As stated in tests/llvm-src-base.c, the name of the bpf function should
be "bpf_func__SyS_epoll_pwait" but this clang test fails as it tries to
lookup "bpf_func__SyS_epoll_wait".
Before applying patch:
55: builtin clang support :
55.1: builtin clang compile C source to IR : FAILED!
55.2: builtin clang compile C source to ELF object : Skip
After applying patch:
55: builtin clang support :
55.1: builtin clang compile C source to IR : Ok
55.2: builtin clang compile C source to ELF object : Ok
Signed-off-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Fixes: e67d52d411 ("perf clang: Update test case to use real BPF script")
Link: http://lkml.kernel.org/r/20180404180419.19056-3-sandipan@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The clang API calls used by perf have changed in recent releases and
builds succeed with libclang-3.9 only. This introduces compatibility
with libclang-4.0 and above.
Without this patch, we will see the following compilation errors with
libclang-4.0+:
util/c++/clang.cpp: In function ‘clang::CompilerInvocation* perf::createCompilerInvocation(llvm::opt::ArgStringList, llvm::StringRef&, clang::DiagnosticsEngine&)’:
util/c++/clang.cpp:62:33: error: ‘IK_C’ was not declared in this scope
Opts.Inputs.emplace_back(Path, IK_C);
^~~~
util/c++/clang.cpp: In function ‘std::unique_ptr<llvm::Module> perf::getModuleFromSource(llvm::opt::ArgStringList, llvm::StringRef, llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem>)’:
util/c++/clang.cpp:75:26: error: no matching function for call to ‘clang::CompilerInstance::setInvocation(clang::CompilerInvocation*)’
Clang.setInvocation(&*CI);
^
In file included from util/c++/clang.cpp:14:0:
/usr/include/clang/Frontend/CompilerInstance.h:231:8: note: candidate: void clang::CompilerInstance::setInvocation(std::shared_ptr<clang::CompilerInvocation>)
void setInvocation(std::shared_ptr<CompilerInvocation> Value);
^~~~~~~~~~~~~
Committer testing:
Tested on Fedora 27 after installing the clang-devel and llvm-devel
packages, versions:
# rpm -qa | egrep llvm\|clang
llvm-5.0.1-6.fc27.x86_64
clang-libs-5.0.1-5.fc27.x86_64
clang-5.0.1-5.fc27.x86_64
clang-tools-extra-5.0.1-5.fc27.x86_64
llvm-libs-5.0.1-6.fc27.x86_64
llvm-devel-5.0.1-6.fc27.x86_64
clang-devel-5.0.1-5.fc27.x86_64
#
Make sure you don't have some older version lying around in /usr/local,
etc, then:
$ make LIBCLANGLLVM=1 -C tools/perf install-bin
And in the end perf will be linked agains these libraries:
# ldd ~/bin/perf | egrep -i llvm\|clang
libclangAST.so.5 => /lib64/libclangAST.so.5 (0x00007f8bb2eb4000)
libclangBasic.so.5 => /lib64/libclangBasic.so.5 (0x00007f8bb29e3000)
libclangCodeGen.so.5 => /lib64/libclangCodeGen.so.5 (0x00007f8bb23f7000)
libclangDriver.so.5 => /lib64/libclangDriver.so.5 (0x00007f8bb2060000)
libclangFrontend.so.5 => /lib64/libclangFrontend.so.5 (0x00007f8bb1d06000)
libclangLex.so.5 => /lib64/libclangLex.so.5 (0x00007f8bb1a3e000)
libclangTooling.so.5 => /lib64/libclangTooling.so.5 (0x00007f8bb17d4000)
libclangEdit.so.5 => /lib64/libclangEdit.so.5 (0x00007f8bb15c5000)
libclangSema.so.5 => /lib64/libclangSema.so.5 (0x00007f8bb0cc9000)
libclangAnalysis.so.5 => /lib64/libclangAnalysis.so.5 (0x00007f8bb0a23000)
libclangParse.so.5 => /lib64/libclangParse.so.5 (0x00007f8bb0725000)
libclangSerialization.so.5 => /lib64/libclangSerialization.so.5 (0x00007f8bb039a000)
libLLVM-5.0.so => /lib64/libLLVM-5.0.so (0x00007f8bace98000)
libclangASTMatchers.so.5 => /lib64/../lib64/libclangASTMatchers.so.5 (0x00007f8bab735000)
libclangFormat.so.5 => /lib64/../lib64/libclangFormat.so.5 (0x00007f8bab4b2000)
libclangRewrite.so.5 => /lib64/../lib64/libclangRewrite.so.5 (0x00007f8bab2a1000)
libclangToolingCore.so.5 => /lib64/../lib64/libclangToolingCore.so.5 (0x00007f8bab08e000)
#
Signed-off-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Fixes: 00b86691c7 ("perf clang: Add builtin clang support ant test case")
Link: http://lkml.kernel.org/r/20180404180419.19056-2-sandipan@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The per-browser screen refresh routine (ui_browser->refresh()) should
return the first row that should be cleaned after the rows just printed,
in case not all rows available on the screen gets filled.
When moving the extra title lines logic from the hists browser to the
generic ui_browser class, one piece of that logic remained in the hists
browser and then when going back from the annotate browser to the hists
browser in a case where fewer lines were displayed in the hists browser,
for instance when filtering the entries per substring, one line of the
annotate browser would remain on the screen, fix that.
Example of the screen artifact:
================================================================================
Samples: 73K of event 'cycles:ppp', 4000 Hz, Event count (approx.): 45172901394
Overhead Shared O Symbol
0.30% [kernel] [k] __indirect_thunk_start
0.09% [kernel] [k] __x86_indirect_thunk_r10
│ lfence
================================================================================
Here from 'perf top' the view was zoomed with '/thunk' to functions
having that substring, then the first was annotated and from the
annotate browser ESC was pressed, then the first lines were overwritten,
but the 'lfence' line remained due to the off by one bug fixed in this
cset.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: ef9ff6017e ("perf ui browser: Move the extra title lines from the hists browser")
Link: https://lkml.kernel.org/n/tip-odryfso74eaarm0z3e4v9owx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now that we can have extra title lines we should use ui_browser->rows
and not ->height when drawing lines, as it will use ui_browser__gotorc()
and that will take the extra title lines into account, which was causing
an off by one at the end of the vertical line drawn by
__ui_browser__vline(), fix it.
The visual effect was that the last line, with status messages, was
being overwritten by the vertical line, looking like:
Press 'h' for help on│key bindings
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: ef9ff6017e ("perf ui browser: Move the extra title lines from the hists browser")
Link: https://lkml.kernel.org/n/tip-08y1ln3xjn76zvizz1i1dsvn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To match what is shown in the main 'perf report/top' title lines, i.e.
if a group is being shown, either a real group (recorded with "-e
'{a,b,c}') or a forced group (using 'perf report --group' for a
perf.data file recorded without {}) we will show multiple columns,
one per event, but we were failing to show the group details, so, for:
# perf report --header-only | grep cmdline
# cmdline : /home/acme/bin/perf record -e {cycles,instructions,cache-misses}
# perf report --group
The first line was showing just "cycles", now it shows the correct line,
which is:
Samples: 578 of events 'anon group { cycles, instructions, cache-misses }', 4000 Hz, Event count (approx.): 487421794
syscall_return_via_sysret /lib/modules/4.16.0-rc7/build/vmlinux
0.22 2.97 0.00 │ ↓ jmp 6c
│ mov %cr3,%rdi
1.33 10.89 4.00 │ ↓ jmp 62
│ mov %rdi,%rax
<SNIP>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 6920e2854e ("perf annotate browser: Show extra title line with event information")
Link: https://lkml.kernel.org/n/tip-i41tqh17c2dabnyzjh99r1oz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
- Show only failing syscalls with 'perf trace --failure' (Arnaldo Carvalho de Melo)
e.g: See what 'openat' syscalls are failing:
# perf trace --failure -e openat
762.323 ( 0.007 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video2) = -1 ENOENT No such file or directory
<SNIP N /dev/videoN open attempts... sigh, where is that improvised camera lid?!? >
790.228 ( 0.008 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video63) = -1 ENOENT No such file or directory
^C#
- Show information about the event (freq, nr_samples, total period/nr_events) in
the annotate --tui and --stdio2 'perf annotate' output, similar to the
first line in the 'perf report --tui', but just for the samples for a
the annotated symbol (Arnaldo Carvalho de Melo)
- Introduce 'perf version --build-options' to show what features were
linked, aliased as well as a shorter 'perf -vv' (Jin Yao)
- Add a "dso_size" sort order (Kim Phillips)
- Remove redundant ')' in the tracepoint output in 'perf trace' (Changbin Du)
- Synchronize x86's cpufeatures.h, no effect on toolss (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This will be useful for the annotate browser as well, that wants to have
extra title lines, i.e. the current ui_browser unconditionally reserves
the first line for a browser title and the last one for status messages.
But some browsers, like the buckets one (hists browser) needs extra
lines to show headers, allowing it to be shown or not, press 'H' in
'perf top' or 'perf report' to see this feature.
So move that logic to the core ui_browser used by the hists_browser
('perf top' and 'perf report' main interface) so that it can be used by
the annotate browser too.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196935
Link: https://lkml.kernel.org/n/tip-r38xm3ut37ulbg1o5tn5iise@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pul removal of obsolete architecture ports from Arnd Bergmann:
"This removes the entire architecture code for blackfin, cris, frv,
m32r, metag, mn10300, score, and tile, including the associated device
drivers.
I have been working with the (former) maintainers for each one to
ensure that my interpretation was right and the code is definitely
unused in mainline kernels. Many had fond memories of working on the
respective ports to start with and getting them included in upstream,
but also saw no point in keeping the port alive without any users.
In the end, it seems that while the eight architectures are extremely
different, they all suffered the same fate: There was one company in
charge of an SoC line, a CPU microarchitecture and a software
ecosystem, which was more costly than licensing newer off-the-shelf
CPU cores from a third party (typically ARM, MIPS, or RISC-V). It
seems that all the SoC product lines are still around, but have not
used the custom CPU architectures for several years at this point. In
contrast, CPU instruction sets that remain popular and have actively
maintained kernel ports tend to all be used across multiple licensees.
[ See the new nds32 port merged in the previous commit for the next
generation of "one company in charge of an SoC line, a CPU
microarchitecture and a software ecosystem" - Linus ]
The removal came out of a discussion that is now documented at
https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
marking any ports as deprecated but remove them all at once after I
made sure that they are all unused. Some architectures (notably tile,
mn10300, and blackfin) are still being shipped in products with old
kernels, but those products will never be updated to newer kernel
releases.
After this series, we still have a few architectures without mainline
gcc support:
- unicore32 and hexagon both have very outdated gcc releases, but the
maintainers promised to work on providing something newer. At least
in case of hexagon, this will only be llvm, not gcc.
- openrisc, risc-v and nds32 are still in the process of finishing
their support or getting it added to mainline gcc in the first
place. They all have patched gcc-7.3 ports that work to some
degree, but complete upstream support won't happen before gcc-8.1.
Csky posted their first kernel patch set last week, their situation
will be similar
[ Palmer Dabbelt points out that RISC-V support is in mainline gcc
since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]"
This really says it all:
2498 files changed, 95 insertions(+), 467668 deletions(-)
* tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits)
MAINTAINERS: UNICORE32: Change email account
staging: iio: remove iio-trig-bfin-timer driver
tty: hvc: remove tile driver
tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers
serial: remove tile uart driver
serial: remove m32r_sio driver
serial: remove blackfin drivers
serial: remove cris/etrax uart drivers
usb: Remove Blackfin references in USB support
usb: isp1362: remove blackfin arch glue
usb: musb: remove blackfin port
usb: host: remove tilegx platform glue
pwm: remove pwm-bfin driver
i2c: remove bfin-twi driver
spi: remove blackfin related host drivers
watchdog: remove bfin_wdt driver
can: remove bfin_can driver
mmc: remove bfin_sdh driver
input: misc: remove blackfin rotary driver
input: keyboard: remove bf54x driver
...
We keep having bug reports that when users build perf on their own, but
they don't install some needed libraries such as libelf,
libbfd/libibery.
The perf can build, but it is missing important functionality.
This patch provides a new option '-vv' for perf which will print the
compiled-in status of libraries.
The 'perf -vv' is mapped to 'perf version --build-options'.
For example:
$ ./perf -vv
perf version 4.13.rc5.g6727c5
dwarf: [ on ] # HAVE_DWARF_SUPPORT
dwarf_getlocations: [ on ] # HAVE_DWARF_GETLOCATIONS_SUPPORT
glibc: [ on ] # HAVE_GLIBC_SUPPORT
gtk2: [ on ] # HAVE_GTK2_SUPPORT
libaudit: [ OFF ] # HAVE_LIBAUDIT_SUPPORT
libbfd: [ on ] # HAVE_LIBBFD_SUPPORT
libelf: [ on ] # HAVE_LIBELF_SUPPORT
libnuma: [ on ] # HAVE_LIBNUMA_SUPPORT
numa_num_possible_cpus: [ on ] # HAVE_LIBNUMA_SUPPORT
libperl: [ on ] # HAVE_LIBPERL_SUPPORT
libpython: [ on ] # HAVE_LIBPYTHON_SUPPORT
libslang: [ on ] # HAVE_SLANG_SUPPORT
libcrypto: [ on ] # HAVE_LIBCRYPTO_SUPPORT
libunwind: [ on ] # HAVE_LIBUNWIND_SUPPORT
libdw-dwarf-unwind: [ on ] # HAVE_DWARF_SUPPORT
zlib: [ on ] # HAVE_ZLIB_SUPPORT
lzma: [ on ] # HAVE_LZMA_SUPPORT
get_cpuid: [ on ] # HAVE_AUXTRACE_SUPPORT
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
v3:
One bug is found in v2. It didn't process the option like '-vabc'
correctly. Fix this bug.
v2:
Use a global variable version_verbose to record the number of 'v'.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1522402036-22915-6-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch checks the values passed by CFLAGS (-DHAVE_XXX) and then
print the status of libraries.
For example, if HAVE_DWARF_SUPPORT is defined, that means the library
"dwarf" is compiled-in. The patch will print the status "on" for this
library otherwise it print the status "OFF".
A new option '--build-options' created for 'perf version' supports the
printing of library status.
For example:
$ ./perf version --build-options
or
./perf --version --build-options
or
./perf -v --build-options
perf version 4.13.rc5.g6727c5
dwarf: [ on ] # HAVE_DWARF_SUPPORT
dwarf_getlocations: [ on ] # HAVE_DWARF_GETLOCATIONS_SUPPORT
glibc: [ on ] # HAVE_GLIBC_SUPPORT
gtk2: [ on ] # HAVE_GTK2_SUPPORT
libaudit: [ OFF ] # HAVE_LIBAUDIT_SUPPORT
libbfd: [ on ] # HAVE_LIBBFD_SUPPORT
libelf: [ on ] # HAVE_LIBELF_SUPPORT
libnuma: [ on ] # HAVE_LIBNUMA_SUPPORT
numa_num_possible_cpus: [ on ] # HAVE_LIBNUMA_SUPPORT
libperl: [ on ] # HAVE_LIBPERL_SUPPORT
libpython: [ on ] # HAVE_LIBPYTHON_SUPPORT
libslang: [ on ] # HAVE_SLANG_SUPPORT
libcrypto: [ on ] # HAVE_LIBCRYPTO_SUPPORT
libunwind: [ on ] # HAVE_LIBUNWIND_SUPPORT
libdw-dwarf-unwind: [ on ] # HAVE_DWARF_SUPPORT
zlib: [ on ] # HAVE_ZLIB_SUPPORT
lzma: [ on ] # HAVE_LZMA_SUPPORT
get_cpuid: [ on ] # HAVE_AUXTRACE_SUPPORT
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
v4:
1. Also print the macro name. That would make it easier
to grep around in the source looking for where code
related a particular features is located.
2. Update since HAVE_DWARF_GETLOCATIONS is renamed to
HAVE_DWARF_GETLOCATIONS_SUPPORT
v3:
Remove following unnecessary help message.
1. [ on ]: library is compiled-in
[ OFF ]: library is disabled in make configuration
OR library is not installed in build environment
2. Create '--build-options' option.
3. Use standard option parsing API 'parse_options'.
v2:
1. Use IS_BUILTIN macro to replace #ifdef/#endif block.
2. Print color for on/OFF.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1522402036-22915-5-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For most of libraries, in perf.config, they are recorded with -DHAVE_XXX in
CFLAGS according to if the libraries are compiled-in. Then C code then will
know if the library is compiled-in or not.
While for glibc, no -DHAVE_GLIBC_SUPPORT exists.
For python and perl libraries, only -DNO_PYTHON and -DNO_LIBPERL exist.
To make the code more consistent, the patch creates -DHAVE_LIBPYTHON_SUPPORT
and -DHAVE_LIBPERL_SUPPORT if the python and perl libraries are compiled-in.
Since the existing flags -DNO_PYTHON and -DNO_LIBPERL are being used in many
places in C code, this patch doesn't remove them. In a follow-up patch, we will
recontruct the C code and then use HAVE_XXX instead.
v3:
Move 'CFLAGS += -DHAVE_LIBPYTHON_SUPPORT' and 'CFLAGS +=
-DHAVE_LIBPERL_SUPPORT' to other places to avoid duplicated feature checking.
v2:
Create -DHAVE_GLIBC_SUPPORT, -DHAVE_LIBPYTHON_SUPPORT and
-DHAVE_LIBPERL_SUPPORT.
Signed-off-by: Jin Yao <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: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1522402036-22915-3-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
These types of jumps were confusing the annotate browser:
entry_SYSCALL_64 /lib/modules/4.16.0-rc5-00086-gdf09348f78dc/build/vmlinux
entry_SYSCALL_64 /lib/modules/4.16.0-rc5-00086-gdf09348f78dc/build/vmlinux
Percent│ffffffff81a00020: swapgs
<SNIP>
│ffffffff81a00128: ↓ jae ffffffff81a00139 <syscall_return_via_sysret+0x53>
<SNIP>
│ffffffff81a00155: → jmpq *0x825d2d(%rip) # ffffffff82225e88 <pv_cpu_ops+0xe8>
I.e. the syscall_return_via_sysret function is actually "inside" the
entry_SYSCALL_64 function, and the offsets in jumps like these (+0x53)
are relative to syscall_return_via_sysret, not to syscall_return_via_sysret.
Or this may be some artifact in how the assembler marks the start and
end of a function and how this ends up in the ELF symtab for vmlinux,
i.e. syscall_return_via_sysret() isn't "inside" entry_SYSCALL_64, but
just right after it.
From readelf -sw vmlinux:
80267: ffffffff81a00020 315 NOTYPE GLOBAL DEFAULT 1 entry_SYSCALL_64
316: ffffffff81a000e6 0 NOTYPE LOCAL DEFAULT 1 syscall_return_via_sysret
0xffffffff81a00020 + 315 > 0xffffffff81a000e6
So instead of looking for offsets after that last '+' sign, calculate
offsets for jump target addresses that are inside the function being
disassembled from the absolute address, 0xffffffff81a00139 in this case,
subtracting from it the objdump address for the start of the function
being disassembled, entry_SYSCALL_64() in this case.
So, before this patch:
entry_SYSCALL_64 /lib/modules/4.16.0-rc5-00086-gdf09348f78dc/build/vmlinux
Percent│ pop %r10
│ pop %r9
│ pop %r8
│ pop %rax
│ pop %rsi
│ pop %rdx
│ pop %rsi
│ mov %rsp,%rdi
│ mov %gs:0x5004,%rsp
│ pushq 0x28(%rdi)
│ pushq (%rdi)
│ push %rax
│ ↑ jmp 6c
│ mov %cr3,%rdi
│ ↑ jmp 62
│ mov %rdi,%rax
│ and $0x7ff,%rdi
│ bt %rdi,%gs:0x2219a
│ ↑ jae 53
│ btr %rdi,%gs:0x2219a
│ mov %rax,%rdi
│ ↑ jmp 5b
After:
entry_SYSCALL_64 /lib/modules/4.16.0-rc5-00086-gdf09348f78dc/build/vmlinux
0.65 │ → jne swapgs_restore_regs_and_return_to_usermode
│ pop %r10
│ pop %r9
│ pop %r8
│ pop %rax
│ pop %rsi
│ pop %rdx
│ pop %rsi
│ mov %rsp,%rdi
│ mov %gs:0x5004,%rsp
│ pushq 0x28(%rdi)
│ pushq (%rdi)
│ push %rax
│ ↓ jmp 132
│ mov %cr3,%rdi
│ ┌──jmp 128
│ │ mov %rdi,%rax
│ │ and $0x7ff,%rdi
│ │ bt %rdi,%gs:0x2219a
│ │↓ jae 119
│ │ btr %rdi,%gs:0x2219a
│ │ mov %rax,%rdi
│ │↓ jmp 121
│119:│ mov %rax,%rdi
│ │ bts $0x3f,%rdi
│121:│ or $0x800,%rdi
│128:└─→or $0x1000,%rdi
│ mov %rdi,%cr3
│132: pop %rax
│ pop %rdi
│ pop %rsp
│ → jmpq *0x825d2d(%rip) # ffffffff82225e88 <pv_cpu_ops+0xe8>
With those at least navigating to the right destination, an improvement
for these cases seems to be to be to somehow mark those inner functions,
which in this case could be:
entry_SYSCALL_64 /lib/modules/4.16.0-rc5-00086-gdf09348f78dc/build/vmlinux
│syscall_return_via_sysret:
│ pop %r15
│ pop %r14
│ pop %r13
│ pop %r12
│ pop %rbp
│ pop %rbx
│ pop %rsi
│ pop %r10
│ pop %r9
│ pop %r8
│ pop %rax
│ pop %rsi
│ pop %rdx
│ pop %rsi
│ mov %rsp,%rdi
│ mov %gs:0x5004,%rsp
│ pushq 0x28(%rdi)
│ pushq (%rdi)
│ push %rax
│ ↓ jmp 132
│ mov %cr3,%rdi
│ ┌──jmp 128
│ │ mov %rdi,%rax
│ │ and $0x7ff,%rdi
│ │ bt %rdi,%gs:0x2219a
│ │↓ jae 119
│ │ btr %rdi,%gs:0x2219a
│ │ mov %rax,%rdi
│ │↓ jmp 121
│119:│ mov %rax,%rdi
│ │ bts $0x3f,%rdi
│121:│ or $0x800,%rdi
│128:└─→or $0x1000,%rdi
│ mov %rdi,%cr3
│132: pop %rax
│ pop %rdi
│ pop %rsp
│ → jmpq *0x825d2d(%rip) # ffffffff82225e88 <pv_cpu_ops+0xe8>
This all gets much better viewed if one uses 'perf report --ignore-vmlinux'
forcing the usage of /proc/kcore + /proc/kallsyms, when the above
actually gets down to:
# perf report --ignore-vmlinux
## do '/64', will show the function names containing '64',
## navigate to /entry_SYSCALL_64_after_hwframe.annotation,
## press 'A' to annotate, then 'P' to print that annotation
## to a file
## From another xterm (or see on screen, this 'P' thing is for
## getting rid of those right side scroll bars/spaces):
# cat /entry_SYSCALL_64_after_hwframe.annotation
entry_SYSCALL_64_after_hwframe() /proc/kcore
Event: cycles:ppp
Percent
Disassembly of section load0:
ffffffff9aa00044 <load0>:
11.97 push %rax
4.85 push %rdi
push %rsi
2.59 push %rdx
2.27 push %rcx
0.32 pushq $0xffffffffffffffda
1.29 push %r8
xor %r8d,%r8d
1.62 push %r9
0.65 xor %r9d,%r9d
1.62 push %r10
xor %r10d,%r10d
5.50 push %r11
xor %r11d,%r11d
3.56 push %rbx
xor %ebx,%ebx
4.21 push %rbp
xor %ebp,%ebp
2.59 push %r12
0.97 xor %r12d,%r12d
3.24 push %r13
xor %r13d,%r13d
2.27 push %r14
xor %r14d,%r14d
4.21 push %r15
xor %r15d,%r15d
0.97 mov %rsp,%rdi
5.50 → callq do_syscall_64
14.56 mov 0x58(%rsp),%rcx
7.44 mov 0x80(%rsp),%r11
0.32 cmp %rcx,%r11
→ jne swapgs_restore_regs_and_return_to_usermode
0.32 shl $0x10,%rcx
0.32 sar $0x10,%rcx
3.24 cmp %rcx,%r11
→ jne swapgs_restore_regs_and_return_to_usermode
2.27 cmpq $0x33,0x88(%rsp)
1.29 → jne swapgs_restore_regs_and_return_to_usermode
mov 0x30(%rsp),%r11
8.74 cmp %r11,0x90(%rsp)
→ jne swapgs_restore_regs_and_return_to_usermode
0.32 test $0x10100,%r11
→ jne swapgs_restore_regs_and_return_to_usermode
0.32 cmpq $0x2b,0xa0(%rsp)
0.65 → jne swapgs_restore_regs_and_return_to_usermode
I.e. using kallsyms makes the function start/end be done differently
than using what is in the vmlinux ELF symtab and actually the hits
goes to entry_SYSCALL_64_after_hwframe, which is a GLOBAL() after the
start of entry_SYSCALL_64:
ENTRY(entry_SYSCALL_64)
UNWIND_HINT_EMPTY
<SNIP>
pushq $__USER_CS /* pt_regs->cs */
pushq %rcx /* pt_regs->ip */
GLOBAL(entry_SYSCALL_64_after_hwframe)
pushq %rax /* pt_regs->orig_ax */
PUSH_AND_CLEAR_REGS rax=$-ENOSYS
And it goes and ends at:
cmpq $__USER_DS, SS(%rsp) /* SS must match SYSRET */
jne swapgs_restore_regs_and_return_to_usermode
/*
* We win! This label is here just for ease of understanding
* perf profiles. Nothing jumps here.
*/
syscall_return_via_sysret:
/* rcx and r11 are already restored (see code above) */
UNWIND_HINT_EMPTY
POP_REGS pop_rdi=0 skip_r11rcx=1
So perhaps some people should really just play with '--ignore-vmlinux'
to force /proc/kcore + kallsyms.
One idea is to do both, i.e. have a vmlinux annotation and a
kcore+kallsyms one, when possible, and even show the patched location,
etc.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-r11knxv8voesav31xokjiuo6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For instance:
entry_SYSCALL_64 /lib/modules/4.16.0-rc5-00086-gdf09348f78dc/build/vmlinux
5.50 │ → callq do_syscall_64
14.56 │ mov 0x58(%rsp),%rcx
7.44 │ mov 0x80(%rsp),%r11
0.32 │ cmp %rcx,%r11
│ → jne swapgs_restore_regs_and_return_to_usermode
0.32 │ shl $0x10,%rcx
0.32 │ sar $0x10,%rcx
3.24 │ cmp %rcx,%r11
│ → jne swapgs_restore_regs_and_return_to_usermode
2.27 │ cmpq $0x33,0x88(%rsp)
1.29 │ → jne swapgs_restore_regs_and_return_to_usermode
│ mov 0x30(%rsp),%r11
8.74 │ cmp %r11,0x90(%rsp)
│ → jne swapgs_restore_regs_and_return_to_usermode
0.32 │ test $0x10100,%r11
│ → jne swapgs_restore_regs_and_return_to_usermode
0.32 │ cmpq $0x2b,0xa0(%rsp)
0.65 │ → jne swapgs_restore_regs_and_return_to_usermode
It'll behave just like a "call" instruction, i.e. press enter or right
arrow over one such line and the browser will navigate to the annotated
disassembly of that function, which when exited, via left arrow or esc,
will come back to the calling function.
Now to support jump to an offset on a different function...
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-78o508mqvr8inhj63ddtw7mo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Because they all really check if we can access data structures/visual
constructs where a "jump" instruction targets code in the same function,
i.e. things like:
__pthread_mutex_lock /usr/lib64/libpthread-2.26.so
1.95 │ mov __pthread_force_elision,%ecx
│ ┌──test %ecx,%ecx
0.07 │ ├──je 60
│ │ test $0x300,%esi
│ │↓ jne 60
│ │ or $0x100,%esi
│ │ mov %esi,0x10(%rdi)
│ 42:│ mov %esi,%edx
│ │ lea 0x16(%r8),%rsi
│ │ mov %r8,%rdi
│ │ and $0x80,%edx
│ │ add $0x8,%rsp
│ │→ jmpq __lll_lock_elision
│ │ nop
0.29 │ 60:└─→and $0x80,%esi
0.07 │ mov $0x1,%edi
0.29 │ xor %eax,%eax
2.53 │ lock cmpxchg %edi,(%r8)
And not things like that "jmpq __lll_lock_elision", that instead should behave
like a "call" instruction and "jump" to the disassembly of "___lll_lock_elision".
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-3cwx39u3h66dfw9xjrlt7ca2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Things like this in _cpp_lex_token (gcc's cc1 program):
cpp_named_operator2name@@Base+0xa72
Point to a place that is after the cpp_named_operator2name boundaries,
i.e. in the ELF symbol table for cc1 cpp_named_operator2name is marked
as being 32-bytes long, but it in fact is much larger than that, so we
seem to need a symbols__find() routine that looks for >= current->start
and < next_symbol->start, possibly just for C++ objects?
For now lets just make some progress by marking jumps to outside the
current function as call like.
Actual navigation will come next, with further understanding of how the
symbol searching and disassembly should be done.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-aiys0a0bsgm3e00hbi6fg7yy@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Just like we have in the histograms browser used as the main screen for
'perf top --tui' and 'perf report --tui', to print the current
annotation to a file with a named composed by the symbol name and the
".annotation" suffix.
Here is one example of pressing 'A' on 'perf top' to live annotate a
kernel function and then press 'P' to dump that annotation, the
resulting file:
# cat _raw_spin_lock_irqsave.annotation
_raw_spin_lock_irqsave() /proc/kcore
Event: cycles:ppp
7.14 nop
21.43 push %rbx
7.14 pushfq
pop %rax
nop
mov %rax,%rbx
cli
nop
xor %eax,%eax
mov $0x1,%edx
64.29 lock cmpxchg %edx,(%rdi)
test %eax,%eax
↓ jne 2b
mov %rbx,%rax
pop %rbx
← retq
2b: mov %eax,%esi
→ callq queued_spin_lock_slowpath
mov %rbx,%rax
pop %rbx
← retq
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zzmnrwugb5vtk7bvg0rbx150@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>