linux-toradex.git/kernel/trace/trace_syscalls.c, branch v2.6.35-rc3

perf_events, trace: Fix probe unregister race

2010-05-31T06:46:09+00:00

tracepoint_probe_unregister() does not synchronize against the probe
callbacks, so do that explicitly. This properly serializes the callbacks
and the free of the data used therein.

Also, use this_cpu_ptr() where possible.

Acked-by: Frederic Weisbecker 
Signed-off-by: Peter Zijlstra 
LKML-Reference: <1274438476.1674.1702.camel@laptop>
Signed-off-by: Ingo Molnar

Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip into trace/tip/tracing/core-7

2010-05-21T15:49:57+00:00

Conflicts:
	include/linux/ftrace_event.h
	include/trace/ftrace.h
	kernel/trace/trace_event_perf.c
	kernel/trace/trace_kprobe.c
	kernel/trace/trace_syscalls.c

Signed-off-by: Steven Rostedt

perf, trace: Optimize tracepoints by using per-tracepoint-per-cpu hlist to track events

2010-05-21T09:37:56+00:00

Avoid the swevent hash-table by using per-tracepoint
hlists.

Also, avoid conditionals on the fast path by ordering
with probe unregister so that we should never get on
the callback path without the data being there.

Signed-off-by: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Paul Mackerras 
Cc: Mike Galbraith 
Cc: Steven Rostedt 
LKML-Reference: <20100521090710.473188012@chello.nl>
Signed-off-by: Ingo Molnar

perf, trace: Optimize tracepoints by removing IRQ-disable from perf/tracepoint interaction

2010-05-21T09:37:56+00:00

Improves performance.

Acked-by: Frederic Weisbecker 
Signed-off-by: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Paul Mackerras 
Cc: Mike Galbraith 
Cc: Steven Rostedt 
LKML-Reference: <1274259525.5605.10352.camel@twins>
Signed-off-by: Ingo Molnar

perf/ftrace: Optimize perf/tracepoint interaction for single events

2010-05-18T16:35:46+00:00

When we've got but a single event per tracepoint
there is no reason to try and multiplex it so don't.

Signed-off-by: Peter Zijlstra 
Tested-by: Ingo Molnar 
Cc: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Arnaldo Carvalho de Melo 
LKML-Reference: 
Signed-off-by: Ingo Molnar

tracing: Remove duplicate id information in event structure

2010-05-14T18:33:15+00:00

Now that the trace_event structure is embedded in the ftrace_event_call
structure, there is no need for the ftrace_event_call id field.
The id field is the same as the trace_event type field.

Removing the id and re-arranging the structure brings down the tracepoint
footprint by another 5K.

   text	   data	    bss	    dec	    hex	filename
4913961	1088356	 861512	6863829	 68bbd5	vmlinux.orig
4895024	1023812	 861512	6780348	 6775bc	vmlinux.print
4894944	1018052	 861512	6774508	 675eec	vmlinux.id

Acked-by: Mathieu Desnoyers 
Acked-by: Masami Hiramatsu 
Acked-by: Frederic Weisbecker 
Signed-off-by: Steven Rostedt

tracing: Move print functions into event class

2010-05-14T18:20:34+00:00

Currently, every event has its own trace_event structure. This is
fine since the structure is needed anyway. But the print function
structure (trace_event_functions) is now separate. Since the output
of the trace event is done by the class (with the exception of events
defined by DEFINE_EVENT_PRINT), it makes sense to have the class
define the print functions that all events in the class can use.

This makes a bigger deal with the syscall events since all syscall events
use the same class. The savings here is another 30K.

   text	   data	    bss	    dec	    hex	filename
4913961	1088356	 861512	6863829	 68bbd5	vmlinux.orig
4900382	1048964	 861512	6810858	 67ecea	vmlinux.init
4900446	1049028	 861512	6810986	 67ed6a	vmlinux.preprint
4895024	1023812	 861512	6780348	 6775bc	vmlinux.print

To accomplish this, and to let the class know what event is being
printed, the event structure is embedded in the ftrace_event_call
structure. This should not be an issues since the event structure
was created for each event anyway.

