[PATCH 16/35] perf dlfilter: Add machine_pid and vcpu

Adrian Hunter
2022-07-11T10:12:12Z

Add machine_pid and vcpu to struct perf_dlfilter_sample. The 'size' can be
used to determine if the values are present, however machine_pid is zero if
unused in any case. vcpu should be ignored if machine_pid is zero.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
tools/perf/Documentation/perf-dlfilter.txt | 22 ++++++++++++++++++++++
tools/perf/include/perf/perf_dlfilter.h | 8 ++++++++
tools/perf/util/dlfilter.c | 2 ++
3 files changed, 32 insertions(+)

diff --git a/tools/perf/Documentation/perf-dlfilter.txt b/tools/perf/Documentation/perf-dlfilter.txt
index 594f5a5a0c9e..fb22e3b31dc5 100644
--- a/tools/perf/Documentation/perf-dlfilter.txt
+++ b/tools/perf/Documentation/perf-dlfilter.txt
@@ -107,9 +107,31 @@ struct perf_dlfilter_sample {
__u64 raw_callchain_nr; /* Number of raw_callchain entries */
const __u64 *raw_callchain; /* Refer <linux/perf_event.h> */
const char *event;
+ __s32 machine_pid;
+ __s32 vcpu;
};
----

+Note: 'machine_pid' and 'vcpu' are not original members, but were added together later.
+'size' can be used to determine their presence at run time.
+PERF_DLFILTER_HAS_MACHINE_PID will be defined if they are present at compile time.
+For example:
+[source,c]
+----
+#include <perf/perf_dlfilter.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+static inline bool have_machine_pid(const struct perf_dlfilter_sample *sample)
+{
+#ifdef PERF_DLFILTER_HAS_MACHINE_PID
+ return sample->size >= offsetof(struct perf_dlfilter_sample, vcpu) + sizeof(sample->vcpu);
+#else
+ return false;
+#endif
+}
+----
+
The perf_dlfilter_fns structure
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

diff --git a/tools/perf/include/perf/perf_dlfilter.h b/tools/perf/include/perf/perf_dlfilter.h
index 3eef03d661b4..a26e2f129f83 100644
--- a/tools/perf/include/perf/perf_dlfilter.h
+++ b/tools/perf/include/perf/perf_dlfilter.h
@@ -9,6 +9,12 @@
#include <linux/perf_event.h>
#include <linux/types.h>

+/*
+ * The following macro can be used to determine if this header defines
+ * perf_dlfilter_sample machine_pid and vcpu.
+ */
+#define PERF_DLFILTER_HAS_MACHINE_PID
+
/* Definitions for perf_dlfilter_sample flags */
enum {
PERF_DLFILTER_FLAG_BRANCH = 1ULL << 0,
@@ -62,6 +68,8 @@ struct perf_dlfilter_sample {
__u64 raw_callchain_nr; /* Number of raw_callchain entries */
const __u64 *raw_callchain; /* Refer <linux/perf_event.h> */
const char *event;
+ __s32 machine_pid;
+ __s32 vcpu;
};

/*
diff --git a/tools/perf/util/dlfilter.c b/tools/perf/util/dlfilter.c
index db964d5a52af..54e4d4495e00 100644
--- a/tools/perf/util/dlfilter.c
+++ b/tools/perf/util/dlfilter.c
@@ -495,6 +495,8 @@ int dlfilter__do_filter_event(struct dlfilter *d,
ASSIGN(misc);
ASSIGN(raw_size);
ASSIGN(raw_data);
+ ASSIGN(machine_pid);
+ ASSIGN(vcpu);

if (sample->branch_stack) {
d_sample.brstack_nr = sample->branch_stack->nr;
--
2.25.1