From 5f6f55809758e106eca72c6e01402c8080a88ee8 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Fri, 27 May 2011 11:53:28 -0300 Subject: [PATCH] perf top: Handle kptr_restrict Reported-by: Ingo Molnar Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/n/tip-cyl5zmi1nu35vyu7l5im2pyv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-top.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 375ed160d936..472f62790022 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -80,6 +80,7 @@ static bool use_tui, use_stdio; static int default_interval = 0; +static bool kptr_restrict_warned; static bool inherit = false; static int realtime_prio = 0; static bool group = false; @@ -738,6 +739,20 @@ static void perf_event__process_sample(const union perf_event *event, al.filtered) return; + if (!kptr_restrict_warned && + symbol_conf.kptr_restrict && + al.cpumode == PERF_RECORD_MISC_KERNEL) { + ui__warning( +"Kernel address maps (/proc/{kallsyms,modules}) are restricted.\n\n" +"Check /proc/sys/kernel/kptr_restrict.\n\n" +"Kernel%s samples will not be resolved.\n", + !RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION]) ? + " modules" : ""); + if (use_browser <= 0) + sleep(5); + kptr_restrict_warned = true; + } + if (al.sym == NULL) { /* * As we do lazy loading of symtabs we only will know if the