[tip:perf/core] perf tools: Handle kernels that don't support attr.exclude_{guest,host}

From: tip-bot for Arnaldo Carvalho de Melo
Date: Mon Mar 05 2012 - 03:40:17 EST


Commit-ID: bc76efe64533305b55d1f0834fd03414da8a12b2
Gitweb: http://git.kernel.org/tip/bc76efe64533305b55d1f0834fd03414da8a12b2
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Tue, 14 Feb 2012 14:05:30 -0200
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Sat, 3 Mar 2012 12:19:56 -0300

perf tools: Handle kernels that don't support attr.exclude_{guest,host}

Just fall back to resetting those fields, if set, warning the user that
that feature is not available.

If guest samples appear they will just be discarded because no struct
machine will be found and thus the event will be accounted as not
handled and dropped, see 0c09571.

Reported-by: Namhyung Kim <namhyung@xxxxxxxxx>
Tested-by: Joerg Roedel <joerg.roedel@xxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Joerg Roedel <joerg.roedel@xxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-vuwxig36mzprl5n7nzvnxxsh@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-record.c | 29 ++++++++++++++++++++---------
tools/perf/builtin-top.c | 23 +++++++++++++++++------
tools/perf/perf.h | 1 +
tools/perf/util/top.h | 1 +
4 files changed, 39 insertions(+), 15 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 39b6a40..227b6ae 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -204,6 +204,9 @@ static void perf_record__open(struct perf_record *rec)

if (opts->group && pos != first)
group_fd = first->fd;
+fallback_missing_features:
+ if (opts->exclude_guest_missing)
+ attr->exclude_guest = attr->exclude_host = 0;
retry_sample_id:
attr->sample_id_all = opts->sample_id_all_avail ? 1 : 0;
try_again:
@@ -217,15 +220,23 @@ try_again:
} else if (err == ENODEV && opts->cpu_list) {
die("No such device - did you specify"
" an out-of-range profile CPU?\n");
- } else if (err == EINVAL && opts->sample_id_all_avail) {
- /*
- * Old kernel, no attr->sample_id_type_all field
- */
- opts->sample_id_all_avail = false;
- if (!opts->sample_time && !opts->raw_samples && !time_needed)
- attr->sample_type &= ~PERF_SAMPLE_TIME;
-
- goto retry_sample_id;
+ } else if (err == EINVAL) {
+ if (!opts->exclude_guest_missing &&
+ (attr->exclude_guest || attr->exclude_host)) {
+ pr_debug("Old kernel, cannot exclude "
+ "guest or host samples.\n");
+ opts->exclude_guest_missing = true;
+ goto fallback_missing_features;
+ } else if (opts->sample_id_all_avail) {
+ /*
+ * Old kernel, no attr->sample_id_type_all field
+ */
+ opts->sample_id_all_avail = false;
+ if (!opts->sample_time && !opts->raw_samples && !time_needed)
+ attr->sample_type &= ~PERF_SAMPLE_TIME;
+
+ goto retry_sample_id;
+ }
}

/*
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index dd162aa..ecff312 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -857,6 +857,9 @@ static void perf_top__start_counters(struct perf_top *top)
attr->mmap = 1;
attr->comm = 1;
attr->inherit = top->inherit;
+fallback_missing_features:
+ if (top->exclude_guest_missing)
+ attr->exclude_guest = attr->exclude_host = 0;
retry_sample_id:
attr->sample_id_all = top->sample_id_all_avail ? 1 : 0;
try_again:
@@ -868,12 +871,20 @@ try_again:
if (err == EPERM || err == EACCES) {
ui__error_paranoid();
goto out_err;
- } else if (err == EINVAL && top->sample_id_all_avail) {
- /*
- * Old kernel, no attr->sample_id_type_all field
- */
- top->sample_id_all_avail = false;
- goto retry_sample_id;
+ } else if (err == EINVAL) {
+ if (!top->exclude_guest_missing &&
+ (attr->exclude_guest || attr->exclude_host)) {
+ pr_debug("Old kernel, cannot exclude "
+ "guest or host samples.\n");
+ top->exclude_guest_missing = true;
+ goto fallback_missing_features;
+ } else if (top->sample_id_all_avail) {
+ /*
+ * Old kernel, no attr->sample_id_type_all field
+ */
+ top->sample_id_all_avail = false;
+ goto retry_sample_id;
+ }
}
/*
* If it's cycles then fall back to hrtimer
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index 64f8bee..16e7d20 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -199,6 +199,7 @@ struct perf_record_opts {
bool sample_address;
bool sample_time;
bool sample_id_all_avail;
+ bool exclude_guest_missing;
bool system_wide;
bool period;
unsigned int freq;
diff --git a/tools/perf/util/top.h b/tools/perf/util/top.h
index a248f3c..f2eab81 100644
--- a/tools/perf/util/top.h
+++ b/tools/perf/util/top.h
@@ -34,6 +34,7 @@ struct perf_top {
bool inherit;
bool group;
bool sample_id_all_avail;
+ bool exclude_guest_missing;
bool dump_symtab;
const char *cpu_list;
struct hist_entry *sym_filter_entry;
--
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