Acked-by: Mathieu Desnoyers 
Acked-by: Masami Hiramatsu 
Acked-by: Frederic Weisbecker 
Signed-off-by: Steven Rostedt

tracing: Allow events to share their print functions

2010-05-14T18:20:32+00:00

Multiple events may use the same method to print their data.
Instead of having all events have a pointer to their print funtions,
the trace_event structure now points to a trace_event_functions structure
that will hold the way to print ouf the event.

The event itself is now passed to the print function to let the print
function know what kind of event it should print.

This opens the door to consolidating the way several events print
their output.

   text	   data	    bss	    dec	    hex	filename
4913961	1088356	 861512	6863829	 68bbd5	vmlinux.orig
4900382	1048964	 861512	6810858	 67ecea	vmlinux.init
4900446	1049028	 861512	6810986	 67ed6a	vmlinux.preprint

This change slightly increases the size but is needed for the next change.

v3: Fix the branch tracer events to handle this change.

v2: Fix the new function graph tracer event calls to handle this change.

Acked-by: Mathieu Desnoyers 
Acked-by: Masami Hiramatsu 
Acked-by: Frederic Weisbecker 
Signed-off-by: Steven Rostedt

tracing: Move raw_init from events to class

2010-05-14T18:20:30+00:00

The raw_init function pointer in the event is used to initialize
various kinds of events. The type of initialization needed is usually
classed to the kind of event it is.

Two events with the same class will always have the same initialization
function, so it makes sense to move this to the class structure.

Perhaps even making a special system structure would work since
the initialization is the same for all events within a system.
But since there's no system structure (yet), this will just move it
to the class.

   text	   data	    bss	    dec	    hex	filename
4913961	1088356	 861512	6863829	 68bbd5	vmlinux.orig
4900375	1053380	 861512	6815267	 67fe23	vmlinux.fields
4900382	1048964	 861512	6810858	 67ecea	vmlinux.init

The text grew very slightly, but this is a constant growth that happened
with the changing of the C files that call the init code.
The bigger savings is the data which will be saved the more events share
a class.

Acked-by: Mathieu Desnoyers 
Acked-by: Masami Hiramatsu 
Acked-by: Frederic Weisbecker 
Signed-off-by: Steven Rostedt

tracing: Move fields from event to class structure

2010-05-14T18:20:23+00:00

Move the defined fields from the event to the class structure.
Since the fields of the event are defined by the class they belong
to, it makes sense to have the class hold the information instead
of the individual events. The events of the same class would just
hold duplicate information.

After this change the size of the kernel dropped another 3K:

   text	   data	    bss	    dec	    hex	filename
4913961	1088356	 861512	6863829	 68bbd5	vmlinux.orig
4900252	1057412	 861512	6819176	 680d68	vmlinux.regs
4900375	1053380	 861512	6815267	 67fe23	vmlinux.fields

Although the text increased, this was mainly due to the C files
having to adapt to the change. This is a constant increase, where
new tracepoints will not increase the Text. But the big drop is
in the data size (as well as needed allocations to hold the fields).
This will give even more savings as more tracepoints are created.

Note, if just TRACE_EVENT()s are used and not DECLARE_EVENT_CLASS()
with several DEFINE_EVENT()s, then the savings will be lost. But
we are pushing developers to consolidate events with DEFINE_EVENT()
so this should not be an issue.

The kprobes define a unique class to every new event, but are dynamic
so it should not be a issue.

The syscalls however have a single class but the fields for the individual
events are different. The syscalls use a metadata to define the
fields. I moved the fields list from the event to the metadata and
added a "get_fields()" function to the class. This function is used
to find the fields. For normal events and kprobes, get_fields() just
returns a pointer to the fields list_head in the class. For syscall
events, it returns the fields list_head in the metadata for the event.

v2:  Fixed the syscall fields. The syscall metadata needs a list
     of fields for both enter and exit.

Acked-by: Frederic Weisbecker 
Acked-by: Mathieu Desnoyers 
Acked-by: Masami Hiramatsu 
Cc: Tom Zanussi 
Cc: Peter Zijlstra 
Signed-off-by: Steven Rostedt