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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-25perf report: Cache srclines for callchain nodesMilian Wolff1-3/+14
On one hand this ensures that the memory is properly freed when the DSO gets freed. On the other hand this significantly speeds up the processing of the callchain nodes when lots of srclines are requested. For one of my data files e.g.: Before: Performance counter stats for 'perf report -s srcline -g srcline --stdio': 52496.495043 task-clock (msec) # 0.999 CPUs utilized 634 context-switches # 0.012 K/sec 2 cpu-migrations # 0.000 K/sec 191,561 page-faults # 0.004 M/sec 165,074,498,235 cycles # 3.144 GHz 334,170,832,408 instructions # 2.02 insn per cycle 90,220,029,745 branches # 1718.591 M/sec 654,525,177 branch-misses # 0.73% of all branches 52.533273822 seconds time elapsedProcessed 236605 events and lost 40 chunks! After: Performance counter stats for 'perf report -s srcline -g srcline --stdio': 22606.323706 task-clock (msec) # 1.000 CPUs utilized 31 context-switches # 0.001 K/sec 0 cpu-migrations # 0.000 K/sec 185,471 page-faults # 0.008 M/sec 71,188,113,681 cycles # 3.149 GHz 133,204,943,083 instructions # 1.87 insn per cycle 34,886,384,979 branches # 1543.214 M/sec 278,214,495 branch-misses # 0.80% of all branches 22.609857253 seconds time elapsed Note that the difference is only this large when `--inline` is not passed. In such situations, we would use the inliner cache and thus do not run this code path that often. I think that this cache should actually be used in other places, too. When looking at the valgrind leak report for perf report, we see tons of srclines being leaked, most notably from calls to hist_entry__get_srcline. The problem is that get_srcline has many different formatting options (show_sym, show_addr, potentially even unwind_inlines when calling __get_srcline directly). As such, the srcline cannot easily be cached for all calls, or we'd have to add caches for all formatting combinations (6 so far). An alternative would be to remove the formatting options and handle that on a different level - i.e. print the sym/addr on demand wherever we actually output something. And the unwind_inlines could be moved into a separate function that does not return the srcline. Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Reviewed-by: 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20171019113836.5548-4-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-10-25perf report: Cache failed lookups of inlined framesMilian Wolff1-8/+7
When no inlined frames could be found for a given address, we did not store this information anywhere. That means we potentially do the costly inliner lookup repeatedly for cases where we know it can never succeed. This patch makes dso__parse_addr_inlines always return a valid inline_node. It will be empty when no inliners are found. This enables us to cache the empty list in the DSO, thereby improving the performance when many addresses fail to find the inliners. For my trivial example, the performance impact is already quite significant: Before: ~~~~~ Performance counter stats for 'perf report --stdio --inline -g srcline -s srcline' (5 runs): 594.804032 task-clock (msec) # 0.998 CPUs utilized ( +- 0.07% ) 53 context-switches # 0.089 K/sec ( +- 4.09% ) 0 cpu-migrations # 0.000 K/sec ( +-100.00% ) 5,687 page-faults # 0.010 M/sec ( +- 0.02% ) 2,300,918,213 cycles # 3.868 GHz ( +- 0.09% ) 4,395,839,080 instructions # 1.91 insn per cycle ( +- 0.00% ) 939,177,205 branches # 1578.969 M/sec ( +- 0.00% ) 11,824,633 branch-misses # 1.26% of all branches ( +- 0.10% ) 0.596246531 seconds time elapsed ( +- 0.07% ) ~~~~~ After: ~~~~~ Performance counter stats for 'perf report --stdio --inline -g srcline -s srcline' (5 runs): 113.111405 task-clock (msec) # 0.990 CPUs utilized ( +- 0.89% ) 29 context-switches # 0.255 K/sec ( +- 54.25% ) 0 cpu-migrations # 0.000 K/sec 5,380 page-faults # 0.048 M/sec ( +- 0.01% ) 432,378,779 cycles # 3.823 GHz ( +- 0.75% ) 670,057,633 instructions # 1.55 insn per cycle ( +- 0.01% ) 141,001,247 branches # 1246.570 M/sec ( +- 0.01% ) 2,346,845 branch-misses # 1.66% of all branches ( +- 0.19% ) 0.114222393 seconds time elapsed ( +- 1.19% ) ~~~~~ Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Reviewed-by: 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20171019113836.5548-3-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-10-24perf callchain: Create real callchain entries for inlined framesMilian Wolff1-0/+37
The inline_node structs are maintained by the new dso->inlines tree. This in turn keeps ownership of the fake symbols and srcline string representing an inline frame. This tree is sorted by address to allow quick lookups. All other entries of the symbol beside the function name are unused for inline frames. The advantage of this approach is that all existing users of the callchain API can now transparently display inlined frames without having to patch their code. Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Reviewed-by: Jiri Olsa <jolsa@redhat.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Yao Jin <yao.jin@linux.intel.com> Link: http://lkml.kernel.org/r/20171009203310.17362-6-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-10-24perf callchain: Store srcline in callchain_cursor_nodeMilian Wolff1-2/+16
This is mostly a preparation to enable the creation of full callchain nodes for inline frames. Such frames will reference the IP of the non-inlined frame, but hold the symbol and srcline for an inlined location. As such, we won't be able to query the srcline on-demand based on the IP alone. Instead, we will leverage the functionality provided by this patch here, and store the srcline for the inlined nodes in the new srcline member of callchain_cursor_node. Note that this patch on its own leaks the srcline, as there is no free_callchain_cursor_node or similar. A future patch will add caching of the srcline and handle deletion properly. Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Reviewed-by: Jiri Olsa <jolsa@redhat.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Yao Jin <yao.jin@linux.intel.com> Link: http://lkml.kernel.org/r/20171009203310.17362-3-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-10-03perf top: Implement multithreading for perf_event__synthesize_threadsKan Liang1-2/+6
The proc files which is sorted with alphabetical order are evenly assigned to several synthesize threads to be processed in parallel. For 'perf top', the threads number hard code to online CPU number. The following patch will introduce an option to set it. For other perf tools, the thread number is 1. Because the process function is not ready for multithreading, e.g. process_synthesized_event. This patch series only support event synthesize multithreading for 'perf top'. For other tools, it can be done separately later. With multithread applied, the total processing time can get up to 1.56x speedup on Knights Mill for 'perf top'. For specific single event processing, the processing time could increase because of the lock contention. So proc_map_timeout may need to be increased. Otherwise some proc maps will be truncated. Based on my test, increasing the proc_map_timeout has small impact on the total processing time. The total processing time still get 1.49x speedup on Knights Mill after increasing the proc_map_timeout. The patch itself doesn't increase the proc_map_timeout. Doesn't need to implement multithreading for per task monitoring, perf_event__synthesize_thread_map. It doesn't have performance issue. Committer testing: # getconf _NPROCESSORS_ONLN 4 # perf trace --no-inherit -e clone -o /tmp/output perf top # tail -4 /tmp/bla 0.124 ( 0.041 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3eb3a8f30, parent_tidptr: 0x7fc3eb3a99d0, child_tidptr: 0x7fc3eb3a99d0, tls: 0x7fc3eb3a9700) = 9548 (perf) 0.246 ( 0.023 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3eaba7f30, parent_tidptr: 0x7fc3eaba89d0, child_tidptr: 0x7fc3eaba89d0, tls: 0x7fc3eaba8700) = 9549 (perf) 0.286 ( 0.019 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3ea3a6f30, parent_tidptr: 0x7fc3ea3a79d0, child_tidptr: 0x7fc3ea3a79d0, tls: 0x7fc3ea3a7700) = 9550 (perf) 246.540 ( 0.047 ms): clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7fc3ea3a6f30, parent_tidptr: 0x7fc3ea3a79d0, child_tidptr: 0x7fc3ea3a79d0, tls: 0x7fc3ea3a7700) = 9551 (perf) # Signed-off-by: Kan Liang <kan.liang@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: He Kuang <hekuang@huawei.com> Cc: Lukasz Odzioba <lukasz.odzioba@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1506696477-146932-4-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-09-21perf tools: Provide mutex wrappers for pthreads rwlocksArnaldo Carvalho de Melo1-20/+21
Andi reported a performance drop in single threaded perf tools such as 'perf script' due to the growing number of locks being put in place to allow for multithreaded tools, so wrap the POSIX threads rwlock routines with the names used for such kinds of locks in the Linux kernel and then allow for tools to ask for those locks to be used or not. I.e. a tool may have a multithreaded phase and then switch to single threaded, like the upcoming patches for the synthesizing of PERF_RECORD_{FORK,MMAP,etc} for pre-existing processes to then switch to single threaded mode in 'perf top'. The init routines will not be conditional, this way starting as single threaded to then move to multi threaded mode should be possible. Reported-by: Andi Kleen <ak@linux.intel.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/20170404161739.GH12903@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-09-18perf machine: Optimize a bit the machine__findnew_thread() methodsArnaldo Carvalho de Melo1-3/+3
In some cases we already have calculated the hash bucket, so reuse it. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Lukasz Odzioba <lukasz.odzioba@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-800zehjsyy03er4s4jf0e99v@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-09-18perf machine: Use hashtable for machine threadsKan Liang1-51/+85
To process any events, it needs to find the thread in the machine first. The machine maintains a rb tree to store all threads. The rb tree is protected by a rw lock. It is not a problem for current perf which serially processing events. However, it will have scalability performance issue to process events in parallel, especially on a heavy load system which have many threads. Introduce a hashtable to divide the big rb tree into many samll rb tree for threads. The index is thread id % hashtable size. It can reduce the lock contention. Committer notes: Renamed some variables and function names to reduce semantic confusion: 'struct threads' pointers: thread -> threads threads hastable index: tid -> hash_bucket struct threads *machine__thread() -> machine__threads() Cast tid to (unsigned int) to handle -1 in machine__threads() (Kan Liang) Signed-off-by: Kan Liang <kan.liang@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Lukasz Odzioba <lukasz.odzioba@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1505096603-215017-2-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-09-01perf sort: Add sort option for physical addressKan Liang1-2/+6
Add a new sort option "phys_daddr" for --mem-mode sort. With this option applied, perf can sort and report by sample's physical address. Signed-off-by: Kan Liang <kan.liang@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Stephane Eranian <eranian@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1504026672-7304-3-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-08-30perf report: Calculate the average cycles of iterationsJin Yao1-35/+53
