kernel.git/tools/perf/util/parse-events.c, branch linux-4.4.y

perf tools: Fix snprint warnings for gcc 8

2020-07-31T14:43:17Z

commit 77f18153c080855e1c3fb520ca31a4e61530121d upstream. [Add an additional sprintf replacement in tools/perf/builtin-script.c] With gcc 8 we get new set of snprintf() warnings that breaks the compilation, one example: tests/mem.c: In function ‘check’: tests/mem.c:19:48: error: ‘%s’ directive output may be truncated writing \ up to 99 bytes into a region of size 89 [-Werror=format-truncation=] snprintf(failure, sizeof failure, "unexpected %s", out); The gcc docs says: To avoid the warning either use a bigger buffer or handle the function's return value which indicates whether or not its output has been truncated. Given that all these warnings are harmless, because the code either properly fails due to uncomplete file path or we don't care for truncated output at all, I'm changing all those snprintf() calls to scnprintf(), which actually 'checks' for the snprint return value so the gcc stays silent. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: David Ahern Cc: Josh Poimboeuf Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Sergey Senozhatsky Link: http://lkml.kernel.org/r/20180319082902.4518-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf parse-events: Fix unchecked usage of strncpy()

2019-01-26T08:42:54Z

[ Upstream commit bd8d57fb7e25e9fcf67a9eef5fa13aabe2016e07 ] The strncpy() function may leave the destination string buffer unterminated, better use strlcpy() that we have a __weak fallback implementation for systems without it. This fixes this warning on an Alpine Linux Edge system with gcc 8.2: util/parse-events.c: In function 'print_symbol_events': util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation] strncpy(name, syms->symbol, MAX_NAME_LEN); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In function 'print_symbol_events.constprop', inlined from 'print_events' at util/parse-events.c:2508:2: util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation] strncpy(name, syms->symbol, MAX_NAME_LEN); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In function 'print_symbol_events.constprop', inlined from 'print_events' at util/parse-events.c:2511:2: util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation] strncpy(name, syms->symbol, MAX_NAME_LEN); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Fixes: 947b4ad1d198 ("perf list: Fix max event string size") Link: https://lkml.kernel.org/n/tip-b663e33bm6x8hrkie4uxh7u2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf tools: Only increase index if perf_evsel__new_idx() succeeds

2017-11-08T09:06:29Z

[ Upstream commit 75fc5ae5cc53fff71041ecadeb3354a2b4c9fe42 ] Signed-off-by: Taeung Song Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1485952447-7013-2-git-send-email-treeze.taeung@gmail.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

perf tools: Use readdir() instead of deprecated readdir_r() again

2017-07-15T09:57:49Z

commit 22a9f41b555673e7499b97acf3ffb07bf0af31ad upstream. The readdir() function is thread safe as long as just one thread uses a DIR, which is the case when parsing tracepoint event definitions, to avoid breaking the build with glibc-2.23.90 (upcoming 2.24), use it instead of readdir_r(). See: http://man7.org/linux/man-pages/man3/readdir.3.html "However, in modern implementations (including the glibc implementation), concurrent calls to readdir() that specify different directory streams are thread-safe. In cases where multiple threads must read from the same directory stream, using readdir() with external synchronization is still preferable to the use of the deprecated readdir_r(3) function." Noticed while building on a Fedora Rawhide docker container. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-wddn49r6bz6wq4ee3dxbl7lo@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf tools: Fix checking asprintf return value

2016-04-12T16:08:35Z

commit 26dee028d365fbc0e3326606a8520260b4462381 upstream. According to man pages, asprintf returns -1 when failure. This patch fixes two incorrect return value checker. Signed-off-by: Wang Nan Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: Brendan Gregg Cc: Cody P Schafer Cc: He Kuang Cc: Jeremie Galarneau Cc: Jiri Olsa Cc: Kirill Smelkov Cc: Li Zefan Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Fixes: ffeb883e5662 ("perf tools: Show proper error message for wrong terms of hw/sw events") Link: http://lkml.kernel.org/r/1455882283-79592-5-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf tools: tracepoint_error() can receive e=NULL, robustify it

2016-02-25T20:01:16Z

commit ec183d22cc284a7a1e17f0341219d8ec8ca070cc upstream. Fixes segmentation fault using, for instance: (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64 [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 (gdb) bt #0 0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 #1 0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:433 #2 0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:498 #3 0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:936 #4 0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391 #5 0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361 #6 0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401 #7 0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253 #8 0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364 #9 0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 ) at arch/x86/util/intel-pt.c:664 #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 ) at util/auxtrace.c:539 #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264 #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 , argc=5, argv=0x7fffffffde60) at perf.c:390 #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451 #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495 #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618 (gdb) Intel PT attempts to find the sched:sched_switch tracepoint but that seg faults if tracefs is not readable, because the error reporting structure is null, as errors are not reported when automatically adding tracepoints. Fix by checking before using. Committer note: This doesn't take place in a kernel that supports perf_event_attr.context_switch, that is the default way that will be used for tracking context switches, only in older kernels, like 4.2, in a machine with Intel PT (e.g. Broadwell) for non-priviledged users. Further info from a similar patch by Wang: The error is in tracepoint_error: it assumes the 'e' parameter is valid. However, there are many situation a parse_event() can be called without parse_events_error. See result of $ grep 'parse_events(.*NULL)' ./tools/perf/ -r' Signed-off-by: Adrian Hunter Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Tong Zhang Cc: Wang Nan Fixes: 196581717d85 ("perf tools: Enhance parsing events tracepoint error output") Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf list: Robustify event printing routine

2015-12-16T19:43:10Z

When a43eec304259 ("bpf: introduce bpf_perf_event_output() helper") added PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw array that wasn't initialized, thus set to NULL, fix print_symbol_events() to check for that case so that we don't crash if this happens again. (gdb) bt #0 __match_glob (ignore_space=false, pat=, str=) at util/string.c:198 #1 strglobmatch (str=, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252 #2 0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 , max=11, name_only=false, event_glob=0x7fffffffe61d "stall") at util/parse-events.c:1615 #3 print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675 #4 0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=) at builtin-list.c:68 #5 0x00000000004788a5 in run_builtin (p=p@entry=0x871758 , argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370 #6 0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429 #7 run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473 #8 main (argc=2, argv=0x7fffffffe390) at perf.c:588 (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT] $4 = {symbol = 0x0, alias = 0x0} (gdb) A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-57wysblcjfrseb0zg5u7ek10@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf list: Add support for PERF_COUNT_SW_BPF_OUT

2015-12-16T19:43:10Z

When PERF_COUNT_SW_BPF_OUTPUT was added to the kernel we should've added it to tools/perf, where it is used just to list events. This ended up causing a segfault in commands like "perf list stall". Fix it by adding that new software counter. A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-uya354upi3eprsey6mi5962d@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Improve BPF related error messages

2015-11-06T20:14:20Z

A series of bpf loader related error codes were introduced to help error reporting. Functions were improved to return these new error codes. Functions which return pointers were adjusted to encode error codes into return value using the ERR_PTR() interface. bpf_loader_strerror() was improved to convert these error messages to strings. It checks the error codes and calls libbpf_strerror() and strerror_r() accordingly, so caller don't need to consider checking the range of the error code. In bpf__strerror_load(), print kernel version of running kernel and the object's 'version' section to notify user how to fix his/her program. v1 -> v2: Use macro for error code. Fetch error message based on array index, eliminate for-loop. Print version strings. Before: # perf record -e ./test_kversion_nomatch_program.o sleep 1 event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP After: # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ 'version' (4.4.0) doesn't match running kernel (4.3.0) SKIP Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446818289-87444-1-git-send-email-wangnan0@huawei.com [ Add 'static inline' to bpf__strerror_prepare_load() when LIBBPF is disabled ] Signed-off-by: Arnaldo Carvalho de Melo

bpf tools: Improve libbpf error reporting

2015-11-06T18:52:41Z

In this patch, a series of libbpf specific error numbers and libbpf_strerror() are introduced to help reporting errors. Functions are updated to pass correct the error number through the CHECK_ERR() macro. All users of bpf_object__open{_buffer}() and bpf_program__title() in perf are modified accordingly. In addition, due to the error codes changing, bpf__strerror_load() is also modified to use them. bpf__strerror_head() is also changed accordingly so it can parse libbpf errors. bpf_loader_strerror() is introduced for that purpose, and will be improved by the following patch. load_program() is improved not to dump log buffer if it is empty. log buffer is also used to deduce whether the error was caused by an invalid program or other problem. v1 -> v2: - Using macro for error code. - Fetch error message based on array index, eliminate for-loop. - Use log buffer to detect the reason of failure. 3 new error code are introduced to replace LIBBPF_ERRNO__LOAD. In v1: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_kversion_nomatch_program.o ls event syntax error: './test_kversion_nomatch_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP # perf record -e ./test_big_program.o ls event syntax error: './test_big_program.o' \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object SKIP In v2: # perf record -e ./test_ill_program.o ls event syntax error: './test_ill_program.o' \___ Kernel verifier blocks program loading SKIP # perf record -e ./test_kversion_nomatch_program.o event syntax error: './test_kversion_nomatch_program.o' \___ Incorrect kernel version SKIP (Will be further improved by following patches) # perf record -e ./test_big_program.o event syntax error: './test_big_program.o' \___ Program too big SKIP Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1446817783-86722-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo