This will work similar to the syscall args, we'll allocate an array
of 'struct syscall_arg_fmt' for the tracepoint args and then init them
using the same algorithm used for the defaults for syscall args, i.e.
using its types and sometimes names as hints to find the right scnprintf
routine to beautify them from numbers into strings.
Next step is to stop using libtracevent to printf tracepoints, as we'll
have more beautifiers than int provides, modulo perhaps some plugins.
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-dcl135relxvf6ljisjg13aqg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When not using augmented syscalls, i.e. not passing thru the command
line a eBPF source or object file event that provides the
__augmented_syscalls__ BPF_MAP_TYPE_PERF_EVENT_ARRAY, etc, as with:
perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c
or passing that augmented eBPF source/object via the trace.add_events in
.perfconfig file, we were assuming that syscalls were asked for,
differing from when not using augmented syscalls at all.
This is confusing when using .perfconfig to hide the fact we're using
the augmenter, i.e. using:
# perf trace -e sched:* sleep 1
Will show both the scheduler tracepoints and the syscalls, where what we
want is to show just the scheduler tracepoints.
To see the scheduler tracepoints and some specific syscall strace-like
formatting, one has to use:
# perf trace -e sched:*,nanosleep sleep 1
Or, if wanting all the syscalls:
# perf trace -e sched:* --syscalls sleep 1
This way 'perf trace' can be used to trace just a set of tracepoints
while allowing for mixing with strace-like when desired, by simply
adding to the mix the name of the syscalls to show in addition to the
tracepoints.
Fix it so that the behaviour using the eBPF based syscall augmenter is
the same as when not using one.
Testing:
Before this patch, with this ~/.perfconfig:
# egrep -B1 ^[[:space:]]+add_events ~/.perfconfig
[trace]
add_events = /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
#
That points to this pre-compiled eBPF syscall augmenter:
# file /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
/home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o: ELF 64-bit LSB relocatable, eBPF, version 1 (SYSV), with debug_info, not stripped
And when asking for _only_ sched:sched_switch and sched:sched_wakeup we
were unconditionally getting all the syscalls formatted strace-like:
# perf trace -e sched:*switch,sched:*wakeup sleep 1 |& tail
0.633 fstat(3, 0x7fe11d030ac0) = 0
0.635 mmap(NULL, 217750512, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe10fec5000
0.643 close(3) = 0
0.668 nanosleep(0x7fff649a3a90, NULL) ...
0.672 sched:sched_switch:prev_comm=sleep prev_pid=4417 prev_prio=120 prev_state=S ==> next_comm=swapper/6 next_pid=0 next_prio=120
1000.822 sched:sched_wakeup:comm=sleep pid=4417 prio=120 target_cpu=006
0.668 ... [continued]: nanosleep()) = 0
1000.923 close(1) = 0
1000.941 close(2) = 0
1000.974 exit_group(0) = ?
#
After the patch:
# perf trace -e sched:*switch,sched:*wakeup sleep 1
0.000 sched:sched_wakeup:comm=perf pid=5529 prio=120 target_cpu=005
1.186 sched:sched_switch:prev_comm=sleep prev_pid=5529 prev_prio=120 prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
1001.573 sched:sched_wakeup:comm=sleep pid=5529 prio=120 target_cpu=005
#
If we add the "open*" syscalls to the mix then the eBPF augmented _will_
be used and these syscalls will be traced together with the specified
sched tracepoints:
# cd /sys/kernel/debug/tracing/events/syscalls/
# ls -1d sys_enter_open*
sys_enter_open
sys_enter_openat
sys_enter_open_by_handle_at
sys_enter_open_tree
#
# perf trace -e open*,sched:*switch,sched:*wakeup sleep 1
0.000 sched:sched_wakeup:comm=perf pid=5580 prio=120 target_cpu=005
0.590 openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
0.616 openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
0.846 openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
0.891 sched:sched_switch:prev_comm=sleep prev_pid=5580 prev_prio=120 prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
1001.005 sched:sched_wakeup:comm=sleep pid=5580 prio=120 target_cpu=005
#
And as we can see, the pathnames were collected via the eBPF augmenters.
If we don't specify anything it'll trace all syscalls:
# perf trace sleep 1 |& tail
0.299 brk(0x5597543a3000) = 0x5597543a3000
0.302 brk(NULL) = 0x5597543a3000
0.307 openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
0.313 fstat(3, 0x7feece50cac0) = 0
0.315 mmap(NULL, 217750512, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7feec13a1000
0.323 close(3) = 0
0.354 nanosleep(0x7ffe338856e0, NULL) = 0
1000.641 close(1) = 0
1000.655 close(2) = 0
1000.673 exit_group(0) = ?
#
Ditto if we don't use .perfconfig's trace.add_events but instead pass
just the augmenter as a command line event:
# vim ~/.perfconfig
# egrep -B1 ^[[:space:]]+add_events ~/.perfconfig
# perf trace -e /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o sleep 1 |& tail
0.294 brk(0x55ae08ec3000) = 0x55ae08ec3000
0.297 brk(NULL) = 0x55ae08ec3000
0.302 openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
0.309 fstat(3, 0x7f726488fac0) = 0
0.311 mmap(NULL, 217750512, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f7257724000
0.319 close(3) = 0
0.347 nanosleep(0x7ffe23643a70, NULL) = 0
1000.560 close(1) = 0
1000.575 close(2) = 0
1000.593 exit_group(0) = ?
#
As well as that + some syscall names for strace-like formatting:
# perf trace -e socket,connect,/home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o ssh localhost
0.000 socket(PF_LOCAL, SOCK_STREAM|CLOEXEC|NONBLOCK, 0) = 3
0.021 connect(3, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
0.034 socket(PF_LOCAL, SOCK_STREAM|CLOEXEC|NONBLOCK, 0) = 3
0.041 connect(3, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
0.163 socket(PF_LOCAL, SOCK_STREAM, 0) = 4
0.185 connect(4, { .family: PF_LOCAL, path: /var/lib/sss/pipes/nss }, 110) = 0
0.670 socket(PF_LOCAL, SOCK_STREAM|CLOEXEC|NONBLOCK, 0) = 7
0.684 connect(7, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
0.694 socket(PF_LOCAL, SOCK_STREAM|CLOEXEC|NONBLOCK, 0) = 7
0.701 connect(7, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
0.994 socket(PF_LOCAL, SOCK_STREAM|CLOEXEC|NONBLOCK, 0) = 5
1.006 connect(5, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
1.014 socket(PF_LOCAL, SOCK_STREAM|CLOEXEC|NONBLOCK, 0) = 5
1.022 connect(5, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
1.068 socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 5
1.087 connect(5, { .family: PF_INET, port: 22, addr: 127.0.0.1 }, 16) = 0
24.299 socket(PF_LOCAL, SOCK_STREAM, 0) = 6
24.337 connect(6, { .family: PF_LOCAL, path: /var/run/.heim_org.h5l.kcm-socket }, 110) = 0
28.441 socket(PF_LOCAL, SOCK_STREAM, 0) = 6
28.516 connect(6, { .family: PF_LOCAL, path: /var/run/.heim_org.h5l.kcm-socket }, 110) = 0
root@localhost's password:^C
#
Everything works without augmenters:
# egrep -B1 ^[[:space:]]+add_events ~/.perfconfig
# perf trace sleep 1 |& tail
0.261 brk(0x5635068ac000) = 0x5635068ac000
0.264 brk(NULL) = 0x5635068ac000
0.268 openat(AT_FDCWD, 0xdce642a0, O_RDONLY|O_CLOEXEC) = 3
0.275 fstat(3, 0x7f3fdce97ac0) = 0
0.277 mmap(NULL, 217750512, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f3fcfd2c000
0.284 close(3) = 0
0.310 nanosleep(0x7ffdaea6ecd0, NULL) = 0
1000.552 close(1) = 0
1000.565 close(2) = 0
1000.580 exit_group(0) = ?
#
# perf trace -e connect ssh localhost
0.000 connect(3, 0x58266930, 110) = -1 ENOENT (No such file or directory)
0.022 connect(3, 0x58266af0, 110) = -1 ENOENT (No such file or directory)
0.150 connect(4, 0x58266b00, 110) = 0
0.490 connect(7, 0x58264150, 110) = -1 ENOENT (No such file or directory)
0.505 connect(7, 0x58264300, 110) = -1 ENOENT (No such file or directory)
0.832 connect(5, 0x58266220, 110) = -1 ENOENT (No such file or directory)
0.847 connect(5, 0x582663e0, 110) = -1 ENOENT (No such file or directory)
0.899 connect(5, 0x95ba0630, 16) = 0
25.619 connect(6, 0x58266360, 110) = 0
40.564 connect(6, 0x58266330, 110) = 0
root@localhost's password: ^C
#
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-624f6jxic04031tnt40va4dd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When we add events via the '[trace]' section in perfconfig the command
line options are not yet processed, so when something goes wrong with
parsing those events and using --verbose is advised, we end up not
getting any more verbosity by doing so.
So just copy the trace.add_events string for later processing, after we
processed --verbose and the other command line options.
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-d6wbnz85ftqljdll6ynjyjd8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As this has all the things needed to format tracepoints events, not just
syscalls, that, after all, are just tracepoints with a set in stone ABI,
i.e. order and number of parameters.
For tracepoints we'll create a
static struct syscall_fmt tracepoint_fmts[]
array and will fill the ->arg[] entries with the beautifier for each
positional argument and record the name, then, when we need it, we'll
just check that the position has the same name, maybe even type, so that
we can do some check that the tracepoint hasn't changed, if it has, we
can even reorder things.
Keep calling it syscall_fmt but use it as well for tracepoints, do it
this way to minimize changes and reuse what is in place for syscalls,
we'll see.
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-2x1jgiev13zt4njaanlnne0d@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As this isn't used at all in mmap.h but in evlist.h, so to cut down the
header dependency tree, move it to where it is used.
Also add mmap.h to the places using it but previously getting it
indirectly via evlist.h.
Add missing pthread.h to evlist.h, as it has a pthread_t struct member
and was getting the header via mmap.h.
Noticed while processing a Jiri's libperf batch touching mmap.h, where
almost everything gets rebuilt because evlist.h is so popular, so cut
down't this rebuild the world party.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lkml.kernel.org/n/tip-he0uljeftl0xfveh3d6vtode@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf trace' reports the segmentation fault as below on Arm64:
# perf trace -e string -e augmented_raw_syscalls.c
LLVM: dumping tools/perf/examples/bpf/augmented_raw_syscalls.o
perf: Segmentation fault
Obtained 12 stack frames.
perf(sighandler_dump_stack+0x47) [0xaaaaac96ac87]
linux-vdso.so.1(+0x5b7) [0xffffadbeb5b7]
/lib/aarch64-linux-gnu/libc.so.6(strlen+0x10) [0xfffface7d5d0]
/lib/aarch64-linux-gnu/libc.so.6(_IO_vfprintf+0x1ac7) [0xfffface49f97]
/lib/aarch64-linux-gnu/libc.so.6(__vsnprintf_chk+0xc7) [0xffffacedfbe7]
perf(scnprintf+0x97) [0xaaaaac9ca3ff]
perf(+0x997bb) [0xaaaaac8e37bb]
perf(cmd_trace+0x28e7) [0xaaaaac8ec09f]
perf(+0xd4a13) [0xaaaaac91ea13]
perf(main+0x62f) [0xaaaaac8a147f]
/lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0xe3) [0xfffface22d23]
perf(+0x57723) [0xaaaaac8a1723]
Segmentation fault
This issue is introduced by commit 30a910d7d3 ("perf trace:
Preallocate the syscall table"), it allocates trace->syscalls.table[]
array and the element count is 'trace->sctbl->syscalls.nr_entries'; but
on Arm64, the system call number is not continuously used; e.g. the
syscall maximum id is 436 but the real entries is only 281.
So the table is allocated with 'nr_entries' as the element count, but it
accesses the table with the syscall id, which might be out of the bound
of the array and cause the segmentation fault.
This patch allocates trace->syscalls.table[] with the element count is
'trace->sctbl->syscalls.max_id + 1', this allows any id to access the
table without out of the bound.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Fixes: 30a910d7d3 ("perf trace: Preallocate the syscall table")
Link: http://lkml.kernel.org/r/20190809104752.27338-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move the perf_event_attr struct fron 'struct evsel' to 'struct perf_evsel'.
