kernel.git/tools/perf/util/hist.c, branch linux-4.18.y

perf hists: Reimplement hists__has_callchains()

2018-06-07T17:42:27Z

There are places where we have only access to struct hists and need to know if any of its hist_entries has callchains, like when drawing headers for the various output modes (stdio, TUI, etc), so, when adding a new hist_entry, check if it has callchains, storing this info for later use by hists__has_callchains(). This reimplementation is necessary because not always a 'struct hists' is allocated together with a 'struct perf evsel', so we can't go from 'hists' to 'perf_event_attr.sample_type & PERF_SAMPLE_CALLCHAIN'. Cc: Adrian Hunter Cc: David Ahern Cc: Jin Yao Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-hg5g7yddjio3ljwyqnnaj5dt@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Save the callchain_size in struct hist_entry

2018-06-07T17:22:53Z

So that we can figure out the real size of the struct and also be able to tell if callchains may be present in this histogram entry. Since we can't always guarantee that from hist_entry->hists we can use hists_to_evsel, to then look at evsel->attr.sample_type for PERF_SAMPLE_CALLCHAIN, like with the 'perf c2c' tool, that uses plain 'struct hists' instances, we need another way of deciding if a specific hist_entry instance has callchains associated with it, i.e. if its hist_entry->callchain[0] has space allocated for. Cc: Adrian Hunter Cc: David Ahern Cc: Jin Yao Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-ptvndealxs1k7myluvu9flnq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Check if a hist_entry has callchains before using them

2018-06-06T15:52:03Z

So far if we use 'perf record -g' this will make symbol_conf.use_callchain 'true' and logic will assume that all events have callchains enabled, but ever since we added the possibility of setting up callchains for some events (e.g.: -e cycles/call-graph=dwarf/) while not for others, we limit usage scenarios by looking at that symbol_conf.use_callchain global boolean, we better look at each event attributes. On the road to that we need to look if a hist_entry has callchains, that is, to go from hist_entry->hists to the evsel that contains it, to then look at evsel->sample_type for PERF_SAMPLE_CALLCHAIN. The next step is to add a symbol_conf.ignore_callchains global, to use in the places where what we really want to know is if callchains should be ignored, even if present. Then -g will mean just to select a callchain mode to be applied to all events not explicitely setting some other callchain mode, i.e. a default callchain mode, and --no-call-graph will set symbol_conf.ignore_callchains with that clear intention. That too will at some point become a per evsel thing, that tools can set for all or just a few of its evsels. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-0sas5cm4dsw2obn75g7ruz69@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Add has_callchain() helper to make code more compact/clear

2018-06-05T13:09:54Z

Its common to have the (evsel->attr.sample_type & PERF_SAMPLE_CALLCHAIN), so add an evsel__has_callchain(evsel) helper. This will actually get more uses as we check that instead of symbol_conf.use_callchain in places where that produces the same result but makes this decision to be more fine grained, per evsel. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-145340oytbthatpfeaq1do18@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: No need to check if the argument to __get() function is NULL

2018-06-04T13:28:50Z

Those functions always check if the argument is NULL before trying to grab a reference count, and also will return the received object, so, to make code more compact, no need to check for NULL. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Krister Johansen Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-i9wycjdxh0fwhryu55lmafks@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Move hists__scnprintf_title() away from the TUI code

2018-04-03T13:23:32Z

The previous patch made this function useful to non-TUI parts of the tools, but left it where the function from what it was carved, so that the patch showed more clearly the process. Now just move it outside the TUI parts so that we can finally use it, even when the TUI code doesn't get built/linked. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Martin Liška Cc: Namhyung Kim Cc: Wang Nan Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196935 Link: https://lkml.kernel.org/n/tip-hqj7hvcr3mu5lvcqp3cssio6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add refcnt into struct mem_info

2018-03-08T14:30:44Z

It's passed along several hists entries in --hierarchy mode, so it's better we keep track of it. The current fail I see is that it gets removed in hierarchy --mem-mode mode, where it's shared in the different hierarchies, but removed from the template hist entry, so the report crashes. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180307155020.32613-6-jolsa@kernel.org [ Rename mem_info__aloc() to mem_info__new(), to fix the typo and use the convention for constructors ] Signed-off-by: Arnaldo Carvalho de Melo

perf report: Fix memory corruption in --branch-history mode --branch-history

2018-02-16T17:55:47Z

Jin Yao reported memory corrupton in perf report with branch info used for stack trace: > Following command lines will cause perf crash. > perf record -j call -g -a > perf report --branch-history > > *** Error in `perf': double free or corruption (!prev): 0x00000000104aa040 *** > ======= Backtrace: ========= > /lib/x86_64-linux-gnu/libc.so.6(+0x77725)[0x7f6b37254725] > /lib/x86_64-linux-gnu/libc.so.6(+0x7ff4a)[0x7f6b3725cf4a] > /lib/x86_64-linux-gnu/libc.so.6(cfree+0x4c)[0x7f6b37260abc] > perf[0x51b914] > perf(hist_entry_iter__add+0x1e5)[0x51f305] > perf[0x43cf01] > perf[0x4fa3bf] > perf[0x4fa923] > perf[0x4fd396] > perf[0x4f9614] > perf(perf_session__process_events+0x89e)[0x4fc38e] > perf(cmd_report+0x15d2)[0x43f202] > perf[0x4a059f] > perf(main+0x631)[0x427b71] > /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0)[0x7f6b371fd830] > perf(_start+0x29)[0x427d89] For the cumulative output, we allocate the he_cache array based on the --max-stack option value and populate it with data from 'callchain_cursor'. The --max-stack option value does not ensure now the limit for number of callchain_cursor nodes, so the cumulative iter code will allocate smaller array than it's actually needed and cause above corruption. I think the --max-stack limit does not apply here anyway, because we add callchain data as normal hist entries, while the --max-stack control the limit of single entry callchain depth. Using the callchain_cursor.nr as he_cache array count to fix this. Also removing struct hist_entry_iter::max_stack, because there's no longer any use for it. We need more fixes to ensure that the branch stack code follows properly the logic of --max-stack, which is not the case at the moment. Original-patch-by: Jin Yao Signed-off-by: Jiri Olsa Reported-by: Jin Yao Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180216123619.GA9945@krava Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'linus' into perf/core, to fix conflicts

2017-11-07T09:30:18Z

Conflicts: tools/perf/arch/arm/annotate/instructions.c tools/perf/arch/arm64/annotate/instructions.c tools/perf/arch/powerpc/annotate/instructions.c tools/perf/arch/s390/annotate/instructions.c tools/perf/arch/x86/tests/intel-cqm.c tools/perf/ui/tui/progress.c tools/perf/util/zlib.c Signed-off-by: Ingo Molnar

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