linux-toradex.git/include/linux/trace_events.h, branch v4.6-rc3

Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2016-03-24T17:52:25+00:00

Pull tracing updates from Steven Rostedt:
 "Nothing major this round.  Mostly small clean ups and fixes.

  Some visible changes:

   - A new flag was added to distinguish traces done in NMI context.

   - Preempt tracer now shows functions where preemption is disabled but
     interrupts are still enabled.

  Other notes:

   - Updates were done to function tracing to allow better performance
     with perf.

   - Infrastructure code has been added to allow for a new histogram
     feature for recording live trace event histograms that can be
     configured by simple user commands.  The feature itself was just
     finished, but needs a round in linux-next before being pulled.

     This only includes some infrastructure changes that will be needed"

* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
  tracing: Record and show NMI state
  tracing: Fix trace_printk() to print when not using bprintk()
  tracing: Remove redundant reset per-CPU buff in irqsoff tracer
  x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
  tracing: Fix crash from reading trace_pipe with sendfile
  tracing: Have preempt(irqs)off trace preempt disabled functions
  tracing: Fix return while holding a lock in register_tracer()
  ftrace: Use kasprintf() in ftrace_profile_tracefs()
  ftrace: Update dynamic ftrace calls only if necessary
  ftrace: Make ftrace_hash_rec_enable return update bool
  tracing: Fix typoes in code comment and printk in trace_nop.c
  tracing, writeback: Replace cgroup path to cgroup ino
  tracing: Use flags instead of bool in trigger structure
  tracing: Add an unreg_all() callback to trigger commands
  tracing: Add needs_rec flag to event triggers
  tracing: Add a per-event-trigger 'paused' field
  tracing: Add get_syscall_name()
  tracing: Add event record param to trigger_ops.func()
  tracing: Make event trigger functions available
  tracing: Make ftrace_event_field checking functions available
  ...

tracepoints: move trace_print_flags definitions to tracepoint-defs.h

2016-03-15T23:55:16+00:00

The following patch will need to declare array of struct
trace_print_flags in a header.  To prevent this header from pulling in
all of RCU through trace_events.h, move the struct
trace_print_flags{_64} definitions to the new lightweight
tracepoint-defs.h header.

Signed-off-by: Vlastimil Babka 
Acked-by: David Rientjes 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Ingo Molnar 
Cc: Rasmus Villemoes 
Cc: Joonsoo Kim 
Cc: Minchan Kim 
Cc: Sasha Levin 
Cc: "Kirill A. Shutemov" 
Cc: Mel Gorman 
Cc: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

tracing: Add event record param to trigger_ops.func()

2016-03-08T16:19:31+00:00

Some triggers may need access to the trace event, so pass it in.  Also
fix up the existing trigger funcs and their callers.

Link: http://lkml.kernel.org/r/543e31e9fc445ef61077421ab219033401c39846.1449767187.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi 
Tested-by: Masami Hiramatsu 
Reviewed-by: Namhyung Kim 
Signed-off-by: Steven Rostedt

tracing: Do not have 'comm' filter override event 'comm' field

2016-03-04T14:57:10+00:00

Commit 9f61668073a8d "tracing: Allow triggers to filter for CPU ids and
process names" added a 'comm' filter that will filter events based on the
current tasks struct 'comm'. But this now hides the ability to filter events
that have a 'comm' field too. For example, sched_migrate_task trace event.
That has a 'comm' field of the task to be migrated.

 echo 'comm == "bash"' > events/sched_migrate_task/filter

will now filter all sched_migrate_task events for tasks named "bash" that
migrates other tasks (in interrupt context), instead of seeing when "bash"
itself gets migrated.

This fix requires a couple of changes.

1) Change the look up order for filter predicates to look at the events
   fields before looking at the generic filters.

2) Instead of basing the filter function off of the "comm" name, have the
   generic "comm" filter have its own filter_type (FILTER_COMM). Test
   against the type instead of the name to assign the filter function.

3) Add a new "COMM" filter that works just like "comm" but will filter based
   on the current task, even if the trace event contains a "comm" field.

Do the same for "cpu" field, adding a FILTER_CPU and a filter "CPU".

Cc: stable@vger.kernel.org # v4.3+
Fixes: 9f61668073a8d "tracing: Allow triggers to filter for CPU ids and process names"
Reported-by: Matt Fleming 
Signed-off-by: Steven Rostedt

tracing: Implement event pid filtering

2015-10-26T01:33:56+00:00

Add the necessary hooks to use the pids loaded in set_event_pid to filter
all the events enabled in the tracing instance that match the pids listed.

Two probes are added to both sched_switch and sched_wakeup tracepoints to be
called before other probes are called and after the other probes are called.
The first is used to set the necessary flags to let the probes know to test
if they should be traced or not.

The sched_switch pre probe will set the "ignore_pid" flag if neither the
previous or next task has a matching pid.

The sched_switch probe will set the "ignore_pid" flag if the next task
does not match the matching pid.

The pre probe allows for probes tracing sched_switch to be traced if
necessary.

The sched_wakeup pre probe will set the "ignore_pid" flag if neither the
current task nor the wakee task has a matching pid.

The sched_wakeup post probe will set the "ignore_pid" flag if the current
task does not have a matching pid.

Cc: "Paul E. McKenney" 
Signed-off-by: Steven Rostedt

tracing: Pass trace_array into trace_buffer_unlock_commit()

2015-09-25T21:38:44+00:00

In preparation for having trace options be per instance, the trace_array
needs to be passed to the trace_buffer_unlock_commit(). The
trace_event_buffer_lock_reserve() already passes in the trace_event_file
where the trace_array can be derived from.

Also added a "__init" to the boot up test event plus function tracing
function function_test_events_call().

Signed-off-by: Steven Rostedt

tracing: Remove unused function trace_current_buffer_lock_reserve()

2015-09-25T19:37:31+00:00

trace_current_buffer_lock_reserve() is not used by anything. Might as well
get rid of it.

Signed-off-by: Steven Rostedt

tracing, perf: Implement BPF programs attached to uprobes

2015-08-06T18:29:14+00:00

By copying BPF related operation to uprobe processing path, this patch
allow users attach BPF programs to uprobes like what they are already
doing on kprobes.

After this patch, users are allowed to use PERF_EVENT_IOC_SET_BPF on a
uprobe perf event. Which make it possible to profile user space programs
and kernel events together using BPF.

Because of this patch, CONFIG_BPF_EVENTS should be selected by
CONFIG_UPROBE_EVENT to ensure trace_call_bpf() is compiled even if
KPROBE_EVENT is not set.

Signed-off-by: Wang Nan 
Acked-by: Alexei Starovoitov 
Cc: Brendan Gregg 
Cc: Daniel Borkmann 
Cc: David Ahern 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Kaixu Xia 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1435716878-189507-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

bpf: Use correct #ifdef controller for trace_call_bpf()

2015-08-06T18:27:37+00:00

Commit e1abf2cc8d5d80b41c4419368ec743ccadbb131e ("bpf: Fix the build on
BPF_SYSCALL=y && !CONFIG_TRACING kernels, make it more configurable")
updated the building condition of bpf_trace.o from CONFIG_BPF_SYSCALL
to CONFIG_BPF_EVENTS, but the corresponding #ifdef controller in
trace_events.h for trace_call_bpf() was not changed. Which, in theory,
is incorrect.

With current Kconfigs, we can create a .config with CONFIG_BPF_SYSCALL=y
and CONFIG_BPF_EVENTS=n by unselecting CONFIG_KPROBE_EVENT and
selecting CONFIG_BPF_SYSCALL. With these options, trace_call_bpf() will
be defined as an extern function, but if anyone calls it a symbol missing
error will be triggered since bpf_trace.o was not built.

This patch changes the #ifdef controller for trace_call_bpf() from
CONFIG_BPF_SYSCALL to CONFIG_BPF_EVENTS. I'll show its correctness:

Before this patch:

   BPF_SYSCALL   BPF_EVENTS   trace_call_bpf   bpf_trace.o
   y             y           normal           compiled
   n             n           inline           not compiled
   y             n           normal           not compiled (incorrect)
   n             y          impossible (BPF_EVENTS depends on BPF_SYSCALL)

After this patch:

   BPF_SYSCALL   BPF_EVENTS   trace_call_bpf   bpf_trace.o
   y             y           normal           compiled
   n             n           inline           not compiled
   y             n           inline           not compiled (fixed)
   n             y          impossible (BPF_EVENTS depends on BPF_SYSCALL)

So this patch doesn't break anything. QED.

Signed-off-by: Wang Nan 
Cc: Alexei Starovoitov 
Cc: Brendan Gregg 
Cc: Daniel Borkmann 
Cc: David Ahern 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Kaixu Xia 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1435716878-189507-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

tracing: Rename ftrace_trigger_soft_disabled() to trace_trigger_soft_disabled()

2015-05-13T19:25:39+00:00

The name "ftrace" really refers to the function hook infrastructure. It
is not about the trace_events. The ftrace_trigger_soft_disabled() tests if a
trace_event is soft disabled (called but not traced), and returns true if
it is. It has nothing to do with function tracing and should be renamed.

Signed-off-by: Steven Rostedt