When we enter in irq, two things can happen to preserve the link
to the previous frame pointer:
- If we were in an irq already, we don't switch to the irq stack
as we are inside. We just need to save the previous frame
pointer and to link the new one to the previous.
- Otherwise we need another level of indirection. We enter the irq with
the previous stack. We save the previous bp inside and make bp
pointing to its saved address. Then we switch to the irq stack and
push bp another time but to the new stack. This makes two levels to
dereference instead of one.
In the second case, the current stacktrace code omits the second level
and loses the frame pointer accuracy. The stack that follows will then
be considered as unreliable.
Handling that makes the perf callchain happier.
Before:
x86: Fixup wrong debug exception frame link in stacktraces
While dumping a stacktrace, the end of the exception stack won't link
the frame pointer to the previous stack.
The interrupted stack will then be considered as unreliable and ignored
by perf, as the frame pointer is unreliable itself.
This happens because we overwrite the frame pointer that links to the
interrupted frame with the address of the exception stack. This is
done in order to reserve space inside.
But rbp has been chosen here only because it is not a scratch register,
so that the address of the exception stack remains in rbp after calling
do_debug(), we can then release the exception stack space without the
need to retrieve its address again.
But we can pick another non-scratch register to do that, so that we
preserve the link to the interrupted stack frame in the stacktraces.
Just randomly choose r12. Every registers are saved just before and
restored just after calling do_debug(). And r12 is not used in the
middle, which makes it a perfect candidate.
Example: perf record -g -a -c 1 -f -e mem:$(tasklist_lock_addr):rw
We are infected with all the debug stack. Like the nmi stack, the debug
stack is undesired as it is part of the profiling path, not helpful for
the user.
Ignore it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
hw-breakpoints: Use overflow handler instead of the event callback
struct perf_event::event callback was called when a breakpoint
triggers. But this is a rather opaque callback, pretty
tied-only to the breakpoint API and not really integrated into perf
as it triggers even when we don't overflow.
We prefer to use overflow_handler() as it fits into the perf events
rules, being called only when we overflow.
Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
hw-breakpoints: Drop callback and task parameters from modify helper
Drop the callback and task parameters from modify_user_hw_breakpoint().
For now we have no user that need to modify a breakpoint to the point
of changing its handler or its task context.
Jason Baron [Tue, 1 Dec 2009 17:18:49 +0000 (12:18 -0500)]
tracing: Add DEFINE_EVENT(), DEFINE_SINGLE_EVENT() support to docbook
The introduction of the new 'DECLARE_EVENT_CLASS()' obviates the
need for the 'TRACE_EVENT()' macro in some cases. Thus, docbook
style comments that used to live with 'TRACE_EVENT()' are now
moved to 'DEFINE_EVENT()'. Thus, we need to make the docbook
system understand the new 'DEFINE_EVENT()' macro. In addition
I've tried to futureproof the patch, by also adding support for
'DEFINE_SINGLE_EVENT()', since there has been discussion about
renaming: TRACE_EVENT() -> DEFINE_SINGLE_EVENT().
Without this patch the tracepoint docbook fails to build.
I've verified that this patch correctly builds the tracepoint
docbook which currently covers signals, and irqs.
Changes in v2:
- properly indent perl 'if' statements
Signed-off-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: William Cohen <wcohen@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <200912011718.nB1HIn7t011371@int-mx04.intmail.prod.int.phx2.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf: Don't free perf_mmap_data until work has been done
In the CONFIG_PERF_USE_VMALLOC case, perf_mmap_data_free() only
schedules the cleanup of the perf_mmap_data struct. In that
case we have to wait until the work has been done before we free
data.
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: <stable@kernel.org>
LKML-Reference: <1259697901-1747-1-git-send-email-krh@bitplanet.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Simplify event naming as <symbol>_<seqnum>. Each event name is
globally unique (group name is not checked). So, if there is
schedule_0, next probe event on schedule() will be schedule_1.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091201002024.10235.2353.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf probe: Change a debugging message from pr_info to pr_debug
Change annoying debug-info using notice from pr_info() to
pr_debug(), since the message always printed when user adds a
probe point which requires debug-info.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091201001927.10235.63645.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu>
trace_kprobes: Fix a memory leak bug and check kstrdup() return value
Fix a memory leak case in create_trace_probe(). When an argument
is too long (> MAX_ARGSTR_LEN), it just jumps to error path. In
that case tp->args[i].name is not released.
This also fixes a bug to check kstrdup()'s return value.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091201001919.10235.56455.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Convert builtin-timechart.c to mmap_dispatch_perf_file() +
perf_file_handler.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Arjan van de Ven <arjan@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4B14B21C.2040406@cn.fujitsu.com>
[ v2: cleaned up the printout, fixed a whitespace detail ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
Li Zefan [Tue, 1 Dec 2009 06:04:49 +0000 (14:04 +0800)]
perf annotate: Fix perf data parsing
perf-annotate doesn't parse perf.data correctly in that it
doesn't read perf header. Fix this by using
mmap_dispatch_perf_file().