The branch history code has a loop detection function. With this, we can get the number of iterations by calculating the removed loops. While it would be nice for knowing the average cycles of iterations. This patch adds up the cycles in branch entries of removed loops and save the result to the next branch entry (e.g. branch entry A). Finally it will display the iteration number and average cycles at the "from" of branch entry A. For example: perf record -g -j any,save_type ./div perf report --branch-history --no-children --stdio --22.63%--main div.c:42 (RET CROSS_2M) compute_flag div.c:28 (cycles:2 iter:173115 avg_cycles:2) | --10.73%--compute_flag div.c:27 (RET CROSS_2M) rand rand.c:28 (cycles:1) rand rand.c:28 (RET CROSS_2M) __random random.c:298 (cycles:1) __random random.c:297 (COND_BWD CROSS_2M) __random random.c:295 (cycles:1) __random random.c:295 (COND_BWD CROSS_2M) __random random.c:295 (cycles:1) __random random.c:295 (RET CROSS_2M) Signed-off-by: Yao Jin <yao.jin@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1502111115-18305-1-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-08-11perf record: Fix wrong size in perf_record_mmap for last kernel moduleThomas Richter1-1/+3
During work on perf report for s390 I ran into the following issue: 0 0x318 [0x78]: PERF_RECORD_MMAP -1/0: [0x3ff804d6990(0xfffffc007fb2966f) @ 0]: x /lib/modules/4.12.0perf1+/kernel/drivers/s390/net/qeth_l2.ko This is a PERF_RECORD_MMAP entry of the perf.data file with an invalid module size for qeth_l2.ko (the s390 ethernet device driver). Even a mainframe does not have 0xfffffc007fb2966f bytes of main memory. It turned out that this wrong size is created by the perf record command. What happens is this function call sequence from __cmd_record(): perf_session__new(): perf_session__create_kernel_maps(): machine__create_kernel_maps(): machine__create_modules(): Creates map for all loaded kernel modules. modules__parse(): Reads /proc/modules and extracts module name and load address (1st and last column) machine__create_module(): Called for every module found in /proc/modules. Creates a new map for every module found and enters module name and start address into the map. Since the module end address is unknown it is set to zero. This ends up with a kernel module map list sorted by module start addresses. All module end addresses are zero. Last machine__create_kernel_maps() calls function map_groups__fixup_end(). This function iterates through the maps and assigns each map entry's end address the successor map entry start address. The last entry of the map group has no successor, so ~0 is used as end to consume the remaining memory. Later __cmd_record calls function record__synthesize() which in turn calls perf_event__synthesize_kernel_mmap() and perf_event__synthesize_modules() to create PERF_REPORT_MMAP entries into the perf.data file. On s390 this results in the last module qeth_l2.ko (which has highest start address, see module table: [root@s8360047 perf]# cat /proc/modules qeth_l2 86016 1 - Live 0x000003ff804d6000 qeth 266240 1 qeth_l2, Live 0x000003ff80296000 ccwgroup 24576 1 qeth, Live 0x000003ff80218000 vmur 36864 0 - Live 0x000003ff80182000 qdio 143360 2 qeth_l2,qeth, Live 0x000003ff80002000 [root@s8360047 perf]# ) to be the last entry and its map has an end address of ~0. When the PERF_RECORD_MMAP entry is created for kernel module qeth_l2.ko its start address and length is written. The length is calculated in line: event->mmap.len = pos->end - pos->start; and results in 0xffffffffffffffff - 0x3ff804d6990(*) = 0xfffffc007fb2966f (*) On s390 the module start address is actually determined by a __weak function named arch__fix_module_text_start() in machine__create_module(). I think this improvable. We can use the module size (2nd column of /proc/modules) to get each loaded kernel module size and calculate its end address. Only for map entries which do not have a valid end address (end is still zero) we can use the heuristic we have now, that is use successor start address or ~0. Signed-off-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com> LPU-Reference: 20170803134902.47207-2-tmricht@linux.vnet.ibm.com Link: http://lkml.kernel.org/n/tip-nmoqij5b5vxx7rq2ckwu8iaj@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-25perf report: Make --branch-history work without callgraphs(-g) option in perf recordJin Yao1-1/+12
perf record -b -g <command> perf report --branch-history This merges the LBRs with the callgraphs. However it would be nice if it also works without callgraphs (-g) set in perf record, so that only the LBRs are displayed. But currently perf report errors in this case. For example, perf record -b <command> perf report --branch-history Error: Selected -g or --branch-history but no callchain data. Did you call 'perf record' without -g? This patch displays the LBRs only even if callgraphs(-g) is not enabled in perf record. Change log: v2: According to Milian Wolff's comment, change the obsolete error message. Now the error message is: ┌─Error:─────────────────────────────────────┐ │Selected -g or --branch-history. │ │But no callchain or branch data. │ │Did you call 'perf record' without -g or -b?│ │ │ │ │ │Press any key... │ └────────────────────────────────────────────┘ When passing the last parameter to hists__fprintf, changes "|" to "||". hists__fprintf(hists, !quiet, 0, 0, rep->min_percent, stdout, symbol_conf.use_callchain || symbol_conf.show_branchflag_count); Signed-off-by: Yao Jin <yao.jin@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1494240182-28899-1-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-18perf report: Show branch type in callchain entryJin Yao1-9/+17
