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2024-04-26perf test: Reintroduce -p/--parallel and make -S/--sequential the defaultArnaldo Carvalho de Melo
We can't default to doing parallel tests as there are tests that compete for the same resources and thus clash, for instance tests that put in place 'perf probe' probes, that clean the probes without regard to other tests needs, ARM64 coresight tests, Intel PT ones, etc. So reintroduce --p/--parallel and make -S/--sequential the default. We need to come up with infrastructure that state which tests can't run in parallel because they need exclusive access to some resource, something as simple as "probes" that would then avoid 'perf probe' tests from running while other such test is running, or make the tests more resilient, till then we can't use parallel mode as default. While at it, document all these options in the 'perf test' man page. Reported-by: Adrian Hunter <adrian.hunter@intel.com> Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Reported-by: James Clark <james.clark@arm.com> Reviewed-by: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/lkml/Ziwm18BqIn_vc1vn@x1 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-01-22perf test: Add Symbols testAdrian Hunter
Add a test to check function symbols do not overlap and are not zero length. The main motivation for the test is to make it easier to review changes to PLT symbol synthesis i.e. changes to dso__synthesize_plt_symbols(). By default the test uses the perf executable as a test DSO, but a specific DSO can be specified via a new perf test option "--dso". The test is useful in the following ways: - Any DSO can be tested, even ones that do not run on the current architecture. For example, using cross-compiled DSOs to see how well perf handles different architectures. - With verbose > 1 (e.g. -vv), all the symbols are printed, which makes it easier to see issues. - perf removes duplicate symbols and expands zero-length symbols to reach the next symbol, however that is done before adding synthesized symbols, so the test is checking those also. Example: $ perf test -v Symbols 74: Symbols : --- start --- test child forked, pid 154918 Testing /home/user/bin/perf Overlapping symbols: 7d000-7f3a0 g _init 7d030-7d040 g __printf_chk@plt test child finished with -1 ---- end ---- Symbols: FAILED! Note the test fails because perf expands the _init symbol over the PLT because there are no PLT symbols at that point, but then dso__synthesize_plt_symbols() creates them. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20230120123456.12449-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-30perf test: Add -F/--dont-fork optionJiri Olsa
Adding -F/--dont-fork option to bypass forking for each test. It's useful for debugging test. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Nilay Vaish <nilayvaish@gmail.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/1467113345-12669-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-15perf Documentation: Fix typos in perf/DocumentationMasanari Iida
This patch fix spelling typos found in tool/perf/Documentation. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Randy Dunlap <rdunlap@infradead.org> Link: http://lkml.kernel.org/r/1410275930-17207-1-git-send-email-standby24x7@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-01-24perf test: Allow skipping testsArnaldo Carvalho de Melo
Sometimes a test is problematic for some reason and one wants to skip it, for instance: [root@sandy ~]# perf test 1: vmlinux symtab matches kallsyms : Ok 2: detect open syscall event : Ok 3: detect open syscall event on all cpus : Ok 4: read samples using the mmap interface : Ok 5: parse events tests : Warning: bad op token { Warning: bad op token { Warning: bad op token { Warning: bad op token { Warning: bad op token { Warning: function is_writable_pte not defined Segmentation fault (core dumped) So now we can use -s/--skip while the problematic tests are being fixed, allowing us to test all the other entries: [root@sandy ~]# perf test -s 5 1: vmlinux symtab matches kallsyms : Ok 2: detect open syscall event : Ok 3: detect open syscall event on all cpus : Ok 4: read samples using the mmap interface : Ok 5: parse events tests : Skip (user override) 6: x86 rdpmc test : Ok 7: Validate PERF_RECORD_* events & perf_sample fields : Ok 8: Test perf pmu format parsing : Ok 9: Test dso data interface : Ok 10: roundtrip evsel->name check : Ok 11: Check parsing of sched tracepoints fields : Ok 12: Generate and check syscalls:sys_enter_open event fields: Ok 13: struct perf_event_attr setup : Ok 14: Test matching and linking mutliple hists : Ok 15: Try 'use perf' in python, checking link problems : Ok [root@sandy ~]# Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-klzd8p57jzdryafqkmlppcb1@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-11-29perf test: Allow running just a subset of the available testsArnaldo Carvalho de Melo
To obtain a list of available tests: [root@emilia linux]# perf test list 1: vmlinux symtab matches kallsyms 2: detect open syscall event 3: detect open syscall event on all cpus 4: read samples using the mmap interface 5: parse events tests [root@emilia linux]# To list just a subset: [root@emilia linux]# perf test list syscall 2: detect open syscall event 3: detect open syscall event on all cpus [root@emilia linux]# To run a subset: [root@emilia linux]# perf test detect 2: detect open syscall event: Ok 3: detect open syscall event on all cpus: Ok [root@emilia linux]# Specific tests can be chosen by number: [root@emilia linux]# perf test 1 3 parse 1: vmlinux symtab matches kallsyms: Ok 3: detect open syscall event on all cpus: Ok 5: parse events tests: Ok [root@emilia linux]# Now to write more tests! Suggested-by: Peter Zijlstra <peterz@infradead.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-nqec2145qfxdgimux28aw7v8@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-12-01perf test: Fix spelling mistake in documentationShawn Bohrer
Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1291168642-11402-13-git-send-email-shawn.bohrer@gmail.com> Signed-off-by: Shawn Bohrer <shawn.bohrer@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-29perf test: Initial regression testing commandArnaldo Carvalho de Melo
First an example with the first internal test: [acme@doppio linux-2.6-tip]$ perf test 1: vmlinux symtab matches kallsyms: Ok So it run just one test, that is "vmlinux symtab matches kallsyms", and it was successful. If we run it in verbose mode, we'll see details about errors and extra warnings for non-fatal problems: [acme@doppio linux-2.6-tip]$ perf test -v 1: vmlinux symtab matches kallsyms: --- start --- Looking at the vmlinux_path (5 entries long) No build_id in vmlinux, ignoring it No build_id in /boot/vmlinux, ignoring it No build_id in /boot/vmlinux-2.6.34-rc4-tip+, ignoring it Using /lib/modules/2.6.34-rc4-tip+/build/vmlinux for symbols Maps only in vmlinux: ffffffff81cb81b1-ffffffff81e1149b 0 [kernel].init.text ffffffff81e1149c-ffffffff9fffffff 0 [kernel].exit.text ffffffffff600000-ffffffffff6000ff 0 [kernel].vsyscall_0 ffffffffff600100-ffffffffff6003ff 0 [kernel].vsyscall_fn ffffffffff600400-ffffffffff6007ff 0 [kernel].vsyscall_1 ffffffffff600800-ffffffffffffffff 0 [kernel].vsyscall_2 Maps in vmlinux with a different name in kallsyms: ffffffffff600000-ffffffffff6000ff 0 [kernel].vsyscall_0 in kallsyms as [kernel].0 ffffffffff600100-ffffffffff6003ff 0 [kernel].vsyscall_fn in kallsyms as: *ffffffffff600100-ffffffffff60012f 0 [kernel].2 ffffffffff600400-ffffffffff6007ff 0 [kernel].vsyscall_1 in kallsyms as [kernel].6 ffffffffff600800-ffffffffffffffff 0 [kernel].vsyscall_2 in kallsyms as [kernel].8 Maps only in kallsyms: ffffffffff600130-ffffffffff6003ff 0 [kernel].4 ---- end ---- vmlinux symtab matches kallsyms: Ok [acme@doppio linux-2.6-tip]$ In the above case we only know the name of the non contiguous kernel ranges in the address space when reading the symbol information from the ELF symtab in vmlinux. The /proc/kallsyms file lack this, we only notice they are separate because there are modules after the kernel and after that more kernel functions, so we need to have a module rbtree backed by the module .ko path to get symtabs in the vmlinux case. The tool uses it to match by address to emit appropriate warning, but don't considers this fatal. The .init.text and .exit.text ines, of course, aren't in kallsyms, so I left these cases just as extra info in verbose mode. The end of the sections also aren't in kallsyms, so we the symbols layer does another pass and sets the end addresses as the next map start minus one, which sometimes pads, causing harmless mismatches. But at least the symbols match, tested it by copying /proc/kallsyms to /tmp/kallsyms and doing changes to see if they were detected. This first test also should serve as a first stab at documenting the symbol library by providing a self contained example that exercises it together with comments about what is being done. More tests to check if actions done on a monitored app, like doing mmaps, etc, makes the kernel generate the expected events should be added next. Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>