Fix kmemtrace printk warnings:
kernel/trace/kmemtrace.c:142: warning: format '%4ld' expects type 'long int', but argument 3 has type 'size_t'
kernel/trace/kmemtrace.c:147: warning: format '%4ld' expects type 'long int', but argument 3 has type 'size_t'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch brings various bugfixes:
- Drop the first irrelevant task switch on the very beginning of a trace.
- Drop the OVERHEAD word from the headers, the DURATION word is sufficient
and will not overlap other columns.
- Make the headers fit well their respective columns whatever the
selected options.
Ie, default options:
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
1) 0.646 us | }
1) | mem_cgroup_del_lru_list() {
1) 0.624 us | lookup_page_cgroup();
1) 1.970 us | }
echo funcgraph-proc > trace_options
# tracer: function_graph
#
# CPU TASK/PID DURATION FUNCTION CALLS
# | | | | | | | | |
0) bash-2937 | 0.895 us | }
0) bash-2937 | 0.888 us | __rcu_read_unlock();
0) bash-2937 | 0.864 us | conv_uni_to_pc();
0) bash-2937 | 1.015 us | __rcu_read_lock();
echo nofuncgraph-cpu > trace_options
echo nofuncgraph-proc > trace_options
# tracer: function_graph
#
# DURATION FUNCTION CALLS
# | | | | | |
3.752 us | native_pud_val();
0.616 us | native_pud_val();
0.624 us | native_pmd_val();
About features, one can now disable the duration (this will hide the
overhead too for convenient reasons and because on doesn't need
overhead if it hasn't the duration):
echo nofuncgraph-duration > trace_options
# tracer: function_graph
#
# FUNCTION CALLS
# | | | |
cap_vm_enough_memory() {
__vm_enough_memory() {
vm_acct_memory();
}
}
}
And at last, an option to print the absolute time:
//Restart from default options
echo funcgraph-abstime > trace_options
# tracer: function_graph
#
# TIME CPU DURATION FUNCTION CALLS
# | | | | | | | |
261.339774 | 1) + 42.823 us | }
261.339775 | 1) 1.045 us | _spin_lock_irq();
261.339777 | 1) 0.940 us | _spin_lock_irqsave();
261.339778 | 1) 0.752 us | _spin_unlock_irqrestore();
261.339780 | 1) 0.857 us | _spin_unlock_irq();
261.339782 | 1) | flush_to_ldisc() {
261.339783 | 1) | tty_ldisc_ref() {
261.339783 | 1) | tty_ldisc_try() {
261.339784 | 1) 1.075 us | _spin_lock_irqsave();
261.339786 | 1) 0.842 us | _spin_unlock_irqrestore();
261.339788 | 1) 4.211 us | }
261.339788 | 1) 5.662 us | }
The format is seconds.usecs.
I guess no one needs the nanosec precision here, the main goal is to have
an overview about the general timings of events, and to see the place when
the trace switches from one cpu to another.
ie:
274.874760 | 1) 0.676 us | _spin_unlock();
274.874762 | 1) 0.609 us | native_load_sp0();
274.874763 | 1) 0.602 us | native_load_tls();
274.878739 | 0) 0.722 us | }
274.878740 | 0) 0.714 us | native_pmd_val();
274.878741 | 0) 0.730 us | native_pmd_val();
Here there is a 4000 usecs difference when we switch the cpu.
Changes in V2:
- Completely fix the first pointless task switch.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix to preempt trace triggering lockdep check_flag failure
In local_bh_disable, the use of add_preempt_count causes the
preempt tracer to start recording the time preemption is off.
But because it already modified the preempt_count to show
softirqs disabled, and before it called the lockdep code to
handle this, it causes a state that lockdep can not handle.
The preempt tracer will reset the ring buffer on start of a trace,
and the ring buffer reset code does a spin_lock_irqsave. This
calls into lockdep and lockdep will fail when it detects the
invalid state of having softirqs disabled but the internal
current->softirqs_enabled is still set.
The fix is to manually add the SOFTIRQ_OFFSET to preempt count
and call the preempt tracer code outside the lockdep critical
area.
Thanks to Peter Zijlstra for suggesting this solution.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The logic in the tracing_start/stop code prevents the WARN_ON
from ever detecting if a start/stop pair was mismatched.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup of duplicate features
The trace output disables the ring buffer and prevents tracing to
occur. The code in irqsoff to do the same thing is no longer needed.
This patch removes it.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix bad times of recent resets
The ring buffer needs to reset its timestamps when reseting of the
buffer, otherwise the timestamps are stale and might be used to
calculate times in the buffer causing funny timestamps to appear.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: better data for wakeup tracer
This patch adds the wakeup and schedule calls that are used by
the scheduler tracer to make the wakeup tracer more readable.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add option to trace all tasks or just RT tasks
The current wakeup tracer only traces RT task wakeups. This is
fine for those interested in wake up timings of RT tasks, but
it is useless for those that are interested in the causes
of long wakeups for non RT tasks.
This patch creates a "wakeup_rt" to implement the tracing of just
RT tasks (as the current "wakeup" does). And makes "wakeup" now
trace all tasks as an average developer would expect.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If the ring buffer recording has been disabled. Do not let
swapping of ring buffers occur. Simply return -EAGAIN.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix to erased trace output
To try not to have the outputing of a trace interfere with the wakeup
tracer, it would disable tracing while the output was printing. But
if a trace had started when it was disabled, it can show a partial
trace. To try to solve this, on closing of the tracer, it would
clear the trace buffer.
The latency tracers (wakeup and irqsoff) have two buffers. One for
recording and one for holding the max trace that is printed. The
clearing of the trace above should only affect the recording buffer.
But for some reason it would move the erased trace to the print
buffer. Probably due to a race with the closing of the trace and
the saving ofhe max race.
The above is all pretty useless, and if the user does not want the
printing of the trace to be traced itself, then the user can manual
disable tracing. This patch removes all the code that tries to keep
the output of the tracer from modifying the trace.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: use percpu data instead of a global structure
Use:
static DEFINE_PER_CPU(struct workqueue_global_stats, all_workqueue_stat);
instead of allocating a global structure.
percpu data also works well on NUMA.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reset the ftrace buffer on close. Since we use cyclic buffers, the
trace is not contiguous, anyway.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Check CONFIG_FREEZER instead of CONFIG_PM because kprobe booster
depends on freeze_processes() and thaw_processes() when CONFIG_PREEMPT=y.
This fixes a linkage error which occurs when CONFIG_PREEMPT=y, CONFIG_PM=y
and CONFIG_FREEZER=n.
Reported-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Len Brown <len.brown@intel.com>
Freezer fails to compile if with the following configuration
settings:
CONFIG_CGROUPS=y
CONFIG_CGROUP_FREEZER=y
CONFIG_MODULES=y
CONFIG_FREEZER=y
CONFIG_PM=y
CONFIG_PM_SLEEP=n
Fix this by making process.o compilation depend on CONFIG_FREEZER.
Reported-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
Impact: trace max latencies on start of latency tracing
This patch sets the max latency to zero whenever one of the
irq variant tracers or the wakeup tracer is set to current tracer.
Most developers expect to see output when starting up a latency
tracer. But since the max_latency is already set to max, and
it takes a latency greater than max_latency to be recorded, there
is no trace. This is not the expected behavior and has even confused
myself.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clean up
After reorganizing the functions in trace.c and trace_function.c,
they no longer need to be in global context. This patch makes the
functions and one variable into static.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: less likely to interleave function and stack traces
This patch does replaces the separate stack trace on function with
a record function and stack trace together. This will switch between
the function only recording to a function and stack recording.
Also some whitespace fix ups as well.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
After adding the printf format checking for trace_seq_printf, several
warnings now show up. This patch cleans them up.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Andrew Morton suggested adding a printf checker to trace_seq_printf
since there are a number of users that have improper format arguments.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
