scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 258 insertions, 0 deletions

diff --git a/tools/bpf/bpftool/perf.c b/tools/bpf/bpftool/perf.c
new file mode 100644
index 000000000..80de2874d
--- /dev/null
+++ b/tools/bpf/bpftool/perf.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+// Copyright (C) 2018 Facebook
+// Author: Yonghong Song <yhs@fb.com>
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <dirent.h>
+
+#include <bpf/bpf.h>
+
+#include "main.h"
+
+/* 0: undecided, 1: supported, 2: not supported */
+static int perf_query_supported;
+static bool has_perf_query_support(void)
+{
+	__u64 probe_offset, probe_addr;
+	__u32 len, prog_id, fd_type;
+	char buf[256];
+	int fd;
+
+	if (perf_query_supported)
+		goto out;
+
+	fd = open("/", O_RDONLY);
+	if (fd < 0) {
+		p_err("perf_query_support: cannot open directory \"/\" (%s)",
+		      strerror(errno));
+		goto out;
+	}
+
+	/* the following query will fail as no bpf attachment,
+	 * the expected errno is ENOTSUPP
+	 */
+	errno = 0;
+	len = sizeof(buf);
+	bpf_task_fd_query(getpid(), fd, 0, buf, &len, &prog_id,
+			  &fd_type, &probe_offset, &probe_addr);
+
+	if (errno == 524 /* ENOTSUPP */) {
+		perf_query_supported = 1;
+		goto close_fd;
+	}
+
+	perf_query_supported = 2;
+	p_err("perf_query_support: %s", strerror(errno));
+	fprintf(stderr,
+		"HINT: non root or kernel doesn't support TASK_FD_QUERY\n");
+
+close_fd:
+	close(fd);
+out:
+	return perf_query_supported == 1;
+}
+
+static void print_perf_json(int pid, int fd, __u32 prog_id, __u32 fd_type,
+			    char *buf, __u64 probe_offset, __u64 probe_addr)
+{
+	jsonw_start_object(json_wtr);
+	jsonw_int_field(json_wtr, "pid", pid);
+	jsonw_int_field(json_wtr, "fd", fd);
+	jsonw_uint_field(json_wtr, "prog_id", prog_id);
+	switch (fd_type) {
+	case BPF_FD_TYPE_RAW_TRACEPOINT:
+		jsonw_string_field(json_wtr, "fd_type", "raw_tracepoint");
+		jsonw_string_field(json_wtr, "tracepoint", buf);
+		break;
+	case BPF_FD_TYPE_TRACEPOINT:
+		jsonw_string_field(json_wtr, "fd_type", "tracepoint");
+		jsonw_string_field(json_wtr, "tracepoint", buf);
+		break;
+	case BPF_FD_TYPE_KPROBE:
+		jsonw_string_field(json_wtr, "fd_type", "kprobe");
+		if (buf[0] != '\0') {
+			jsonw_string_field(json_wtr, "func", buf);
+			jsonw_lluint_field(json_wtr, "offset", probe_offset);
+		} else {
+			jsonw_lluint_field(json_wtr, "addr", probe_addr);
+		}
+		break;
+	case BPF_FD_TYPE_KRETPROBE:
+		jsonw_string_field(json_wtr, "fd_type", "kretprobe");
+		if (buf[0] != '\0') {
+			jsonw_string_field(json_wtr, "func", buf);
+			jsonw_lluint_field(json_wtr, "offset", probe_offset);
+		} else {
+			jsonw_lluint_field(json_wtr, "addr", probe_addr);
+		}
+		break;
+	case BPF_FD_TYPE_UPROBE:
+		jsonw_string_field(json_wtr, "fd_type", "uprobe");
+		jsonw_string_field(json_wtr, "filename", buf);
+		jsonw_lluint_field(json_wtr, "offset", probe_offset);
+		break;
+	case BPF_FD_TYPE_URETPROBE:
+		jsonw_string_field(json_wtr, "fd_type", "uretprobe");
+		jsonw_string_field(json_wtr, "filename", buf);
+		jsonw_lluint_field(json_wtr, "offset", probe_offset);
+		break;
+	default:
+		break;
+	}
+	jsonw_end_object(json_wtr);
+}
+
+static void print_perf_plain(int pid, int fd, __u32 prog_id, __u32 fd_type,
+			     char *buf, __u64 probe_offset, __u64 probe_addr)
+{
+	printf("pid %d  fd %d: prog_id %u  ", pid, fd, prog_id);
+	switch (fd_type) {
+	case BPF_FD_TYPE_RAW_TRACEPOINT:
+		printf("raw_tracepoint  %s\n", buf);
+		break;
+	case BPF_FD_TYPE_TRACEPOINT:
+		printf("tracepoint  %s\n", buf);
+		break;
+	case BPF_FD_TYPE_KPROBE:
+		if (buf[0] != '\0')
+			printf("kprobe  func %s  offset %llu\n", buf,
+			       probe_offset);
+		else
+			printf("kprobe  addr %llu\n", probe_addr);
+		break;
+	case BPF_FD_TYPE_KRETPROBE:
+		if (buf[0] != '\0')
+			printf("kretprobe  func %s  offset %llu\n", buf,
+			       probe_offset);
+		else
+			printf("kretprobe  addr %llu\n", probe_addr);
+		break;
+	case BPF_FD_TYPE_UPROBE:
+		printf("uprobe  filename %s  offset %llu\n", buf, probe_offset);
+		break;
+	case BPF_FD_TYPE_URETPROBE:
+		printf("uretprobe  filename %s  offset %llu\n", buf,
+		       probe_offset);
+		break;
+	default:
+		break;
+	}
+}
+
+static int show_proc(void)
+{
+	struct dirent *proc_de, *pid_fd_de;
+	__u64 probe_offset, probe_addr;
+	__u32 len, prog_id, fd_type;
+	DIR *proc, *pid_fd;
+	int err, pid, fd;
+	const char *pch;
+	char buf[4096];
+
+	proc = opendir("/proc");
+	if (!proc)
+		return -1;
+
+	while ((proc_de = readdir(proc))) {
+		pid = 0;
+		pch = proc_de->d_name;
+
+		/* pid should be all numbers */
+		while (isdigit(*pch)) {
+			pid = pid * 10 + *pch - '0';
+			pch++;
+		}
+		if (*pch != '\0')
+			continue;
+
+		err = snprintf(buf, sizeof(buf), "/proc/%s/fd", proc_de->d_name);
+		if (err < 0 || err >= (int)sizeof(buf))
+			continue;
+
+		pid_fd = opendir(buf);
+		if (!pid_fd)
+			continue;
+
+		while ((pid_fd_de = readdir(pid_fd))) {
+			fd = 0;
+			pch = pid_fd_de->d_name;
+
+			/* fd should be all numbers */
+			while (isdigit(*pch)) {
+				fd = fd * 10 + *pch - '0';
+				pch++;
+			}
+			if (*pch != '\0')
+				continue;
+
+			/* query (pid, fd) for potential perf events */
+			len = sizeof(buf);
+			err = bpf_task_fd_query(pid, fd, 0, buf, &len,
+						&prog_id, &fd_type,
+						&probe_offset, &probe_addr);
+			if (err < 0)
+				continue;
+
+			if (json_output)
+				print_perf_json(pid, fd, prog_id, fd_type, buf,
+						probe_offset, probe_addr);
+			else
+				print_perf_plain(pid, fd, prog_id, fd_type, buf,
+						 probe_offset, probe_addr);
+		}
+		closedir(pid_fd);
+	}
+	closedir(proc);
+	return 0;
+}
+
+static int do_show(int argc, char **argv)
+{
+	int err;
+
+	if (!has_perf_query_support())
+		return -1;
+
+	if (json_output)
+		jsonw_start_array(json_wtr);
+	err = show_proc();
+	if (json_output)
+		jsonw_end_array(json_wtr);
+
+	return err;
+}
+
+static int do_help(int argc, char **argv)
+{
+	fprintf(stderr,
+		"Usage: %1$s %2$s { show | list }\n"
+		"       %1$s %2$s help\n"
+		"\n"
+		"       " HELP_SPEC_OPTIONS " }\n"
+		"",
+		bin_name, argv[-2]);
+
+	return 0;
+}
+
+static const struct cmd cmds[] = {
+	{ "show",	do_show },
+	{ "list",	do_show },
+	{ "help",	do_help },
+	{ 0 }
+};
+
+int do_perf(int argc, char **argv)
+{
+	return cmd_select(cmds, argc, argv, do_help);
+}