Before:
TOTAL events: 17565
MMAP events: 3221
LOST events: 10
COMM events: 235
EXIT events: 2
THROTTLE events: 1
UNTHROTTLE events: 2
FORK events: 10
READ events: 1
SAMPLE events: 14083
After:
TOTAL events: 17290
MMAP events: 3203
LOST events: 0
COMM events: 234
EXIT events: 1
THROTTLE events: 0
UNTHROTTLE events: 0
FORK events: 0
READ events: 0
SAMPLE events: 13852
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <4B14B201.9030708@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
The common_* functions (e.g. common_pc(), etc) are exported as
common_* but named get_common_*, resulting in unresolved
subroutine errors when executing scripts.
Tom Zanussi [Mon, 30 Nov 2009 07:18:47 +0000 (01:18 -0600)]
perf trace/scripting: Ignore shadowed variable warning for perf-trace-perl.c
The debugging versions of the ENTER and LEAVE internal perl
macros, used when embedding perl, define a local block with a
my_perl perl variable that shadows a global variable of the same
name, which is also the name expected by the embedding API for
the embedded interpreter.
Since we don't have control over the code generated in this case
(it's an externality) and can't get rid of the warning, ignore it.
Tom Zanussi [Wed, 25 Nov 2009 07:15:52 +0000 (01:15 -0600)]
perf trace: Add a scripts/perl/bin for perf trace shell scripts
To capture the relevant events for a given Perl script and to
avoid having to continually remember and type in long
command-lines, add a scripts/perl/bin directory containing two
simple shell scripts for each Perl script, one for recording and
one for processing/display. For example, to record perf data for
the rw-by-pid.pl script, run scripts/perl/bin/rw-by-pid-record
and to actually run the script and display the output run
scripts/perl/bin/rw-by-pid-report.
Tom Zanussi [Wed, 25 Nov 2009 07:15:50 +0000 (01:15 -0600)]
perf trace: Add interface to access perf data from Perl handlers
The Perl scripting support for perf trace allows most of a trace
event's data to be accessed directly as handler arguments, but
not all of it e.g. the less common fields aren't passed in. To
give scripts access to the other fields and/or any other data or
metadata in the main perf executable that might be useful, a way
to access the C data in perf from Perl is needed; this patch
uses the Perl XS facility to do it for the common_xxx event
fields not passed to handler functions.
Context.pm exports three functions to Perl scripts that access
fields for the current event by calling back into perf:
common_pc(), common_flags() and common_lock_depth(). Support
for common_flags() field values was added to Core.pm and a
script used to sanity check these and other basic scripting
features, check-perf-trace.pl, was also added.
Tom Zanussi [Wed, 25 Nov 2009 07:15:49 +0000 (01:15 -0600)]
perf trace: Add perf trace scripting support modules for Perl
Add Perf-Trace-Util Perl module and some scripts that use it.
Core.pm contains Perl code to define and access flag and
symbolic fields. Util.pm contains general-purpose utility
functions.
Also adds some makefile bits to install them in
libexec/perf-core/scripts/perl (or wherever perfexec_instdir
points).
Tom Zanussi [Wed, 25 Nov 2009 07:15:48 +0000 (01:15 -0600)]
perf trace: Add Perl scripting support
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.
Tom Zanussi [Wed, 25 Nov 2009 07:15:47 +0000 (01:15 -0600)]
perf trace: Add flag/symbolic format_flags
It's useful to know whether a field is a flag or symbolic field
for e.g. when generating scripts - it allows us to translate
those fields specially rather than literally as plain numeric
values.
Tom Zanussi [Wed, 25 Nov 2009 07:15:46 +0000 (01:15 -0600)]
perf trace: Add scripting ops
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:
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:
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.
perf tools: Consolidate symbol resolving across all tools
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).
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? :-)
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.
perf symbols: Support multiple symtabs in struct thread
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.
perf symbols: Make the kallsyms loading routines part of the dso class
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.
perf symbols: Better support for multiple symbol tables per dso
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).
perf symbols: Split the dsos list into kernel and user parts
We don't need to look at modules in dsos__findnew because the
kernel events come only with user DSOs. Also we need a way to
list just the module DSOs so that we can create multiple sets of
maps, now that we will support maps for the variables in a
symtab.
hw-breakpoints: Use struct perf_event_attr to define kernel breakpoints
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.
hw-breakpoints: Use struct perf_event_attr to define user breakpoints
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.
