perf top: Reduce default filter threshold
On idle systems 'perf top' comes up empty by default, because the event
count filter is set to 100.
Reduce it to 5 instead.
Also add an option to limit the number of functions displayed.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/Documentation/perf_counter/builtin-top.c b/Documentation/perf_counter/builtin-top.c
index 7c907e2..3f7778b 100644
--- a/Documentation/perf_counter/builtin-top.c
+++ b/Documentation/perf_counter/builtin-top.c
@@ -64,9 +64,10 @@
static int event_count[MAX_COUNTERS];
static int fd[MAX_NR_CPUS][MAX_COUNTERS];
-static __u64 count_filter = 100;
+static __u64 count_filter = 5;
+static int print_entries = 15;
-static int target_pid = -1;
+static int target_pid = -1;
static int profile_cpu = -1;
static int nr_cpus = 0;
static unsigned int realtime_prio = 0;
@@ -254,7 +255,7 @@
struct symbol *sym = (struct symbol *)(syme + 1);
float pcnt;
- if (++printed > 18 || syme->snap_count < count_filter)
+ if (++printed > print_entries || syme->snap_count < count_filter)
continue;
pcnt = 100.0 - (100.0 * ((sum_kevents - syme->snap_count) /
@@ -650,7 +651,7 @@
"number of seconds to delay between refreshes"),
OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
"dump the symbol table used for profiling"),
- OPT_INTEGER('f', "--count-filter", &count_filter,
+ OPT_INTEGER('f', "count-filter", &count_filter,
"only display functions with more events than this"),
OPT_BOOLEAN('g', "group", &group,
"put the counters into a counter group"),
@@ -662,8 +663,10 @@
"track mmap events"),
OPT_BOOLEAN('U', "use-munmap", &use_munmap,
"track munmap events"),
- OPT_INTEGER('F', "--freq", &freq,
+ OPT_INTEGER('F', "freq", &freq,
"profile at this frequency"),
+ OPT_INTEGER('E', "entries", &print_entries,
+ "display this many functions"),
OPT_END()
};