We'll continue reading its details from tracefs as we need it, but
preallocate the whole thing otherwise we may realloc and end up with
pointers to the previous buffer.
I.e. in an upcoming algorithm we'll look for syscalls that have function
signatures that are similar to a given syscall to see if we can reuse
its BPF augmenter, so we may be at syscall 42, having a 'struct syscall'
pointing to that slot in trace->syscalls.table[] and try to read the
slot for an yet unread syscall, which would realloc that table to read
the info for syscall 43, say, which would trigger a realoc of
trace->syscalls.table[], and then the pointer we had for syscall 42
would be pointing to the previous block of memory. b00m.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-m3cjzzifibs13imafhkk77a0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With BPF_MAP_TYPE_PROG_ARRAY + bpf_tail_call() we want to have BPF
programs, i.e. functions in a object file that perf's BPF loader
shouldn't try to attach to anything, i.e. "!syscalls:sys_enter_open"
should just stay there, not be attached to a tracepoint with that name,
it'll be used by, for instance, 'perf trace' to associate with syscalls
that copy, in addition to the syscall raw args, a filename pointed by
the first arg, i.e. multiple syscalls that need copying the same pointer
arg in the same way, as a filename, for instance, will share the same
BPF program/function.
Right now when perf's BPF loader sees a function with a name
"sys:name" it'll look for a tracepoint and will associate that BPF
program with it, say:
SEC("raw_syscalls:sys_enter")
int sys_enter(struct syscall_enter_args *args)
{
//SNIP
}
Will crate a perf_evsel tracepoint event and then associate with it that
BPF program.
This convention at some point will switch to the one used by the BPF
loader in libbpf, but to experiment with BPF_MAP_TYPE_PROG_ARRAY in
'perf trace' lets do this, that will not require changing too much
stuff.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-lk6dasjr1yf9rtvl292b2hpc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When building our local version of perf with MSAN (Memory Sanitizer) and
running the perf record command, MSAN throws a use of uninitialized
value warning in "tools/perf/util/util.c:333:6".
This warning stems from the "buf" variable being passed into "write".
It originated as the variable "ev" with the type union perf_event*
defined in the "perf_event__synthesize_attr" function in
"tools/perf/util/header.c".
In the "perf_event__synthesize_attr" function they allocate space with a malloc
call using ev, then go on to only assign some of the member variables before
passing "ev" on as a parameter to the "process" function therefore "ev"
contains uninitialized memory. Changing the malloc call to zalloc to initialize
all the members of "ev" which gets rid of the warning.
To reproduce this warning, build perf by running:
make -C tools/perf CLANG=1 CC=clang EXTRA_CFLAGS="-fsanitize=memory\
-fsanitize-memory-track-origins"
(Additionally, llvm might have to be installed and clang might have to
be specified as the compiler - export CC=/usr/bin/clang)
then running:
tools/perf/perf record -o - ls / | tools/perf/perf --no-pager annotate\
-i - --stdio
Please see the cover letter for why false positive warnings may be
generated.
Signed-off-by: Numfor Mbiziwo-Tiapo <nums@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Drayton <mbd@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20190724234500.253358-2-nums@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
perf.data:
Alexey Budankov:
- Fix loading of compressed data split across adjacent records
Jiri Olsa:
- Fix buffer size setting for processing CPU topology perf.data header.
perf stat:
Jiri Olsa:
- Fix segfault for event group in repeat mode
Cong Wang:
- Always separate "stalled cycles per insn" line, it was being appended to
the "instructions" line.
perf script:
Andi Kleen:
- Fix --max-blocks man page description.
- Improve man page description of metrics.
- Fix off by one in brstackinsn IPC computation.
perf probe:
Arnaldo Carvalho de Melo:
- Avoid calling freeing routine multiple times for same pointer.
perf build:
- Do not use -Wshadow on gcc < 4.8, avoiding too strict warnings
treated as errors, breaking the build.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So that, when perf_add_probe_events() fails, like in:
# perf probe icmp_rcv:64 "type=icmph->type"
Failed to find 'icmph' in this function.
Error: Failed to add events.
Segmentation fault (core dumped)
#
We don't segfault.
clear_perf_probe_event() was zeroing the whole pev, and since the switch
to zfree() for the members in the pev, that memset() was removed, which
left nargs with its original value, in the above case 1.
With the memset the same pev could be passed to clear_perf_probe_event()
multiple times, since all it would have would be zeroes, and free()
accepts zero, the loop would not happen and we would just memset it
again to zeroes.
Without it we got that segfault, so zero nargs to keep it like it was,
next cset will avoid calling clear_perf_probe_event() for the same pevs
in case of failure.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: d8f9da2404 ("perf tools: Use zfree() where applicable")
Link: https://lkml.kernel.org/n/tip-802f2jypnwqsvyavvivs8464@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix decompression failure found during the loading of compressed trace
collected on larger scale systems (>48 cores).
The error happened due to lack of decompression space for a mmaped
buffer data chunk split across adjacent PERF_RECORD_COMPRESSED records.
