Depending on which functions are inlined in util/pmu.c, the snprintf()
calls in perf_pmu__parse_{scale,unit,per_pkg,snapshot}() might trigger a
warning:
util/pmu.c: In function 'pmu_aliases':
util/pmu.c:178:31: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size between 0 and 4095 [-Werror=format-truncation=]
snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
^~
I found this when trying to build perf from Linux 3.16 with gcc 8.
However I can reproduce the problem in mainline if I force
__perf_pmu__new_alias() to be inlined.
Suppress this by using scnprintf() as has been done elsewhere in perf.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20181111184524.fux4taownc6ndbx6@decadent.org.uk
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This program benchmarks concurrent epoll_wait(2) for file descriptors
that are monitored with with EPOLLIN along various semantics, by a
single epoll instance. Such conditions can be found when using
single/combined or multiple queuing when load balancing.
Each thread has a number of private, nonblocking file descriptors,
referred to as fdmap. A writer thread will constantly be writing to the
fdmaps of all threads, minimizing each threads's chances of epoll_wait
not finding any ready read events and blocking as this is not what we
want to stress. Full details in the start of the C file.
Committer testing:
# perf bench
Usage:
perf bench [<common options>] <collection> <benchmark> [<options>]
# List of all available benchmark collections:
sched: Scheduler and IPC benchmarks
mem: Memory access benchmarks
numa: NUMA scheduling and MM benchmarks
futex: Futex stressing benchmarks
epoll: Epoll stressing benchmarks
all: All benchmarks
# perf bench epoll
# List of available benchmarks for collection 'epoll':
wait: Benchmark epoll concurrent epoll_waits
all: Run all futex benchmarks
# perf bench epoll wait
# Running 'epoll/wait' benchmark:
Run summary [PID 19295]: 3 threads monitoring on 64 file-descriptors for 8 secs.
[thread 0] fdmap: 0xdaa650 ... 0xdaa74c [ 328241 ops/sec ]
[thread 1] fdmap: 0xdaa900 ... 0xdaa9fc [ 351695 ops/sec ]
[thread 2] fdmap: 0xdaabb0 ... 0xdaacac [ 381423 ops/sec ]
Averaged 353786 operations/sec (+- 4.35%), total secs = 8
#
Committer notes:
Fix the build on debian:experimental-x-mips, debian:experimental-x-mipsel
and others:
CC /tmp/build/perf/bench/epoll-wait.o
bench/epoll-wait.c: In function 'writerfn':
bench/epoll-wait.c:399:12: error: format '%ld' expects argument of type 'long int', but argument 2 has type 'size_t' {aka 'unsigned int'} [-Werror=format=]
printinfo("exiting writer-thread (total full-loops: %ld)\n", iter);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~
bench/epoll-wait.c:86:31: note: in definition of macro 'printinfo'
do { if (__verbose) { printf(fmt, ## arg); fflush(stdout); } } while (0)
^~~
cc1: all warnings being treated as errors
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com> <jbaron@akamai.com>
Link: http://lkml.kernel.org/r/20181106152226.20883-2-dave@stgolabs.net
Link: http://lkml.kernel.org/r/20181106182349.thdkpvshkna5vd7o@linux-r8p5>
[ Applied above fixup as per Davidlohr's request ]
[ Use inttypes.h to print rlim_t fields, fixing the build on Alpine Linux / musl libc ]
[ Check if eventfd() is available, i.e. if HAVE_EVENTFD is defined ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A new 'perf bench epoll' will use this, and to disable it for older
systems, add a feature test for this API.
This is just a simple program that if successfully compiled, means that
the feature is present, at least at the library level, in a build that
sets the output directory to /tmp/build/perf (using O=/tmp/build/perf),
we end up with:
$ ls -la /tmp/build/perf/feature/test-eventfd*
-rwxrwxr-x. 1 acme acme 8176 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.bin
-rw-rw-r--. 1 acme acme 588 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.d
-rw-rw-r--. 1 acme acme 0 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.make.output
$ ldd /tmp/build/perf/feature/test-eventfd.bin
linux-vdso.so.1 (0x00007fff3bf3f000)
libc.so.6 => /lib64/libc.so.6 (0x00007fa984061000)
/lib64/ld-linux-x86-64.so.2 (0x00007fa984417000)
$ grep eventfd -A 2 -B 2 /tmp/build/perf/FEATURE-DUMP
feature-dwarf=1
feature-dwarf_getlocations=1
feature-eventfd=1
feature-fortify-source=1
feature-sync-compare-and-swap=1
$
The main thing here is that in the end we'll have -DHAVE_EVENTFD in
CFLAGS, and then the 'perf bench' entry needing that API can be
selectively pruned.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-wkeldwob7dpx6jvtuzl8164k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While working on augmented syscalls I got into this error:
# trace -vv --filter-pids 2469,1663 -e tools/perf/examples/bpf/augmented_raw_syscalls.c sleep 1
<SNIP>
libbpf: map 0 is "__augmented_syscalls__"
libbpf: map 1 is "__bpf_stdout__"
libbpf: map 2 is "pids_filtered"
libbpf: map 3 is "syscalls"
libbpf: collecting relocating info for: '.text'
libbpf: relo for 13 value 84 name 133
libbpf: relocation: insn_idx=3
libbpf: relocation: find map 3 (pids_filtered) for insn 3
libbpf: collecting relocating info for: 'raw_syscalls:sys_enter'
libbpf: relo for 8 value 0 name 0
libbpf: relocation: insn_idx=1
libbpf: relo for 8 value 0 name 0
libbpf: relocation: insn_idx=3
libbpf: relo for 9 value 28 name 178
libbpf: relocation: insn_idx=36
libbpf: relocation: find map 1 (__augmented_syscalls__) for insn 36
libbpf: collecting relocating info for: 'raw_syscalls:sys_exit'
libbpf: relo for 8 value 0 name 0
libbpf: relocation: insn_idx=0
libbpf: relo for 8 value 0 name 0
libbpf: relocation: insn_idx=2
bpf: config program 'raw_syscalls:sys_enter'
bpf: config program 'raw_syscalls:sys_exit'
libbpf: create map __bpf_stdout__: fd=3
libbpf: create map __augmented_syscalls__: fd=4
libbpf: create map syscalls: fd=5
libbpf: create map pids_filtered: fd=6
libbpf: added 13 insn from .text to prog raw_syscalls:sys_enter
libbpf: added 13 insn from .text to prog raw_syscalls:sys_exit
libbpf: load bpf program failed: Operation not permitted
libbpf: failed to load program 'raw_syscalls:sys_exit'
libbpf: failed to load object 'tools/perf/examples/bpf/augmented_raw_syscalls.c'
bpf: load objects failed: err=-4009: (Incorrect kernel version)
event syntax error: 'tools/perf/examples/bpf/augmented_raw_syscalls.c'
\___ Failed to load program for unknown reason
(add -v to see detail)
Run 'perf list' for a list of valid events
Usage: perf trace [<options>] [<command>]
or: perf trace [<options>] -- <command> [<options>]
or: perf trace record [<options>] [<command>]
or: perf trace record [<options>] -- <command> [<options>]
-e, --event <event> event/syscall selector. use 'perf list' to list available events
If I then try to use strace (perf trace'ing 'perf trace' needs some more work
before its possible) to get a bit more info I get:
# strace -e bpf trace --filter-pids 2469,1663 -e tools/perf/examples/bpf/augmented_raw_syscalls.c sleep 1
bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_PERF_EVENT_ARRAY, key_size=4, value_size=4, max_entries=4, map_flags=0, inner_map_fd=0, map_name="__bpf_stdout__", map_ifindex=0}, 72) = 3
bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_PERF_EVENT_ARRAY, key_size=4, value_size=4, max_entries=4, map_flags=0, inner_map_fd=0, map_name="__augmented_sys", map_ifindex=0}, 72) = 4
bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_ARRAY, key_size=4, value_size=1, max_entries=500, map_flags=0, inner_map_fd=0, map_name="syscalls", map_ifindex=0}, 72) = 5
bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_HASH, key_size=4, value_size=1, max_entries=512, map_flags=0, inner_map_fd=0, map_name="pids_filtered", map_ifindex=0}, 72) = 6
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_TRACEPOINT, insn_cnt=57, insns=0x1223f50, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_enter", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = 7
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_TRACEPOINT, insn_cnt=18, insns=0x1224120, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_exit", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = -1 EPERM (Operation not permitted)
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_TRACEPOINT, insn_cnt=18, insns=0x1224120, license="GPL", log_level=1, log_size=262144, log_buf="", kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_exit", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = -1 EPERM (Operation not permitted)
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_KPROBE, insn_cnt=18, insns=0x1224120, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_exit", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = -1 EPERM (Operation not permitted)
event syntax error: 'tools/perf/examples/bpf/augmented_raw_syscalls.c'
\___ Failed to load program for unknown reason
<SNIP similar output as without 'strace'>
#
I managed to create the maps, etc, but then installing the "sys_exit" hook into
the "raw_syscalls:sys_exit" tracepoint somehow gets -EPERMed...