Stephane Eranian [Thu, 26 Nov 2009 17:24:30 +0000 (09:24 -0800)]
perf_events: Fix read() bogus counts when in error state
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>
Ingo Molnar [Thu, 26 Nov 2009 12:11:46 +0000 (13:11 +0100)]
tracing: Fix kmem event exports
Commit 53d0422 ("tracing: Convert some kmem events to DEFINE_EVENT")
moved the kmem tracepoint creation from util.c to page_alloc.c,
but forgot to move the exports.
Move them back.
Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie>
LKML-Reference: <4B0E286A.2000405@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Hidetoshi Seto [Thu, 26 Nov 2009 08:29:02 +0000 (17:29 +0900)]
x86, mce: Add __cpuinit to hotplug callback functions
The mce_disable_cpu() and mce_reenable_cpu() are called only
from mce_cpu_callback() which is marked as __cpuinit.
So these functions can be __cpuinit too.
If the new percpu tree is combined with the perf events tree
the following new warning triggers:
kernel/hw_breakpoint.c: In function 'toggle_bp_task_slot':
kernel/hw_breakpoint.c:151: warning: 'task_bp_pinned' is used uninitialized in this function
Because it's not valid anymore to define a local variable
and a percpu variable (even if it's file scope local) with
the same name.
x86/hw-breakpoints: Don't lose GE flag while disabling a breakpoint
When we schedule out a breakpoint from the cpu, we also
incidentally remove the "Global exact breakpoint" flag from the
breakpoint control register. It makes us losing the fine grained
precision about the origin of the instructions that may trigger
breakpoint exceptions for the other breakpoints running in this
cpu.
hw-breakpoints: Simplify error handling in breakpoint creation requests
This simplifies the error handling when we create a breakpoint.
We don't need to check the NULL return value corner case anymore
since we have improved perf_event_create_kernel_counter() to
always return an error code in the failure case.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1259210142-5714-3-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
In fail case, perf_event_create_kernel_counter() returns NULL
instead of an error, which doesn't help us to inform the user
about the origin of the problem from the outer most callers.
Often we can just return -EINVAL, which doesn't help anyone when
it's eventually about a memory allocation failure.
Then, this patch makes perf_event_create_kernel_counter() always
return a detailed error code.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1259210142-5714-2-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
ksym_tracer: Fix breakpoint removal after modification
The error path of a breakpoint modification is broken in
the ksym tracer. A modified breakpoint hlist node is immediately
released after its removal. Also we leak a breakpoint in this
case.
Li Zefan [Thu, 26 Nov 2009 07:05:38 +0000 (15:05 +0800)]
tracing: Convert some power events to DEFINE_EVENT
Use DECLARE_EVENT_CLASS to remove duplicate code:
text data bss dec hex filename
4312 524 12 4848 12f0 kernel/trace/power-traces.o.old
3455 524 8 3987 f93 kernel/trace/power-traces.o
Two events are converted:
power: power_start, power_frequency
No change in functionality.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <4B0E28C2.1090906@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tejun Heo [Wed, 25 Nov 2009 13:24:44 +0000 (22:24 +0900)]
x86: Rename global percpu symbol dr7 to cpu_dr7
Percpu symbols now occupy the same namespace as other global
symbols and as such short global symbols without subsystem
prefix tend to collide with local variables. dr7 percpu
variable used by x86 was hit by this. Rename it to cpu_dr7.
The rename also makes it more consistent with its fellow
cpu_debugreg percpu variable.
Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org>, Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <20091125115856.GA17856@elte.hu> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tom Zanussi [Wed, 25 Nov 2009 07:14:59 +0000 (01:14 -0600)]
trace/syscalls: Change ret param in struct syscall_trace_exit to long
Commit ee949a86b3aef15845ea677aa60231008de62672 ("tracing/syscalls:
Use long for syscall ret format and field definitions") changed the
syscall exit return type to long, but forgot to change it in the
struct.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259133299-23594-3-git-send-email-tzanussi@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Steven Rostedt [Thu, 19 Nov 2009 01:48:08 +0000 (20:48 -0500)]
tracing: Convert some sched trace events to DEFINE_EVENT and _PRINT
Converting some of the scheduler trace events to use the
TRACE_EVENT_TEMPLATE, DEFINE_EVENT and DEFINE_EVENT_PRINT helped to
save some space:
$ size kernel/sched.o-*
text data bss dec hex filename
79299 6776 2520 88595 15a13 kernel/sched.o-notrace
101941 11896 2584 116421 1c6c5 kernel/sched.o-templ
104779 11896 2584 119259 1d1db kernel/sched.o-trace
sched.o-notrace is without any tracepoints compiled
sched.o-templ is with this patch
sched.o-trace is the tracepoints before this patch
The trace events converted to DEFINE_EVENT:
sched_wakeup, sched_wakeup_new, sched_process_free, sched_process_exit,
and sched_stat_wait.
