kernel/tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c, branch linux-6.2.y

perf tools: Move 'struct perf_sample' to a separate header file to disentangle headers

2022-10-31T14:06:41Z

Some places were including event.h just to get 'struct perf_sample', move it to a separate place so that we speed up a bit the build. Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Add support for emulated ptwrite

2022-05-17T14:55:49Z

ptwrite is an Intel x86 instruction that writes arbitrary values into an Intel PT trace. It is not supported on all hardware, so provide an alternative that makes use of TNT packets to convey the payload data. TNT packets encode Taken/Not-taken conditional branch information, so taking branches based on the payload value will encode the value into the TNT packet. Refer to the changes to the documentation file perf-intel-pt.txt in this patch for an example. Signed-off-by: Adrian Hunter Cc: Jiri Olsa Link: https://lore.kernel.org/r/20220509152400.376613-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Use __BYTE_ORDER__

2021-11-07T15:27:38Z

Switch from the libc-defined __BYTE_ORDER to the compiler-defined __BYTE_ORDER__ in order to make endianness detection more robust, like it was done for libbpf. Signed-off-by: Ilya Leoshkevich Suggested-by: Arnaldo Carvalho de Melo Cc: Heiko Carstens Cc: Thomas Richter Cc: Vasily Gorbik Link: https://lore.kernel.org/r/20211104132311.984703-1-iii@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo

tools/perf: Convert to insn_decode()

2021-03-15T11:41:26Z

Simplify code, no functional changes. Signed-off-by: Borislav Petkov Cc: Arnaldo Carvalho de Melo Link: https://lkml.kernel.org/r/20210304174237.31945-20-bp@alien8.de

perf intel_pt: Add vmlaunch and vmresume as branches

2021-02-18T19:13:30Z

In preparation to support Intel PT decoding of virtual machine traces, add vmlaunch and vmresume as branch instructions. Note, sample flags will show "VMentry" even if the VM-Entry fails. Signed-off-by: Adrian Hunter Acked-by: Andi Kleen Cc: Alexander Shishkin Cc: Jiri Olsa Link: https://lore.kernel.org/r/20210218095801.19576-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf intel-pt: Use shared x86 insn decoder

2019-09-01T01:27:52Z

Now that there's a common version of the decoder for all tools, use it instead of the local copy. Also use perf's check-headers.sh script to diff the decoder files to make sure they remain in sync with the kernel version. Objtool has a similar check. Committer notes: Had to keep this all pointing explicitely to x86 headers/files, i.e. instead of asm/isnn.h we had to use ../include/asm/insn.h when the files were in differemt dirs, or just replace "" with "foo.h". This way we continue to be able to process perf.data files with Intel PT traces in distros other than x86. Also fixed up the awk script paths to use $(srcdir)/tools/arch instead or relative directories so that we keep detached tarballs (make help | grep perf) working. For now the include lines in these headers are being ignored so as not to flag false reports of kernel/tools out of sync. Signed-off-by: Josh Poimboeuf Reviewed-by: Masami Hiramatsu Acked-by: Peter Zijlstra (Intel) Cc: Adrian Hunter Cc: Jiri Olsa Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/8a37e615d2880f039505d693d1e068a009358a2b.1567118001.git.jpoimboe@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288

2019-06-05T15:36:37Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 263 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de Signed-off-by: Greg Kroah-Hartman

perf script: Fix LBR skid dump problems in brstackinsn

2018-12-28T19:33:02Z

This is a fix for another instance of the skid problem Milian recently found [1] The LBRs don't freeze at the exact same time as the PMI is triggered. The perf script brstackinsn code that dumps LBR assembler assumes that the last branch in the LBR leads to the sample point. But with skid it's possible that the CPU executes one or more branches before the sample, but which do not appear in the LBR. What happens then is either that the sample point is before the last LBR branch. In this case the dumper sees a negative length and ignores it. Or it the sample point is long after the last branch. Then the dumper sees a very long block and dumps it upto its block limit (16k bytes), which is noise in the output. On typical sample session this can happen regularly. This patch tries to detect and handle the situation. On the last block that is dumped by the LBR dumper we always stop on the first branch. If the block length is negative just scan forward to the first branch. Otherwise scan until a branch is found. The PT decoder already has a function that uses the instruction decoder to detect branches, so we can just reuse it here. Then when a terminating branch is found print an indication and stop dumping. This might miss a few instructions, but at least shows no runaway blocks. Signed-off-by: Andi Kleen Acked-by: Adrian Hunter Cc: Jiri Olsa Cc: Milian Wolff Link: http://lkml.kernel.org/r/20181120050617.4119-1-andi@firstfloor.org [ Resolved conflict with dd2e18e9ac20 ("perf tools: Support 'srccode' output") ] Signed-off-by: Arnaldo Carvalho de Melo

Merge tag 'perf-core-for-mingo-4.12-20170316' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

2017-03-16T16:29:23Z

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: New features: - Add 'brstackinsn' field in 'perf script' to reuse the x86 instruction decoder used in the Intel PT code to study hot paths to samples (Andi Kleen) Kernel changes: - Default UPROBES_EVENTS to Y (Alexei Starovoitov) - Fix check for kretprobe offset within function entry (Naveen N. Rao) Infrastructure changes: - Introduce util func is_sdt_event() (Ravi Bangoria) - Make perf_event__synthesize_mmap_events() scale on older kernels where reading /proc/pid/maps is way slower than reading /proc/pid/task/pid/maps (Stephane Eranian) Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Ingo Molnar

perf script: Add 'brstackinsn' for branch stacks

2017-03-16T12:24:35Z

Implement printing instruction sequences as hex dump for branch stacks. This relies on the x86 instruction decoder used by the PT decoder to find the lengths of instructions to dump them individually. This is good enough for pattern matching. This allows to study hot paths for individual samples, together with branch misprediction and cycle count / IPC information if available (on Skylake systems). % perf record -b ... % perf script -F brstackinsn ... read_hpet+67: ffffffff9905b843 insn: 74 ea # PRED ffffffff9905b82f insn: 85 c9 ffffffff9905b831 insn: 74 12 ffffffff9905b833 insn: f3 90 ffffffff9905b835 insn: 48 8b 0f ffffffff9905b838 insn: 48 89 ca ffffffff9905b83b insn: 48 c1 ea 20 ffffffff9905b83f insn: 39 f2 ffffffff9905b841 insn: 89 d0 ffffffff9905b843 insn: 74 ea # PRED Only works when no special branch filters are specified. Occasionally the path does not reach up to the sample IP, as the LBRs may be frozen before executing a final jump. In this case we print a special message. The instruction dumper piggy backs on the existing infrastructure from the IP PT decoder. An earlier iteration of this patch relied on a disassembler, but this version only uses the existing instruction decoder. Committer note: Added hint about how to get suitable perf.data files for use with '-F brstackinsm': $ perf record usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.018 MB perf.data (8 samples) ] $ $ perf script -F brstackinsn Display of branch stack assembler requested, but non all-branch filter set Hint: run 'perf record -b ...' $ Signed-off-by: Andi Kleen Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Michael Ellerman Link: http://lkml.kernel.org/r/20170223234634.583-1-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo