From: Andi Kleen <a...@linux.intel.com> Now that the NMI watchdog runs with reference cycles, and does not conflict with TopDown anymore, we don't need to check that the NMI watchdog is off in perf stat --topdown.
Remove the code that does this and always use a group unconditionally. Signed-off-by: Andi Kleen <a...@linux.intel.com> --- tools/perf/Documentation/perf-stat.txt | 6 ------ tools/perf/arch/x86/util/Build | 1 - tools/perf/arch/x86/util/group.c | 27 --------------------------- tools/perf/builtin-stat.c | 18 +----------------- tools/perf/util/group.h | 7 ------- 5 files changed, 1 insertion(+), 58 deletions(-) delete mode 100644 tools/perf/arch/x86/util/group.c delete mode 100644 tools/perf/util/group.h diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt index d96ccd4844df..6cf4028ddc2c 100644 --- a/tools/perf/Documentation/perf-stat.txt +++ b/tools/perf/Documentation/perf-stat.txt @@ -225,12 +225,6 @@ CPU thread. Per core mode is automatically enabled and -a (global monitoring) is needed, requiring root rights or perf.perf_event_paranoid=-1. -Topdown uses the full Performance Monitoring Unit, and needs -disabling of the NMI watchdog (as root): -echo 0 > /proc/sys/kernel/nmi_watchdog -for best results. Otherwise the bottlenecks may be inconsistent -on workload with changing phases. - This enables --metric-only, unless overriden with --no-metric-only. To interpret the results it is usually needed to know on which diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build index f95e6f46ef0d..bc24b75add88 100644 --- a/tools/perf/arch/x86/util/Build +++ b/tools/perf/arch/x86/util/Build @@ -3,7 +3,6 @@ libperf-y += tsc.o libperf-y += pmu.o libperf-y += kvm-stat.o libperf-y += perf_regs.o -libperf-y += group.o libperf-$(CONFIG_DWARF) += dwarf-regs.o libperf-$(CONFIG_BPF_PROLOGUE) += dwarf-regs.o diff --git a/tools/perf/arch/x86/util/group.c b/tools/perf/arch/x86/util/group.c deleted file mode 100644 index 37f92aa39a5d..000000000000 --- a/tools/perf/arch/x86/util/group.c +++ /dev/null @@ -1,27 +0,0 @@ -#include <stdio.h> -#include "api/fs/fs.h" -#include "util/group.h" - -/* - * Check whether we can use a group for top down. - * Without a group may get bad results due to multiplexing. - */ -bool arch_topdown_check_group(bool *warn) -{ - int n; - - if (sysctl__read_int("kernel/nmi_watchdog", &n) < 0) - return false; - if (n > 0) { - *warn = true; - return false; - } - return true; -} - -void arch_topdown_group_warn(void) -{ - fprintf(stderr, - "nmi_watchdog enabled with topdown. May give wrong results.\n" - "Disable with echo 0 > /proc/sys/kernel/nmi_watchdog\n"); -} diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index dff63733dfb7..a599a78b2f22 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -59,10 +59,8 @@ #include "util/thread.h" #include "util/thread_map.h" #include "util/counts.h" -#include "util/group.h" #include "util/session.h" #include "util/tool.h" -#include "util/group.h" #include "asm/bug.h" #include <api/fs/fs.h> @@ -1861,16 +1859,6 @@ static int topdown_filter_events(const char **attr, char **str, bool use_group) return 0; } -__weak bool arch_topdown_check_group(bool *warn) -{ - *warn = false; - return false; -} - -__weak void arch_topdown_group_warn(void) -{ -} - /* * Add default attributes, if there were no attributes specified or * if -d/--detailed, -d -d or -d -d -d is used: @@ -2010,7 +1998,6 @@ static int add_default_attributes(void) if (topdown_run) { char *str = NULL; - bool warn = false; if (stat_config.aggr_mode != AGGR_GLOBAL && stat_config.aggr_mode != AGGR_CORE) { @@ -2025,14 +2012,11 @@ static int add_default_attributes(void) if (!force_metric_only) metric_only = true; - if (topdown_filter_events(topdown_attrs, &str, - arch_topdown_check_group(&warn)) < 0) { + if (topdown_filter_events(topdown_attrs, &str, true) < 0) { pr_err("Out of memory\n"); return -1; } if (topdown_attrs[0] && str) { - if (warn) - arch_topdown_group_warn(); err = parse_events(evsel_list, str, NULL); if (err) { fprintf(stderr, diff --git a/tools/perf/util/group.h b/tools/perf/util/group.h deleted file mode 100644 index 116debe7a995..000000000000 --- a/tools/perf/util/group.h +++ /dev/null @@ -1,7 +0,0 @@ -#ifndef GROUP_H -#define GROUP_H 1 - -bool arch_topdown_check_group(bool *warn); -void arch_topdown_group_warn(void); - -#endif -- 2.5.5