Committer notes:
Fixed up these:
tools/perf/arch/arm/util/auxtrace.c
tools/perf/arch/arm/util/cs-etm.c
tools/perf/arch/arm64/util/arm-spe.c
tools/perf/arch/s390/util/auxtrace.c
tools/perf/util/cs-etm.c
Also
cc1: warnings being treated as errors
tests/sample-parsing.c: In function 'do_test':
tests/sample-parsing.c:162: error: missing initializer
tests/sample-parsing.c:162: error: (near initialization for 'evsel.core.cpus')
struct evsel evsel = {
.needs_swap = false,
- .core.attr = {
- .sample_type = sample_type,
- .read_format = read_format,
+ .core = {
+ . attr = {
+ .sample_type = sample_type,
+ .read_format = read_format,
+ },
[perfbuilder@a70e4eeb5549 /]$ gcc --version |& head -1
gcc (GCC) 4.4.7
Also we don't need to include perf_event.h in
tools/perf/lib/include/perf/evsel.h, forward declaring 'struct
perf_event_attr' is enough. And this even fixes the build in some
systems where things are used somewhere down the include path from
perf_event.h without defining __always_inline.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190721112506.12306-43-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have an augmenter for the "open" syscall, which has just one pointer,
in the first argument, a "const char *", so any other syscall that has
just one pointer and that is the first can reuse the "open" BPF
augmenter program.
Even more, syscalls that get two pointers with the first being a string
can reuse "open"'s BPF augmenter till we have an augmenter that better
matches that syscall with two pointers.
With this the few augmenters we have, for open (first arg is a string),
openat (2nd arg is a string), renameat (2nd and 4th are strings) can be
reused by a lot of syscalls, ditto for "bind" reusing "connect" because
both have the 2nd argument as a sockaddr and the 3rd as its len.
Lets see how this makes the "bind" syscall reuse the "connect" BPF prog
augmenter found in tools/perf/examples/bpf/augmented_raw_syscalls.c:
# perf trace -e bind,connect systemctl restart sshd
connect(3, { .family: PF_LOCAL, path: /run/systemd/private }, 23) = 0
#
Oh, it just connects to some daemon, so we better do it system wide and then
stop/start sshd:
# perf trace -e bind,connect
systemctl/10124 connect(3, { .family: PF_LOCAL, path: /run/systemd/private }, 23) = 0
sshd/10102 connect(7, { .family: PF_LOCAL, path: /dev/log }, 110) = 0
systemctl/10126 connect(3, { .family: PF_LOCAL, path: /run/systemd/private }, 23) = 0
systemd/10128 ... [continued]: connect()) = 0
(sshd)/10128 connect(3, { .family: PF_LOCAL, path: /run/systemd/journal/stdout }, 30) ...
sshd/10128 bind(3, { .family: PF_NETLINK }, 12) = 0
sshd/10128 connect(4, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
sshd/10128 connect(3, { .family: PF_INET6, port: 22, addr: :: }, 28) = 0
sshd/10128 connect(3, { .family: PF_UNSPEC }, 16) = 0
sshd/10128 connect(3, { .family: PF_INET, port: 22, addr: 0.0.0.0 }, 16) = 0
sshd/10128 connect(3, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
sshd/10128 connect(3, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
sshd/10128 connect(5, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
sshd/10128 connect(5, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 110) = -1 ENOENT (No such file or directory)
sshd/10128 bind(4, { .family: PF_INET, port: 22, addr: 0.0.0.0 }, 16) = 0
sshd/10128 connect(6, { .family: PF_LOCAL, path: /dev/log }, 110) = 0
sshd/10128 bind(6, { .family: PF_INET6, port: 22, addr: :: }, 28) = 0
sshd/10128 connect(7, { .family: PF_LOCAL, path: /dev/log }, 110) = 0
^C#
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-zfley2ghs4nim1uq4nu6ed3l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
We iterate thru the syscall table produced from the kernel syscall
tables reading info, propagate the error and add to the debug message.
This helps in fixing further bugs, such as failing to read the
"sendfile" syscall info when it really should try the aliasm
"sendfile64".
Problems reading syscall 40: 2 (No such file or directory)(sendfile) information
# grep sendfile /tmp/build/perf/arch/x86/include/generated/asm/syscalls_64.c
[40] = "sendfile",
#
I.e. in the tracefs format file for the syscall tracepoints we have it
as sendfile64:
# find /sys -type f -name format | grep sendfile
/sys/kernel/debug/tracing/events/syscalls/sys_enter_sendfile64/format
/sys/kernel/debug/tracing/events/syscalls/sys_exit_sendfile64/format
#
But as "sendfile" in the file used to build the syscall table used in
perf:
$ grep sendfile arch/x86/entry/syscalls/syscall_64.tbl
40 common sendfile __x64_sys_sendfile64
$
So we need to add, in followup patches, aliases in 'perf trace' syscall
data structures to cope with thie.
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-w3eluap63x9je0bb8o3t79tz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
