to trace only one or several
chosen functions and follow all their code flow.
Currently, only a constant function name is allowed so this patch
allows the ftrace_regex functions:
- matches all functions that end with "name":
echo *name > set_graph_function
- matches all functions that begin with "name":
echo name* > set_graph_function
- matches all functions that contains "name":
echo *name* > set_graph_function
Example:
echo mutex* > set_graph_function
0) | mutex_lock_nested() {
0) 0.563 us | __might_sleep();
0) 2.072 us | }
0) | mutex_unlock() {
0) 1.036 us | __mutex_unlock_slowpath();
0) 2.433 us | }
0) | mutex_unlock() {
0) 0.691 us | __mutex_unlock_slowpath();
0) 1.787 us | }
0) | mutex_lock_interruptible_nested() {
0) 0.548 us | __might_sleep();
0) 1.945 us | }
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new scalable dynamic percpu allocator which allows dynamic
percpu areas to be accessed the same way as static ones
Implement scalable dynamic percpu allocator which can be used for both
static and dynamic percpu areas. This will allow static and dynamic
areas to share faster direct access methods. This feature is optional
and enabled only when CONFIG_HAVE_DYNAMIC_PER_CPU_AREA is defined by
arch. Please read comment on top of mm/percpu.c for details.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Impact: cleanup
There are two allocated per-cpu accessor macros with almost identical
spelling. The original and far more popular is per_cpu_ptr (44
files), so change over the other 4 files.
tj: kill percpu_ptr() and update UP too
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: mingo@redhat.com
Cc: lenb@kernel.org
Cc: cpufreq@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Since the GENERIC_TIME changes landed, the adjtimex behavior changed
for struct timex.tick and .freq changed. When the tick or freq value
is set, we adjust the tick_length_base in ntp_update_frequency().
However, this new value doesn't get applied to tick_length until the
next second (via second_overflow).
This means some applications that do quick time tweaking do not see the
requested change made as quickly as expected.
I've run a few tests with this change, and ntpd still functions fine.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: prevent deadlock if ring buffer gets corrupted
This patch adds a paranoid check to make sure the ring buffer consumer
does not go into an infinite loop. Since the ring buffer has been set
to read only, the consumer should not loop for more than the ring buffer
size. A check is added to make sure the consumer does not loop more than
the ring buffer size.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: fix output of function tracer to be useful
The function tracer is pretty useless if KALLSYMS is not configured.
Unless you are good at reading hex values, the function tracer should
select the KALLSYMS configuration.
Also, the dynamic function tracer will fail its self test if KALLSYMS
is not selected.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: fix to prevent hard lockup on self tests
If one of the tracers are broken and is constantly filling the ring
buffer while the test of the ring buffer is running, it will hang
the box. The reason is that the test is a consumer that will not
stop till the ring buffer is empty. But if the tracer is broken and
is constantly producing input to the buffer, this test will never
end. The result is a lockup of the box.
This happened when KALLSYMS was not defined and the dynamic ftrace
test constantly filled the ring buffer, because the filter failed
and all functions were being traced. Something was being called
that constantly filled the buffer.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Compilation of kprobes.c with CONFIG_PM unset is broken due to some broken
config dependncies. Fix that.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In cgroup_kill_sb(), root is freed before sb is detached from the list, so
another sget() may find this sb and call cgroup_test_super(), which will
access the root that has been freed.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is nothing really arch specific of the push and pop functions
used by the function graph tracer. This patch moves them to generic
code.
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: new timer API
Based on an idea from Martin Josefsson with the help of
Patrick McHardy and Stephen Hemminger:
introduce the mod_timer_pending() API which is a mod_timer()
offspring that is an invariant on already removed timers.
(regular mod_timer() re-activates non-pending timers.)
This is useful for the networking code in that it can
allow unserialized mod_timer_pending() timer-forwarding
calls, but a single del_timer*() will stop the timer
from being reactivated again.
Also while at it:
- optimize the regular mod_timer() path some more, the
timer-stat and a debug check was needlessly duplicated
in __mod_timer().
- make the exports come straight after the function, as
most other exports in timer.c already did.
- eliminate __mod_timer() as an external API, change the
users to mod_timer().
The regular mod_timer() code path is not impacted
significantly, due to inlining optimizations and due to
the simplifications.
Based-on-patch-from: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Cc: netdev@vger.kernel.org
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We can't OR shift values, so get rid of BIO_RW_SYNC and use BIO_RW_SYNCIO
and BIO_RW_UNPLUG explicitly. This brings back the behaviour from before
213d9417fe.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Impact: api and pipe waiting change
Currently, the waiting used in tracing_read_pipe() is done through a
100 msecs schedule_timeout() loop which periodically check if there
are traces on the buffer.
This can cause small latencies for programs which are reading the incoming
events.
This patch makes the reader waiting for the trace_wait waitqueue except
for few tracers such as the sched and functions tracers which might be
already hold the runqueue lock while waking up the reader.
This is performed through a new callback wait_pipe() on struct tracer.
If none is implemented on a specific tracer, the default waiting for
trace_wait queue is attached.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
'p' stands for pointer - make it clear in setup_irq() and free_irq()
what kind of pointer it is.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Linus noticed that the 'pp' variable can be eliminated
altogether, and the loop can be cleaned up further.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clean up
The traceon and traceoff function probes are confusing to developers
to what happens when a counter is not specified. This should help
clear things up.
# echo "*:traceoff" > set_ftrace_filter
# cat /debug/tracing/set_ftrace_filter
#### all functions enabled ####
do_fork:traceoff:unlimited
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: cleanup
Fix incorrect hint message in code and typos in comments.
Signed-off-by: Wenji Huang <wenji.huang@oracle.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This patch is to fix the return value of trace_selftest_startup_sysprof
and trace_selftest_startup_branch on failure.
Signed-off-by: Wenji Huang <wenji.huang@oracle.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Pass tsk to tracing_record_cmdline instead of current.
Signed-off-by: Wenji Huang <wenji.huang@oracle.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: clean up
Ingo Molnar did not like the _hook naming convention used by the
select function tracer. Luis Claudio R. Goncalves suggested using
the "_probe" extension. This patch implements the change of
calling the functions and variables "_hook" and replacing them
with "_probe".
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Ingo Molnar