$ perf report -i bt.16384.data --stats
failed to decompress (B): 63869 -> 0 : Destination buffer is too small
user stack dump failure
Can't parse sample, err = -14
0x2637e436 [0x4080]: failed to process type: 9
Error:
failed to process sample
$ perf test 71
71: Zstd perf.data compression/decompression : Ok
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/4d839e1b-9c48-89c4-9702-a12217420611@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The "stalled cycles per insn" is appended to "instructions" when the CPU
has this hardware counter directly. We should always make it a separate
line, which also aligns to the output when we hit the "if (total &&
avg)" branch.
Before:
$ sudo perf stat --all-cpus --field-separator , --log-fd 1 -einstructions,cycles -- sleep 1
4565048704,,instructions,64114578096,100.00,1.34,insn per cycle,,
3396325133,,cycles,64146628546,100.00,,
After:
$ sudo ./tools/perf/perf stat --all-cpus --field-separator , --log-fd 1 -einstructions,cycles -- sleep 1
6721924,,instructions,24026790339,100.00,0.22,insn per cycle
,,,,,0.00,stalled cycles per insn
30939953,,cycles,24025512526,100.00,,
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/20190517221039.8975-1-xiyou.wangcong@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Numfor Mbiziwo-Tiapo reported segfault on stat of event group in repeat
mode:
# perf stat -e '{cycles,instructions}' -r 10 ls
It's caused by memory corruption due to not cleaned evsel's id array and
index, which needs to be rebuilt in every stat iteration. Currently the
ids index grows, while the array (which is also not freed) has the same
size.
Fixing this by releasing id array and zeroing ids index in
perf_evsel__close function.
We also need to keep the evsel_list alive for stat record (which is
disabled in repeat mode).
Reported-by: Numfor Mbiziwo-Tiapo <nums@google.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Drayton <mbd@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20190715142121.GC6032@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf tooling updates from Thomas Gleixner:
"A set of perf improvements and fixes:
perf db-export:
- Improvements in how COMM details are exported to databases for post
processing and use in the sql-viewer.py UI.
- Export switch events to the database.
BPF:
- Bump rlimit(MEMLOCK) for 'perf test bpf' and 'perf trace', just
like selftests/bpf/bpf_rlimit.h do, which makes errors due to
exhaustion of this limit, which are kinda cryptic (EPERM sometimes)
less frequent.
perf version:
- Fix segfault due to missing OPT_END(), noticed on PowerPC.
perf vendor events:
- Add JSON files for IBM s/390 machine type 8561.
perf cs-etm (ARM):
- Fix two cases of error returns not bing done properly: Invalid
ERR_PTR() use and loss of propagation error codes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
perf version: Fix segfault due to missing OPT_END()
perf vendor events s390: Add JSON files for machine type 8561
perf cs-etm: Return errcode in cs_etm__process_auxtrace_info()
perf cs-etm: Remove errnoeous ERR_PTR() usage in cs_etm__process_auxtrace_info
perf scripts python: export-to-postgresql.py: Export switch events
perf scripts python: export-to-sqlite.py: Export switch events
perf db-export: Export switch events
perf db-export: Factor out db_export__threads()
perf script: Add scripting operation process_switch()
perf scripts python: exported-sql-viewer.py: Use new 'has_calls' column
perf scripts python: exported-sql-viewer.py: Remove redundant semi-colons
perf scripts python: export-to-postgresql.py: Add has_calls column to comms table
perf scripts python: export-to-sqlite.py: Add has_calls column to comms table
perf db-export: Also export thread's current comm
perf db-export: Factor out db_export__comm()
perf scripts python: export-to-postgresql.py: Export comm details
perf scripts python: export-to-sqlite.py: Export comm details
perf db-export: Export comm details
perf db-export: Fix a white space issue in db_export__sample()
perf db-export: Move export__comm_thread into db_export__sample()
...
Pull tracing updates from Steven Rostedt:
"The main changes in this release include:
- Add user space specific memory reading for kprobes
- Allow kprobes to be executed earlier in boot
The rest are mostly just various clean ups and small fixes"
* tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
tracing: Make trace_get_fields() global
tracing: Let filter_assign_type() detect FILTER_PTR_STRING
tracing: Pass type into tracing_generic_entry_update()
ftrace/selftest: Test if set_event/ftrace_pid exists before writing
ftrace/selftests: Return the skip code when tracing directory not configured in kernel
tracing/kprobe: Check registered state using kprobe
tracing/probe: Add trace_event_call accesses APIs
tracing/probe: Add probe event name and group name accesses APIs
tracing/probe: Add trace flag access APIs for trace_probe
tracing/probe: Add trace_event_file access APIs for trace_probe
tracing/probe: Add trace_event_call register API for trace_probe
tracing/probe: Add trace_probe init and free functions
tracing/uprobe: Set print format when parsing command
tracing/kprobe: Set print format right after parsed command
kprobes: Fix to init kprobes in subsys_initcall
tracepoint: Use struct_size() in kmalloc()
ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS
ftrace: Enable trampoline when rec count returns back to one
tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline
tracing: Make a separate config for trace event self tests
...
