kernel/linux.git/tools/perf/util/util.c, branch v6.19.11

perf util: Remove kernel version deadcode

2024-11-16T19:30:39+00:00

fetch_kernel_version() has been unused since Ian's 2023 commit 3d6dfae889174340 ("perf parse-events: Remove BPF event support") Remove it, and it's helpers. I noticed there are a bunch of kernel-version macros that are also unused nearby. Also remove them. Reviewed-by: Ian Rogers Signed-off-by: Dr. David Alan Gilbert Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20241116155850.113129-1-linux@treblig.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Don't set attr.exclude_guest by default

2024-10-22T16:52:11+00:00

The exclude_guest in the event attribute is to limit profiling in the host environment. But I'm not sure why we want to set it by default cause we don't care about it in most cases and I feel like it just makes new PMU implementation complicated. Of course it's useful for perf kvm command so I added the exclude_GH_default variable to preserve the old behavior for perf kvm and other commands like perf record and stat won't set the exclude bit. This is helpful for AMD IBS case since having exclude_guest bit will clear new feature bit due to the missing feature check logic. $ sysctl kernel.perf_event_paranoid kernel.perf_event_paranoid = 0 $ perf record -W -e ibs_op// -vv true 2>&1 | grep switching switching off PERF_FORMAT_LOST support switching off weight struct support switching off bpf_event switching off ksymbol switching off cloexec flag switching off mmap2 switching off exclude_guest, exclude_host Intestingly, I found it sets the exclude_bit if "u" modifier is used. I don't know why but it's neither intuitive nor consistent. Let's remove the bit there too. Reviewed-by: Ian Rogers Reviewed-by: James Clark Reviewed-by: Ravi Bangoria Acked-by: Kan Liang Cc: James Clark Cc: Atish Patra Cc: Mingwei Zhang Cc: Kajol Jain Cc: Thomas Richter Cc: Palmer Dabbelt Link: https://lore.kernel.org/r/20241016062359.264929-3-namhyung@kernel.org Signed-off-by: Namhyung Kim

perf cap: Tidy up and improve capability testing

2024-08-20T20:53:12+00:00

Remove dependence on libcap. libcap is only used to query whether a capability is supported, which is just 1 capget system call. If the capget system call fails, fall back on root permission checking. Previously if libcap fails then the permission is assumed not present which may be pessimistic/wrong. Add a used_root out argument to perf_cap__capable to say whether the fall back root check was used. This allows the correct error message, "root" vs "users with the CAP_PERFMON or CAP_SYS_ADMIN capability", to be selected. Tidy uses of perf_cap__capable so that tests aren't repeated if capget isn't supported. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Changbin Du Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Oliver Upton Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240806220614.831914-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf list: Add scandirat compatibility function

2024-02-22T17:11:41+00:00

scandirat is used during the printing of tracepoint events but may be missing from certain libcs. Add a compatibility implementation that uses the symlink of an fd in /proc as a path for the reliably present scandir. Signed-off-by: Ian Rogers Cc: James Clark Cc: Justin Stitt Cc: Bill Wendling Cc: Nick Desaulniers Cc: Yang Jihong Cc: Nathan Chancellor Cc: Kan Liang Cc: Athira Jajeev Cc: llvm@lists.linux.dev Signed-off-by: Namhyung Kim Link: https://lore.kernel.org/r/20240221034155.1500118-3-irogers@google.com

perf util: Move input_name to util

2023-04-10T22:21:31+00:00

'input_name' is the name of the input perf.data file, it is used by data convert and ui code. Move it to util to make it more consistent with other global state. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Chengdong Li Cc: Denis Nikitin Cc: Florian Fischer Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Martin Liška Cc: Mathieu Poirier Cc: Mike Leach Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Raul Silvera Cc: Ravi Bangoria Cc: Rob Herring Cc: Sean Christopherson Cc: Suzuki Poulouse Cc: Will Deacon Cc: Xing Zhengjun Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20230410162511.3055900-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Avoid warning in do_realloc_array_as_needed()

2023-04-04T12:39:56+00:00

do_realloc_array_as_needed() used memcpy() of zero size with a NULL pointer. Check the size first to avoid sanitize warning. Discovered using EXTRA_CFLAGS="-fsanitize=undefined -fsanitize=address". Reported-by: kernel test robot Signed-off-by: Adrian Hunter Acked-by: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lore.kernel.org/oe-lkp/202303061424.6ad43294-yujie.liu@intel.com Link: https://lore.kernel.org/r/20230316194156.8320-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf util: Remove weak sched_getcpu

2023-03-14T11:29:46+00:00

sched_getcpu may not be present and so a feature test and definition exist to workaround this in the build. The feature test is used to define HAVE_SCHED_GETCPU_SUPPORT and so this is sufficient to know whether the local sched_getcpu is needed and a weak symbol can be avoided. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andres Freund Cc: Ingo Molnar Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Martin Liška Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Pavithra Gurushankar Cc: Peter Zijlstra Cc: Quentin Monnet Cc: Roberto Sassu Cc: Stephane Eranian Cc: Tiezhu Yang Cc: Tom Rix Cc: Yang Jihong Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230311065753.3012826-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add reallocarray_as_needed()

2022-07-20T14:08:37+00:00

Add helper reallocarray_as_needed() to reallocate an array to a larger size and initialize the extra entries to an arbitrary value. Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220711093218.10967-24-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove also guest kcore_dir with host kcore_dir

2022-07-20T14:08:30+00:00

Copies of /proc/kallsyms, /proc/modules and an extract of /proc/kcore can be stored in the perf.data output directory under the subdirectory named kcore_dir. Guest machines will have their files also under subdirectories beginning kcore_dir__ followed by the machine pid. Remove these also when removing kcore_dir. Signed-off-by: Adrian Hunter Acked-by: Ian Rogers Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220711093218.10967-21-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Print warning when HAVE_DEBUGINFOD_SUPPORT is not set and user tries to use debuginfod support

2022-04-20T16:36:36+00:00

When one requests debuginfod, either via --debuginfod option, or with a perf-config value, complain when perf is not built with it. Signed-off-by: Martin Liška Cc: Jiri Olsa Link: http://lore.kernel.org/lkml/35bae747-3951-dc3d-a66b-abf4cebcd9cb@suse.cz Signed-off-by: Arnaldo Carvalho de Melo