Show branch type in callchain entry. The branch type is printed with other LBR information (such as cycles/abort/...). For example: perf record -g -j any,save_type perf report --branch-history --stdio --no-children 38.50% div.c:45 [.] main div | ---main div.c:42 (RET CROSS_2M cycles:2) compute_flag div.c:28 (cycles:2) compute_flag div.c:27 (RET CROSS_2M cycles:1) rand rand.c:28 (cycles:1) rand rand.c:28 (RET CROSS_2M cycles:1) __random random.c:298 (cycles:1) __random random.c:297 (COND_BWD CROSS_2M cycles:1) __random random.c:295 (cycles:1) __random random.c:295 (COND_BWD CROSS_2M cycles:1) __random random.c:295 (cycles:1) __random random.c:295 (RET CROSS_2M cycles:9) Change log v6: Remove the branch_type_str() since it's moved to branch.c. v5: Rewrite the branch info print code in util/callchain.c. v4: Comparing to previous version, the major changes are: Signed-off-by: Yao Jin <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: Kan Liang <kan.liang@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1500379995-6449-8-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-18perf buildid-cache: Cache debuginfoKrister Johansen1-1/+2
If a stripped binary is placed in the cache, the user is in a situation where there's a cached elf file present, but it doesn't have any symtab to use for name resolution. Grab the debuginfo for binaries that don't end in .ko. This yields a better chance of resolving symbols from older traces. Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1499305693-1599-7-git-send-email-kjlx@templeofstupid.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-18perf maps: Lookup maps in both intitial mountns and inner mountns.Krister Johansen1-2/+2
If a process is in a mountns and has symbols in /tmp/perf-<pid>.map, look first in the namespace using the tgid for the pidns that the process might be in. If the map isn't found there, try looking in the mountns where perf is running, and use the tgid that's appropriate for perf's pid namespace. If all else fails, use the original pid. This allows us to locate a symbol map file in the mount namespace, if it was generated there. However, we also try the tool's /tmp in case it's there instead. Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1499305693-1599-3-git-send-email-kjlx@templeofstupid.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-12perf symbols: Accept zero as the kernel base addressArnaldo Carvalho de Melo1-1/+1
Which is the case in S/390, where symbols were not being resolved because machine__get_kernel_start was only setting machine->kernel_start when the just successfully loaded kernel symtab had its map->start set to !0, when it was left at (1ULL << 63) assuming a partitioning of the address space for user/kernel, which is not the case in S/390 nor in Sparc. So just check if map__load() was successfull and set machine->kernel_start to zero, fixing kernel symbol resolution on S/390. Test performed by Thomas: ---- I like this patch. I have done a new build and removed all my debug output to start from scratch. Without your patch I get this: # Samples: 4 of event 'cpu-clock' # Event count (approx.): 1000000 # # Children Self Command Shared Object Symbol # ........ ........ ....... ................ ........................ 75.00% 0.00% true [unknown] [k] 0x00000000004bedda | ---0x4bedda | |--50.00%--0x42693a | | | --25.00%--0x2a72e0 | 0x2af0ca | 0x3d1003fe4c0 | --25.00%--0x4272bc 0x26fa84 and with your patch (I just rebuilt the perf tool, nothing else and used the same perf.data file as input): # Samples: 4 of event 'cpu-clock' # Event count (approx.): 1000000 # # Children Self Command Shared Object Symbol # ........ ........ ....... .......................... .................................. 75.00% 0.00% true [kernel.vmlinux] [k] pgm_check_handler | ---pgm_check_handler do_dat_exception handle_mm_fault __handle_mm_fault filemap_map_pages | |--25.00%--rcu_read_lock_held | rcu_lockdep_current_cpu_online | 0x3d1003ff4c0 | --25.00%--lock_release Looks good to me.... ---- Reported-and-Tested-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com> Link: http://lkml.kernel.org/n/tip-dk0n1uzmbe0tbthrpfqlx6bz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-06-26perf machine: Fix segfault for kernel.kptr_restrict=2Jiri Olsa1-4/+6
Michael reported the segfault when kernel.kptr_restrict=2 is set. $ perf record ls ... perf: Segmentation fault Obtained 16 stack frames. ./perf(dump_stack+0x2d) [0x5068df] ./perf(sighandler_dump_stack+0x2d) [0x5069bf] ./perf() [0x43e47b] /lib64/libc.so.6(+0x3594f) [0x7f762004794f] /lib64/libc.so.6(strlen+0x26) [0x7f762009ef86] /lib64/libc.so.6(__strdup+0xd) [0x7f762009ecbd] ./perf(maps__set_kallsyms_ref_reloc_sym+0x4d) [0x51590f] ./perf(machine__create_kernel_maps+0x136) [0x50a7de] ./perf(perf_session__create_kernel_maps+0x2c) [0x510a81] ./perf(perf_session__new+0x13d) [0x510e23] ./perf() [0x43fd61] ./perf(cmd_record+0x704) [0x441823] ./perf() [0x4bc1a0] ./perf() [0x4bc40d] ./perf() [0x4bc55f] ./perf(main+0x2d5) [0x4bc939] Segmentation fault (core dumped) The reason is that with kernel.kptr_restrict=2, we don't get the symbol from machine__get_running_kernel_start, which we want to use in maps__set_kallsyms_ref_reloc_sym and we crash. Check the symbol name value before calling maps__set_kallsyms_ref_reloc_sym() and succeed without ref_reloc_sym being set. It's safe because we check its existence before we use it. Reported-by: Michael Petlan <mpetlan@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20170626095153.553-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-06-05perf symbols: Set module info when build-id event foundNamhyung Kim1-10/+1
Like machine__findnew_module_dso(), it should set necessary info for kernel modules to find symbol info from the file. Factor out dso__set_module_info() to do it. This is needed for dso__needs_decompress() to detect such DSOs. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20170531120105.21731-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-05-02perf symbols: Accept symbols starting at address 0Arnaldo Carvalho de Melo1-11/+17