I then go and try reducing the size of this new table:
+++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c
@@ -47,6 +47,17 @@ struct augmented_filename {
#define SYS_OPEN 2
#define SYS_OPENAT 257
+struct syscall {
+ bool filtered;
+};
+
+struct bpf_map SEC("maps") syscalls = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(int),
+ .value_size = sizeof(struct syscall),
+ .max_entries = 500,
+};
And after reducing that .max_entries a tad, it works. So yeah, the "unknown
reason" should be related to the number of bytes all this is taking, reduce the
default for pid_map()s so that we can have a "syscalls" map with enough slots
for all syscalls in most arches. And take notes about this error message,
improve it :-)
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-yjzhak8asumz9e9hts2dgplp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Lookup for the first map named "filtered_pids" and, if augmenting
syscalls, i.e. if a BPF event is present and the
"__augmented_syscalls__" is present, then fill in that map with the pids
to filter, be it feedback loop ones (perf trace's pid, its father if it
is "sshd", more auto-filtered in the future) or the ones explicitely
stated in the tool command line via --filter-pids.
The code to actually fill in the map comes next.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-rhzytmw7qpe6lqyjxi1ded9t@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When reporting on 'record' server we try to retrieve/use the mnt
namespace of the profiled tasks. We use following API with cookie to
hold the return namespace, roughly:
nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc)
setns(newns, 0);
...
new ns related open..
...
nsinfo__mountns_exit(struct nscookie *nc)
setns(nc->oldns)
Once finished we setns to old namespace, which also sets the current
working directory (cwd) to "/", trashing the cwd we had.
This is mostly fine, because we use absolute paths almost everywhere,
but it screws up 'perf diff':
# perf diff
failed to open perf.data: No such file or directory (try 'perf record' first)
...
Adding the current working directory to be part of the cookie and
restoring it in the nsinfo__mountns_exit call.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 843ff37bb5 ("perf symbols: Find symbols in different mount namespace")
Link: http://lkml.kernel.org/r/20181101170001.30019-1-jolsa@kernel.org
[ No need to check for NULL args for free(), use zfree() for struct members ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adam reported a record command crash for simple session like:
$ perf record -e cpu-clock ls
with following backtrace:
Program received signal SIGSEGV, Segmentation fault.
3543 ev = event_update_event__new(size + 1, PERF_EVENT_UPDATE__UNIT, evsel->id[0]);
(gdb) bt
#0 perf_event__synthesize_event_update_unit
#1 0x000000000051e469 in perf_event__synthesize_extra_attr
#2 0x00000000004445cb in record__synthesize
#3 0x0000000000444bc5 in __cmd_record
...
We synthesize an update event that needs to touch the evsel id array,
which is not defined at that time. Fix this by forcing the id allocation
for events with their unit defined.
Reflecting possible read_format ID bit in the attr tests.
Reported-by: Yongxin Liu <yongxin.liu@outlook.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adam Lee <leeadamrobert@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201477
Fixes: bfd8f72c27 ("perf record: Synthesize unit/scale/... in event update")
Link: http://lkml.kernel.org/r/20181112130012.5424-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/urgent improvements and fixes from Arnaldo Carvalho de Melo:
Intel PT SQL viewer: (Adrian Hunter)
- Fall back to /usr/local/lib/libxed.so
- Add Selected branches report
- Add help window
- Fix table find when table re-ordered
Intel PT debug log (Adrian Hunter)
- Add more event information
- Add MTC and CYC timestamps
perf record: (Andi Kleen)
- Support weak groups, just like with 'perf stat'
perf trace: (Arnaldo Carvalho de Melo)
- Start augmenting raw_syscalls:{sys_enter,sys_exit}: goal is to have a
generic, arch independent eBPF kernel component that is programmed with
syscall table details, what to copy, how many bytes, pid, arg filters from the
userspace via eBPF maps by the 'perf trace' tool that continues to use all its
argument beautifiers, just taking advantage of the extra pointer contents.
JVMTI: (Gustavo Romero)
- Fix undefined symbol scnprintf in libperf-jvmti.so
perf top: (Jin Yao)
- Display the LBR stats in callchain entries
perf stat: (Thomas Richter)
- Handle different PMU names with common prefix
arm64: Will (Deacon)
- Fix arm64 tools build failure wrt smp_load_{acquire,release}.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is the commit that porting the perf for nds32.
1.Raw event:
The raw events start with 'r'.
Usage:
perf stat -e rXYZ ./app
X: the index of performance counter.
YZ: the index(convert to hexdecimal) of events
Example:
'perf stat -e r101 ./app' means the counter 1 will count the instruction
event.
The index of counter and events can be found in
"Andes System Privilege Architecture Version 3 Manual".
Or you can perform the 'perf list' to find the symbolic name of raw events.
2.Perf mmap2:
Fix unexpected perf mmap2() page fault
When the mmap2() called by perf application,
you will encounter such condition:"failed to write."
With return value -EFAULT
This is due to the page fault caused by "reading" buffer
from the mapped legal address region to write to the descriptor.
The page_fault handler will get a VM_FAULT_SIGBUS return value,
which should not happens here.(Due to this is a read request.)
You can refer to kernel/events/core.c:perf_mmap_fault(...)
If "(vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE))" is evaluated
as true, you will get VM_FAULT_SIGBUS as return value.
However, this is not an write request. The flags which indicated
why the page fault happens is wrong.
Furthermore, NDS32 SPAv3 is not able to detect it is read or write.
It only know either it is instruction fetch or data access.
Therefore, by removing the wrong flag assignment(actually, the hardware
is not able to show the reason), we can fix this bug.
3.Perf multiple events map to same counter.
When there are multiple events map to the same counter, the counter
counts inaccurately. This is because each counter only counts one event
in the same time.
So when there are multiple events map to same counter, they have to take
turns in each context.
There are two solution:
1. Print the error message when multiple events map to the same counter.
But print the error message would let the program hang in loop. The ltp
(linux test program) would be failed when the program hang in loop.
2. Don't print the error message, the ltp would pass. But the user need to
have the knowledge that don't count the events which map to the same
counter, or the user will get the inaccurate results.
We choose method 2 for the solution
Signed-off-by: Nickhu <nickhu@andestech.com>
Acked-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Currently jvmti agent can not be used because function scnprintf is not
present in the agent libperf-jvmti.so. As a result the JVM when using
such agent to record JITed code profiling information will fail on
looking up scnprintf:
java: symbol lookup error: lib/libperf-jvmti.so: undefined symbol: scnprintf
This commit fixes that by reverting to the use of snprintf, that can be
looked up, instead of scnprintf, adding a proper check for the returned
value in order to print a better error message when the jitdump file
pathname is too long. Checking the returned value also helps to comply
with some recent gcc versions, like gcc8, which will fail due to
truncated writing checks related to the -Werror=format-truncation= flag.
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
LPU-Reference: 1541117601-18937-2-git-send-email-gromero@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-mvpxxxy7wnzaj74cq75muw3f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Guenter reported that using ARCH=x86_64 to build perf has regressed:
$ make -C tools/perf O=/tmp/build/perf ARCH=x86_64
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j4' parallel build
HOSTCC /tmp/build/perf/fixdep.o
HOSTLD /tmp/build/perf/fixdep-in.o
LINK /tmp/build/perf/fixdep
Auto-detecting system features:
... dwarf: [ on ]
<SNIP>
... bpf: [ on ]
GEN /tmp/build/perf/common-cmds.h
make[2]: *** No rule to make target '/home/acme/git/perf/tools/arch/x86_64/include/uapi/asm//mman.h', needed by '/tmp/build/perf/trace/beauty/generated/mmap_flags_array.c'. Stop.
make[2]: *** Waiting for unfinished jobs....
PERF_VERSION = 4.19.gf6c23e3
make[1]: *** [Makefile.perf:207: sub-make] Error 2
make: *** [Makefile:70: all] Error 2
make: Leaving directory '/home/acme/git/perf/tools/perf'
$
This is because we must use $(SRCARCH) where we were using $(ARCH), so
that, just like the top level Makefile, we get this done:
# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
SRCARCH := x86
endif
ifeq ($(ARCH),x86_64)
SRCARCH := x86
endif
Which is done in tools/scripts/Makefile.arch, so switch to use
$(SRCARCH).
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: fbd7458db7 ("perf beauty: Wire up the mmap flags table generator to the Makefile")
Link: https://lkml.kernel.org/r/20181105184612.GD7077@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On s390 the CPU Measurement Facility for counters now supports
2 PMUs named cpum_cf (CPU Measurement Facility for counters) and
cpum_cf_diag (CPU Measurement Facility for diagnostic counters)
for one and the same CPU.
Running command
[root@s35lp76 perf]# ./perf stat -e tx_c_tend \
-- ~/mytests/cf-tx-events 1
Measuring transactions
TX_C_TABORT_NO_SPECIAL: 0 expected:0
TX_C_TABORT_SPECIAL: 0 expected:0
TX_C_TEND: 1 expected:1
TX_NC_TABORT: 11 expected:11
TX_NC_TEND: 1 expected:1
Performance counter stats for '/root/mytests/cf-tx-events 1':
2 tx_c_tend
0.002120091 seconds time elapsed
0.000121000 seconds user
0.002127000 seconds sys
[root@s35lp76 perf]#
displays output which is unexpected (and wrong):
2 tx_c_tend
The test program definitely triggers only one transaction, as shown
in line 'TX_C_TEND: 1 expected:1'.
This is caused by the following call sequence:
pmu_lookup() scans and installs a PMU.
+--> pmu_aliases() parses all aliases in directory
.../<pmu-name>/events/* which are file names.
+--> pmu_aliases_parse() Read each file in directory and create
an new alias entry. This is done with
+--> perf_pmu__new_alias() and
+--> __perf_pmu__new_alias() which also check for
identical alias names.
After pmu_aliases() returns, a complete list of event names
for this pmu has been created. Now function
pmu_add_cpu_aliases() is called to add the events listed in the json
| files to the alias list of the cpu.
+--> perf_pmu__find_map() Returns a pointer to the json events.
Now function pmu_add_cpu_aliases() scans through all events listed
in the JSON files for this CPU.
Each json event pmu name is compared with the current PMU being
built up and if they mismatch, the json event is added to the
current PMUs alias list.
To avoid duplicate entries the following comparison is done:
if (!is_arm_pmu_core(name)) {
pname = pe->pmu ? pe->pmu : "cpu";
if (strncmp(pname, name, strlen(pname)))
continue;
}
The culprit is the strncmp() function.
Using current s390 PMU naming, the first PMU is 'cpum_cf'
and a long list of events is added, among them 'tx_c_tend'
When the second PMU named 'cpum_cf_diag' is added, only one event
named 'CF_DIAG' is added by the pmu_aliases() function.
Now function pmu_add_cpu_aliases() is invoked for PMU 'cpum_cf_diag'.
Since the CPUID string is the same for both PMUs, json file events
for PMU named 'cpum_cf' are added to the PMU 'cpm_cf_diag'
This happens because the strncmp() actually compares:
strncmp("cpum_cf", "cpum_cf_diag", 6);
The first parameter is the pmu name taken from the event in
the json file. The second parameter is the pmu name of the PMU
currently being built.
They are different, but the length of the compare only tests the
common prefix and this returns 0(true) when it should return false.
Now all events for PMU cpum_cf are added to the alias list for pmu
cpum_cf_diag.
Later on in function parse_events_add_pmu() the event 'tx_c_end' is
searched in all available PMUs and found twice, adding it two
times to the evsel_list global variable which is the root
of all events. This results in a counter value of 2 instead
of 1.
Output with this patch:
[root@s35lp76 perf]# ./perf stat -e tx_c_tend \
-- ~/mytests/cf-tx-events 1
Measuring transactions
TX_C_TABORT_NO_SPECIAL: 0 expected:0
TX_C_TABORT_SPECIAL: 0 expected:0
TX_C_TEND: 1 expected:1
TX_NC_TABORT: 11 expected:11
TX_NC_TEND: 1 expected:1
Performance counter stats for '/root/mytests/cf-tx-events 1':
1 tx_c_tend
0.001815365 seconds time elapsed
0.000123000 seconds user
0.001756000 seconds sys
[root@s35lp76 perf]#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Sebastien Boisvert <sboisvert@gydle.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 292c34c102 ("perf pmu: Fix core PMU alias list for X86 platform")
Link: http://lkml.kernel.org/r/20181023151616.78193-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Implement a weak group fallback for 'perf record', similar to the
existing 'perf stat' support. This allows to use groups that might be
longer than the available counters without failing.
Before:
$ perf record -e '{cycles,cache-misses,cache-references,cpu_clk_unhalted.thread,cycles,cycles,cycles}' -a sleep 1
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles).
/bin/dmesg | grep -i perf may provide additional information.
After:
$ ./perf record -e '{cycles,cache-misses,cache-references,cpu_clk_unhalted.thread,cycles,cycles,cycles}:W' -a sleep 1
WARNING: No sample_id_all support, falling back to unordered processing
[ perf record: Woken up 3 times to write data ]
[ perf record: Captured and wrote 8.136 MB perf.data (134069 samples) ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181001195927.14211-2-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is the start of having the raw_syscalls:sys_enter BPF handler
collecting pointer arguments, namely pathnames, and with two syscalls
that have that pointer in different arguments, "open" as it as its first
argument, "openat" as the second.
With this in place the existing beautifiers in 'perf trace' works, those
args are shown instead of just the pointer that comes with the syscalls
tracepoints.
This also serves to show and document pitfalls in the process of using
just that place in the kernel (raw_syscalls:sys_enter) plus tables
provided by userspace to collect syscall pointer arguments.
One is the need to use a barrier, as suggested by Edward, to avoid clang
optimizations that make the kernel BPF verifier to refuse loading our
pointer contents collector.
The end result should be a generic eBPF program that works in all
architectures, with the differences amongst archs resolved by the
userspace component, 'perf trace', that should get all its tables
created automatically from the kernel components where they are defined,
via string table constructors for things not expressed in BTF/DWARF
(enums, structs, etc), and otherwise using those observability files
(BTF).
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-37dz54pmotgpnwg9tb6zuk9j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf updates and fixes from Ingo Molnar:
"These are almost all tooling updates: 'perf top', 'perf trace' and
'perf script' fixes and updates, an UAPI header sync with the merge
window versions, license marker updates, much improved Sparc support
from David Miller, and a number of fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
perf intel-pt/bts: Calculate cpumode for synthesized samples
perf intel-pt: Insert callchain context into synthesized callchains
perf tools: Don't clone maps from parent when synthesizing forks
perf top: Start display thread earlier
tools headers uapi: Update linux/if_link.h header copy
tools headers uapi: Update linux/netlink.h header copy
tools headers: Sync the various kvm.h header copies
tools include uapi: Update linux/mmap.h copy
perf trace beauty: Use the mmap flags table generated from headers
perf beauty: Wire up the mmap flags table generator to the Makefile
perf beauty: Add a generator for MAP_ mmap's flag constants
tools include uapi: Update asound.h copy
tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
tools include uapi: Update linux/fs.h copy
perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
perf cs-etm: Correct CPU mode for samples
perf unwind: Take pgoff into account when reporting elf to libdwfl
perf top: Do not use overwrite mode by default
perf top: Allow disabling the overwrite mode
perf trace: Beautify mount's first pathname arg
...
For now with BPF raw_augmented we hook into raw_syscalls:sys_enter and
there we get all 6 syscall args plus the tracepoint common fields
(sizeof(long)) and the syscall_nr (another long). So we check if that is
the case and if so don't look after the sc->args_size, but always after
the full raw_syscalls:sys_enter payload, which is fixed.
We'll revisit this later to pass s->args_size to the BPF augmenter (now
tools/perf/examples/bpf/augmented_raw_syscalls.c, so that it copies only
what we need for each syscall, like what happens when we use
syscalls:sys_enter_NAME, so that we reduce the kernel/userspace traffic
to just what is needed for each syscall.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-nlslrg8apxdsobt4pwl3n7ur@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When synthesizing FORK events, we are trying to create thread objects
for the already running tasks on the machine.
Normally, for a kernel FORK event, we want to clone the parent's maps
because that is what the kernel just did.
But when synthesizing, this should not be done. If we do, we end up
with overlapping maps as we process the sythesized MMAP2 events that
get delivered shortly thereafter.
Use the FORK event misc flags in an internal way to signal this
situation, so we can elide the map clone when appropriate.
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Link: http://lkml.kernel.org/r/20181030.222404.2085088822877051075.davem@davemloft.net
[ Added comment about flag use in machine__process_fork_event(),
use ternary op in thread__clone_map_groups() as suggested by Jiri ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If events are coming in at a rate such that the event processing thread
can barely keep up, our initial run of the event ring will almost never
terminate and this delays the starting of the display thread.
The screen basically stays black until the event thread can get out of
it's endless loop.
Therefore, start the display thread before we start processing the ring
buffer.
This also make sure that we always have the user requested real time
setting engaged when processing the ring.
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20181030.223003.2242527041807905962.davem@davemloft.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
