Pull user-space probe instrumentation from Ingo Molnar:
"The uprobes code originates from SystemTap and has been used for years
in Fedora and RHEL kernels. This version is much rewritten, reviews
from PeterZ, Oleg and myself shaped the end result.
This tree includes uprobes support in 'perf probe' - but SystemTap
(and other tools) can take advantage of user probe points as well.
Sample usage of uprobes via perf, for example to profile malloc()
calls without modifying user-space binaries.
First boot a new kernel with CONFIG_UPROBE_EVENT=y enabled.
If you don't know which function you want to probe you can pick one
from 'perf top' or can get a list all functions that can be probed
within libc (binaries can be specified as well):
$ perf probe -F -x /lib/libc.so.6
To probe libc's malloc():
$ perf probe -x /lib64/libc.so.6 malloc
Added new event:
probe_libc:malloc (on 0x7eac0)
You can now use it in all perf tools, such as:
perf record -e probe_libc:malloc -aR sleep 1
Make use of it to create a call graph (as the flat profile is going to
look very boring):
$ perf record -e probe_libc:malloc -gR make
[ perf record: Woken up 173 times to write data ]
[ perf record: Captured and wrote 44.190 MB perf.data (~1930712
$ perf report | less
32.03% git libc-2.15.so [.] malloc
|
--- malloc
29.49% cc1 libc-2.15.so [.] malloc
|
--- malloc
|
|--0.95%-- 0x208eb1000000000
|
|--0.63%-- htab_traverse_noresize
11.04% as libc-2.15.so [.] malloc
|
--- malloc
|
7.15% ld libc-2.15.so [.] malloc
|
--- malloc
|
5.07% sh libc-2.15.so [.] malloc
|
--- malloc
|
4.99% python-config libc-2.15.so [.] malloc
|
--- malloc
|
4.54% make libc-2.15.so [.] malloc
|
--- malloc
|
|--7.34%-- glob
| |
| |--93.18%-- 0x41588f
| |
| --6.82%-- glob
| 0x41588f
...
Or:
$ perf report -g flat | less
# Overhead Command Shared Object Symbol
# ........ ............. ............. ..........
#
32.03% git libc-2.15.so [.] malloc
27.19%
malloc
29.49% cc1 libc-2.15.so [.] malloc
24.77%
malloc
11.04% as libc-2.15.so [.] malloc
11.02%
malloc
7.15% ld libc-2.15.so [.] malloc
6.57%
malloc
...
The core uprobes design is fairly straightforward: uprobes probe
points register themselves at (inode:offset) addresses of
libraries/binaries, after which all existing (or new) vmas that map
that address will have a software breakpoint injected at that address.
vmas are COW-ed to preserve original content. The probe points are
kept in an rbtree.
If user-space executes the probed inode:offset instruction address
then an event is generated which can be recovered from the regular
perf event channels and mmap-ed ring-buffer.
Multiple probes at the same address are supported, they create a
dynamic callback list of event consumers.
The basic model is further complicated by the XOL speedup: the
original instruction that is probed is copied (in an architecture
specific fashion) and executed out of line when the probe triggers.
The XOL area is a single vma per process, with a fixed number of
entries (which limits probe execution parallelism).
The API: uprobes are installed/removed via
/sys/kernel/debug/tracing/uprobe_events, the API is integrated to
align with the kprobes interface as much as possible, but is separate
to it.
Injecting a probe point is privileged operation, which can be relaxed
by setting perf_paranoid to -1.
You can use multiple probes as well and mix them with kprobes and
regular PMU events or tracepoints, when instrumenting a task."
Fix up trivial conflicts in mm/memory.c due to previous cleanup of
unmap_single_vma().
* 'perf-uprobes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
perf probe: Detect probe target when m/x options are absent
perf probe: Provide perf interface for uprobes
tracing: Fix kconfig warning due to a typo
tracing: Provide trace events interface for uprobes
tracing: Extract out common code for kprobes/uprobes trace events
tracing: Modify is_delete, is_return from int to bool
uprobes/core: Decrement uprobe count before the pages are unmapped
uprobes/core: Make background page replacement logic account for rss_stat counters
uprobes/core: Optimize probe hits with the help of a counter
uprobes/core: Allocate XOL slots for uprobes use
uprobes/core: Handle breakpoint and singlestep exceptions
uprobes/core: Rename bkpt to swbp
uprobes/core: Make order of function parameters consistent across functions
uprobes/core: Make macro names consistent
uprobes: Update copyright notices
uprobes/core: Move insn to arch specific structure
uprobes/core: Remove uprobe_opcode_sz
uprobes/core: Make instruction tables volatile
uprobes: Move to kernel/events/
uprobes/core: Clean up, refactor and improve the code
...
In order for perf buildid-list to work with pipe-mode files, it needs to
process buildids and event attr structs.
$ perf record -o - noploop 2 | ./perf inject -b | perf buildid-list -i - -H
noploop for 2 seconds
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.084 MB - (~3678 samples) ]
0000000000000000000000000000000000000000 [kernel.kallsyms]
3a0d0629efe74a8da3eeba372cdbd74ad9b8f5d5 /usr/local/bin/noploop
The reason [kernel.kallsyms] shows a 0 build-id comes from the
way buildids are injected in the stream.
The buildid for the kernel is provided by a BUILD_ID record. The
[kernel.kallsyms] is provided by a MMAP record. There is no clean and
obvious way to link the two, unfortunately.
In regular mode, the kernel buildid is generated from reading the ELF
image or kallsyms and perf knows to associate [kernel.kallsyms] to it.
Later on, when perf processes the [kernel.kallsyms] MMAP record, it will
already have a dso for it.
So for now, make sure perf buildid-list shows the buildids for
everything but the kernel image.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1337081295-10303-6-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In __perf_session__process_pipe_events(), there was a risk we would read
more than what a union perf_event struct can hold. this could happen in
case, perf is reading a file which contains new record types it does not
know about and which are larger than anything it knows about.
In general, perf is supposed to skip records it does not understand, but
in pipe mode, those have to be read and ignored. The fixed size header
contains the size of the record, but that size may be larger than union
perf_event, yet it was used as the backing to the read in:
union perf_event event;
void *p;
size = event->header.size;
p = &event;
p += sizeof(struct perf_event_header);
if (size - sizeof(struct perf_event_header)) {
err = readn(self->fd, p, size - sizeof(struct perf_event_header));
We fix this by allocating a buffer based on the size reported in the
header. We reuse the buffer as much as we can. We realloc in case it
becomes too small. In the common case, the performance impact is
negligible.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1337081295-10303-3-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf inject -b was broken. It would not inject any build_id into the
stream. Furthermore, it would strip samples from the stream.
The reason was a missing initialization of the event attribute
structure. The perf_tool.tool.attr() callback was pointing to a simple
repipe. But there was no initialization of the internal data structures
to keep track of events and event ids. That later caused event id
lookups to fail, and sample would get removed.
The patch simply adds back the call to perf_event__process_attr() to
initialize the evlist structure and now build_ids are again injected.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1337081295-10303-2-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the perf data file is read cross architectures, the
perf_event__attr_swap function takes care about endianness of all the
struct fields except the bitfield flags.
The bitfield flags need to be transformed as well, since the bitfield
binary storage differs for both endians.
ABI says:
Bit-fields are allocated from right to left (least to most significant)
on little-endian implementations and from left to right (most to least
significant) on big-endian implementations.
The above seems to be byte specific, so we need to reverse each byte of
the bitfield. 'Internet' also says this might be implementation specific
and we probably need proper fix and carry perf_event_attr bitfield flags
in separate data file FEAT_ section. Thought this seems to work for now.
Note, running following to test perf endianity handling:
test 1)
- origin system:
# perf record -a -- sleep 10 (any perf record will do)
# perf report > report.origin
# perf archive perf.data
- copy the perf.data, report.origin and perf.data.tar.bz2
to a target system and run:
# tar xjvf perf.data.tar.bz2 -C ~/.debug
# perf report > report.target
# diff -u report.origin report.target
- the diff should produce no output
(besides some white space stuff and possibly different
date/TZ output)
test 2)
- origin system:
# perf record -ag -fo /tmp/perf.data -- sleep 1
- mount origin system root to the target system on /mnt/origin
- target system:
# perf script --symfs /mnt/origin -I -i /mnt/origin/tmp/perf.data \
--kallsyms /mnt/origin/proc/kallsyms
- complete perf.data header is displayed
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337151548-2396-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While migrating to the libtraceevent, the perl scripting engine
missed this structure rename.
This fixes:
util/scripting-engines/trace-event-perl.c: In function "find_cache_event":
util/scripting-engines/trace-event-perl.c:244: error: assignment from incompatible pointer type
util/scripting-engines/trace-event-perl.c:248: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:248: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:250: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c: In function "perl_process_tracepoint":
util/scripting-engines/trace-event-perl.c:286: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:286: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:307: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c: In function "perl_generate_script":
util/scripting-engines/trace-event-perl.c:498: error: passing argument 1 of "trace_find_next_event" from incompatible pointer type
util/scripting-engines/../trace-event.h:56: note: expected "struct event_format *" but argument is of type "struct event *"
util/scripting-engines/trace-event-perl.c:498: error: assignment from incompatible pointer type
util/scripting-engines/trace-event-perl.c:499: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:499: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:513: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:532: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:556: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:569: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:570: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:579: error: dereferencing pointer to incomplete type
util/scripting-engines/trace-event-perl.c:580: error: dereferencing pointer to incomplete type
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/1337697049-30251-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Handle the print argument types brought by the new libparsevent in perl
scripting engine.
PRINT_BSTRING and PRINT_DYNAMIC_ARRAY are treated just like strings
and thus don't require specific processing.
But PRINT_FUNC need specific plugins which are not yet handled, lets
warn if we meet this case.
This fixes:
util/scripting-engines/trace-event-perl.c: In function define_event_symbol:
util/scripting-engines/trace-event-perl.c:188: error: enumeration value PRINT_BSTRING not handled in switch
util/scripting-engines/trace-event-perl.c:188: error: enumeration value PRINT_DYNAMIC_ARRAY not handled in switch
util/scripting-engines/trace-event-perl.c:188: error: enumeration value PRINT_FUNC not handled in switch
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/1337697049-30251-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding a new hardcoded term 'name' allowing to specify a name for the
pmu event. The term is defined along with standard pmu terms. If no
'name' term is given, the event name follows following template:
"raw 0x<perf_event_attr::config>"
running:
perf stat -e cpu/config=1,name=krava1/u ls
will produce following output:
...
Performance counter stats for 'ls':
0 krava1
...
running:
perf stat -e cpu/config=1/u ls
will produce following output:
...
Performance counter stats for 'ls':
0 raw 0x1
...
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337584373-2741-6-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Conflicts:
tools/perf/Makefile
This tree from Frederic unifies the perf and trace-cmd trace event format
parsing code into a single library.
Powertop and other tools will also be able to make use of it.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
764e16a changed perf-record to create events disabled by default and
enable them once perf initializations are done. This setting was dropped
by 0f82ebc. Now perf events are once again generated during perf's
initialization phase (e.g., generating maps).
As an example, perf opens a lot of files at startup. Unpatched:
perf record -e syscalls:sys_enter_open -ga -fo /tmp/perf.data -- sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.087 MB /tmp/perf.data (~3798 samples) ]
Using perf-script to look at the samples shows the perf command generating
563 of the 566 total events.
Patched:
perf record -e syscalls:sys_enter_open -ga -fo /tmp/perf.data -- sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.028 MB /tmp/perf.data (~1206 samples) ]
Using perf-script to look at the samples does not show perf command.
Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1336968088-11531-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Merge reason: We are going to queue up a dependent patch:
"perf tools: Move parse event automated tests to separated object"
That depends on:
commit e7c72d8
perf tools: Add 'G' and 'H' modifiers to event parsing
Conflicts:
tools/perf/builtin-stat.c
Conflicted with the recent 'perf_target' patches when checking the
result of perf_evsel open routines to see if a retry is needed to cope
with older kernels where the exclude guest/host perf_event_attr bits
were not used.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The callchain address is stored as u64. Current code uses following
format string to display callchain address:
"%p\n", (void *)(long)chain->ip
This way we lose upper 32 bits if we report 64 bit addresses in 32 bit
environment. Fixing this to always display whole 64 bits.
Note, running following to test perf endianity handling:
test 1)
- origin system:
# perf record -a -- sleep 10 (any perf record will do)
# perf report > report.origin
# perf archive perf.data
- copy the perf.data, report.origin and perf.data.tar.bz2
to a target system and run:
# tar xjvf perf.data.tar.bz2 -C ~/.debug
# perf report > report.target
# diff -u report.origin report.target
- the diff should produce no output
(besides some white space stuff and possibly different
date/TZ output)
test 2)
- origin system:
# perf record -ag -fo /tmp/perf.data -- sleep 1
- mount origin system root to the target system on /mnt/origin
- target system:
# perf script --symfs /mnt/origin -I -i /mnt/origin/tmp/perf.data \
--kallsyms /mnt/origin/proc/kallsyms
- complete perf.data header is displayed
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337151548-2396-8-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
