1 files changed, 308 insertions, 0 deletions
diff --git a/tools/perf/util/bpf_kwork_top.c b/tools/perf/util/bpf_kwork_top.c
new file mode 100644
index 000000000000..035e02272790
--- /dev/null
+++ b/tools/perf/util/bpf_kwork_top.c
@@ -0,0 +1,308 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * bpf_kwork_top.c
+ *
+ * Copyright (c) 2022  Huawei Inc,  Yang Jihong <yangjihong1@huawei.com>
+ */
+
+#include <time.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <linux/time64.h>
+
+#include "util/debug.h"
+#include "util/evsel.h"
+#include "util/kwork.h"
+
+#include <bpf/bpf.h>
+#include <perf/cpumap.h>
+
+#include "util/bpf_skel/kwork_top.skel.h"
+
+/*
+ * This should be in sync with "util/kwork_top.bpf.c"
+ */
+#define MAX_COMMAND_LEN 16
+
+struct time_data {
+	__u64 timestamp;
+};
+
+struct work_data {
+	__u64 runtime;
+};
+
+struct task_data {
+	__u32 tgid;
+	__u32 is_kthread;
+	char comm[MAX_COMMAND_LEN];
+};
+
+struct work_key {
+	__u32 type;
+	__u32 pid;
+	__u64 task_p;
+};
+
+struct task_key {
+	__u32 pid;
+	__u32 cpu;
+};
+
+struct kwork_class_bpf {
+	struct kwork_class *class;
+	void (*load_prepare)(void);
+};
+
+static struct kwork_top_bpf *skel;
+
+void perf_kwork__top_start(void)
+{
+	struct timespec ts;
+
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	skel->bss->from_timestamp = (u64)ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec;
+	skel->bss->enabled = 1;
+	pr_debug("perf kwork top start at: %lld\n", skel->bss->from_timestamp);
+}
+
+void perf_kwork__top_finish(void)
+{
+	struct timespec ts;
+
+	skel->bss->enabled = 0;
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	skel->bss->to_timestamp = (u64)ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec;
+	pr_debug("perf kwork top finish at: %lld\n", skel->bss->to_timestamp);
+}
+
+static void irq_load_prepare(void)
+{
+	bpf_program__set_autoload(skel->progs.on_irq_handler_entry, true);
+	bpf_program__set_autoload(skel->progs.on_irq_handler_exit, true);
+}
+
+static struct kwork_class_bpf kwork_irq_bpf = {
+	.load_prepare = irq_load_prepare,
+};
+
+static void softirq_load_prepare(void)
+{
+	bpf_program__set_autoload(skel->progs.on_softirq_entry, true);
+	bpf_program__set_autoload(skel->progs.on_softirq_exit, true);
+}
+
+static struct kwork_class_bpf kwork_softirq_bpf = {
+	.load_prepare = softirq_load_prepare,
+};
+
+static void sched_load_prepare(void)
+{
+	bpf_program__set_autoload(skel->progs.on_switch, true);
+}
+
+static struct kwork_class_bpf kwork_sched_bpf = {
+	.load_prepare = sched_load_prepare,
+};
+
+static struct kwork_class_bpf *
+kwork_class_bpf_supported_list[KWORK_CLASS_MAX] = {
+	[KWORK_CLASS_IRQ]	= &kwork_irq_bpf,
+	[KWORK_CLASS_SOFTIRQ]	= &kwork_softirq_bpf,
+	[KWORK_CLASS_SCHED]	= &kwork_sched_bpf,
+};
+
+static bool valid_kwork_class_type(enum kwork_class_type type)
+{
+	return type >= 0 && type < KWORK_CLASS_MAX;
+}
+
+static int setup_filters(struct perf_kwork *kwork)
+{
+	u8 val = 1;
+	int i, nr_cpus, fd;
+	struct perf_cpu_map *map;
+
+	if (kwork->cpu_list) {
+		fd = bpf_map__fd(skel->maps.kwork_top_cpu_filter);
+		if (fd < 0) {
+			pr_debug("Invalid cpu filter fd\n");
+			return -1;
+		}
+
+		map = perf_cpu_map__new(kwork->cpu_list);
+		if (!map) {
+			pr_debug("Invalid cpu_list\n");
+			return -1;
+		}
+
+		nr_cpus = libbpf_num_possible_cpus();
+		for (i = 0; i < perf_cpu_map__nr(map); i++) {
+			struct perf_cpu cpu = perf_cpu_map__cpu(map, i);
+
+			if (cpu.cpu >= nr_cpus) {
+				perf_cpu_map__put(map);
+				pr_err("Requested cpu %d too large\n", cpu.cpu);
+				return -1;
+			}
+			bpf_map_update_elem(fd, &cpu.cpu, &val, BPF_ANY);
+		}
+		perf_cpu_map__put(map);
+
+		skel->bss->has_cpu_filter = 1;
+	}
+
+	return 0;
+}
+
+int perf_kwork__top_prepare_bpf(struct perf_kwork *kwork __maybe_unused)
+{
+	struct bpf_program *prog;
+	struct kwork_class *class;
+	struct kwork_class_bpf *class_bpf;
+	enum kwork_class_type type;
+
+	skel = kwork_top_bpf__open();
+	if (!skel) {
+		pr_debug("Failed to open kwork top skeleton\n");
+		return -1;
+	}
+
+	/*
+	 * set all progs to non-autoload,
+	 * then set corresponding progs according to config
+	 */
+	bpf_object__for_each_program(prog, skel->obj)
+		bpf_program__set_autoload(prog, false);
+
+	list_for_each_entry(class, &kwork->class_list, list) {
+		type = class->type;
+		if (!valid_kwork_class_type(type) ||
+		    !kwork_class_bpf_supported_list[type]) {
+			pr_err("Unsupported bpf trace class %s\n", class->name);
+			goto out;
+		}
+
+		class_bpf = kwork_class_bpf_supported_list[type];
+		class_bpf->class = class;
+
+		if (class_bpf->load_prepare)
+			class_bpf->load_prepare();
+	}
+
+	if (kwork_top_bpf__load(skel)) {
+		pr_debug("Failed to load kwork top skeleton\n");
+		goto out;
+	}
+
+	if (setup_filters(kwork))
+		goto out;
+
+	if (kwork_top_bpf__attach(skel)) {
+		pr_debug("Failed to attach kwork top skeleton\n");
+		goto out;
+	}
+
+	return 0;
+
+out:
+	kwork_top_bpf__destroy(skel);
+	return -1;
+}
+
+static void read_task_info(struct kwork_work *work)
+{
+	int fd;
+	struct task_data data;
+	struct task_key key = {
+		.pid = work->id,
+		.cpu = work->cpu,
+	};
+
+	fd = bpf_map__fd(skel->maps.kwork_top_tasks);
+	if (fd < 0) {
+		pr_debug("Invalid top tasks map fd\n");
+		return;
+	}
+
+	if (!bpf_map_lookup_elem(fd, &key, &data)) {
+		work->tgid = data.tgid;
+		work->is_kthread = data.is_kthread;
+		work->name = strdup(data.comm);
+	}
+}
+static int add_work(struct perf_kwork *kwork, struct work_key *key,
+		    struct work_data *data, int cpu)
+{
+	struct kwork_class_bpf *bpf_trace;
+	struct kwork_work *work;
+	struct kwork_work tmp = {
+		.id = key->pid,
+		.cpu = cpu,
+		.name = NULL,
+	};
+	enum kwork_class_type type = key->type;
+
+	if (!valid_kwork_class_type(type)) {
+		pr_debug("Invalid class type %d to add work\n", type);
+		return -1;
+	}
+
+	bpf_trace = kwork_class_bpf_supported_list[type];
+	tmp.class = bpf_trace->class;
+
+	work = perf_kwork_add_work(kwork, tmp.class, &tmp);
+	if (!work)
+		return -1;
+
+	work->total_runtime = data->runtime;
+	read_task_info(work);
+
+	return 0;
+}
+
+int perf_kwork__top_read_bpf(struct perf_kwork *kwork)
+{
+	int i, fd, nr_cpus;
+	struct work_data *data;
+	struct work_key key, prev;
+
+	fd = bpf_map__fd(skel->maps.kwork_top_works);
+	if (fd < 0) {
+		pr_debug("Invalid top runtime fd\n");
+		return -1;
+	}
+
+	nr_cpus = libbpf_num_possible_cpus();
+	data = calloc(nr_cpus, sizeof(struct work_data));
+	if (!data)
+		return -1;
+
+	memset(&prev, 0, sizeof(prev));
+	while (!bpf_map_get_next_key(fd, &prev, &key)) {
+		if ((bpf_map_lookup_elem(fd, &key, data)) != 0) {
+			pr_debug("Failed to lookup top elem\n");
+			return -1;
+		}
+
+		for (i = 0; i < nr_cpus; i++) {
+			if (data[i].runtime == 0)
+				continue;
+
+			if (add_work(kwork, &key, &data[i], i))
+				return -1;
+		}
+		prev = key;
+	}
+	free(data);
+
+	return 0;
+}
+
+void perf_kwork__top_cleanup_bpf(void)
+{
+	kwork_top_bpf__destroy(skel);
+}