The trace events converted to DEFINE_EVENT_PRINT:
sched_stat_sleep and sched_stat_iowait.
Note, since the TRACE_EVENT_TEMPLATE always uses a print, the
sched_stat_wait print format is defined in the template and this
template is used by sched_stat_sleep and sched_stat_iowait. But the
later two override the print format.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Steven Rostedt [Thu, 19 Nov 2009 01:36:26 +0000 (20:36 -0500)]
tracing: Create new DEFINE_EVENT_PRINT
After creating the TRACE_EVENT_TEMPLATE I started to look at other
trace points to see what duplication was made. I noticed that there
are several trace points where they are almost identical except for
the name and the output format. Since TRACE_EVENT_TEMPLATE was successful
in bringing down the size of trace events, I added a DEFINE_EVENT_PRINT.
DEFINE_EVENT_PRINT is used just like DEFINE_EVENT is. That is, the
DEFINE_EVENT_PRINT also uses a TRACE_EVENT_TEMPLATE, but it allows the
developer to overwrite the print format. If there are two or more
TRACE_EVENTS that are identical except for the name and print, then
they can be converted to use a TRACE_EVENT_TEMPLATE. Since the
TRACE_EVENT_TEMPLATE already does the print output, the first trace event
would have its print format held in the TRACE_EVENT_TEMPLATE and
be defined with a DEFINE_EVENT. The rest will use the DEFINE_EVENT_PRINT
and override the print format.
Converting the sched trace points to both DEFINE_EVENT and
DEFINE_EVENT_PRINT. Five were converted to DEFINE_EVENT and two were
converted to DEFINE_EVENT_PRINT.
I was able to get the following:
$ size kernel/sched.o-*
text data bss dec hex filename
79299 6776 2520 88595 15a13 kernel/sched.o-notrace
101941 11896 2584 116421 1c6c5 kernel/sched.o-templ
104779 11896 2584 119259 1d1db kernel/sched.o-trace
sched.o-notrace is the scheduler compiled with no trace points.
sched.o-templ is with the use of DEFINE_EVENT and DEFINE_EVENT_PRINT
sched.o-trace is the current trace events.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Steven Rostedt [Thu, 19 Nov 2009 01:27:27 +0000 (20:27 -0500)]
tracing: Create new TRACE_EVENT_TEMPLATE
There are some places in the kernel that define several tracepoints and
they are all identical besides the name. The code to enable, disable and
record is created for every trace point even if most of the code is
identical.
This patch adds TRACE_EVENT_TEMPLATE that lets the developer create
a template TRACE_EVENT and create trace points with DEFINE_EVENT, which
is based off of a given template. Each trace point used by this
will share most of the code, and bring down the size of the kernel
when there are several duplicate events.
Usage is:
TRACE_EVENT_TEMPLATE(name, proto, args, tstruct, assign, print);
Which would be the same as defining a normal TRACE_EVENT.
To create the trace events that the trace points will use:
DEFINE_EVENT(template, name, proto, args) is done. The template
is the name of the TRACE_EVENT_TEMPLATE to use. The name is the
name of the trace point. The parameters proto and args must be the same
as the proto and args of the template. If they are not the same,
then a compile error will result. I tried hard removing this duplication
but the C preprocessor is not powerful enough (or my CPP magic
experience points is not at a high enough level) to not need them.
A lot of trace events are coming in with new XFS development. Most of
the trace points are identical except for the name. The following shows
the advantage of having TRACE_EVENT_TEMPLATE:
$ size fs/xfs/xfs.o.*
text data bss dec hex filename
452114 2788 3520 458422 6feb6 fs/xfs/xfs.o.old
638482 38116 3744 680342 a6196 fs/xfs/xfs.o.template
996954 38116 4480 1039550 fdcbe fs/xfs/xfs.o.trace
xfs.o.old is without any tracepoints.
xfs.o.template uses the new TRACE_EVENT_TEMPLATE.
xfs.o.trace uses the current TRACE_EVENT macros.
Requested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
perf_events: Fix bad software/trace event recursion counting
Commit 4ed7c92d68a5387ba5f7030dc76eab03558e27f5
(perf_events: Undo some recursion damage) has introduced a bad
reference counting of the recursion context. putting the context
behaves like getting it, dropping every software/trace events
after the first one in a context.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1259091502-5171-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stephane Eranian [Tue, 24 Nov 2009 13:27:18 +0000 (05:27 -0800)]
perf_events, x86: Fix validate_event bug
The validate_event() was failing on valid event combinations. The
function was assuming that if x86_schedule_event() returned 0, it
meant error. But x86_schedule_event() returns the counter index and
0 is a perfectly valid value. An error is returned if the function
returns a negative value.
Furthermore, validate_event() was also failing for event groups
because the event->pmu was not set until after
hw_perf_event_init().