A recent fix for 'perf trace' introduced a bug where
machine__exit(trace->host) could be called while trace->host was still
NULL, so make this more robust by guarding against NULL, just like
free() does.
The problem happens, for instance, when !root users try to run 'perf
trace':
[acme@jouet linux]$ trace
Error: No permissions to read /sys/kernel/debug/tracing/events/raw_syscalls/sys_(enter|exit)
Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing'
perf: Segmentation fault
Obtained 7 stack frames.
[0x4f1b2e]
/lib64/libc.so.6(+0x3671f) [0x7f43a1dd971f]
[0x4f3fec]
[0x47468b]
[0x42a2db]
/lib64/libc.so.6(__libc_start_main+0xe9) [0x7f43a1dc3509]
[0x42a6c9]
Segmentation fault (core dumped)
[acme@jouet linux]$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 33974a414c ("perf trace: Call machine__exit() at exit")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On one hand this ensures that the memory is properly freed when the DSO
gets freed. On the other hand this significantly speeds up the
processing of the callchain nodes when lots of srclines are requested.
For one of my data files e.g.:
Before:
Performance counter stats for 'perf report -s srcline -g srcline --stdio':
52496.495043 task-clock (msec) # 0.999 CPUs utilized
634 context-switches # 0.012 K/sec
2 cpu-migrations # 0.000 K/sec
191,561 page-faults # 0.004 M/sec
165,074,498,235 cycles # 3.144 GHz
334,170,832,408 instructions # 2.02 insn per cycle
90,220,029,745 branches # 1718.591 M/sec
654,525,177 branch-misses # 0.73% of all branches
52.533273822 seconds time elapsedProcessed 236605 events and lost 40 chunks!
After:
Performance counter stats for 'perf report -s srcline -g srcline --stdio':
22606.323706 task-clock (msec) # 1.000 CPUs utilized
31 context-switches # 0.001 K/sec
0 cpu-migrations # 0.000 K/sec
185,471 page-faults # 0.008 M/sec
71,188,113,681 cycles # 3.149 GHz
133,204,943,083 instructions # 1.87 insn per cycle
34,886,384,979 branches # 1543.214 M/sec
278,214,495 branch-misses # 0.80% of all branches
22.609857253 seconds time elapsed
Note that the difference is only this large when `--inline` is not
passed. In such situations, we would use the inliner cache and thus do
not run this code path that often.
I think that this cache should actually be used in other places, too.
When looking at the valgrind leak report for perf report, we see tons of
srclines being leaked, most notably from calls to
hist_entry__get_srcline. The problem is that get_srcline has many
different formatting options (show_sym, show_addr, potentially even
unwind_inlines when calling __get_srcline directly). As such, the
srcline cannot easily be cached for all calls, or we'd have to add
caches for all formatting combinations (6 so far). An alternative would
be to remove the formatting options and handle that on a different level
- i.e. print the sym/addr on demand wherever we actually output
something. And the unwind_inlines could be moved into a separate
function that does not return the srcline.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Reviewed-by: 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: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171019113836.5548-4-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When no inlined frames could be found for a given address, we did not
store this information anywhere. That means we potentially do the costly
inliner lookup repeatedly for cases where we know it can never succeed.
This patch makes dso__parse_addr_inlines always return a valid
inline_node. It will be empty when no inliners are found. This enables
us to cache the empty list in the DSO, thereby improving the performance
when many addresses fail to find the inliners.
For my trivial example, the performance impact is already quite
significant:
Before:
~~~~~
Performance counter stats for 'perf report --stdio --inline -g srcline -s srcline' (5 runs):
594.804032 task-clock (msec) # 0.998 CPUs utilized ( +- 0.07% )
53 context-switches # 0.089 K/sec ( +- 4.09% )
0 cpu-migrations # 0.000 K/sec ( +-100.00% )
5,687 page-faults # 0.010 M/sec ( +- 0.02% )
2,300,918,213 cycles # 3.868 GHz ( +- 0.09% )
4,395,839,080 instructions # 1.91 insn per cycle ( +- 0.00% )
939,177,205 branches # 1578.969 M/sec ( +- 0.00% )
11,824,633 branch-misses # 1.26% of all branches ( +- 0.10% )
0.596246531 seconds time elapsed ( +- 0.07% )
~~~~~
After:
~~~~~
Performance counter stats for 'perf report --stdio --inline -g srcline -s srcline' (5 runs):
113.111405 task-clock (msec) # 0.990 CPUs utilized ( +- 0.89% )
29 context-switches # 0.255 K/sec ( +- 54.25% )
0 cpu-migrations # 0.000 K/sec
5,380 page-faults # 0.048 M/sec ( +- 0.01% )
432,378,779 cycles # 3.823 GHz ( +- 0.75% )
670,057,633 instructions # 1.55 insn per cycle ( +- 0.01% )
141,001,247 branches # 1246.570 M/sec ( +- 0.01% )
2,346,845 branch-misses # 1.66% of all branches ( +- 0.19% )
0.114222393 seconds time elapsed ( +- 1.19% )
~~~~~
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Reviewed-by: 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: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171019113836.5548-3-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The inline_node structs are maintained by the new dso->inlines tree.
This in turn keeps ownership of the fake symbols and srcline string
representing an inline frame.
This tree is sorted by address to allow quick lookups. All other entries
of the symbol beside the function name are unused for inline frames. The
advantage of this approach is that all existing users of the callchain
API can now transparently display inlined frames without having to patch
their code.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20171009203310.17362-6-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is mostly a preparation to enable the creation of full callchain
nodes for inline frames. Such frames will reference the IP of the
non-inlined frame, but hold the symbol and srcline for an inlined
location. As such, we won't be able to query the srcline on-demand based
on the IP alone. Instead, we will leverage the functionality provided by
this patch here, and store the srcline for the inlined nodes in the new
srcline member of callchain_cursor_node.
Note that this patch on its own leaks the srcline, as there is no
free_callchain_cursor_node or similar. A future patch will add caching
of the srcline and handle deletion properly.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20171009203310.17362-3-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The proc files which is sorted with alphabetical order are evenly
assigned to several synthesize threads to be processed in parallel.
For 'perf top', the threads number hard code to online CPU number. The
following patch will introduce an option to set it.
For other perf tools, the thread number is 1. Because the process
function is not ready for multithreading, e.g.
process_synthesized_event.
This patch series only support event synthesize multithreading for 'perf
top'. For other tools, it can be done separately later.
With multithread applied, the total processing time can get up to 1.56x
speedup on Knights Mill for 'perf top'.
For specific single event processing, the processing time could increase
because of the lock contention. So proc_map_timeout may need to be
increased. Otherwise some proc maps will be truncated.
Based on my test, increasing the proc_map_timeout has small impact
on the total processing time. The total processing time still get 1.49x
speedup on Knights Mill after increasing the proc_map_timeout.
The patch itself doesn't increase the proc_map_timeout.
Doesn't need to implement multithreading for per task monitoring,
perf_event__synthesize_thread_map. It doesn't have performance issue.
Committer testing:
# getconf _NPROCESSORS_ONLN
4
# perf trace --no-inherit -e clone -o /tmp/output perf top
# tail -4 /tmp/bla
0.124 ( 0.041 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3eb3a8f30, parent_tidptr: 0x7fc3eb3a99d0, child_tidptr: 0x7fc3eb3a99d0, tls: 0x7fc3eb3a9700) = 9548 (perf)
0.246 ( 0.023 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3eaba7f30, parent_tidptr: 0x7fc3eaba89d0, child_tidptr: 0x7fc3eaba89d0, tls: 0x7fc3eaba8700) = 9549 (perf)
0.286 ( 0.019 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3ea3a6f30, parent_tidptr: 0x7fc3ea3a79d0, child_tidptr: 0x7fc3ea3a79d0, tls: 0x7fc3ea3a7700) = 9550 (perf)
246.540 ( 0.047 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3ea3a6f30, parent_tidptr: 0x7fc3ea3a79d0, child_tidptr: 0x7fc3ea3a79d0, tls: 0x7fc3ea3a7700) = 9551 (perf)
#
Signed-off-by: Kan Liang <kan.liang@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1506696477-146932-4-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Andi reported a performance drop in single threaded perf tools such as
'perf script' due to the growing number of locks being put in place to
allow for multithreaded tools, so wrap the POSIX threads rwlock routines
with the names used for such kinds of locks in the Linux kernel and then
allow for tools to ask for those locks to be used or not.
I.e. a tool may have a multithreaded phase and then switch to single
threaded, like the upcoming patches for the synthesizing of
PERF_RECORD_{FORK,MMAP,etc} for pre-existing processes to then switch to
single threaded mode in 'perf top'.
The init routines will not be conditional, this way starting as single
threaded to then move to multi threaded mode should be possible.
Reported-by: Andi Kleen <ak@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170404161739.GH12903@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In some cases we already have calculated the hash bucket, so reuse it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-800zehjsyy03er4s4jf0e99v@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To process any events, it needs to find the thread in the machine first.
The machine maintains a rb tree to store all threads. The rb tree is
protected by a rw lock.
It is not a problem for current perf which serially processing events.
However, it will have scalability performance issue to process events in
parallel, especially on a heavy load system which have many threads.
Introduce a hashtable to divide the big rb tree into many samll rb tree
for threads. The index is thread id % hashtable size. It can reduce the
lock contention.
Committer notes:
Renamed some variables and function names to reduce semantic confusion:
'struct threads' pointers: thread -> threads
threads hastable index: tid -> hash_bucket
struct threads *machine__thread() -> machine__threads()
Cast tid to (unsigned int) to handle -1 in machine__threads() (Kan Liang)
Signed-off-by: Kan Liang <kan.liang@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1505096603-215017-2-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a new sort option "phys_daddr" for --mem-mode sort. With this
option applied, perf can sort and report by sample's physical address.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1504026672-7304-3-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The branch history code has a loop detection function. With this, we can
get the number of iterations by calculating the removed loops.
While it would be nice for knowing the average cycles of iterations.
This patch adds up the cycles in branch entries of removed loops and
save the result to the next branch entry (e.g. branch entry A).
Finally it will display the iteration number and average cycles at the
"from" of branch entry A.
For example:
perf record -g -j any,save_type ./div
perf report --branch-history --no-children --stdio
--22.63%--main div.c:42 (RET CROSS_2M)
compute_flag div.c:28 (cycles:2 iter:173115 avg_cycles:2)
|
--10.73%--compute_flag div.c:27 (RET CROSS_2M)
rand rand.c:28 (cycles:1)
rand rand.c:28 (RET CROSS_2M)
__random random.c:298 (cycles:1)
__random random.c:297 (COND_BWD CROSS_2M)
__random random.c:295 (cycles:1)
__random random.c:295 (COND_BWD CROSS_2M)
__random random.c:295 (cycles:1)
__random random.c:295 (RET CROSS_2M)
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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/1502111115-18305-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
During work on perf report for s390 I ran into the following issue:
0 0x318 [0x78]: PERF_RECORD_MMAP -1/0:
[0x3ff804d6990(0xfffffc007fb2966f) @ 0]:
x /lib/modules/4.12.0perf1+/kernel/drivers/s390/net/qeth_l2.ko
This is a PERF_RECORD_MMAP entry of the perf.data file with an invalid
module size for qeth_l2.ko (the s390 ethernet device driver).
Even a mainframe does not have 0xfffffc007fb2966f bytes of main memory.
It turned out that this wrong size is created by the perf record
command. What happens is this function call sequence from
__cmd_record():
perf_session__new():
perf_session__create_kernel_maps():
machine__create_kernel_maps():
machine__create_modules(): Creates map for all loaded kernel modules.
modules__parse(): Reads /proc/modules and extracts module name and
load address (1st and last column)
machine__create_module(): Called for every module found in /proc/modules.
Creates a new map for every module found and enters
module name and start address into the map. Since the
module end address is unknown it is set to zero.
This ends up with a kernel module map list sorted by module start
addresses. All module end addresses are zero.
Last machine__create_kernel_maps() calls function map_groups__fixup_end().
This function iterates through the maps and assigns each map entry's
end address the successor map entry start address. The last entry of the
map group has no successor, so ~0 is used as end to consume the remaining
memory.
Later __cmd_record calls function record__synthesize() which in turn calls
perf_event__synthesize_kernel_mmap() and perf_event__synthesize_modules()
to create PERF_REPORT_MMAP entries into the perf.data file.
On s390 this results in the last module qeth_l2.ko
(which has highest start address, see module table:
[root@s8360047 perf]# cat /proc/modules
qeth_l2 86016 1 - Live 0x000003ff804d6000
qeth 266240 1 qeth_l2, Live 0x000003ff80296000
ccwgroup 24576 1 qeth, Live 0x000003ff80218000
vmur 36864 0 - Live 0x000003ff80182000
qdio 143360 2 qeth_l2,qeth, Live 0x000003ff80002000
[root@s8360047 perf]# )
to be the last entry and its map has an end address of ~0.
When the PERF_RECORD_MMAP entry is created for kernel module qeth_l2.ko
its start address and length is written. The length is calculated in line:
event->mmap.len = pos->end - pos->start;
and results in 0xffffffffffffffff - 0x3ff804d6990(*) = 0xfffffc007fb2966f
(*) On s390 the module start address is actually determined by a __weak function
named arch__fix_module_text_start() in machine__create_module().
I think this improvable. We can use the module size (2nd column of /proc/modules)
to get each loaded kernel module size and calculate its end address.
Only for map entries which do not have a valid end address (end is still zero)
we can use the heuristic we have now, that is use successor start address or ~0.
Signed-off-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
LPU-Reference: 20170803134902.47207-2-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-nmoqij5b5vxx7rq2ckwu8iaj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf record -b -g <command>
perf report --branch-history
This merges the LBRs with the callgraphs.
However it would be nice if it also works without callgraphs (-g) set in
perf record, so that only the LBRs are displayed. But currently perf
report errors in this case. For example,
perf record -b <command>
perf report --branch-history
Error:
Selected -g or --branch-history but no callchain data. Did
you call 'perf record' without -g?
This patch displays the LBRs only even if callgraphs(-g) is not enabled
in perf record.
Change log:
v2: According to Milian Wolff's comment, change the obsolete error
message. Now the error message is:
┌─Error:─────────────────────────────────────┐
│Selected -g or --branch-history. │
│But no callchain or branch data. │
│Did you call 'perf record' without -g or -b?│
│ │
│ │
│Press any key... │
└────────────────────────────────────────────┘
When passing the last parameter to hists__fprintf,
changes "|" to "||".
hists__fprintf(hists, !quiet, 0, 0, rep->min_percent, stdout,
symbol_conf.use_callchain || symbol_conf.show_branchflag_count);
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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/1494240182-28899-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Show branch type in callchain entry. The branch type is printed
with other LBR information (such as cycles/abort/...).
For example:
perf record -g -j any,save_type
perf report --branch-history --stdio --no-children
38.50% div.c:45 [.] main div
|
---main div.c:42 (RET CROSS_2M cycles:2)
compute_flag div.c:28 (cycles:2)
compute_flag div.c:27 (RET CROSS_2M cycles:1)
rand rand.c:28 (cycles:1)
rand rand.c:28 (RET CROSS_2M cycles:1)
__random random.c:298 (cycles:1)
__random random.c:297 (COND_BWD CROSS_2M cycles:1)
__random random.c:295 (cycles:1)
__random random.c:295 (COND_BWD CROSS_2M cycles:1)
__random random.c:295 (cycles:1)
__random random.c:295 (RET CROSS_2M cycles:9)
Change log
v6: Remove the branch_type_str() since it's moved to branch.c.
v5: Rewrite the branch info print code in util/callchain.c.
v4: Comparing to previous version, the major changes are:
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1500379995-6449-8-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If a stripped binary is placed in the cache, the user is in a situation
where there's a cached elf file present, but it doesn't have any symtab
to use for name resolution. Grab the debuginfo for binaries that don't
end in .ko. This yields a better chance of resolving symbols from older
traces.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-7-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If a process is in a mountns and has symbols in /tmp/perf-<pid>.map,
look first in the namespace using the tgid for the pidns that the
process might be in. If the map isn't found there, try looking in the
mountns where perf is running, and use the tgid that's appropriate for
perf's pid namespace. If all else fails, use the original pid.
This allows us to locate a symbol map file in the mount namespace, if it
was generated there. However, we also try the tool's /tmp in case it's
there instead.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-3-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Which is the case in S/390, where symbols were not being resolved
because machine__get_kernel_start was only setting machine->kernel_start
when the just successfully loaded kernel symtab had its map->start set
to !0, when it was left at (1ULL << 63) assuming a partitioning of the
address space for user/kernel, which is not the case in S/390 nor in
Sparc.
So just check if map__load() was successfull and set
machine->kernel_start to zero, fixing kernel symbol resolution on S/390.
Test performed by Thomas:
----
I like this patch. I have done a new build and removed all my debug output to start
from scratch. Without your patch I get this:
# Samples: 4 of event 'cpu-clock'
# Event count (approx.): 1000000
#
# Children Self Command Shared Object Symbol
# ........ ........ ....... ................ ........................
75.00% 0.00% true [unknown] [k] 0x00000000004bedda
|
---0x4bedda
|
|--50.00%--0x42693a
| |
| --25.00%--0x2a72e0
| 0x2af0ca
| 0x3d1003fe4c0
|
--25.00%--0x4272bc
0x26fa84
and with your patch (I just rebuilt the perf tool, nothing else and used the same
perf.data file as input):
# Samples: 4 of event 'cpu-clock'
# Event count (approx.): 1000000
#
# Children Self Command Shared Object Symbol
# ........ ........ ....... .......................... ..................................
75.00% 0.00% true [kernel.vmlinux] [k] pgm_check_handler
|
---pgm_check_handler
do_dat_exception
handle_mm_fault
__handle_mm_fault
filemap_map_pages
|
|--25.00%--rcu_read_lock_held
| rcu_lockdep_current_cpu_online
| 0x3d1003ff4c0
|
--25.00%--lock_release
Looks good to me....
----
Reported-and-Tested-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Link: http://lkml.kernel.org/n/tip-dk0n1uzmbe0tbthrpfqlx6bz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Michael reported the segfault when kernel.kptr_restrict=2 is set.
$ perf record ls
...
perf: Segmentation fault
Obtained 16 stack frames.
./perf(dump_stack+0x2d) [0x5068df]
./perf(sighandler_dump_stack+0x2d) [0x5069bf]
./perf() [0x43e47b]
/lib64/libc.so.6(+0x3594f) [0x7f762004794f]
/lib64/libc.so.6(strlen+0x26) [0x7f762009ef86]
/lib64/libc.so.6(__strdup+0xd) [0x7f762009ecbd]
./perf(maps__set_kallsyms_ref_reloc_sym+0x4d) [0x51590f]
./perf(machine__create_kernel_maps+0x136) [0x50a7de]
./perf(perf_session__create_kernel_maps+0x2c) [0x510a81]
./perf(perf_session__new+0x13d) [0x510e23]
./perf() [0x43fd61]
./perf(cmd_record+0x704) [0x441823]
./perf() [0x4bc1a0]
./perf() [0x4bc40d]
./perf() [0x4bc55f]
./perf(main+0x2d5) [0x4bc939]
Segmentation fault (core dumped)
The reason is that with kernel.kptr_restrict=2, we don't get
the symbol from machine__get_running_kernel_start, which we
want to use in maps__set_kallsyms_ref_reloc_sym and we crash.
Check the symbol name value before calling
maps__set_kallsyms_ref_reloc_sym() and succeed without ref_reloc_sym
being set. It's safe because we check its existence before we use it.
Reported-by: Michael Petlan <mpetlan@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170626095153.553-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Like machine__findnew_module_dso(), it should set necessary info for
kernel modules to find symbol info from the file. Factor out
dso__set_module_info() to do it.
This is needed for dso__needs_decompress() to detect such DSOs.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170531120105.21731-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That is the case of _text on s390, and we have some functions that return an
address, using address zero to report problems, oops.
This would lead the symbol loading routines to not use "_text" as the reference
relocation symbol, or the first symbol for the kernel, but use instead
"_stext", that is at the same address on x86_64 and others, but not on s390:
[acme@localhost perf-4.11.0-rc6]$ head -15 /proc/kallsyms
0000000000000000 T _text
0000000000000418 t iplstart
0000000000000800 T start
000000000000080a t .base
000000000000082e t .sk8x8
0000000000000834 t .gotr
0000000000000842 t .cmd
0000000000000846 t .parm
000000000000084a t .lowcase
0000000000010000 T startup
0000000000010010 T startup_kdump
0000000000010214 t startup_kdump_relocated
0000000000011000 T startup_continue
00000000000112a0 T _ehead
0000000000100000 T _stext
[acme@localhost perf-4.11.0-rc6]$
Which in turn would make 'perf test vmlinux' to fail because it wouldn't find
the symbols before "_stext" in kallsyms.
Fix it by using the return value only for errors and storing the
address, when the symbol is successfully found, in a provided pointer
arg.
Before this patch:
After:
[acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
test child forked, pid 40693
Looking at the vmlinux_path (8 entries long)
Using /usr/lib/debug/lib/modules/3.10.0-654.el7.s390x/vmlinux for symbols
ERR : 0: _text not on kallsyms
ERR : 0x418: iplstart not on kallsyms
ERR : 0x800: start not on kallsyms
ERR : 0x80a: .base not on kallsyms
ERR : 0x82e: .sk8x8 not on kallsyms
ERR : 0x834: .gotr not on kallsyms
ERR : 0x842: .cmd not on kallsyms
ERR : 0x846: .parm not on kallsyms
ERR : 0x84a: .lowcase not on kallsyms
ERR : 0x10000: startup not on kallsyms
ERR : 0x10010: startup_kdump not on kallsyms
ERR : 0x10214: startup_kdump_relocated not on kallsyms
ERR : 0x11000: startup_continue not on kallsyms
ERR : 0x112a0: _ehead not on kallsyms
<SNIP warnings>
test child finished with -1
---- end ----
vmlinux symtab matches kallsyms: FAILED!
[acme@localhost perf-4.11.0-rc6]$
After:
[acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
test child forked, pid 47160
<SNIP warnings>
test child finished with 0
---- end ----
vmlinux symtab matches kallsyms: Ok
[acme@localhost perf-4.11.0-rc6]$
Reported-by: Michael Petlan <mpetlan@redhat.com>
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: http://lkml.kernel.org/n/tip-9x9bwgd3btwdk1u51xie93fz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The users of regex and fnmatch functions should include those headers
instead.
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: http://lkml.kernel.org/n/tip-ixzm5kuamsq1ixbkuv6kmwzj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The files using the dirent.h routines should instead include it,
reducing the includes hell that lead to longer build times.
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: http://lkml.kernel.org/n/tip-42g2f4z6nfg7mdb2ae97n7tj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Removing it from util.h, part of an effort to disentangle the includes
hell, that makes changes to util.h or something included by it to cause
a complete rebuild of the tools.
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: http://lkml.kernel.org/n/tip-ztrjy52q1rqcchuy3rubfgt2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
More stuff that came from git, out of the hodge-podge that is util.h
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: http://lkml.kernel.org/n/tip-e3lana4gctz3ub4hn4y29hkw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Needed to use the PRI[xu](32,64) formatting macros.
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: http://lkml.kernel.org/n/tip-wkbho8kaw24q67dd11q0j39f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce a new option to record PERF_RECORD_NAMESPACES events emitted
by the kernel when fork, clone, setns or unshare are invoked. And update
perf-record documentation with the new option to record namespace
events.
Committer notes:
Combined it with a later patch to allow printing it via 'perf report -D'
and be able to test the feature introduced in this patch. Had to move
here also perf_ns__name(), that was introduced in another later patch.
Also used PRIu64 and PRIx64 to fix the build in some enfironments wrt:
util/event.c:1129:39: error: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'long long unsigned int' [-Werror=format=]
ret += fprintf(fp, "%u/%s: %lu/0x%lx%s", idx
^
Testing it:
# perf record --namespaces -a
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.083 MB perf.data (423 samples) ]
#
# perf report -D
<SNIP>
3 2028902078892 0x115140 [0xa0]: PERF_RECORD_NAMESPACES 14783/14783 - nr_namespaces: 7
[0/net: 3/0xf0000081, 1/uts: 3/0xeffffffe, 2/ipc: 3/0xefffffff, 3/pid: 3/0xeffffffc,
4/user: 3/0xeffffffd, 5/mnt: 3/0xf0000000, 6/cgroup: 3/0xeffffffb]
0x1151e0 [0x30]: event: 9
.
. ... raw event: size 48 bytes
. 0000: 09 00 00 00 02 00 30 00 c4 71 82 68 0c 7f 00 00 ......0..q.h....
. 0010: a9 39 00 00 a9 39 00 00 94 28 fe 63 d8 01 00 00 .9...9...(.c....
. 0020: 03 00 00 00 00 00 00 00 ce c4 02 00 00 00 00 00 ................
<SNIP>
NAMESPACES events: 1
<SNIP>
#
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/148891930386.25309.18412039920746995488.stgit@hbathini.in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter.
This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Kook <keescook@chromium.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-9-git-send-email-elena.reshetova@intel.com
[ Did missing conversion in __machine__remove_thread() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In a few cases we were using 'enum map_type' and that triggered this
warning when using clang:
util/session.c:1923:16: error: comparison of constant 2 with expression of type 'enum map_type' is always true
[-Werror,-Wtautological-constant-out-of-range-compare]
for (i = 0; i < MAP__NR_TYPES; ++i) {
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: http://lkml.kernel.org/n/tip-i6uyo6bsopa2dghnx8qo7rri@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As it is an array, so will always evaluate to 'true', as reported by
clang:
builtin-sched.c:2070:19: error: address of array 'sym->name' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion]
if (sym && sym->name) {
~~ ~~~~~^~~~
1 warning generated.
So just ditch all those useless checks.
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: http://lkml.kernel.org/n/tip-ydpm927col06paixb775jjx5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To reduce the boilerplate for searching for functions in the running
kernel and modules.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-93iqzayafpaxaguoiwjqezgz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since the branch ip has been added to call stack for easier browsing,
this patch adds more branch information. For example, add a flag to
indicate if this ip is a branch, and also add with the branch flag.
Then we can know if the cursor node represents a branch and know what
the branch flag it has.
The branch history code has a loop detection pass that removes loops. It
would be nice for knowing how many loops were removed then in next
steps, we can compute out the average number of iterations.
For example:
Before remove_loops(),
entry0: from = 0x100, to = 0x200
entry1: from = 0x300, to = 0x250
entry2: from = 0x300, to = 0x250
entry3: from = 0x300, to = 0x250
entry4: from = 0x700, to = 0x800
After remove_loops()
entry0: from = 0x100, to = 0x200
entry1: from = 0x300, to = 0x250
entry2: from = 0x700, to = 0x800
The original entry2 and entry3 are removed. So the number of iterations
(from = 0x300, to = 0x250) is equal to removed number + 1 (2 + 1).
iterations = removed number + 1;
average iteractions = Sum(iteractions) / number of samples
This formula ignores other cases, for example, iterations cross multiple
buffers and one buffer contains 2+ loops. Because in practice, it's good
enough.
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/n/1477876794-30749-2-git-send-email-yao.jin@linux.intel.com
[ Renamed 'iter' to 'nr_loop_iter' for clarity ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Experimenting a bit using cppcheck[1], a static checker brought to my
attention by Colin, reducing the scope of some variables, reducing the
line of source code lines in the process:
$ cppcheck --enable=style tools/perf/util/thread.c
Checking tools/perf/util/thread.c...
[tools/perf/util/thread.c:17]: (style) The scope of the variable 'leader' can be reduced.
[tools/perf/util/thread.c:133]: (style) The scope of the variable 'err' can be reduced.
[tools/perf/util/thread.c:273]: (style) The scope of the variable 'err' can be reduced.
Will continue later, but these are already useful, keep them.
1: https://sourceforge.net/p/cppcheck/wiki/Home/
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Colin Ian King <colin.king@canonical.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: http://lkml.kernel.org/n/tip-ixws7lbycihhpmq9cc949ti6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We're not using it anymore, few users were, but we really could do
without it, simplify lots of functions by removing it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-1zng8wdznn00iiz08bb7q3vn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Including machines__set_symbol_filter(), not used anymore.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-7o1qgmrpvzuis4a9f0t8mnri@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
At present, when creating module's map, perf gets 'start' address by
parsing '/proc/modules', but it's the module base address, it isn't the
start address of the '.text' section.
In most arches, it's OK. But for s390, it places 'GOT' and 'PLT'
relocations before '.text' section. So there exists an offset between
module base address and '.text' section, which will incur wrong symbol
resolution for modules.
Fix this bug by getting 'start' address of module's map from parsing
'/sys/module/[module name]/sections/.text', not from '/proc/modules'.
Signed-off-by: Song Shan Gong <gongss@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1469070651-6447-2-git-send-email-gongss@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And do nothing, just like free(), to avoid having to test it in callers,
usually in error paths.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-q42gj3b3znhho9z1mrbo4jce@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
User visible:
- Support cross unwinding, i.e. collecting '--call-graph dwarf' perf.data files
in one machine and then doing analysis in another machine of a different
hardware architecture. This enables, for instance, to do:
perf record -a --call-graph dwarf
on a x86-32 or aarch64 system and then do 'perf report' on it on a
x86_64 workstation. (He Kuang)
- Fix crash in build_id_cache__kallsyms_path(), recent regression (Wang Nan)
Infrastructure:
- Make tools/lib/bpf use the IS_ERR return facility consistently and also stop
using the _get_ term for non-reference count methods (Arnaldo Carvalho de Melo)
- 'perf config' refactorings (Taeung Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=DvZE
-----END PGP SIGNATURE-----
Merge tag 'perf-core-for-mingo-20160607' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Support cross unwinding, i.e. collecting '--call-graph dwarf' perf.data files
in one machine and then doing analysis in another machine of a different
hardware architecture. This enables, for instance, to do:
perf record -a --call-graph dwarf
on a x86-32 or aarch64 system and then do 'perf report' on it on a
x86_64 workstation. (He Kuang)
- Fix crash in build_id_cache__kallsyms_path(), recent regression (Wang Nan)
Infrastructure changes:
- Make tools/lib/bpf use the IS_ERR return facility consistently and also stop
using the _get_ term for non-reference count methods (Arnaldo Carvalho de Melo)
- 'perf config' refactorings (Taeung Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
To determine the libunwind methods to use, we should get the
32bit/64bit information from maps of a thread. When a thread is newly
created, the information is not prepared. This patch moves
unwind__prepare_access() into thread__insert_map() so we can get the
information we need from maps. Meanwhile, let thread__insert_map()
return value and show messages on error.
Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1464924803-22214-5-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf updates from Ingo Molnar:
"Mostly tooling and PMU driver fixes, but also a number of late updates
such as the reworking of the call-chain size limiting logic to make
call-graph recording more robust, plus tooling side changes for the
new 'backwards ring-buffer' extension to the perf ring-buffer"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
perf record: Read from backward ring buffer
perf record: Rename variable to make code clear
perf record: Prevent reading invalid data in record__mmap_read
perf evlist: Add API to pause/resume
perf trace: Use the ptr->name beautifier as default for "filename" args
perf trace: Use the fd->name beautifier as default for "fd" args
perf report: Add srcline_from/to branch sort keys
perf evsel: Record fd into perf_mmap
perf evsel: Add overwrite attribute and check write_backward
perf tools: Set buildid dir under symfs when --symfs is provided
perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced
perf annotate: Sort list of recognised instructions
perf annotate: Fix identification of ARM blt and bls instructions
perf tools: Fix usage of max_stack sysctl
perf callchain: Stop validating callchains by the max_stack sysctl
perf trace: Fix exit_group() formatting
perf top: Use machine->kptr_restrict_warned
perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1
perf machine: Do not bail out if not managing to read ref reloc symbol
perf/x86/intel/p4: Trival indentation fix, remove space
...
