[PATCH 12/13] perf bpf: Run begin/end programs

From: Jiri Olsa
Date: Mon Mar 12 2018 - 05:44:46 EST


Running begin and end programs for ebpf object.

Link: http://lkml.kernel.org/n/tip-ego7m00cr7sru8l5bjpjwwcm@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/builtin-bpf.c | 6 ++++
tools/perf/util/bpf-loader.c | 78 ++++++++++++++++++++++++++++++++++++++++++++
tools/perf/util/bpf-loader.h | 2 ++
3 files changed, 86 insertions(+)

diff --git a/tools/perf/builtin-bpf.c b/tools/perf/builtin-bpf.c
index 7065153a9577..1111e240e259 100644
--- a/tools/perf/builtin-bpf.c
+++ b/tools/perf/builtin-bpf.c
@@ -94,6 +94,10 @@ static int __cmd_bpf(int argc , const char **argv)
goto out_child;
}

+ err = bpf__run_begin(stdout);
+ if (err)
+ goto out_child;
+
if (forks) {
perf_evlist__start_workload(bpf.evlist);

@@ -115,6 +119,8 @@ static int __cmd_bpf(int argc , const char **argv)

child_pid = -1;

+ bpf__run_end(stdout);
+
out_child:
if (forks) {
if (workload_exec_errno) {
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index e59168153375..d5f9c3cd5280 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -9,6 +9,7 @@
#include <linux/bpf.h>
#include <bpf/libbpf.h>
#include <bpf/bpf.h>
+#include <bpf/interp.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/string.h>
@@ -23,6 +24,7 @@
#include "strfilter.h"
#include "llvm-utils.h"
#include "c++/clang-c.h"
+#include "bpf-userapi.h"

#define DEFINE_PRINT_FN(name, level) \
static int libbpf_##name(const char *fmt, ...) \
@@ -1547,6 +1549,82 @@ int bpf__apply_obj_config(void)
return 0;
}

+struct interp {
+ struct bpf_interp in;
+ FILE *out;
+};
+
+static int bpf_interp_call_cb(struct bpf_interp *in,
+ u64 imm, u64 *regs)
+{
+ struct interp *interp = container_of(in, struct interp, in);
+ u64 dr;
+
+ switch (imm) {
+ case BPF_FUNC_USER_bpf_map_lookup_elem:
+ dr = bpf_map_lookup_elem((int) regs[1],
+ (void *) regs[2],
+ (void *) regs[3]);
+ break;
+ case BPF_FUNC_USER_bpf_map_get_next_key:
+ dr = bpf_map_get_next_key((int) regs[1],
+ (void *) regs[2],
+ (void *) regs[3]);
+ break;
+ case BPF_FUNC_USER_print:
+ dr = fprintf(interp->out, (const char *) regs[1],
+ regs[2], regs[3], regs[4], regs[5]);
+ fflush(interp->out);
+ break;
+ default:
+ return -1;
+ break;
+ };
+
+ regs[0] = dr;
+ regs[1] = 0xdeadbeef;
+ regs[2] = 0xdeadbeef;
+ regs[3] = 0xdeadbeef;
+ regs[4] = 0xdeadbeef;
+ return 0;
+}
+
+int bpf__run_begin(FILE *out)
+{
+ struct interp interp = {
+ .in.call_cb = bpf_interp_call_cb,
+ .out = out,
+ };
+ struct bpf_object *obj, *tmp;
+ int err;
+
+ bpf_object__for_each_safe(obj, tmp) {
+ err = bpf_object__run_begin(obj, &interp.in);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+int bpf__run_end(FILE *out)
+{
+ struct interp interp = {
+ .in.call_cb = bpf_interp_call_cb,
+ .out = out,
+ };
+ struct bpf_object *obj, *tmp;
+ int err;
+
+ bpf_object__for_each_safe(obj, tmp) {
+ err = bpf_object__run_end(obj, &interp.in);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
#define bpf__for_each_map(pos, obj, objtmp) \
bpf_object__for_each_safe(obj, objtmp) \
bpf_map__for_each(pos, obj)
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index 8c2a494cab53..1ee4c3ca4927 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -87,6 +87,8 @@ int bpf__setup_stdout(struct perf_evlist *evlist);
int bpf__strerror_setup_stdout(struct perf_evlist *evlist, int err,
char *buf, size_t size);

+int bpf__run_begin(FILE *out);
+int bpf__run_end(FILE *out);
#else
#include <errno.h>

--
2.13.6