build_id_cache__kallsyms_path() accepts a string buffer but also allocs
a buffer using asnprintf. Unfortunately, the its only user passes it a
stack-allocated buffer. Freeing it causes crashes like this:
$ perf script
*** Error in `/home/wangnan/perf': free(): invalid pointer: 0x00007fffffff9630 ***
======= Backtrace: =========
lib64/libc.so.6(+0x6eeef)[0x7ffff5dbaeef]
lib64/libc.so.6(+0x78cae)[0x7ffff5dc4cae]
lib64/libc.so.6(+0x79987)[0x7ffff5dc5987]
/home/w00229757/perf(build_id_cache__kallsyms_path+0x6b)[0x49681b]
/home/w00229757/perf[0x4bdd40]
/home/w00229757/perf(dso__load+0xa3a)[0x4c048a]
/home/w00229757/perf(map__load+0x6f)[0x4d561f]
/home/w00229757/perf(thread__find_addr_map+0x235)[0x49e935]
/home/w00229757/perf(machine__resolve+0x7d)[0x49ec6d]
/home/w00229757/perf[0x4555a8]
/home/w00229757/perf[0x4d9507]
/home/w00229757/perf[0x4d9e80]
/home/w00229757/perf(ordered_events__flush+0x354)[0x4dd444]
/home/w00229757/perf(perf_session__process_events+0x3d0)[0x4dc140]
/home/w00229757/perf(cmd_script+0x12b0)[0x4592e0]
/home/w00229757/perf[0x4911f1]
/home/w00229757/perf(main+0x68f)[0x4352ef]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7ffff5d6dbd5]
/home/w00229757/perf[0x435415]
======= Memory map: ========
This patch simplifies build_id_cache__kallsyms_path(), not even
considering allocating a string buffer, so never frees anything. Its
caller should manage memory allocation.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Fixes: 01412261d9 ("perf buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid")
Link: http://lkml.kernel.org/r/1465271678-7392-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To try to, over time, consistently use the IS_ERR() interface instead of
using two return values, i.e. the integer return value for an error and
the pointer address to return the bpf_map->priv pointer.
Also rename it to bpf__priv(), to leave the "get" term for reference
counting.
Noticed while working on using BPF for collecting non-integer syscall
argument payloads (struct sockaddr in calls such as connect(), for
instance), where we need to use BPF maps and thus generalise
bpf__setup_stdout() to connect bpf_output events with maps in a bpf
proggie.
Acked-by: Wang Nan <wangnan0@huawei.com>
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>
Link: http://lkml.kernel.org/n/tip-saypxyd6ptrct379jqgxx4bl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If a config file has wrong key-value pairs, the perf process will be
forcibly terminated by die() at perf_parse_file() called by
perf_config() so terminal settings can be crushed because of unusual
termination.
For example:
If user config file has a wrong value 'red;default' instead of a normal
value like 'red, default' for a key 'colors.top',
# cat ~/.perfconfig
[colors]
medium = red;default # wrong value
and if running sub-command 'top',
# perf top
perf process is dead by force and terminal setting is broken
with a messge like below.
Fatal: bad config file line 2 in /root/.perfconfig
So fix it.
If perf_config() can return on failure without calling die()
at perf_parse_file(), this problem can be solved.
And if a config file has wrong values, show the error message
and then use default config values instead of wrong config values.
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1465210380-26749-2-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When in CSV mode --metric-only outputs an header, unlike the other
modes. Previously it did not properly print headers for the aggregation
columns, so the headers were actually shifted against the real values.
Fix this here by outputting the correct headers for CSV.
v2: Indent array.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1464119559-17203-4-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When --metric-only is enabled there were no headers for the topology in
interval mode. Also when headers were printed they were on a separate
line.
Before:
$ perf stat --metric-only -A -I 1000 -a
1.001038376 frontend cycles idle insn per cycle stalled cycles per insn branch-misses of all branches
1.001038376 CPU0 123.54% 0.23 5.29 7.61%
1.001038376 CPU1 137.78% 0.24 5.13 10.07%
1.001038376 CPU2 64.48% 0.22 5.50 6.84%
After:
$ perf stat --metric-only -A -I 1000 -a
1.001111114 CPU0 82.46% 0.32 2.60 7.64%
1.001111114 CPU1 126.63% 0.02 42.83 0.15%
1.001111114 CPU2 193.54% 0.32 2.59 6.92%
v2: Move all headers on a single line
Reported-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1464119559-17203-3-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Implement the TopDown formulas in 'perf stat'. The topdown basic metrics
reported by the kernel are collected, and the formulas are computed and
output as normal metrics.
See the kernel commit exporting the events for details on the used
metrics.
Committer note:
Output example:
# perf stat --topdown -a usleep 1
Performance counter stats for 'system wide':
retiring bad speculation frontend bound backend bound
S0-C0 2 23.8% 11.6% 28.3% 36.3%
S0-C1 2 16.2% 15.7% 36.5% 31.6%
0.000579956 seconds time elapsed
#
v2: Always print all metrics, only use thresholds for coloring.
v3: Mark retiring over threshold green, not red.
v4: Only print one decimal digit
Fix color printing of one metric
v5: Avoid printing -0.0
v6: Remove extra frontend event lookup
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1464119559-17203-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add basic plumbing for TopDown in perf stat
TopDown is intended to replace the frontend cycles idle/ backend cycles
idle metrics in standard perf stat output. These metrics are not
reliable in many workloads, due to out of order effects.
This implements a new --topdown mode in perf stat (similar to
--transaction) that measures the pipe line bottlenecks using
standardized formulas. The measurement can be all done with 5 counters
(one fixed counter)
The result are four metrics:
FrontendBound, BackendBound, BadSpeculation, Retiring
that describe the CPU pipeline behavior on a high level.
The full top down methology has many hierarchical metrics. This
implementation only supports level 1 which can be collected without
multiplexing. A full implementation of top down on top of perf is
available in pmu-tools toplev. (http://github.com/andikleen/pmu-tools)
The current version works on Intel Core CPUs starting with Sandy Bridge,
and Atom CPUs starting with Silvermont. In principle the generic
metrics should be also implementable on other out of order CPUs.
TopDown level 1 uses a set of abstracted metrics which are generic to
out of order CPU cores (although some CPUs may not implement all of
them):
topdown-total-slots Available slots in the pipeline
topdown-slots-issued Slots issued into the pipeline
topdown-slots-retired Slots successfully retired
topdown-fetch-bubbles Pipeline gaps in the frontend
topdown-recovery-bubbles Pipeline gaps during recovery
from misspeculation
These metrics then allow to compute four useful metrics:
FrontendBound, BackendBound, Retiring, BadSpeculation.
Add a new --topdown options to enable events. When --topdown is
specified set up events for all topdown events supported by the kernel.
Add topdown-* as a special case to the event parser, as is needed for
all events containing -.
The actual code to compute the metrics is in follow-on patches.
v2: Use standard sysctl read function.
v3: Move x86 specific code to arch/
v4: Enable --metric-only implicitly for topdown.
v5: Add --single-thread option to not force per core mode
v6: Fix output order of topdown metrics
v7: Allow combining with -d
v8: Remove --single-thread again
v9: Rename functions, adding arch_ and topdown_.
v10: Expand man page and describe TopDown better
Paste intro into commit description.
Print error when malloc fails.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1464119559-17203-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's a display inconsistency when there are multiple tracepoint
events, some of which have the 'call-graph' config option set but the
first one hasn't, i.e. the whole logic for call graph processing is
enabled only if the first tracepoint event has call-graph set.
For instance, if we record signal_deliver with call-graph and
signal_generate without:
$ perf record -g -a -e signal:signal_deliver -e signal:signal_generate/call-graph=no/
[ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
$ perf script
kworker/u2:1 13 [000] 6563.875949: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1313 grp=1 res=0 ff61cc __send_signal+0x3ec ([kernel.kallsyms])
perf 1313 [000] 6563.877584: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
7ffff314 get_signal+0x80007f0023a4 ([kernel.kallsyms])
7fffe358 do_signal+0x80007f002028 ([kernel.kallsyms])
7fffa5e8 exit_to_usermode_loop+0x80007f002053 ([kernel.kallsyms])
...
Then we exchange the order of these two events in commandline, and keep
signal_generate without call-graph.
$ perf record -g -a -e signal:signal_generate/call-graph=no/ -e signal:signal_deliver
[ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
$ perf script
kworker/u2:2 1314 [000] 6933.353060: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1321 grp=1 res=0
perf 1321 [000] 6933.353872: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
This time, the callchain of the event signal_deliver disappeared. The
problem is caused by that perf only checks for the first evsel in evlist
and decides if callchain should be printed.
This patch traverses all evsels in evlist to see if any of them have
callchains, and shows the right result:
$ perf script
kworker/u2:2 1314 [000] 6933.353060: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1321 grp=1 res=0 ff61cc __send_signal+0x3ec ([kernel.kallsyms])
perf 1321 [000] 6933.353872: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
7ffff314 get_signal+0x80007f0023a4 ([kernel.kallsyms])
7fffe358 do_signal+0x80007f002028 ([kernel.kallsyms])
7fffa5e8 exit_to_usermode_loop+0x80007f002053 ([kernel.kallsyms])
...
Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1463374279-97209-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no need to receive events from overwritable ring buffer.
Instead, perf should make them run in background until some external
event of interest takes place. This patch makes ignores normal events from
overwrite evlists.
Overwritable events must be mapped readonly and backward, so if evlist
and evsel doesn't match (evsel->overwrite is true but either evlist is
read/write or evlist is not backward, and vice versa), skip mapping it.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1464056944-166978-3-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
[ Split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before this patch, a simple 'perf record' could fail if kptr_restrict is
set to 1 (for normal user) or 2 (for root):
# perf record ls
WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted,
check /proc/sys/kernel/kptr_restrict.
Samples in kernel functions may not be resolved if a suitable vmlinux
file is not found in the buildid cache or in the vmlinux path.
Samples in kernel modules won't be resolved at all.
If some relocation was applied (e.g. kexec) symbols may be misresolved
even with a suitable vmlinux or kallsyms file.
Segmentation fault (core dumped)
This patch skips perf_event__synthesize_kernel_mmap() when kptr is not
available.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes: 45e9005690 ("perf machine: Do not bail out if not managing to read ref reloc symbol")
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1464081688-167940-2-git-send-email-wangnan0@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
...
record__mmap_read() writes data from ring buffer into perf.data. 'head'
is maintained by the kernel, points to the last written record.
'old' is maintained by perf, points to the record read in previous
round. record__mmap_read() saves data from 'old' to 'head' to
perf.data.
The names of these variables are not very intutive. In addition,
when dealing with backward writing ring buffer, the md->prev pointer
should point to 'head' instead of the last byte it got.
Add 'start' and 'end' pointer to make code clear and set md->prev to
'head' instead of the moved 'old' pointer. This patch doesn't change
behavior since:
buf = &data[old & md->mask];
size = head - old;
old += size; <--- Here, old == head
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1463987628-163563-4-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
