Implement trace_scripting_ops to make Perl a supported perf
trace scripting language.
Additionally adds code that allows Perl trace scripts to access
the 'flag' and 'symbolic' (__print_flags(), __print_symbolic())
field information parsed from the trace format files.
Also adds the Perl implementation of the generate_script()
trace_scripting_op, which creates a ready-to-run perf trace Perl
script based on existing trace data. Scripts generated by this
implementation print out all the fields for each event mentioned
in perf.data (and will detect and generate the proper scripting
code for 'flag' and 'symbolic' fields), and will additionally
generate handlers for the special 'trace_unhandled',
'trace_begin' and 'trace_end' handlers. Script authors can
simply remove the printing code to implement their own custom
event handling.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: anton@samba.org
Cc: hch@infradead.org
LKML-Reference: <1259133352-23685-4-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Adds an interface, scripting_ops, that when implemented for a
particular scripting language enables built-in support for trace
stream processing using that language.
The interface is designed to enable full-fledged language
interpreters to be embedded inside the perf executable and
thereby make the full capabilities of the supported languages
available for trace processing.
See below for details on the interface.
This patch also adds a couple command-line options to 'perf
trace':
The -s option option is used to specify the script to be run.
Script names that can be used with -s take the form:
[language spec:]scriptname[.ext]
Scripting languages register a set of 'language specs' that can
be used to specify scripts for the registered languages. The
specs can be used either as prefixes or extensions.
If [language spec:] is used, the script is taken as a script of
the matching language regardless of any extension it might have.
If [language spec:] is not used, [.ext] is used to look up the
language it corresponds to. Language specs are case
insensitive.
e.g. Perl scripts can be specified in the following ways:
Perl:scriptname
pl:scriptname.py # extension ignored
PL:scriptname
scriptname.pl
scriptname.perl
The -g [language spec] option gives users an easy starting point
for writing scripts in the specified language. Scripting
support for a particular language can implement a
generate_script() scripting op that outputs an empty (or
near-empty) set of handlers for all the events contained in a
given perf.data trace file - this option gives users a direct
way to access that.
Adding support for a scripting language
---------------------------------------
The main thing that needs to be done do add support for a new
language is to implement the scripting_ops interface:
It consists of the following four functions:
start_script()
stop_script()
process_event()
generate_script()
start_script() is called before any events are processed, and is
meant to give the scripting language support an opportunity to
set things up to receive events e.g. create and initialize an
instance of a language interpreter.
stop_script() is called after all events are processed, and is
meant to give the scripting language support an opportunity to
clean up e.g. destroy the interpreter instance, etc.
process_event() is called once for each event and takes as its
main parameter a pointer to the binary trace event record to be
processed. The implementation is responsible for picking out the
binary fields from the event record and sending them to the
script handler function associated with that event e.g. a
function derived from the event name it's meant to handle e.g.
'sched::sched_switch()'. The 'format' information for trace
events can be used to parse the binary data and map it into a
form usable by a given scripting language; see the Perl
implemention in subsequent patches for one possible way to
leverage the existing trace format parsing code in perf and map
that info into specific scripting language types.
generate_script() should generate a ready-to-run script for the
current set of events in the trace, preferably with bodies that
print out every field for each event. Again, look at the Perl
implementation for clues as to how that can be done. This is an
optional, but very useful op.
Support for a given language should also add a language-specific
setup function and call it from setup_scripting(). The
language-specific setup function associates the the scripting
ops for that language with one or more 'language specifiers'
(see below) using script_spec_register(). When a script name is
specified on the command line, the scripting ops associated with
the specified language are used to instantiate and use the
appropriate interpreter to process the trace stream.
In general, it should be relatively easy to add support for a
new language, especially if the language implementation supports
an interface allowing an interpreter to be 'embedded' inside
another program (in this case the containing program will be
'perf trace'). If so, it should be relatively straightforward to
translate trace events into invocations of user-defined script
functions where e.g. the function name corresponds to the event
type and the function parameters correspond to the event fields.
The event and field type information exported by the event
tracing infrastructure (via the event 'format' files) should be
enough to parse and send any piece of trace data to the user
script. The easiest way to see how this can be done would be to
look at the Perl implementation contained in
perf/util/trace-event-perl.c/.h.
There are a couple of other things that aren't covered by the
scripting_ops or setup interface and are technically optional,
but should be implemented if possible. One of these is support
for 'flag' and 'symbolic' fields e.g. being able to use more
human-readable values such as 'GFP_KERNEL' or
HI/BLOCK_IOPOLL/TASKLET in place of raw flag values. See the
Perl implementation to see how this can be done. The other thing
is support for 'calling back' into the perf executable to access
e.g. uncommon fields not passed by default into handler
functions, or any metadata the implementation might want to make
available to users via the language interface. Again, see the
Perl implementation for examples.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: anton@samba.org
Cc: hch@infradead.org
LKML-Reference: <1259133352-23685-2-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now we have a very high level routine for simple tools to
process IP sample events:
int event__preprocess_sample(const event_t *self,
struct addr_location *al,
symbol_filter_t filter)
It receives the event itself and will insert new threads in the
global threads list and resolve the map and symbol, filling all
this info into the new addr_location struct, so that tools like
annotate and report can further process the event by creating
hist_entries in their specific way (with or without callgraphs,
etc).
It in turn uses the new next layer function:
void thread__find_addr_location(struct thread *self, u8 cpumode,
enum map_type type, u64 addr,
struct addr_location *al,
symbol_filter_t filter)
This one will, given a thread (userspace or the kernel kthread
one), will find the given type (MAP__FUNCTION now, MAP__VARIABLE
too in the near future) at the given cpumode, taking vdsos into
account (userspace hit, but kernel symbol) and will fill all
these details in the addr_location given.
Tools that need a more compact API for plain function
resolution, like 'kmem', can use this other one:
struct symbol *thread__find_function(struct thread *self, u64 addr,
symbol_filter_t filter)
So, to resolve a kernel symbol, that is all the 'kmem' tool
needs, its just a matter of calling:
sym = thread__find_function(kthread, addr, NULL);
The 'filter' parameter is needed because we do lazy
parsing/loading of ELF symtabs or /proc/kallsyms.
With this we remove more code duplication all around, which is
always good, huh? :-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1259346563-12568-12-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While implementing event__preprocess_sample, that will do all of
the symbol lookup in one convenient function, I noticed that
util/process_event.[ch] were not being used at all, then started
looking if there were other functions that could be shared
and...
All those functions really don't need to receive offset + head,
the only thing they did was common to all of them, so do it at
one place instead.
Stats about number of each type of event processed now is done
in a central place.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1259346563-12568-11-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Making the routines that were so far specific to the kernel maps
useful for all threads.
This is done by making the kernel maps be contained in a kernel
"thread".
This gets the kernel specific routines closer to the userspace
counterparts, which will help in reducing the boilerplate for
resolving a symbol, as will be demonstrated in the next patches.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1259346563-12568-9-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
So that the kallsyms loading routines are the direct counterpart
of the vmlinux loading ones, i.e. dso__load_kallsyms is the
counterpart of dso__load_vmlinux.
In the process make them also use the symbols rb tree indexed by
map->type, paving the way for supporting other types of symtabs,
such as the next one to be supported: variables.
This also allowed removal of yet another global variable:
kernel_map__functions.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1259346563-12568-7-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
By using an array of rb_roots in struct dso we can, from a
struct map instance to get the right symbol rb_tree more easily.
This way we can have just one symbol lookup method for struct
map instances, map__find_symbol, instead of one per symtab type
(functions, variables).
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1259346563-12568-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Sometimes the group name is not "kprobes",
It'll be better if we can read it from tracing/kprobe_events.
# echo 'r:laijs/vfs_read vfs_read %ax' > kprobe_events
# cat kprobe_events
r:laijs/vfs_read vfs_read %ax=%ax
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0CEBAF.6000104@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Kernel breakpoints are created using functions in which we pass
breakpoint parameters as individual variables: address, length
and type.
Although it fits well for x86, this just does not scale across
architectures that may support this api later as these may have
more or different needs. Pass in a perf_event_attr structure
instead because it is meant to evolve as much as possible into
a generic hardware breakpoint parameter structure.
Reported-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259294154-5197-2-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In-kernel user breakpoints are created using functions in which
we pass breakpoint parameters as individual variables: address,
length and type.
Although it fits well for x86, this just does not scale across
archictectures that may support this api later as these may have
more or different needs. Pass in a perf_event_attr structure
instead because it is meant to evolve as much as possible into
a generic hardware breakpoint parameter structure.
Reported-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259294154-5197-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When a pinned group cannot be scheduled it goes into error state.
Normally a group cannot go out of error state without being
explicitly re-enabled or disabled. There was a bug in per-thread
mode, whereby upon termination of the thread, the group would
transition from error to off leading to bogus counts and timing
information returned by read().
Fix it by clearing the error state.
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: perfmon2-devel@lists.sourceforge.net
LKML-Reference: <4b0eb9ce.0508d00a.573b.ffffeab6@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tom Zanussi
Arnaldo Carvalho de Melo
Lai Jiangshan
Frederic Weisbecker
Stephane Eranian
Ingo Molnar
Masami Hiramatsu