kernel/tools/perf/util/srcline.c, branch linux-5.2.y

perf report: Don't shadow inlined symbol with different addr range

2019-02-19T15:30:12Z

We can't assume inlined symbols with the same name are equal, because their address range may be different. This will cause the symbols with different addresses be shadowed when adding to the hist entry, and lead to ERANGE error when checking the symbol address during sample parse, the addr should be within the range of [sym.start, sym.end]. The error message is like: "0x36aea60 [0x8]: failed to process type: 68". The second parameter of symbol__new() is the length of the fake symbol for the inline frame, which is the subtraction of the end and start address of base_sym. Signed-off-by: He Kuang Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Milian Wolff Cc: Namhyung Kim Cc: Peter Zijlstra Fixes: aa441895f7b4 ("perf report: Compare symbol name for inlined frames when sorting") Link: http://lkml.kernel.org/r/20190219130531.15692-1-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Use cached rbtrees

2019-01-25T14:12:09Z

At the cost of an extra pointer, we can avoid the O(logN) cost of finding the first element in the tree (smallest node), which is something required for nearly every in/srcline callchain node deletion (in/srcline__tree_delete()). Signed-off-by: Davidlohr Bueso Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/20181206191819.30182-4-dave@stgolabs.net Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Support 'srccode' output

2018-12-17T17:57:07Z

When looking at PT or brstackinsn traces with 'perf script' it can be very useful to see the source code. This adds a simple facility to print them with 'perf script', if the information is available through dwarf % perf record ... % perf script -F insn,ip,sym,srccode ... 4004c6 main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004c6 main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004b3 main 6 v++; % perf record -b ... % perf script -F insn,ip,sym,srccode,brstackinsn ... main+22: 0000000000400543 insn: e8 ca ff ff ff # PRED |18 f1(); f1: 0000000000400512 insn: 55 |10 { 0000000000400513 insn: 48 89 e5 0000000000400516 insn: b8 00 00 00 00 |11 f2(); 000000000040051b insn: e8 d6 ff ff ff # PRED f2: 00000000004004f6 insn: 55 |5 { 00000000004004f7 insn: 48 89 e5 00000000004004fa insn: 8b 05 2c 0b 20 00 |6 c = a / b; 0000000000400500 insn: 8b 0d 2a 0b 20 00 0000000000400506 insn: 99 0000000000400507 insn: f7 f9 0000000000400509 insn: 89 05 29 0b 20 00 000000000040050f insn: 90 |7 } 0000000000400510 insn: 5d 0000000000400511 insn: c3 # PRED f1+14: 0000000000400520 insn: b8 00 00 00 00 |12 f2(); 0000000000400525 insn: e8 cc ff ff ff # PRED f2: 00000000004004f6 insn: 55 |5 { 00000000004004f7 insn: 48 89 e5 00000000004004fa insn: 8b 05 2c 0b 20 00 |6 c = a / b; Not supported for callchains currently, would need some layout changes there. Committer notes: Fixed the build on Alpine Linux (3.4 .. 3.8) by addressing this warning: In file included from util/srccode.c:19:0: /usr/include/sys/fcntl.h:1:2: error: #warning redirecting incorrect #include to [-Werror=cpp] #warning redirecting incorrect #include to ^~~~~~~ cc1: all warnings being treated as errors Signed-off-by: Andi Kleen Tested-by: Jiri Olsa Link: http://lkml.kernel.org/r/20181204001848.24769-1-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo

perf report: Don't crash on invalid inline debug information

2018-10-16T17:52:21Z

When the function name for an inline frame is invalid, we must not try to demangle this symbol, otherwise we crash with: #0 0x0000555555895c01 in bfd_demangle () #1 0x0000555555823262 in demangle_sym (dso=0x555555d92b90, elf_name=0x0, kmodule=0) at util/symbol-elf.c:215 #2 dso__demangle_sym (dso=dso@entry=0x555555d92b90, kmodule=, kmodule@entry=0, elf_name=elf_name@entry=0x0) at util/symbol-elf.c:400 #3 0x00005555557fef4b in new_inline_sym (funcname=0x0, base_sym=0x555555d92b90, dso=0x555555d92b90) at util/srcline.c:89 #4 inline_list__append_dso_a2l (dso=dso@entry=0x555555c7bb00, node=node@entry=0x555555e31810, sym=sym@entry=0x555555d92b90) at util/srcline.c:264 #5 0x00005555557ff27f in addr2line (dso_name=dso_name@entry=0x555555d92430 "/home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf", addr=addr@entry=2888, file=file@entry=0x0, line=line@entry=0x0, dso=dso@entry=0x555555c7bb00, unwind_inlines=unwind_inlines@entry=true, node=0x555555e31810, sym=0x555555d92b90) at util/srcline.c:313 #6 0x00005555557ffe7c in addr2inlines (sym=0x555555d92b90, dso=0x555555c7bb00, addr=2888, dso_name=0x555555d92430 "/home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf") at util/srcline.c:358 So instead handle the case where we get invalid function names for inlined frames and use a fallback '??' function name instead. While this crash was originally reported by Hadrien for rust code, I can now also reproduce it with trivial C++ code. Indeed, it seems like libbfd fails to interpret the debug information for the inline frame symbol name: $ addr2line -e /home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf -if b48 main /usr/include/c++/8.2.1/complex:610 ?? /usr/include/c++/8.2.1/complex:618 ?? /usr/include/c++/8.2.1/complex:675 ?? /usr/include/c++/8.2.1/complex:685 main /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 I've reported this bug upstream and also attached a patch there which should fix this issue: https://sourceware.org/bugzilla/show_bug.cgi?id=23715 Reported-by: Hadrien Grasland Signed-off-by: Milian Wolff Cc: Jin Yao Cc: Jiri Olsa Cc: Namhyung Kim Fixes: a64489c56c30 ("perf report: Find the inline stack for a given address") [ The above 'Fixes:' cset is where originally the problem was introduced, i.e. using a2l->funcname without checking if it is NULL, but this current patch fixes the current codebase, i.e. multiple csets were applied after a64489c56c30 before the problem was reported by Hadrien ] Link: http://lkml.kernel.org/r/20180926135207.30263-3-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Store the ELF symbol type in the symbol struct

2018-04-26T16:47:18Z

There is code that needs to see if a resolved address is a function, so, since we're going to ditch the MAP__{FUNCTION,VARIABLE} split, store that info in the per symbol struct. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-9ugwxz0i8ryg5702rx8u5q6z@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf report: Fix a wrong offset issue when using /proc/kcore

2018-01-08T14:11:57Z

When a valid vmlinux is not found, 'perf report' falls back to look at /proc/kcore. In this case, it will report the impossible large offset. For example: # perf record -b -e cycles:k find /etc/ > /dev/null # perf report --stdio --branch-history 22.77% _vm_normal_page+18446603336221188162 | ---page_remove_rmap +18446603336221188324 page_remove_rmap +18446603336221188487 (cycles:5) unlock_page_memcg +18446603336221188096 page_remove_rmap +18446603336221188327 (cycles:1) The issue is the value which is passed to parameter 'addr' in __get_srcline() is the objdump address. It's not correct if we calculate the offset by using 'addr - sym->start'. This patch creates a new parameter 'ip' in __get_srcline(). It is not converted to objdump address. With this patch, the perf report output is: 22.77% _vm_normal_page+66 | ---page_remove_rmap +228 page_remove_rmap +391 (cycles:5) unlock_page_memcg +0 page_remove_rmap +231 (cycles:1) page_remove_rmap +236 Committer testing: Make sure you get any valid vmlinux out of the way, using '-v' on the 'perf report' case and deleting it from places where perf searches them, like your kernel build dir and the build-id cache, in ~/.debug/. Reported-by: Arnaldo Carvalho de Melo Signed-off-by: Jin Yao 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/1514564812-17344-1-git-send-email-yao.jin@linux.intel.com 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

perf srcline: Show correct function name for srcline of callchains

2017-11-01T14:44:38Z

When libbfd is not used, it doesn't show proper function name and reuse the original symbol of the sample. That's because it passes the original sym to inline_list__append(). As `addr2line -f` returns function names as well, use that to create an inline_sym and pass it to inline_list__append(). For example, following data shows that inlined entries of main have same name (main). Before: $ perf report -g srcline -q | head 45.22% inlining libm-2.26.so [.] __hypot_finite | ---__hypot_finite ??:0 | |--44.15%--hypot ??:0 | main complex:589 | main complex:597 | main complex:654 | main complex:664 | main inlining.cpp:14 After: $ perf report -g srcline -q | head 45.22% inlining libm-2.26.so [.] __hypot_finite | ---__hypot_finite | |--44.15%--hypot | std::__complex_abs complex:589 (inlined) | std::abs complex:597 (inlined) | std::_Norm_helper::_S_do_it complex:654 (inlined) | std::norm complex:664 (inlined) | main inlining.cpp:14 Signed-off-by: Namhyung Kim Reviewed-by: Jiri Olsa Reviewed-by: Milian Wolff Cc: Jin Yao Cc: Peter Zijlstra Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20171031020654.31163-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Fix memory leak in addr2inlines()

2017-11-01T14:43:56Z

When libbfd is not used, addr2inlines() executes `addr2line -i` and process output line by line. But it resets filename to NULL in the loop so getline() allocates additional memory everytime instead of realloc. Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Jin Yao Cc: Milian Wolff Cc: Peter Zijlstra Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20171031020654.31163-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo