[ Upstream commit 8a07aa4e9b7b0222129c07afff81634a884b2866 ]
Debugging a OOM error using the TUI interface revealed this issue
on s390:
[tmricht@m83lp54 perf]$ cat /proc/kallsyms |sort
....
00000001119b7158 B radix_tree_node_cachep
00000001119b8000 B __bss_stop
00000001119b8000 B _end
000003ff80002850 t autofs_mount [autofs4]
000003ff80002868 t autofs_show_options [autofs4]
000003ff80002a98 t autofs_evict_inode [autofs4]
....
There is a huge gap between the last kernel symbol
__bss_stop/_end and the first kernel module symbol
autofs_mount (from autofs4 module).
After reading the kernel symbol table via functions:
dso__load()
+--> dso__load_kernel_sym()
+--> dso__load_kallsyms()
+--> __dso_load_kallsyms()
+--> symbols__fixup_end()
the symbol __bss_stop has a start address of 1119b8000 and
an end address of 3ff80002850, as can be seen by this debug statement:
symbols__fixup_end __bss_stop start:0x1119b8000 end:0x3ff80002850
The size of symbol __bss_stop is 0x3fe6e64a850 bytes!
It is the last kernel symbol and fills up the space until
the first kernel module symbol.
This size kills the TUI interface when executing the following
code:
process_sample_event()
hist_entry_iter__add()
hist_iter__report_callback()
hist_entry__inc_addr_samples()
symbol__inc_addr_samples(symbol = __bss_stop)
symbol__cycles_hist()
annotated_source__alloc_histograms(...,
symbol__size(sym),
...)
This function allocates memory to save sample histograms.
The symbol_size() marco is defined as sym->end - sym->start, which
results in above value of 0x3fe6e64a850 bytes and
the call to calloc() in annotated_source__alloc_histograms() fails.
The histgram memory allocation might fail, make this failure
no-fatal and continue processing.
Output before:
[tmricht@m83lp54 perf]$ ./perf --debug stderr=1 report -vvvvv \
-i ~/slow.data 2>/tmp/2
[tmricht@m83lp54 perf]$ tail -5 /tmp/2
__symbol__inc_addr_samples(875): ENOMEM! sym->name=__bss_stop,
start=0x1119b8000, addr=0x2aa0005eb08, end=0x3ff80002850,
func: 0
problem adding hist entry, skipping event
0x938b8 [0x8]: failed to process type: 68 [Cannot allocate memory]
[tmricht@m83lp54 perf]$
Output after:
[tmricht@m83lp54 perf]$ ./perf --debug stderr=1 report -vvvvv \
-i ~/slow.data 2>/tmp/2
[tmricht@m83lp54 perf]$ tail -5 /tmp/2
symbol__inc_addr_samples map:0x1597830 start:0x110730000 end:0x3ff80002850
symbol__hists notes->src:0x2aa2a70 nr_hists:1
symbol__inc_addr_samples sym:unlink_anon_vmas src:0x2aa2a70
__symbol__inc_addr_samples: addr=0x11094c69e
0x11094c670 unlink_anon_vmas: period++ [addr: 0x11094c69e, 0x2e, evidx=0]
=> nr_samples: 1, period: 526008
[tmricht@m83lp54 perf]$
There is no error about failed memory allocation and the TUI interface
shows all entries.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/90cb5607-3e12-5167-682d-978eba7dafa8@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Starting with binutils 2.28, aarch64 objdump adds comments to the
disassembly output to show the alternative names of a condition code
[1].
It is assumed that commas in objdump comments could occur in other
arches now or in the future, so this fix is arch-independent.
The fix could have been done with arm64 specific jump__parse and
jump__scnprintf functions, but the jump__scnprintf instruction would
have to have its comment character be a literal, since the scnprintf
functions cannot receive a struct arch easily.
This inconvenience also applies to the generic jump__scnprintf, which is
why we add a raw_comment pointer to struct ins_operands, so the __parse
function assigns it to be re-used by its corresponding __scnprintf
function.
Example differences in 'perf annotate --stdio2' output on an aarch64
perf.data file:
BEFORE: → b.cs ffff200008133d1c <unwind_frame+0x18c> // b.hs, dffff7ecc47b
AFTER : ↓ b.cs 18c
BEFORE: → b.cc ffff200008d8d9cc <get_alloc_profile+0x31c> // b.lo, b.ul, dffff727295b
AFTER : ↓ b.cc 31c
The branch target labels 18c and 31c also now appear in the output:
BEFORE: add x26, x29, #0x80
AFTER : 18c: add x26, x29, #0x80
BEFORE: add x21, x21, #0x8
AFTER : 31c: add x21, x21, #0x8
The Fixes: tag below is added so stable branches will get the update; it
doesn't necessarily mean that commit was broken at the time, rather it
didn't withstand the aarch64 objdump update.
Tested no difference in output for sample x86_64, power arch perf.data files.
[1] https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commit;h=bb7eff5206e4795ac79c177a80fe9f4630aaf730
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Fixes: b13bbeee5e ("perf annotate: Fix branch instruction with multiple operands")
Link: http://lkml.kernel.org/r/20180827125340.a2f7e291901d17cea05daba4@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add --percent-type option to set annotation percent type from following
choices:
global-period, local-period, global-hits, local-hits
Examples:
$ perf annotate --percent-type period-local --stdio | head -1
Percent | Source code ... es, percent: local period)
$ perf annotate --percent-type hits-local --stdio | head -1
Percent | Source code ... es, percent: local hits)
$ perf annotate --percent-type hits-global --stdio | head -1
Percent | Source code ... es, percent: global hits)
$ perf annotate --percent-type period-global --stdio | head -1
Percent | Source code ... es, percent: global period)
The local/global keywords set if the percentage is computed in the scope
of the function (local) or the whole data (global).
The period/hits keywords set the base the percentage is computed on -
the samples period or the number of samples (hits).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-20-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In following patches we will allow to switch percent type even for stdio
annotation outputs. Adding the percent type value into the annotation
outputs title.
$ perf annotate --stdio
Percent | Sou ... instructions:u } (2805 samples, percent: local period)
--------------------------- ... ------------------------------------------------------
...
$ perf annotate --stdio2
Samples: 2K of events 'anon ... count (approx.): 156525487, [percent: local period]
safe_write.c() /usr/bin/yes
Percent
...
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-19-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have more current function tto get the title for annotation,
which is hists__scnprintf_title. They both have same output as
far as the annotation's header line goes.
They differ in counting of the nr_samples, hists__scnprintf_title
provides more accurate number based on the setup of the
symbol_conf.filter_relative variable.
Plus it also displays any uid/thread/dso/socket filters/zooms
if there are set any, which annotation__scnprintf_samples_period
does not.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20180804130521.11408-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Making it a bit more robust, this took place here when a sample appeared
right after:
ffffffff8a925000 D __nosave_end
And before the next considered symbol, which, using kallsyms make us
over guess the size of __nosave_end, and then the sequence:
hist_entry__inc_addr_samples ->
symbol__inc_addr_samples ->
symbol__hists ->
annotated_source__alloc_histograms
Ends up not liking to allocate gigabytes of ram for annotation...
This will be alleviated by considering BSS symbols, which we should but
don't so far, and then we should investigate those samples further.
The testcase was to have:
perf top -e cycles/call-graph=fp/,cache-misses/call-graph=dwarf/,instructions
Running for a while till it segfaulted trying to access NULL notes->src->histograms.
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-ndfjtpiop3tdcnyjgp320ra8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When we perform the following command lines:
$ perf record -e "{cycles,branches}" ./div
$ perf annotate main --stdio
The output shows only the first event, "cycles" and the displaying
format is not correct.
Percent | Source code & Disassembly of div for cycles (44550 samples)
-----------------------------------------------------------------------------------
:
:
:
: Disassembly of section .text:
:
: 00000000004004b0 <main>:
: main():
:
: return i;
: }
:
: int main(void)
: {
0.00 : 4004b0: push %rbx
: int i;
: int flag;
: volatile double x = 1212121212, y = 121212;
:
: s_randseed = time(0);
0.00 : 4004b1: xor %edi,%edi
: srand(s_randseed);
0.00 : 4004b3: mov $0x77359400,%ebx
:
: return i;
: }
The issue is that the value of the 'nr_percent' variable is hardcoded to
1. This patch fixes it.
With this patch, the output is:
Percent | Source code & Disassembly of div for cycles (44550 samples)
-----------------------------------------------------------------------------------
:
:
:
: Disassembly of section .text:
:
: 00000000004004b0 <main>:
: main():
:
: return i;
: }
:
: int main(void)
: {
0.00 0.00 : 4004b0: push %rbx
: int i;
: int flag;
: volatile double x = 1212121212, y = 121212;
:
: s_randseed = time(0);
0.00 0.00 : 4004b1: xor %edi,%edi
: srand(s_randseed);
0.00 0.00 : 4004b3: mov $0x77359400,%ebx
:
: return i;
: }
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@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@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: f681d593d1 ("perf annotate: Remove disasm__calc_percent() from disasm_line__print()")
Link: http://lkml.kernel.org/r/1525881435-4092-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To match what is shown in the main 'perf report/top' title lines, i.e.
if a group is being shown, either a real group (recorded with "-e
'{a,b,c}') or a forced group (using 'perf report --group' for a
perf.data file recorded without {}) we will show multiple columns,
one per event, but we were failing to show the group details, so, for:
# perf report --header-only | grep cmdline
# cmdline : /home/acme/bin/perf record -e {cycles,instructions,cache-misses}
# perf report --group
The first line was showing just "cycles", now it shows the correct line,
which is:
Samples: 578 of events 'anon group { cycles, instructions, cache-misses }', 4000 Hz, Event count (approx.): 487421794
syscall_return_via_sysret /lib/modules/4.16.0-rc7/build/vmlinux
0.22 2.97 0.00 │ ↓ jmp 6c
│ mov %cr3,%rdi
1.33 10.89 4.00 │ ↓ jmp 62
│ mov %rdi,%rax
<SNIP>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 6920e2854e ("perf annotate browser: Show extra title line with event information")
Link: https://lkml.kernel.org/n/tip-i41tqh17c2dabnyzjh99r1oz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