That is the case of _text on s390, and we have some functions that return an address, using address zero to report problems, oops. This would lead the symbol loading routines to not use "_text" as the reference relocation symbol, or the first symbol for the kernel, but use instead "_stext", that is at the same address on x86_64 and others, but not on s390: [acme@localhost perf-4.11.0-rc6]$ head -15 /proc/kallsyms 0000000000000000 T _text 0000000000000418 t iplstart 0000000000000800 T start 000000000000080a t .base 000000000000082e t .sk8x8 0000000000000834 t .gotr 0000000000000842 t .cmd 0000000000000846 t .parm 000000000000084a t .lowcase 0000000000010000 T startup 0000000000010010 T startup_kdump 0000000000010214 t startup_kdump_relocated 0000000000011000 T startup_continue 00000000000112a0 T _ehead 0000000000100000 T _stext [acme@localhost perf-4.11.0-rc6]$ Which in turn would make 'perf test vmlinux' to fail because it wouldn't find the symbols before "_stext" in kallsyms. Fix it by using the return value only for errors and storing the address, when the symbol is successfully found, in a provided pointer arg. Before this patch: After: [acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1 1: vmlinux symtab matches kallsyms : --- start --- test child forked, pid 40693 Looking at the vmlinux_path (8 entries long) Using /usr/lib/debug/lib/modules/3.10.0-654.el7.s390x/vmlinux for symbols ERR : 0: _text not on kallsyms ERR : 0x418: iplstart not on kallsyms ERR : 0x800: start not on kallsyms ERR : 0x80a: .base not on kallsyms ERR : 0x82e: .sk8x8 not on kallsyms ERR : 0x834: .gotr not on kallsyms ERR : 0x842: .cmd not on kallsyms ERR : 0x846: .parm not on kallsyms ERR : 0x84a: .lowcase not on kallsyms ERR : 0x10000: startup not on kallsyms ERR : 0x10010: startup_kdump not on kallsyms ERR : 0x10214: startup_kdump_relocated not on kallsyms ERR : 0x11000: startup_continue not on kallsyms ERR : 0x112a0: _ehead not on kallsyms <SNIP warnings> test child finished with -1 ---- end ---- vmlinux symtab matches kallsyms: FAILED! [acme@localhost perf-4.11.0-rc6]$ After: [acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1 1: vmlinux symtab matches kallsyms : --- start --- test child forked, pid 47160 <SNIP warnings> test child finished with 0 ---- end ---- vmlinux symtab matches kallsyms: Ok [acme@localhost perf-4.11.0-rc6]$ Reported-by: Michael Petlan <mpetlan@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-9x9bwgd3btwdk1u51xie93fz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-24perf tools: Remove string.h, unistd.h and sys/stat.h from util.hArnaldo Carvalho de Melo1-0/+3
Not needed in this header, added to the places that need FILE, putchar(), access() and a few other prototypes. Link: http://lkml.kernel.org/n/tip-xxtdsl6nsna82j7puwbdjqhs@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19perf tools: Remove regex.h and fnmatch.h from util.hArnaldo Carvalho de Melo1-0/+1
The users of regex and fnmatch functions should include those headers instead. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ixzm5kuamsq1ixbkuv6kmwzj@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19perf tools: Remove include dirent.h from util.hArnaldo Carvalho de Melo1-0/+1
The files using the dirent.h routines should instead include it, reducing the includes hell that lead to longer build times. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-42g2f4z6nfg7mdb2ae97n7tj@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19perf tools: Include errno.h where neededArnaldo Carvalho de Melo1-0/+1
Removing it from util.h, part of an effort to disentangle the includes hell, that makes changes to util.h or something included by it to cause a complete rebuild of the tools. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ztrjy52q1rqcchuy3rubfgt2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19perf tools: Move sane ctype stuff from util.h to sane_ctype.hArnaldo Carvalho de Melo1-1/+3
More stuff that came from git, out of the hodge-podge that is util.h Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-e3lana4gctz3ub4hn4y29hkw@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19perf tools: Including missing inttypes.h headerArnaldo Carvalho de Melo1-0/+1
Needed to use the PRI[xu](32,64) formatting macros. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-wkbho8kaw24q67dd11q0j39f@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-14perf tools: Add PERF_RECORD_NAMESPACES to include namespaces related infoHari Bathini1-0/+34
Introduce a new option to record PERF_RECORD_NAMESPACES events emitted by the kernel when fork, clone, setns or unshare are invoked. And update perf-record documentation with the new option to record namespace events. Committer notes: Combined it with a later patch to allow printing it via 'perf report -D' and be able to test the feature introduced in this patch. Had to move here also perf_ns__name(), that was introduced in another later patch. Also used PRIu64 and PRIx64 to fix the build in some enfironments wrt: util/event.c:1129:39: error: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'long long unsigned int' [-Werror=format=] ret += fprintf(fp, "%u/%s: %lu/0x%lx%s", idx ^ Testing it: # perf record --namespaces -a ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 1.083 MB perf.data (423 samples) ] # # perf report -D <SNIP> 3 2028902078892 0x115140 [0xa0]: PERF_RECORD_NAMESPACES 14783/14783 - nr_namespaces: 7 [0/net: 3/0xf0000081, 1/uts: 3/0xeffffffe, 2/ipc: 3/0xefffffff, 3/pid: 3/0xeffffffc, 4/user: 3/0xeffffffd, 5/mnt: 3/0xf0000000, 6/cgroup: 3/0xeffffffb] 0x1151e0 [0x30]: event: 9 . . ... raw event: size 48 bytes . 0000: 09 00 00 00 02 00 30 00 c4 71 82 68 0c 7f 00 00 ......0..q.h.... . 0010: a9 39 00 00 a9 39 00 00 94 28 fe 63 d8 01 00 00 .9...9...(.c.... . 0020: 03 00 00 00 00 00 00 00 ce c4 02 00 00 00 00 00 ................ <SNIP> NAMESPACES events: 1 <SNIP> # Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Aravinda Prasad <aravinda@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sargun Dhillon <sargun@sargun.me> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/148891930386.25309.18412039920746995488.stgit@hbathini.in.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-03perf thread: convert thread.refcnt from atomic_t to refcount_tElena Reshetova1-1/+1
The refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Kook <keescook@chromium.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Windsor <dwindsor@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hans Liljestrand <ishkamiel@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kees Kook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: alsa-devel@alsa-project.org Link: http://lkml.kernel.org/r/1487691303-31858-9-git-send-email-elena.reshetova@intel.com [ Did missing conversion in __machine__remove_thread() ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-14perf tools: Be consistent on the type of map->symbols[] interatorArnaldo Carvalho de Melo1-2/+2
In a few cases we were using 'enum map_type' and that triggered this warning when using clang: util/session.c:1923:16: error: comparison of constant 2 with expression of type 'enum map_type' is always true [-Werror,-Wtautological-constant-out-of-range-compare] for (i = 0; i < MAP__NR_TYPES; ++i) { Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-i6uyo6bsopa2dghnx8qo7rri@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-13perf symbols: No need to check if sym->name is NULLArnaldo Carvalho de Melo1-1/+1
As it is an array, so will always evaluate to 'true', as reported by clang: builtin-sched.c:2070:19: error: address of array 'sym->name' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion] if (sym && sym->name) { ~~ ~~~~~^~~~ 1 warning generated. So just ditch all those useless checks. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ydpm927col06paixb775jjx5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-11perf machine: Add a kallsyms loading constructorArnaldo Carvalho de Melo1-0/+19
To reduce the boilerplate for searching for functions in the running kernel and modules. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-93iqzayafpaxaguoiwjqezgz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-11-14perf report: Add branch flag to callchain cursor nodeJin Yao1-15/+67
Since the branch ip has been added to call stack for easier browsing, this patch adds more branch information. For example, add a flag to indicate if this ip is a branch, and also add with the branch flag. Then we can know if the cursor node represents a branch and know what the branch flag it has. The branch history code has a loop detection pass that removes loops. It would be nice for knowing how many loops were removed then in next steps, we can compute out the average number of iterations. For example: Before remove_loops(), entry0: from = 0x100, to = 0x200 entry1: from = 0x300, to = 0x250 entry2: from = 0x300, to = 0x250 entry3: from = 0x300, to = 0x250 entry4: from = 0x700, to = 0x800 After remove_loops() entry0: from = 0x100, to = 0x200 entry1: from = 0x300, to = 0x250 entry2: from = 0x700, to = 0x800 The original entry2 and entry3 are removed. So the number of iterations (from = 0x300, to = 0x250) is equal to removed number + 1 (2 + 1). iterations = removed number + 1; average iteractions = Sum(iteractions) / number of samples This formula ignores other cases, for example, iterations cross multiple buffers and one buffer contains 2+ loops. Because in practice, it's good enough. Signed-off-by: Yao Jin <yao.jin@linux.intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Linux-kernel@vger.kernel.org Cc: Yao Jin <yao.jin@linux.intel.com> Link: http://lkml.kernel.org/n/1477876794-30749-2-git-send-email-yao.jin@linux.intel.com [ Renamed 'iter' to 'nr_loop_iter' for clarity ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-03perf tools: Experiment with cppcheckArnaldo Carvalho de Melo1-3/+3
Experimenting a bit using cppcheck[1], a static checker brought to my attention by Colin, reducing the scope of some variables, reducing the line of source code lines in the process: $ cppcheck --enable=style tools/perf/util/thread.c Checking tools/perf/util/thread.c... [tools/perf/util/thread.c:17]: (style) The scope of the variable 'leader' can be reduced. [tools/perf/util/thread.c:133]: (style) The scope of the variable 'err' can be reduced. [tools/perf/util/thread.c:273]: (style) The scope of the variable 'err' can be reduced. Will continue later, but these are already useful, keep them. 1: https://sourceforge.net/p/cppcheck/wiki/Home/ Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ixws7lbycihhpmq9cc949ti6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-05perf symbols: Remove symbol_filter_t machineryArnaldo Carvalho de Melo1-10/+9
We're not using it anymore, few users were, but we really could do without it, simplify lots of functions by removing it. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-1zng8wdznn00iiz08bb7q3vn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-05perf machine: Remove machine->symbol_filter and friendsArnaldo Carvalho de Melo1-20/+1
Including machines__set_symbol_filter(), not used anymore. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-7o1qgmrpvzuis4a9f0t8mnri@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-26perf s390: Fix 'start' address of module's mapSong Shan Gong1-0/+8
At present, when creating module's map, perf gets 'start' address by parsing '/proc/modules', but it's the module base address, it isn't the start address of the '.text' section. In most arches, it's OK. But for s390, it places 'GOT' and 'PLT' relocations before '.text' section. So there exists an offset between module base address and '.text' section, which will incur wrong symbol resolution for modules. Fix this bug by getting 'start' address of module's map from parsing '/sys/module/[module name]/sections/.text', not from '/proc/modules'. Signed-off-by: Song Shan Gong <gongss@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Link: http://lkml.kernel.org/r/1469070651-6447-2-git-send-email-gongss@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-22perf machine: Destructors should accept NULLArnaldo Carvalho de Melo1-2/+4
And do nothing, just like free(), to avoid having to test it in callers, usually in error paths. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-q42gj3b3znhho9z1mrbo4jce@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-08Merge tag 'perf-core-for-mingo-20160607' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/coreIngo Molnar1-2/+12
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: User visible changes: - Support cross unwinding, i.e. collecting '--call-graph dwarf' perf.data files in one machine and then doing analysis in another machine of a different hardware architecture. This enables, for instance, to do: perf record -a --call-graph dwarf on a x86-32 or aarch64 system and then do 'perf report' on it on a x86_64 workstation. (He Kuang) - Fix crash in build_id_cache__kallsyms_path(), recent regression (Wang Nan) Infrastructure changes: - Make tools/lib/bpf use the IS_ERR return facility consistently and also stop using the _get_ term for non-reference count methods (Arnaldo Carvalho de Melo) - 'perf config' refactorings (Taeung Song) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-07perf unwind: Move unwind__prepare_access from thread_new into thread__insert_mapHe Kuang1-2/+12
To determine the libunwind methods to use, we should get the 32bit/64bit information from maps of a thread. When a thread is newly created, the information is not prepared. This patch moves unwind__prepare_access() into thread__insert_map() so we can get the information we need from maps. Meanwhile, let thread__insert_map() return value and show messages on error. Signed-off-by: He Kuang <hekuang@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1464924803-22214-5-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-25Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-20/+15
Pull perf updates from Ingo Molnar: "Mostly tooling and PMU driver fixes, but also a number of late updates such as the reworking of the call-chain size limiting logic to make call-graph recording more robust, plus tooling side changes for the new 'backwards ring-buffer' extension to the perf ring-buffer" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) perf record: Read from backward ring buffer perf record: Rename variable to make code clear perf record: Prevent reading invalid data in record__mmap_read perf evlist: Add API to pause/resume perf trace: Use the ptr->name beautifier as default for "filename" args perf trace: Use the fd->name beautifier as default for "fd" args perf report: Add srcline_from/to branch sort keys perf evsel: Record fd into perf_mmap perf evsel: Add overwrite attribute and check write_backward perf tools: Set buildid dir under symfs when --symfs is provided perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced perf annotate: Sort list of recognised instructions perf annotate: Fix identification of ARM blt and bls instructions perf tools: Fix usage of max_stack sysctl perf callchain: Stop validating callchains by the max_stack sysctl perf trace: Fix exit_group() formatting perf top: Use machine->kptr_restrict_warned perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1 perf machine: Do not bail out if not managing to read ref reloc symbol perf/x86/intel/p4: Trival indentation fix, remove space ...
2016-05-20perf callchain: Stop validating callchains by the max_stack sysctlArnaldo Carvalho de Melo1-20/+5
As thread__resolve_callchain_sample can be used for handling perf.data files, that could've been recorded with a large max_stack sysctl setting than what the system used for analysis has set. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-2995bt2g5yq2m05vga4kip6m@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-20perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1Arnaldo Carvalho de Melo1-0/+1
Hook into the libtraceevent plugin kernel symbol resolver to warn the user that that can't happen with kptr_restrict=1. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-9gc412xx1gl0lvqj1d1xwlyb@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-20perf machine: Do not bail out if not managing to read ref reloc symbolArnaldo Carvalho de Melo1-4/+5
This means the user can't access /proc/kallsyms, for instance, because /proc/sys/kernel/kptr_restrict is set to 1. Instead leave the ref_reloc_sym as NULL and code using it will cope. This allows 'perf trace' to work on such systems for !root, the only issue would be when trying to resolve kernel symbols, which happens, for instance, in some libtracevent plugins. A warning for that case will be provided in the next patch in this series. Noticed in Ubuntu 16.04, that comes with kptr_restrict=1. Reported-by: Milian Wolff <milian.wolff@kdab.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-knpu3z4iyp2dxpdfm798fac4@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-17Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivialLinus Torvalds1-1/+1
Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (21 commits) gitignore: fix wording mfd: ab8500-debugfs: fix "between" in printk memstick: trivial fix of spelling mistake on management cpupowerutils: bench: fix "average" treewide: Fix typos in printk IB/mlx4: printk fix pinctrl: sirf/atlas7: fix printk spelling serial: mctrl_gpio: Grammar s/lines GPIOs/line GPIOs/, /sets/set/ w1: comment spelling s/minmum/minimum/ Blackfin: comment spelling s/divsor/divisor/ metag: Fix misspellings in comments. ia64: Fix misspellings in comments. hexagon: Fix misspellings in comments. tools/perf: Fix misspellings in comments. cris: Fix misspellings in comments. c6x: Fix misspellings in comments. blackfin: Fix misspelling of 'register' in comment. avr32: Fix misspelling of 'definitions' in comment. treewide: Fix typos in printk Doc: treewide : Fix typos in DocBook/filesystem.xml ...
2016-05-16perf tools: Separate accounting of contexts and real addresses in a stack traceArnaldo Carvalho de Melo1-9/+17
The perf_sample->ip_callchain->nr value includes all the entries in the ip_callchain->ip[] array, real addresses and PERF_CONTEXT_{KERNEL,USER,etc}, while what the user expects is that what is in the kernel.perf_event_max_stack sysctl or in the upcoming per event perf_event_attr.sample_max_stack knob be honoured in terms of IP addresses in the stack trace. So match the kernel support and validate chain->nr taking into account both kernel.perf_event_max_stack and kernel.perf_event_max_contexts_per_stack. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-mgx0jpzfdq4uq4abfa40byu0@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-16perf symbols: Introduce DSO__NAME_KALLSYMS and DSO__NAME_KCOREMasami Hiramatsu1-1/+1
Instead of using a raw string, use DSO__NAME_KALLSYMS and DSO__NAME_KCORE macros for kallsyms and kcore. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20160515031935.4017.50971.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-06perf callchain: Fix incorrect ordering of entriesChris Phlipot1-15/+41
The existing implementation of thread__resolve_callchain, under certain circumstances, can assemble callchain entries in the incorrect order. The callchain entries are resolved incorrectly for a sample when all of the following conditions are met: 1. callchain_param.order is set to ORDER_CALLER 2. thread__resolve_callchain_sample is able to resolve callchain entries for the sample. 3. unwind__get_entries is also able to resolve callchain entries for the sample. The fix is accomplished by reversing the order in which thread__resolve_callchain_sample and unwind__get_entries are called when callchain_param.order is set to ORDER_CALLER. Unwind specific code from thread__resolve_callchain is also moved into a new static function to improve readability of the fix. How to Reproduce the Existing Bug: Modifying perf script to print call trees in the opposite order or applying the remaining patches from this series and comparing the results output from export-to-postgtresql.py are the easiest ways to see the bug, however it can still be seen in current builds using perf report. Here is how i can reproduce the bug using perf report: # perf record --call-graph=dwarf stress -c 1 -t 5 when i run this command: # perf report --call-graph=flat,0,0,callee This callchain, containing kernel (handle_irq_event, etc) and userspace samples (__libc_start_main, etc) is contained in the output, which looks correct (callee order): gen8_irq_handler handle_irq_event_percpu handle_irq_event handle_edge_irq handle_irq do_IRQ ret_from_intr __random rand 0x558f2a04dded 0x558f2a04c774 __libc_start_main 0x558f2a04dcd9 Now run this command using caller order: # perf report --call-graph=flat,0,0,caller It is expected to see the exact reverse of the above when using caller order (with "0x558f2a04dcd9" at the top and "gen8_irq_handler" at the bottom) in the output, but it is nowhere to be found. instead you see this: ret_from_intr do_IRQ handle_irq handle_edge_irq handle_irq_event handle_irq_event_percpu gen8_irq_handler 0x558f2a04dcd9 __libc_start_main 0x558f2a04c774 0x558f2a04dded rand __random Notice how internally the kernel symbols are reversed and the user space symbols are reversed, but the kernel symbols still appear above the user space symbols. if this patch is applied and perf script is re-run, you will see the expected output (with "0x558f2a04dcd9" at the top and "gen8_irq_handler" at the bottom): 0x558f2a04dcd9 __libc_start_main 0x558f2a04c774 0x558f2a04dded rand __random ret_from_intr do_IRQ handle_irq handle_edge_irq handle_irq_event handle_irq_event_percpu gen8_irq_handler Signed-off-by: Chris Phlipot <cphlipot0@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1461831551-12213-2-git-send-email-cphlipot0@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05perf hists: Move sort__has_parent into struct perf_hpp_listJiri Olsa1-1/+1
Now we have sort dimensions private for struct hists, we need to make dimension booleans hists specific as well. Moving sort__has_parent into struct perf_hpp_list. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1462276488-26683-3-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05perf machine: Introduce number of threads memberArnaldo Carvalho de Melo1-1/+6
To be used, for instance, for pre-allocating an rb_tree array for sorting by other keys besides the current pid one. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ja0ifkwue7ttjhbwijn6g6eu@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-27perf tools: Set the maximum allowed stack from /proc/sys/kernel/perf_event_max_stackArnaldo Carvalho de Melo1-3/+3
There is an upper limit to what tooling considers a valid callchain, and it was tied to the hardcoded value in the kernel, PERF_MAX_STACK_DEPTH (127), now that this can be tuned via a sysctl, make it read it and use that as the upper limit, falling back to PERF_MAX_STACK_DEPTH for kernels where this sysctl isn't present. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-yjqsd30nnkogvj5oyx9ghir9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>