kernel/tools/perf/util/annotate.h, branch linux-4.15.y

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

perf annotate: Store the sample period in each histogram bucket

2017-07-21T15:02:38Z

We'll use it soon, when fixing --show-total-period. Signed-off-by: Taeung Song Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/1500500215-16646-1-git-send-email-treeze.taeung@gmail.com [ split from a larger patch, do the math in __symbol__inc_addr_samples() ] Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Pass perf_sample to symbolinc_addr_samples()

2017-07-21T11:23:50Z

To pave the way to use perf_sample fields in the annotate code, storing sample->period in sym_hist->addr->period and its sum in sym_hist->period. Signed-off-by: Taeung Song Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/1500500215-16646-1-git-send-email-treeze.taeung@gmail.com [ split and adjusted from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Rename 'sum' to 'nr_samples' in struct sym_hist

2017-07-21T11:23:49Z

To make it more clear that it is the sum of all the nr_samples fields in the addr[] entries, i.e.: sym_hist->nr_samples = sum(sym_hist->addr[0 .. symbol__size(sym)]->nr_samples) Committer notes: Taeung had renamed it to total_samples, but using nr_samples, as in the added explanation above, looks clearer and establishes the direct connection, making clear it is about the _number_ of samples. Signed-off-by: Taeung Song Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/1500500211-16599-1-git-send-email-treeze.taeung@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Introduce struct sym_hist_entry

2017-07-21T11:23:38Z

struct sym_hist has addr[] but it should have not only number of samples but also the sample period. So use new struct symhist_entry to pave the way to have that. Committer notes: This initial patch will only introduce the struct sym_hist_entry and use only the nr_samples member, which makes the code clearer and paves the way to save the period as well. Signed-off-by: Taeung Song Suggested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/1500500205-16553-1-git-send-email-treeze.taeung@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Implement visual marker for macro fusion

2017-07-19T02:13:49Z

For marking fused instructions clearly this patch adds a line before the first instruction of pair and joins it with the arrow of the jump to its target. For example, when "je" is selected in annotate view, the line before cmpl is displayed and joins the arrow of "je". │ ┌──cmpl $0x0,argp_program_version_hook 81.93 │ ├──je 20 │ │ lock cmpxchg %esi,0x38a9a4(%rip) │ │↓ jne 29 │ │↓ jmp 43 11.47 │20:└─→cmpxch %esi,0x38a999(%rip) That means the cmpl+je is a fused instruction pair and they should be considered together. Changelog: v3: Use Arnaldo's fix to improve the arrow origin rendering. To get the evsel->evlist->env->cpuid, save the evsel in annotate_browser. v2: new function "ins__is_fused" to check if the instructions are fused. Signed-off-by: Yao Jin Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1499403995-19857-3-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Check for fused instructions

2017-07-19T02:11:25Z

Macro fusion merges two instructions to a single micro-op. Intel core platform performs this hardware optimization under limited circumstances. For example, CMP + JCC can be "fused" and executed /retired together. While with sampling this can result in the sample sometimes being on the JCC and sometimes on the CMP. So for the fused instruction pair, they could be considered together. On Nehalem, fused instruction pairs: cmp/test + jcc. On other new CPU: cmp/test/add/sub/and/inc/dec + jcc. This patch adds an x86-specific function which checks if 2 instructions are in a "fused" pair. For non-x86 arch, the function is just NULL. Changelog: v4: Move the CPU model checking to symbol__disassemble and save the CPU family/model in arch structure. It avoids checking every time when jump arrow printed. v3: Add checking for Nehalem (CMP, TEST). For other newer Intel CPUs just check it by default (CMP, TEST, ADD, SUB, AND, INC, DEC). v2: Remove the original weak function. Arnaldo points out that doing it as a weak function that will be overridden by the host arch doesn't work. So now it's implemented as an arch-specific function. Committer fix: Do not access evsel->evlist->env->cpuid, ->env can be null, introduce perf_evsel__env_cpuid(), just like perf_evsel__env_arch(), also used in this function call. The original patch was segfaulting 'perf top' + annotation. But this essentially disables this fused instructions augmentation in 'perf top', the right thing is to get the cpuid from the running kernel, left for a later patch tho. Signed-off-by: Yao Jin Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1499403995-19857-2-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Return arch from symbol__disassemble() and save it in browser

