The kernel now supports the disabling of branch tracing, however the
decoder assumes branch tracing is always enabled. Pass through a parameter
to indicate whether branch tracing is enabled and use it to avoid cases
when the decoder is expecting branch packets. There are 2 such cases.
First, FUP packets which can bind to an IP even when there is no branch
tracing. Secondly, the decoder will try to use branch packets to find an IP
to start decoding or to recover from errors.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1495786658-18063-11-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Intel PT uses IP compression based on the last IP. For decoding
purposes, 'last IP' is considered to be reset to zero whenever there is
a synchronization packet (PSB). The decoder wasn't doing that, and was
treating the zero value to mean that there was no last IP, whereas
compression can be done against the zero value. Fix by setting last_ip
to zero when a PSB is received and keep track of have_last_ip.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1495786658-18063-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Porting PPC to libdw only needs an architecture-specific hook to move
the register state from perf to libdw.
The ARM and x86 architectures already use libdw, and it is useful to
have as much common code for the unwinder as possible. Mark Wielaard
has contributed a frame-based unwinder to libdw, so that unwinding works
even for binaries that do not have CFI information. In addition,
libunwind is always preferred to libdw by the build machinery so this
cannot introduce regressions on machines that have both libunwind and
libdw installed.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1496312681-20133-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Implementing a new --smi-cost mode in perf stat to measure SMI cost.
During the measurement, the /sys/device/cpu/freeze_on_smi will be set.
The measurement can be done with one counter (unhalted core cycles), and
two free running MSR counters (IA32_APERF and SMI_COUNT).
In practice, the percentages of SMI core cycles should be more useful
than absolute value. So the output will be the percentage of SMI core
cycles and SMI#. metric_only will be set by default.
SMI cycles% = (aperf - unhalted core cycles) / aperf
Here is an example output.
Performance counter stats for 'sudo echo ':
SMI cycles% SMI#
0.1% 1
0.010858678 seconds time elapsed
Users who wants to get the actual value can apply additional
--no-metric-only.
Signed-off-by: Kan Liang <Kan.liang@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1495825538-5230-3-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This test checks the response of the system clock to frequency
steps made with adjtimex(). The frequency error and stability of
the CLOCK_MONOTONIC clock relative to the CLOCK_MONOTONIC_RAW clock
is measured in two intervals following the step. The test fails if
values from the second interval exceed specified limits.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Add the beginnings of a testsuite for tc functionality in the kernel.
These are a series of unit tests that use the tc executable and verify
the success of those commands by checking both the exit codes and the
output from tc's 'show' operation.
To run the tests:
# cd tools/testing/selftests/tc-testing
# sudo ./tdc.py
You can specify the tc executable to use with the -p argument on the command
line or editing the 'TC' variable in tdc_config.py. Refer to the README for
full details on how to run.
The initial complement of test cases are limited mostly to tc actions. Test
cases are most welcome; see the creating-testcases subdirectory for help
in creating them.
Signed-off-by: Lucas Bates <lucasb@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While trying to reduce util.[ch] I noticed that fetch_kernel_version()
and fetch_ubuntu_kernel_version() do lots of operations only to check if
they are needed, i.e. it checks if the pointer where to return the
kernel version is NULL only after obtaining the kernel version from
/proc/version_signature or by parsing the results from uname().
Do it earlier not to confuse people reading this code in the future :-)
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-i94qwyekk4tzbu0b9ce1r1mz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Allow adding and removing fields to the default 'perf script' columns,
using + or - as field prefixes to do so (Andi Kleen)
- Display titles in left frame in the annotate browser (Jin Yao)
- Allow resolving the DSO name with 'perf script -F brstack{sym,off},dso'
(Mark Santaniello)
- Support function filtering in 'perf ftrace' (Namhyung Kim)
- Allow specifying function call depth in 'perf ftrace' (Namhyumg Kim)
Infrastructure changes:
- Adopt __noreturn, __printf, __scanf, noinline, __packed and __aligned
__alignment__(()) markers, to make the tools/ source code base to be
more compact and look more like kernel code (Arnaldo Carvalho de Melo)
- Remove unnecessary check in annotate_browser_write() (Jin Yao)
- Return arch from symbol__disassemble() so that callers, such as
the annotate TUI browser to use arch specific formattings, such
as the upcoming instruction micro-op fusion on Intel Core (Jin Yao)
- Remove superfluous check before use in the coresight code base (Kim
Phillips)
- Remove unused SAMPLE_SIZE defines and BTS priv array (Kim Phillips)
- Error handling fix/tidy ups in 'perf config' (Taeung Song)
- Avoid error in the BPF proggie built with clang in 'perf test llvm'
when PROFILE_ALL_BRANCHES is set (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Felipe writes:
usb: changes for v4.13 merge window
This time around we have a total of 57 non-merge commits. A list of
most important changes follows:
- Improvements to dwc3 tracing interface
- Initial dual-role support for dwc3
- Improvements to how we handle DMA resources in dwc3
- A new f_uac1 implementation which much more flexible
- Removal of AVR32 bits
- Improvements to f_mass_storage driver
The idea here is to make AutoFDO easier in cloud environment with ASLR.
It's easiest to show how this is useful by example. I built a small test
akin to "while(1) { do_nothing(); }" where the do_nothing function is
loaded from a dso:
$ cat burncpu.cpp
#include <dlfcn.h>
int main() {
void* handle = dlopen("./dso.so", RTLD_LAZY);
if (!handle) return -1;
typedef void (*fp)();
fp do_nothing = (fp) dlsym(handle, "do_nothing");
while(1) {
do_nothing();
}
}
$ cat dso.cpp
extern "C" void do_nothing() {}
$ cat build.sh
#!/bin/bash
g++ -shared dso.cpp -o dso.so
g++ burncpu.cpp -o burncpu -ldl
I sampled the execution of this program with perf record -b.
Using the existing "brstack,dso", we get absolute addresses that are
affected by ASLR, and could be different on different hosts. The address
does not uniquely identify a branch/target in the binary:
$ perf script -F brstack,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
0x7f967139b6aa(/tmp/burncpu/dso.so)/0x4006b1(/tmp/burncpu/exe)/P/-/-/0
Using the existing "brstacksym,dso" is a little better, because the
symbol plus offset and dso name *does* uniquely identify a branch/target
in the binary. Ultimately, however, AutoFDO wants a simple offset into
the binary, so we'd have to undo all the work perf did to symbolize in
the first place:
$ perf script -F brstacksym,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
do_nothing+0x5(/tmp/burncpu/dso.so)/main+0x44(/tmp/burncpu/exe)/P/-/-/0
With the new "brstackoff,dso" we get what we need: a simple offset into a
specific dso/binary that uniquely identifies a branch/target:
$ perf script -F brstackoff,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
0x6aa(/tmp/burncpu/dso.so)/0x4006b1(/tmp/burncpu/exe)/P/-/-/0
Signed-off-by: Mark Santaniello <marksan@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170619163825.2012979-2-marksan@fb.com
[ Updated documentation about 'brstackoff' using text from above ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf script can report the dso for "addr" and "ip" fields.
This adds the same support for the "brstack" and "brstacksym" fields.
This can be helpful for AutoFDO: we can ignore LBR entries unless the
source and target address are both in the target module we are about to
build.
I built a small test akin to "while(1) { do_nothing(); }" where the
do_nothing function is loaded from a dso:
$ cat burncpu.cpp
#include <dlfcn.h>
int main() {
void* handle = dlopen("./dso.so", RTLD_LAZY);
if (!handle) return -1;
typedef void (*fp)();
fp do_nothing = (fp) dlsym(handle, "do_nothing");
while(1) {
do_nothing();
}
}
$ cat dso.cpp
extern "C" void do_nothing() {}
$ cat build.sh
#!/bin/bash
g++ -shared dso.cpp -o dso.so
g++ burncpu.cpp -o burncpu -ldl
I sampled the execution with perf record -b. Using the new perf script
functionality I can easily find cases where there was a transition from one
dso to another:
$ perf record -a -b -- sleep 5
[ perf record: Woken up 55 times to write data ]
[ perf record: Captured and wrote 18.815 MB perf.data (43593 samples) ]
$ perf script -F brstack,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
0x7f967139b6aa(/tmp/burncpu/dso.so)/0x4006b1(/tmp/burncpu/exe)/P/-/-/0
$ perf script -F brstacksym,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
do_nothing+0x5(/tmp/burncpu/dso.so)/main+0x44(/tmp/burncpu/exe)/P/-/-/0
Signed-off-by: Mark Santaniello <marksan@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170619163825.2012979-1-marksan@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'if' keyword is a define that expands to complex code when
CONFIG_PROFILE_ALL_BRANCHES is selected, which causes a 'perf test LLVM'
failure like:
$ ./perf test LLVM
35: LLVM search and compile :
35.1: Basic BPF llvm compile : Ok
35.2: kbuild searching : Ok
35.3: Compile source for BPF prologue generation: FAILED!
35.4: Compile source for BPF relocation : Skip
The only affected test case is bpf-script-test-prologue.c
because it uses kernel headers and has 'if' inside.
This patch undefines 'if' to make it passes perf test.
More detailed analysis from a message in this thread, also by Wang:
The problem is caused by following relocation information:
$ readelf -a ./llvmsubtest3
...
[ 5] _ftrace_branch PROGBITS 0000000000000000 00000260
00000000000000a0 0000000000000000 WA 0 0 4
...
Relocation section '.relfunc=null_lseek file->f_mode offset orig' at
offset 0x490 contains 4 entries:
Offset Info Type Sym. Value Sym. Name
000000000038 000b00000001 unrecognized: 1 0000000000000000 _ftrace_branch
0000000000b0 000b00000001 unrecognized: 1 0000000000000000 _ftrace_branch
000000000128 000b00000001 unrecognized: 1 0000000000000000 _ftrace_branch
0000000001c0 000b00000001 unrecognized: 1 0000000000000000 _ftrace_branch
Relocation section '.rel_ftrace_branch' at offset 0x4d0 contains 8 entries:
Offset Info Type Sym. Value Sym. Name
000000000000 000200000001 unrecognized: 1 0000000000000000 .L__func__.bpf_func__n
000000000008 000100000001 unrecognized: 1 0000000000000015 .L.str
000000000028 000200000001 unrecognized: 1 0000000000000000 .L__func__.bpf_func__n
000000000030 000100000001 unrecognized: 1 0000000000000015 .L.str
000000000050 000200000001 unrecognized: 1 0000000000000000 .L__func__.bpf_func__n
000000000058 000100000001 unrecognized: 1 0000000000000015 .L.str
000000000078 000200000001 unrecognized: 1 0000000000000000 .L__func__.bpf_func__n
000000000080 000100000001 unrecognized: 1 0000000000000015 .L.str
...
So I think the failure is because you enabled CONFIG_PROFILE_ALL_BRANCHES.
I can reproduce your buggy result by selecting
CONFIG_PROFILE_ALL_BRANCHES in my kbuild:
$ ./perf test LLVM
35: LLVM search and compile :
35.1: Basic BPF llvm compile : Ok
35.2: kbuild searching : Ok
35.3: Compile source for BPF prologue generation: FAILED!
35.4: Compile source for BPF relocation : Skip
Simply undef CONFIG_PROFILE_ALL_BRANCHES in clang opts not working
because it is introduced by "#include <uapi/linux/fs.h>", which override
cmdline options. So I think the best way is to undefine 'if' inside BPF
script.
Reported-and-Tested-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/20170620183203.2517-1-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The code mistakenly prints the local perf results for the remote test
so the script reports identical results for both directions. Fix this
by ensuring we print the remote result.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Fixes: a9c59ef774 ("ntb_test: Add a selftest script for the NTB subsystem")
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