As thread__resolve_callchain_sample can be used for handling perf.data
files, that could've been recorded with a large max_stack sysctl setting
than what the system used for analysis has set.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-2995bt2g5yq2m05vga4kip6m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Hook into the libtraceevent plugin kernel symbol resolver to warn the
user that that can't happen with kptr_restrict=1.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9gc412xx1gl0lvqj1d1xwlyb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This means the user can't access /proc/kallsyms, for instance, because
/proc/sys/kernel/kptr_restrict is set to 1.
Instead leave the ref_reloc_sym as NULL and code using it will cope.
This allows 'perf trace' to work on such systems for !root, the only
issue would be when trying to resolve kernel symbols, which happens,
for instance, in some libtracevent plugins. A warning for that case
will be provided in the next patch in this series.
Noticed in Ubuntu 16.04, that comes with kptr_restrict=1.
Reported-by: Milian Wolff <milian.wolff@kdab.com>
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: http://lkml.kernel.org/n/tip-knpu3z4iyp2dxpdfm798fac4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The perf_sample->ip_callchain->nr value includes all the entries in the
ip_callchain->ip[] array, real addresses and PERF_CONTEXT_{KERNEL,USER,etc},
while what the user expects is that what is in the kernel.perf_event_max_stack
sysctl or in the upcoming per event perf_event_attr.sample_max_stack knob be
honoured in terms of IP addresses in the stack trace.
So match the kernel support and validate chain->nr taking into account
both kernel.perf_event_max_stack and kernel.perf_event_max_contexts_per_stack.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-mgx0jpzfdq4uq4abfa40byu0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Instead of using a raw string, use DSO__NAME_KALLSYMS and
DSO__NAME_KCORE macros for kallsyms and kcore.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160515031935.4017.50971.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The existing implementation of thread__resolve_callchain, under certain
circumstances, can assemble callchain entries in the incorrect order.
The callchain entries are resolved incorrectly for a sample when all of
the following conditions are met:
1. callchain_param.order is set to ORDER_CALLER
2. thread__resolve_callchain_sample is able to resolve callchain entries
for the sample.
3. unwind__get_entries is also able to resolve callchain entries for the
sample.
The fix is accomplished by reversing the order in which
thread__resolve_callchain_sample and unwind__get_entries are called when
callchain_param.order is set to ORDER_CALLER.
Unwind specific code from thread__resolve_callchain is also moved into a
new static function to improve readability of the fix.
How to Reproduce the Existing Bug:
Modifying perf script to print call trees in the opposite order or
applying the remaining patches from this series and comparing the
results output from export-to-postgtresql.py are the easiest ways to see
the bug, however it can still be seen in current builds using perf
report.
Here is how i can reproduce the bug using perf report:
# perf record --call-graph=dwarf stress -c 1 -t 5
when i run this command:
# perf report --call-graph=flat,0,0,callee
This callchain, containing kernel (handle_irq_event, etc) and userspace
samples (__libc_start_main, etc) is contained in the output, which looks
correct (callee order):
gen8_irq_handler
handle_irq_event_percpu
handle_irq_event
handle_edge_irq
handle_irq
do_IRQ
ret_from_intr
__random
rand
0x558f2a04dded
0x558f2a04c774
__libc_start_main
0x558f2a04dcd9
Now run this command using caller order:
# perf report --call-graph=flat,0,0,caller
It is expected to see the exact reverse of the above when using caller
order (with "0x558f2a04dcd9" at the top and "gen8_irq_handler" at the
bottom) in the output, but it is nowhere to be found.
instead you see this:
ret_from_intr
do_IRQ
handle_irq
handle_edge_irq
handle_irq_event
handle_irq_event_percpu
gen8_irq_handler
0x558f2a04dcd9
__libc_start_main
0x558f2a04c774
0x558f2a04dded
rand
__random
Notice how internally the kernel symbols are reversed and the user space
symbols are reversed, but the kernel symbols still appear above the user
space symbols.
if this patch is applied and perf script is re-run, you will see the
expected output (with "0x558f2a04dcd9" at the top and "gen8_irq_handler"
at the bottom):
0x558f2a04dcd9
__libc_start_main
0x558f2a04c774
0x558f2a04dded
rand
__random
ret_from_intr
do_IRQ
handle_irq
handle_edge_irq
handle_irq_event
handle_irq_event_percpu
gen8_irq_handler
Signed-off-by: Chris Phlipot <cphlipot0@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461831551-12213-2-git-send-email-cphlipot0@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.
Moving sort__has_parent into struct perf_hpp_list.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo