From c286c419c784c238cd699be37fec7a9acc30d89f Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 28 Mar 2011 09:50:11 -0300 Subject: [PATCH] perf tools: Fixup exit path when not able to open events We have to deal with the TUI mode in perf top, so that we don't end up with a garbled screen when, say, a non root user on a machine with a paranoid setting (the default) tries to use 'perf top'. Introduce a ui__warning_paranoid() routine shared by top and record that tells the user the valid values for /proc/sys/kernel/perf_event_paranoid. Cc: David Ahern Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi LKML-Reference: Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 9 ++++----- tools/perf/builtin-top.c | 38 +++++++++++++++++++++++-------------- tools/perf/util/debug.c | 10 ++++++++++ tools/perf/util/debug.h | 1 + 4 files changed, 39 insertions(+), 19 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 6febcc168a8c..623695e18254 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -275,11 +275,10 @@ try_again: !no_inherit) < 0) { int err = errno; - if (err == EPERM || err == EACCES) - die("Permission error - are you root?\n" - "\t Consider tweaking" - " /proc/sys/kernel/perf_event_paranoid.\n"); - else if (err == ENODEV && cpu_list) { + if (err == EPERM || err == EACCES) { + ui__warning_paranoid(); + exit(EXIT_FAILURE); + } else if (err == ENODEV && cpu_list) { die("No such device - did you specify" " an out-of-range profile CPU?\n"); } else if (err == EINVAL && sample_id_all_avail) { diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 676b4fb0070f..935fc4fd878e 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -850,10 +850,10 @@ try_again: top.evlist->threads, group, inherit) < 0) { int err = errno; - if (err == EPERM || err == EACCES) - die("Permission error - are you root?\n" - "\t Consider tweaking" - " /proc/sys/kernel/perf_event_paranoid.\n"); + if (err == EPERM || err == EACCES) { + ui__warning_paranoid(); + goto out_err; + } /* * If it's cycles then fall back to hrtimer * based cpu-clock-tick sw counter, which @@ -861,25 +861,35 @@ try_again: */ if (attr->type == PERF_TYPE_HARDWARE && attr->config == PERF_COUNT_HW_CPU_CYCLES) { - if (verbose) - warning(" ... trying to fall back to cpu-clock-ticks\n"); + ui__warning("Cycles event not supported,\n" + "trying to fall back to cpu-clock-ticks\n"); attr->type = PERF_TYPE_SOFTWARE; attr->config = PERF_COUNT_SW_CPU_CLOCK; goto try_again; } - printf("\n"); - error("sys_perf_event_open() syscall returned with %d " - "(%s). /bin/dmesg may provide additional information.\n", - err, strerror(err)); - die("No CONFIG_PERF_EVENTS=y kernel support configured?\n"); - exit(-1); + + ui__warning("The sys_perf_event_open() syscall " + "returned with %d (%s). /bin/dmesg " + "may provide additional information.\n" + "No CONFIG_PERF_EVENTS=y kernel support " + "configured?\n", err, strerror(err)); + goto out_err; } } - if (perf_evlist__mmap(evlist, mmap_pages, false) < 0) - die("failed to mmap with %d (%s)\n", errno, strerror(errno)); + if (perf_evlist__mmap(evlist, mmap_pages, false) < 0) { + ui__warning("Failed to mmap with %d (%s)\n", + errno, strerror(errno)); + goto out_err; + } + + return; + +out_err: + exit_browser(0); + exit(0); } static int __cmd_top(void) diff --git a/tools/perf/util/debug.c b/tools/perf/util/debug.c index d4536a9e0d8c..155749d74350 100644 --- a/tools/perf/util/debug.c +++ b/tools/perf/util/debug.c @@ -57,6 +57,16 @@ void ui__warning(const char *format, ...) } #endif +void ui__warning_paranoid(void) +{ + ui__warning("Permission error - are you root?\n" + "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n" + " -1 - Not paranoid at all\n" + " 0 - Disallow raw tracepoint access for unpriv\n" + " 1 - Disallow cpu events for unpriv\n" + " 2 - Disallow kernel profiling for unpriv\n"); +} + void trace_event(union perf_event *event) { unsigned char *raw_event = (void *)event; diff --git a/tools/perf/util/debug.h b/tools/perf/util/debug.h index 93516cf4682c..fd53db47e3de 100644 --- a/tools/perf/util/debug.h +++ b/tools/perf/util/debug.h @@ -36,5 +36,6 @@ int ui_helpline__show_help(const char *format, va_list ap); #endif void ui__warning(const char *format, ...) __attribute__((format(printf, 1, 2))); +void ui__warning_paranoid(void); #endif /* __PERF_DEBUG_H */ -- 2.39.2