[linux-2.6-block.git] / samples / bpf / trace_event_kern.c

/* Copyright (c) 2016 Facebook
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 */
#include <linux/ptrace.h>
#include <linux/version.h>
#include <uapi/linux/bpf.h>
#include <uapi/linux/bpf_perf_event.h>
#include <uapi/linux/perf_event.h>
#include "bpf_helpers.h"

struct key_t {
	char comm[TASK_COMM_LEN];
	u32 kernstack;
	u32 userstack;
};

struct bpf_map_def SEC("maps") counts = {
	.type = BPF_MAP_TYPE_HASH,
	.key_size = sizeof(struct key_t),
	.value_size = sizeof(u64),
	.max_entries = 10000,
};

struct bpf_map_def SEC("maps") stackmap = {
	.type = BPF_MAP_TYPE_STACK_TRACE,
	.key_size = sizeof(u32),
	.value_size = PERF_MAX_STACK_DEPTH * sizeof(u64),
	.max_entries = 10000,
};

#define KERN_STACKID_FLAGS (0 | BPF_F_FAST_STACK_CMP)
#define USER_STACKID_FLAGS (0 | BPF_F_FAST_STACK_CMP | BPF_F_USER_STACK)

SEC("perf_event")
int bpf_prog1(struct bpf_perf_event_data *ctx)
{
	char time_fmt1[] = "Time Enabled: %llu, Time Running: %llu";
	char time_fmt2[] = "Get Time Failed, ErrCode: %d";
	char addr_fmt[] = "Address recorded on event: %llx";
	char fmt[] = "CPU-%d period %lld ip %llx";
	u32 cpu = bpf_get_smp_processor_id();
	struct bpf_perf_event_value value_buf;
	struct key_t key;
	u64 *val, one = 1;
	int ret;

	if (ctx->sample_period < 10000)
		/* ignore warmup */
		return 0;
	bpf_get_current_comm(&key.comm, sizeof(key.comm));
	key.kernstack = bpf_get_stackid(ctx, &stackmap, KERN_STACKID_FLAGS);
	key.userstack = bpf_get_stackid(ctx, &stackmap, USER_STACKID_FLAGS);
	if ((int)key.kernstack < 0 && (int)key.userstack < 0) {
		bpf_trace_printk(fmt, sizeof(fmt), cpu, ctx->sample_period,
				 PT_REGS_IP(&ctx->regs));
		return 0;
	}

	ret = bpf_perf_prog_read_value(ctx, (void *)&value_buf, sizeof(struct bpf_perf_event_value));
	if (!ret)
	  bpf_trace_printk(time_fmt1, sizeof(time_fmt1), value_buf.enabled, value_buf.running);
	else
	  bpf_trace_printk(time_fmt2, sizeof(time_fmt2), ret);

	if (ctx->addr != 0)
	  bpf_trace_printk(addr_fmt, sizeof(addr_fmt), ctx->addr);

	val = bpf_map_lookup_elem(&counts, &key);
	if (val)
		(*val)++;
	else
		bpf_map_update_elem(&counts, &key, &one, BPF_NOEXIST);
	return 0;
}

char _license[] SEC("license") = "GPL";
Commit	Line	Data
1c47910e AS	1	/* Copyright (c) 2016 Facebook
	2	*
	3	* This program is free software; you can redistribute it and/or
	4	* modify it under the terms of version 2 of the GNU General Public
	5	* License as published by the Free Software Foundation.
	6	*/
	7	#include <linux/ptrace.h>
	8	#include <linux/version.h>
	9	#include <uapi/linux/bpf.h>
	10	#include <uapi/linux/bpf_perf_event.h>
	11	#include <uapi/linux/perf_event.h>
	12	#include "bpf_helpers.h"
	13
	14	struct key_t {
	15	char comm[TASK_COMM_LEN];
	16	u32 kernstack;
	17	u32 userstack;
	18	};
	19
	20	struct bpf_map_def SEC("maps") counts = {
	21	.type = BPF_MAP_TYPE_HASH,
	22	.key_size = sizeof(struct key_t),
	23	.value_size = sizeof(u64),
	24	.max_entries = 10000,
	25	};
	26
	27	struct bpf_map_def SEC("maps") stackmap = {
	28	.type = BPF_MAP_TYPE_STACK_TRACE,
	29	.key_size = sizeof(u32),
	30	.value_size = PERF_MAX_STACK_DEPTH * sizeof(u64),
	31	.max_entries = 10000,
	32	};
	33
	34	#define KERN_STACKID_FLAGS (0 \| BPF_F_FAST_STACK_CMP)
	35	#define USER_STACKID_FLAGS (0 \| BPF_F_FAST_STACK_CMP \| BPF_F_USER_STACK)
	36
	37	SEC("perf_event")
	38	int bpf_prog1(struct bpf_perf_event_data *ctx)
	39	{
81b9cf80 YS	40	char time_fmt1[] = "Time Enabled: %llu, Time Running: %llu";
81b9cf80 YS	41	char time_fmt2[] = "Get Time Failed, ErrCode: %d";
12fe1225	42	char addr_fmt[] = "Address recorded on event: %llx";
1c47910e AS	43	char fmt[] = "CPU-%d period %lld ip %llx";
1c47910e AS	44	u32 cpu = bpf_get_smp_processor_id();
81b9cf80	45	struct bpf_perf_event_value value_buf;
1c47910e AS	46	struct key_t key;
1c47910e AS	47	u64 *val, one = 1;
81b9cf80	48	int ret;
1c47910e AS	49
	50	if (ctx->sample_period < 10000)
	51	/* ignore warmup */
	52	return 0;
	53	bpf_get_current_comm(&key.comm, sizeof(key.comm));
	54	key.kernstack = bpf_get_stackid(ctx, &stackmap, KERN_STACKID_FLAGS);
	55	key.userstack = bpf_get_stackid(ctx, &stackmap, USER_STACKID_FLAGS);
	56	if ((int)key.kernstack < 0 && (int)key.userstack < 0) {
	57	bpf_trace_printk(fmt, sizeof(fmt), cpu, ctx->sample_period,
2dbb4c05	58	PT_REGS_IP(&ctx->regs));
1c47910e AS	59	return 0;
	60	}
	61
81b9cf80 YS	62	ret = bpf_perf_prog_read_value(ctx, (void *)&value_buf, sizeof(struct bpf_perf_event_value));
	63	if (!ret)
	64	bpf_trace_printk(time_fmt1, sizeof(time_fmt1), value_buf.enabled, value_buf.running);
	65	else
	66	bpf_trace_printk(time_fmt2, sizeof(time_fmt2), ret);
	67
12fe1225 TQ	68	if (ctx->addr != 0)
	69	bpf_trace_printk(addr_fmt, sizeof(addr_fmt), ctx->addr);
	70
1c47910e AS	71	val = bpf_map_lookup_elem(&counts, &key);
	72	if (val)
	73	(*val)++;
	74	else
	75	bpf_map_update_elem(&counts, &key, &one, BPF_NOEXIST);
	76	return 0;
	77	}
	78
	79	char _license[] SEC("license") = "GPL";