Replace the errno_to_name() from the audit-libs with the newly
introduced arch_syscalls__strerrno() function.

With this change:

1.  With replacing errno_to_name() from audit-libs, perf trace
    does no longer require audit-lib interfaces.

2. In addition to 1, the audit-libs dependency can be removed
   for architectures that support syscall tables in perf.
   This is achieved in a follow-up commit.

3. With the architecture specific errno number/name mapping,
   perf trace reports can work across architectures.
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: linux-s390@vger.kernel.org
LPU-Reference: 1516352177-11106-5-git-send-email-brueckner@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-xjvoqzhwmu4wn4kl9ng11rvs@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Introduce a script that generates a mapping of errno numbers to their
names for each architecture that is supported by perf (i.e.  has a
subdirectory in tools/perf/arch/).

The errno mapping is generated as part of the trace beautifiers and can
be used by including the trace/beauty/arch_errno_names.c file.  Then,
use arch_syscalls__strerrno() to look up an errno value to obtain the
errno name (e.g. ENOENT) for a particular architecture.
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: linux-s390@vger.kernel.org
LPU-Reference: 1516352177-11106-4-git-send-email-brueckner@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-8zlsjnuoep2ww39aq5z41fno@git.kernel.org
[ Make x86 be the first arch, most common, add newline to last line, fixing build on centos:5 ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is a pre-req to generate an architecture specific mapping of errno
numbers to their names.  This errno mapping can be used by perf trace to
support cross-architecture trace reports and to get rid of the
audit-libs dependency.
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: linux-s390@vger.kernel.org
LPU-Reference: 1516352177-11106-3-git-send-email-brueckner@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-q13ystrw4sjz4wyvd3654cnm@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

For each arch in tools/perf/arch, grab a copy of errno.h.

This is a pre-req to generate an architecture specific mapping of errno
numbers to their names.  This errno mapping can be used by perf trace to
support cross-architecture trace reports and to get rid of the
audit-libs dependency.
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: linux-s390@vger.kernel.org
LPU-Reference: 1516352177-11106-2-git-send-email-brueckner@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-73azjhrzpjsskwi129020i2u@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Display the state of the rest of the features (FEATURE_TESTS_EXTRA) on a
'make VF=1' build. These features are detected manually by perf's
Makefile.config so they can't be displayed with the main list, but only
after we're done in Makefile.config.

  $ make VF=1
    BUILD:   Doing 'make -j4' parallel build

  Auto-detecting system features:
  ...                         dwarf: [ on  ]
  ...            dwarf_getlocations: [ on  ]
  ...                         glibc: [ on  ]
  ...                          gtk2: [ on  ]

SNIP

  ...                       timerfd: [ on  ]
  ...                  sched_getcpu: [ on  ]
  ...                           sdt: [ on  ]
  ...                         setns: [ on  ]

extra features:
  ...                        bionic: [ OFF ]
  ...                    compile-32: [ on  ]
  ...                   compile-x32: [ OFF ]
  ...                cplus-demangle: [ on  ]
  ...                         hello: [ OFF ]
  ...                 libbabeltrace: [ on  ]
  ...                       liberty: [ on  ]
  ...                     liberty-z: [ on  ]
  ...         libunwind-debug-frame: [ OFF ]
  ...     libunwind-debug-frame-arm: [ OFF ]
  ... libunwind-debug-frame-aarch64: [ OFF ]

SNIP
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180109092646.GB11520@kravaSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Commit (93d10af2 perf tools: Optimize sample parsing for ordered
events) breaks intelPT trace decoding by invariably returning an error
if the event type isn't a PERF_SAMPLE_TIME.

With this patch the timestamp is initialised and processing is allowed
to continue if the error returned by function
perf_evlist__parse_sample_timestamp() is not a fault.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 93d10af2 ("perf tools: Optimize sample parsing for ordered events")
Link: http://lkml.kernel.org/r/1515616312-27645-1-git-send-email-mathieu.poirier@linaro.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

I've meet a strange behavior with these commands on my gentoo box:

1: perf kmem record
2: CTRL-C to stop 1
3: perf report
4: "Enter", "Enter", "Run scripts for all samples",
   "event_analyzing_sample".

Then 'perf report' says:

  "
  No kallsyms or vmlinux with build-id xxxx was found
  /lib/modules/4.10.0+/build/vmlinux with build id xxxx not found,
  continuing without symbols
  ".

It is strange because I am sure /lib/modules/4.10.0+/build/vmlinux is
right for perf.data.

After digging, I found out the reason is that "perf report" generates
many open fds, then "script_browse" uses popen to run "perf script"
which run out of open files.

The gentoo box has a small default value for "max open files", 1024.
Yes, "ulimit -n " with a bigger number could fix it, but I think that
using O_CLOEXEC in do_open is a better way.
Signed-off-by: NWang YanQing <udknight@gmail.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180115050448.GA20759@udknight
[ Make sure O_CLOEXEC is available in old systems by adding a patch
  just before this one, to keep this bisectable in such systems ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To be more generally available and get the build on centos:5 to
work after we use O_CLOEXEC in the next patch, in the util/dso.c file.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.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>
Cc: Wang YanQing <udknight@gmail.com>
Link: https://lkml.kernel.org/n/tip-vsjbiydh15pfqomxw1kx64ex@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When clang is not linked with 'perf' we should just add a debug message
about that before doing the fallback to calling the external compiler.

I.e. just the "-95" warning below gets turned into a debug message:

  # cat sys_enter_open.c
  #include "bpf.h"

  SEC("syscalls:sys_enter_open")
  int func(void *ctx)
  {
	struct {
		char *ptr;
		char path[256];
	} filename = {
		.ptr = *((char **)(ctx + 16)),
	};
	int len = bpf_probe_read_str(filename.path, sizeof(filename.path), filename.ptr);
	if (len > 0) {
		if (len == 1)
			perf_event_output(ctx, &__bpf_stdout__, BPF_F_CURRENT_CPU, &filename, len + sizeof(filename.ptr));
		else if (len < 256)
			perf_event_output(ctx, &__bpf_stdout__, BPF_F_CURRENT_CPU, &filename, len + sizeof(filename.ptr));
        }
	return 0;
  }
  # trace -e open,sys_enter_open.c
  bpf: builtin compilation failed: -95, try external compiler
     0.000 (         ): __bpf_stdout__:@......./proc/self/task/11160/comm..)
     0.014 ( 0.116 ms): qemu-system-x8/6721 open(filename: /proc/self/task/11160/comm, flags: RDWR) = 91
  2335.411 (         ): __bpf_stdout__:FB..~.../etc/resolv.conf....)
  2335.421 ( 0.030 ms): chronyd/883 open(filename: /etc/resolv.conf, flags: CLOEXEC) = 5
^C#

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-z5aak9oay448ffj37giz94yr@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

So that we can get it working for TUI, where using just pr_err() would
end up making the message emitted to stderr to be erased by the TUI exit
routine restoring the terminal to its previous state.

Now we can see that trying to use a tracepoint field as one of the
--field entries isn't working:

  # perf top --stdio --no-children -e syscalls:sys_enter_write --fields pid,sym,count
  Error:
  Unknown --fields key: `count'
   Usage: perf top [<options>]

        --fields <key[,keys...]>
                          output field(s): overhead, period, sample plus all of sort keys
  #

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-usy9hhy7umdd4bbblkn63t8w@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There is never a need to synthesize a 'swapped' sample, so all callers
to perf_event__synthesize_sample() pass 'false' as the value to
'swapped'. So get rid of the unused 'swapped' parameter.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1516108492-21401-4-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

PERF_SAMPLE_CPU contains the cpu number in the first 4 bytes and the
second 4 bytes are reserved. Ensure the reserved bytes are zero in
perf_event__synthesize_sample().
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1516108492-21401-3-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Both 'perf inject' and internal tools consume cpu endian samples, so
there is never a need to do any swapping when synthesizing samples.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1516108492-21401-2-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In x86 architecture dependend part function get_cpuid_str() mallocs a
128 byte buffer, but does not check if the memory allocation succeeded
or not.

When the memory allocation fails, function __get_cpuid() is called with
first parameter being a NULL pointer.  However this function references
its first parameter and operates on a NULL pointer which might cause
core dumps.
Signed-off-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180117131611.34319-1-tmricht@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Previously it was only allowed to use at most 10 time slices in 'perf
script --time'.

This patch removes this limitation.
For example, following command line is OK (12 time slices)

perf script --time 1%/1,1%/2,1%/3,1%/4,1%/5,1%/6,1%/7,1%/8,1%/9,1%/10,1%/11,1%/12
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-9-git-send-email-yao.jin@linux.intel.com
[ No need to check for NULL to call free, use zfree ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Previously it was only allowed to use at most 10 time slices in 'perf
report --time'.

This patch removes this limitation.
For example, following command line is OK (12 time slices)

perf report --stdio --time 1%/1,1%/2,1%/3,1%/4,1%/5,1%/6,1%/7,1%/8,1%/9,1%/10,1%/11,1%/12
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-8-git-send-email-yao.jin@linux.intel.com
[ No need to check for NULL to call free, use zfree ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Previously we use a magic number 10 to limit the number of time slices.
It's not very good.

This patch creates a new function perf_time__range_alloc() to allocate
time slices buffer. The number of buffer entries is determined by the
number of comma in string but at least it will allocate one entry even
if no comma is found.
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-7-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add a time slices indication to the perf report header.

For example,

  # perf report --stdio --time 10%

  # Total Lost Samples: 0
  #
  # Samples: 9K of event 'cycles:ppp' (time slices: 10%)
  # Event count (approx.): 8951288803
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Suggested--by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-6-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Previously, the time percent slice needs an index to specify which one
the user wants.

It may be easier to use if the index can be omitted.  So with this
patch, for example,

perf report --stdio --time 10%/1 should be equivalent to
perf report --stdio --time 10%
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-5-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The command line like 'perf report --stdio --time 1abc%/1' could be
accepted by perf. It looks not very good.

This patch uses strtod() to replace original atof() and check the entire
string. Now for the same command line, it would return error message
"Invalid time string".

root@skl:/tmp# perf report --stdio --time 1abc%/1
Invalid time string
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-4-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The following message will be returned to user when executing 'perf
script --time' if perf data file doesn't contain the first/last sample
time.

"HINT: no first/last sample time found in perf data.
 Please use latest perf binary to execute 'perf record'
 (if '--buildid-all' is enabled, needs to set '--timestamp-boundary')."
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-3-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The following message will be returned to user when executing
'perf report --time' if perf data file doesn't contain the
first/last sample time.

"HINT: no first/last sample time found in perf data.
 Please use latest perf binary to execute 'perf record'
 (if '--buildid-all' is enabled, needs to set '--timestamp-boundary')."
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1515596433-24653-2-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When we use a global DWARF setting as in:

	perf record --call-graph dwarf

According to 5c0cf224 ("perf record: Store data mmaps for dwarf unwind") we need
to set up some extra perf_event_attr bits.

But when we instead do a per event dwarf setting:

	perf record -e cycles/call-graph=dwarf/

This was not being done, make them equivalent.

This didn't produce any output changes in my tests while fixing up loose
ends in the per-event settings, I found it just by comparing the
perf_event_attr fields trying to find an explanation for those problems.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Noel Grandin <noelgrandin@gmail.com>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-6476r53h2o38skbs9qa4ust4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The per-event max-stack setting wasn't overriding the global --max-stack
setting:

  # perf trace --no-syscalls --max-stack 4 -e probe_libc:inet_pton/call-graph=dwarf,max-stack=2/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.072 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.072/0.072/0.072/0.000 ms
       0.000 probe_libc:inet_pton:(7feb7a998350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffaa39b6108f3f] (/usr/bin/ping)
  #

Fix it:

  # perf trace --no-syscalls --max-stack 4 -e probe_libc:inet_pton/call-graph=dwarf,max-stack=2/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.073 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.073/0.073/0.073/0.000 ms
       0.000 probe_libc:inet_pton:(7f1083221350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ic3g837xg8ob3kcpkspxwz0g@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If we use:

	perf trace --max-stack=4

then the syscall events will use DWARF callchains, when available
(libunwind enabled in the build) and the printing will stop at 4 levels.

When we introduced support for tracepoint events this ended up not
applying for them, fix it.

Before:

  # perf trace --call-graph=dwarf --no-syscalls -e probe_libc:inet_pton ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.058 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.058/0.058/0.058/0.000 ms
       0.000 probe_libc:inet_pton:(7fc6c2a16350))
  #

After:

  # perf trace --call-graph=dwarf --no-syscalls -e probe_libc:inet_pton ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.087 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.087/0.087/0.087/0.000 ms
       0.000 probe_libc:inet_pton:(7fbf9a041350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffaa947cb67f3f] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffaa947cb68379] (/usr/bin/ping)
  #
Reported-by: NThomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.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-afsu9eegd43ppihiuafhh9qv@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When setting up DWARF callchains on specific events, without using
'record' or 'trace' --call-graph, but instead doing it like:

	perf trace -e cycles/call-graph=dwarf/

The unwind__prepare_access() call in thread__insert_map() when we
process PERF_RECORD_MMAP(2) metadata events were not being performed,
precluding us from using per-event DWARF callchains, handling them just
when we asked for all events to be DWARF, using "--call-graph dwarf".

We do it in the PERF_RECORD_MMAP because we have to look at one of the
executable maps to figure out the executable type (64-bit, 32-bit) of
the DSO laid out in that mmap. Also to look at the architecture where
the perf.data file was recorded.

All this probably should be deferred to when we process a sample for
some thread that has callchains, so that we do this processing only for
the threads with samples, not for all of them.

For now, fix using DWARF on specific events.

Before:

  # perf trace --no-syscalls -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.048 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.048/0.048/0.048/0.000 ms
     0.000 probe_libc:inet_pton:(7fe9597bb350))
  Problem processing probe_libc:inet_pton callchain, skipping...
  #

After:

  # perf trace --no-syscalls -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.060 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.060/0.060/0.060/0.000 ms
       0.000 probe_libc:inet_pton:(7fd4aa930350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffaa804e51af3f] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffaa804e51b379] (/usr/bin/ping)
  #
  # perf trace --call-graph=dwarf --no-syscalls -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.057 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.057/0.057/0.057/0.000 ms
       0.000 probe_libc:inet_pton:(7f9363b9e350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffa9e8a14e0f3f] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffa9e8a14e1379] (/usr/bin/ping)
  #
  # perf trace --call-graph=fp --no-syscalls -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.077 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.077/0.077/0.077/0.000 ms
       0.000 probe_libc:inet_pton:(7f4947e1c350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffaa716d88ef3f] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffaa716d88f379] (/usr/bin/ping)
  #
  # perf trace --no-syscalls -e probe_libc:inet_pton/call-graph=fp/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.078 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.078/0.078/0.078/0.000 ms
       0.000 probe_libc:inet_pton:(7fa157696350))
                                         __GI___inet_pton (/usr/lib64/libc-2.26.so)
                                         getaddrinfo (/usr/lib64/libc-2.26.so)
                                         [0xffffa9ba39c74f40] (/usr/bin/ping)
  #
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/r/20180116182650.GE16107@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When setting the "dwarf" unwinder for a specific event and not
specifying the max-stack, the attr.sample_max_stack ended up using an
uninitialized callchain_param.max_stack, fix it by using designated
initializers for that callchain_param variable, zeroing all non
explicitely initialized struct members.

Here is what happened:

  # perf trace -vv --no-syscalls --max-stack 4 -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  callchain: type DWARF
  callchain: stack dump size 8192
  perf_event_attr:
    type                             2
    size                             112
    config                           0x730
    { sample_period, sample_freq }   1
    sample_type                      IP|TID|TIME|ADDR|CALLCHAIN|CPU|PERIOD|RAW|REGS_USER|STACK_USER|DATA_SRC
    exclude_callchain_user           1
    { wakeup_events, wakeup_watermark } 1
    sample_regs_user                 0xff0fff
    sample_stack_user                8192
    sample_max_stack                 50656
  sys_perf_event_open failed, error -75
  Value too large for defined data type
  # perf trace -vv --no-syscalls --max-stack 4 -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  callchain: type DWARF
  callchain: stack dump size 8192
  perf_event_attr:
    type                             2
    size                             112
    config                           0x730
    sample_type                      IP|TID|TIME|ADDR|CALLCHAIN|CPU|PERIOD|RAW|REGS_USER|STACK_USER|DATA_SRC
    exclude_callchain_user           1
    sample_regs_user                 0xff0fff
    sample_stack_user                8192
    sample_max_stack                 30448
  sys_perf_event_open failed, error -75
  Value too large for defined data type
  #

Now the attr.sample_max_stack is set to zero and the above works as
expected:

  # perf trace --no-syscalls --max-stack 4 -e probe_libc:inet_pton/call-graph=dwarf/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.072 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.072/0.072/0.072/0.000 ms
       0.000 probe_libc:inet_pton:(7feb7a998350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffaa39b6108f3f] (/usr/bin/ping)
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-is9tramondqa9jlxxsgcm9iz@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

'perf record' and 'perf report --dump-raw-trace' supported in this
release.

Example usage:

 # perf record -e arm_spe/ts_enable=1,pa_enable=1/ dd if=/dev/zero of=/dev/null count=10000
 # perf report --dump-raw-trace

Note that the perf.data file is portable, so the report can be run on
another architecture host if necessary.

Output will contain raw SPE data and its textual representation, such
as:

0x5c8 [0x30]: PERF_RECORD_AUXTRACE size: 0x200000  offset: 0  ref: 0x1891ad0e  idx: 1  tid: 2227  cpu: 1
.
. ... ARM SPE data: size 2097152 bytes
.  00000000:  49 00                                           LD
.  00000002:  b2 c0 3b 29 0f 00 00 ff ff                      VA 0xffff00000f293bc0
.  0000000b:  b3 c0 eb 24 fb 00 00 00 80                      PA 0xfb24ebc0 ns=1
.  00000014:  9a 00 00                                        LAT 0 XLAT
.  00000017:  42 16                                           EV RETIRED L1D-ACCESS TLB-ACCESS
.  00000019:  b0 00 c4 15 08 00 00 ff ff                      PC 0xff00000815c400 el3 ns=1
.  00000022:  98 00 00                                        LAT 0 TOT
.  00000025:  71 36 6c 21 2c 09 00 00 00                      TS 39395093558
.  0000002e:  49 00                                           LD
.  00000030:  b2 80 3c 29 0f 00 00 ff ff                      VA 0xffff00000f293c80
.  00000039:  b3 80 ec 24 fb 00 00 00 80                      PA 0xfb24ec80 ns=1
.  00000042:  9a 00 00                                        LAT 0 XLAT
.  00000045:  42 16                                           EV RETIRED L1D-ACCESS TLB-ACCESS
.  00000047:  b0 f4 11 16 08 00 00 ff ff                      PC 0xff0000081611f4 el3 ns=1
.  00000050:  98 00 00                                        LAT 0 TOT
.  00000053:  71 36 6c 21 2c 09 00 00 00                      TS 39395093558
.  0000005c:  48 00                                           INSN-OTHER
.  0000005e:  42 02                                           EV RETIRED
.  00000060:  b0 2c ef 7f 08 00 00 ff ff                      PC 0xff0000087fef2c el3 ns=1
.  00000069:  98 00 00                                        LAT 0 TOT
.  0000006c:  71 d1 6f 21 2c 09 00 00 00                      TS 39395094481
...

Other release notes:

- applies to acme's perf/{core,urgent} branches, likely elsewhere

- Report is self-contained within the tool.
  Record requires enabling the kernel SPE driver by
  setting CONFIG_ARM_SPE_PMU.

- The intel-bts implementation was used as a starting point; its
  min/default/max buffer sizes and power of 2 pages granularity need to be
  revisited for ARM SPE

- Recording across multiple SPE clusters/domains not supported

- Snapshot support (record -S), and conversion to native perf events
  (e.g., via 'perf inject --itrace'), are also not supported

- Technically both cs-etm and spe can be used simultaneously, however
  disabled for simplicity in this release
Signed-off-by: NKim Phillips <kim.phillips@arm.com>
Reviewed-by: NDongjiu Geng <gengdongjiu@huawei.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180114132850.0b127434b704a26bad13268f@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If a field is a dynamic string, get_field_str() returned just the
offset/size value and not the string. Have it parse the offset/size
correctly to return the actual string. Otherwise filtering fails when
trying to filter fields that are dynamic strings.
Reported-by: NGopanapalli Pradeep <prap_hai@yahoo.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20180112004823.146333275@goodmis.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently the FILTER_TRIVIAL_FALSE case has a missing break statement,
if the trivial type is FALSE, it will also run into the TRUE case, and
always be skipped as the TRUE statement will continue the loop on the
inverse condition of the FALSE statement.
Reported-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20180112004823.012918807@goodmis.org
Link: http://lkml.kernel.org/r/1493218540-12296-1-git-send-email-treeze.taeung@gmail.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add UL suffix to MISSING_EVENTS since ints shouldn't be left shifted by 31.
Signed-off-by: NMichael Sartain <mikesart@fastmail.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20171016165542.13038-4-mikesart@fastmail.com
Link: http://lkml.kernel.org/r/20180112004822.829533885@goodmis.orgSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It makes the code clearer and less error prone.

clearer:
- less code
- the code is now using the same format to create strings dynamically

less error prone:
- no magic number +2 +9 +5 to compute the size
- no copy&paste of the strings to compute the size and to concatenate

The function `asprintf` is not POSIX standard but the program
was already using it. Later it can be decided to use only POSIX
functions, then we can easly replace all the `asprintf(3)` with a local
implementation of that function.
Signed-off-by: NFederico Vaga <federico.vaga@vaga.pv.it>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Federico Vaga <federico.vaga@vaga.pv.it>
Link: http://lkml.kernel.org/r/20170802221558.9684-2-federico.vaga@vaga.pv.it
Link: http://lkml.kernel.org/r/20180112004822.686281649@goodmis.orgSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When a record has an unrecognized type, an error message is reported,
but it would also be helpful to see the contents of that record. At
least show what it is in hex, instead of just showing a blank line.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20180112004822.542204577@goodmis.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The Linux kernel printf() has some extended use cases that dereference
the pointer. This is dangerouse for tracing because the pointer that is
dereferenced can change or even be unmapped. It also causes issues when
the trace data is extracted, because user space does not have access to
the contents of the pointer even if it still exists.

To handle this, the kernel was updated to process these dereferenced
pointers at the time they are recorded, and not post processed. Now they
exist in the tracing buffer, and no dereference is needed at the time of
reading the trace.

The event parsing library needs to handle this new case.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20180112004822.403349289@goodmis.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When processing %pX in pretty_print(), simplify the logic slightly by
incrementing the ptr to the format string if isalnum(ptr[1]) is true.
This follows the logic a bit more closely to what is in the kernel.

Also, this fixes a small bug where %pF was not giving the offset of the
function.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20180112004822.260262257@goodmis.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Aligns trace-cmd with the behavior of the kernel.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/e60c889f-55e7-4ee8-0e50-151e435ffd8c@siemens.com
Link: http://lkml.kernel.org/r/20180112004822.118332436@goodmis.orgSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If the value contains bits that are not defined by print_flags() helper,
then show the remaining bits. This aligns with the functionality of the
kernel.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/e60c889f-55e7-4ee8-0e50-151e435ffd8c@siemens.com
Link: http://lkml.kernel.org/r/20180112004821.976225232@goodmis.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Older kernels have a bug that creates invalid symbols. event-parse.c
handles them by replacing them with a "%s" token. But the fix included
an extra backslash, and "\%s" was added incorrectly.
Signed-off-by: NMichael Sartain <mikesart@fastmail.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20180112004821.827168881@goodmis.org
Link: http://lkml.kernel.org/r/d320000d37c10ce0912851e1fb78d1e0c946bcd9.1497486273.git.mikesart@fastmail.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The raw_syscalls:sys_{enter,exit} were first supported in 'perf trace',
together with minor and major page faults, then we supported
--call-graph, then --max-stack, but when the other tracepoints got
supported, and bpf, etc, I forgot to make those global call-graph
settings apply to them.

Fix it by realizing that the global --max-stack and --call-graph
settings are done via:

        OPT_CALLBACK(0, "call-graph", &trace.opts,
                     "record_mode[,record_size]", record_callchain_help,
                     &record_parse_callchain_opt),

And then, when we go to parse the events in -e via:

        OPT_CALLBACK('e', "event", &trace, "event",
                     "event/syscall selector. use 'perf list' to list available events",
                     trace__parse_events_option),

And trace__parse_sevents_option() calls:

                struct option o = OPT_CALLBACK('e', "event", &trace->evlist, "event",
                                               "event selector. use 'perf list' to list available events",
                                               parse_events_option);
                err = parse_events_option(&o, lists[0], 0);

parse_events_option() will override the global --call-graph and
--max-stack if the "call-graph" and/or "max-stack" terms are in the
event definition, such as in the probe_libc:inet_pton event in one of the
examples below (-e probe_libc:inet_pton/max-stack=2).

Before:

  # perf trace --mmap 1024 --call-graph dwarf -e sendto,probe_libc:inet_pton ping -6 -c 1 ::1
       1.525 (         ): probe_libc:inet_pton:(7f77f3ac9350))
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.071 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.071/0.071/0.071/0.000 ms
       1.677 ( 0.081 ms): ping/31296 sendto(fd: 3, buff: 0x55681b652720, len: 64, addr: 0x55681b650640, addr_len: 28) = 64
                                         __libc_sendto (/usr/lib64/libc-2.26.so)
                                         [0xffffaa97e4bc9cef] (/usr/bin/ping)
                                         [0xffffaa97e4bc656d] (/usr/bin/ping)
                                         [0xffffaa97e4bc7d0a] (/usr/bin/ping)
                                         [0xffffaa97e4bca447] (/usr/bin/ping)
                                         [0xffffaa97e4bc2f91] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffaa97e4bc3379] (/usr/bin/ping)
  #

After:

  # perf trace --mmap 1024 --call-graph dwarf -e sendto,probe_libc:inet_pton ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.089 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.089/0.089/0.089/0.000 ms
       1.955 (         ): probe_libc:inet_pton:(7f383a311350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
                                         [0xffffaa5d91444f3f] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffaa5d91445379] (/usr/bin/ping)
       2.140 ( 0.101 ms): ping/32047 sendto(fd: 3, buff: 0x55a26edd0720, len: 64, addr: 0x55a26edce640, addr_len: 28) = 64
                                         __libc_sendto (/usr/lib64/libc-2.26.so)
                                         [0xffffaa5d9144bcef] (/usr/bin/ping)
                                         [0xffffaa5d9144856d] (/usr/bin/ping)
                                         [0xffffaa5d91449d0a] (/usr/bin/ping)
                                         [0xffffaa5d9144c447] (/usr/bin/ping)
                                         [0xffffaa5d91444f91] (/usr/bin/ping)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         [0xffffaa5d91445379] (/usr/bin/ping)
  #

Same thing for --max-stack, the global one:

  # perf trace --max-stack 3 -e sendto,probe_libc:inet_pton ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.097 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.097/0.097/0.097/0.000 ms
       1.577 (         ): probe_libc:inet_pton:(7f32f3957350))
                                         __inet_pton (inlined)
                                         gaih_inet.constprop.7 (/usr/lib64/libc-2.26.so)
                                         __GI_getaddrinfo (inlined)
       1.738 ( 0.108 ms): ping/32103 sendto(fd: 3, buff: 0x55c3132d7720, len: 64, addr: 0x55c3132d5640, addr_len: 28) = 64
                                         __libc_sendto (/usr/lib64/libc-2.26.so)
                                         [0xffffaa3cecf44cef] (/usr/bin/ping)
                                         [0xffffaa3cecf4156d] (/usr/bin/ping)
  #

And then setting up a global setting (dwarf, max-stack=4), that will
affect the raw_syscall:sys_enter for the 'sendto' syscall and that will
be overriden in the probe_libc:inet_pton call to just one entry.

  # perf trace --max-stack=4 --call-graph dwarf -e sendto -e probe_libc:inet_pton/max-stack=1/ ping -6 -c 1 ::1
  PING ::1(::1) 56 data bytes
  64 bytes from ::1: icmp_seq=1 ttl=64 time=0.090 ms

  --- ::1 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 0.090/0.090/0.090/0.000 ms
       2.140 (         ): probe_libc:inet_pton:(7f9fe9337350))
                                         __GI___inet_pton (/usr/lib64/libc-2.26.so)
       2.283 ( 0.103 ms): ping/31804 sendto(fd: 3, buff: 0x55c7f3e19720, len: 64, addr: 0x55c7f3e17640, addr_len: 28) = 64
                                         __libc_sendto (/usr/lib64/libc-2.26.so)
                                         [0xffffaa380c402cef] (/usr/bin/ping)
                                         [0xffffaa380c3ff56d] (/usr/bin/ping)
                                         [0xffffaa380c400d0a] (/usr/bin/ping)
  #

Install iputils-debuginfo to get those /usr/bin/ping addresses resolved,
those routines are not on its .dymsym nor .symtab :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-qgl2gse8elhh9zztw4ajopg3@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The construct:

	if (callchain_param)
		perf_evsel__config_callchain(evsel, opts, &callchain_param);

happens in several places, so make perf_evsel__config_callchain() work
just like free(NULL), do nothing if param->enabled is not set.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ykk0qzxnxwx3o611ctjnmxav@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>