2017-06-19T18:27:09Z

In annotate browser, we will add support to check fused instructions. While this is x86-specific feature so we need the annotate browser to know what the arch it runs on. symbol__disassemble() has figured out the arch. This patch just lets the arch return from symbol__disassemble and save the arch in annotate browser. Signed-off-by: Yao Jin Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1497840958-4759-2-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Fix missing number of samples for source_line_samples

2017-04-05T00:08:00Z

The option 'show-total-period' works fine without a option '-l'. But if running 'perf annotate --stdio -l --show-total-period', you can see a problem showing only zero '0' for number of samples. Before: $ perf annotate --stdio -l --show-total-period ... 0 : 400816: push %rbp 0 : 400817: mov %rsp,%rbp 0 : 40081a: mov %edi,-0x24(%rbp) 0 : 40081d: mov %rsi,-0x30(%rbp) 0 : 400821: mov -0x24(%rbp),%eax 0 : 400824: mov -0x30(%rbp),%rdx 0 : 400828: mov (%rdx),%esi 0 : 40082a: mov $0x0,%edx ... The reason is it was missed to set number of samples of source_line_samples, so set it ordinarily. After: $ perf annotate --stdio -l --show-total-period ... 3 : 400816: push %rbp 4 : 400817: mov %rsp,%rbp 0 : 40081a: mov %edi,-0x24(%rbp) 0 : 40081d: mov %rsi,-0x30(%rbp) 1 : 400821: mov -0x24(%rbp),%eax 2 : 400824: mov -0x30(%rbp),%rdx 0 : 400828: mov (%rdx),%esi 1 : 40082a: mov $0x0,%edx ... Signed-off-by: Taeung Song Cc: Jiri Olsa Cc: Martin Liska Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Fixes: 0c4a5bcea460 ("perf annotate: Display total number of samples with --show-total-period") Link: http://lkml.kernel.org/r/1490703125-13643-1-git-send-email-treeze.taeung@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Fix jump target outside of function address range

2016-12-15T19:25:46Z

If jump target is outside of function range, perf is not handling it correctly. Especially when target address is lesser than function start address, target offset will be negative. But, target address declared to be unsigned, converts negative number into 2's complement. See below example. Here target of 'jumpq' instruction at 34cf8 is 34ac0 which is lesser than function start address(34cf0). 34ac0 - 34cf0 = -0x230 = 0xfffffffffffffdd0 Objdump output: 0000000000034cf0 <__sigaction>: __GI___sigaction(): 34cf0: lea -0x20(%rdi),%eax 34cf3: cmp -bashx1,%eax 34cf6: jbe 34d00 <__sigaction+0x10> 34cf8: jmpq 34ac0 <__GI___libc_sigaction> 34cfd: nopl (%rax) 34d00: mov 0x386161(%rip),%rax # 3bae68 <_DYNAMIC+0x2e8> 34d07: movl -bashx16,%fs:(%rax) 34d0e: mov -bashxffffffff,%eax 34d13: retq perf annotate before applying patch: __GI___sigaction /usr/lib64/libc-2.22.so lea -0x20(%rdi),%eax cmp -bashx1,%eax v jbe 10 v jmpq fffffffffffffdd0 nop 10: mov _DYNAMIC+0x2e8,%rax movl -bashx16,%fs:(%rax) mov -bashxffffffff,%eax retq perf annotate after applying patch: __GI___sigaction /usr/lib64/libc-2.22.so lea -0x20(%rdi),%eax cmp -bashx1,%eax v jbe 10 ^ jmpq 34ac0 <__GI___libc_sigaction> nop 10: mov _DYNAMIC+0x2e8,%rax movl -bashx16,%fs:(%rax) mov -bashxffffffff,%eax retq Signed-off-by: Ravi Bangoria Cc: Alexander Shishkin Cc: Chris Riyder Cc: Kim Phillips Cc: Markus Trippelsdorf Cc: Masami Hiramatsu Cc: Naveen N. Rao Cc: Peter Zijlstra Cc: Taeung Song Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1480953407-7605-3-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo