Commit ce4dade7 authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Daniel Borkmann
Browse files

samples/bpf: xdp_redirect_cpu: Load a eBPF program on cpumap 



Extend xdp_redirect_cpu_{usr,kern}.c adding the possibility to load
a XDP program on cpumap entries. The following options have been added:
- mprog-name: cpumap entry program name
- mprog-filename: cpumap entry program filename
- redirect-device: output interface if the cpumap program performs a
  XDP_REDIRECT to an egress interface
- redirect-map: bpf map used to perform XDP_REDIRECT to an egress
  interface
- mprog-disable: disable loading XDP program on cpumap entries

Add xdp_pass, xdp_drop, xdp_redirect stats accounting

Co-developed-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/aa5a9a281b9dac425620fdabe82670ffb6bbdb92.1594734381.git.lorenzo@kernel.org
parent 4be556cf

samples/bpf/xdp_redirect_cpu_kern.c

+17 −8
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ 
struct {

	__uint(type, BPF_MAP_TYPE_CPUMAP);

	__uint(key_size, sizeof(u32));

	__uint(value_size, sizeof(u32));

	__uint(value_size, sizeof(struct bpf_cpumap_val));

	__uint(max_entries, MAX_CPUS);

} cpu_map SEC(".maps");
@@ -30,6 +30,9 @@ struct datarec { 
	__u64 processed;

	__u64 dropped;

	__u64 issue;

	__u64 xdp_pass;

	__u64 xdp_drop;

	__u64 xdp_redirect;

};



/* Count RX packets, as XDP bpf_prog doesn't get direct TX-success
@@ -692,13 +695,16 @@ int trace_xdp_cpumap_enqueue(struct cpumap_enqueue_ctx *ctx) 
 * Code in:         kernel/include/trace/events/xdp.h

 */

struct cpumap_kthread_ctx {

	u64 __pad;		// First 8 bytes are not accessible by bpf code

	u64 __pad;			// First 8 bytes are not accessible

	int map_id;			//	offset:8;  size:4; signed:1;

	u32 act;			//	offset:12; size:4; signed:0;

	int cpu;			//	offset:16; size:4; signed:1;

	unsigned int drops;		//	offset:20; size:4; signed:0;

	unsigned int processed;		//	offset:24; size:4; signed:0;

	int sched;			//	offset:28; size:4; signed:1;

	unsigned int xdp_pass;		//	offset:32; size:4; signed:0;

	unsigned int xdp_drop;		//	offset:36; size:4; signed:0;

	unsigned int xdp_redirect;	//	offset:40; size:4; signed:0;

};



SEC("tracepoint/xdp/xdp_cpumap_kthread")
@@ -712,6 +718,9 @@ int trace_xdp_cpumap_kthread(struct cpumap_kthread_ctx *ctx) 
		return 0;

	rec->processed += ctx->processed;

	rec->dropped   += ctx->drops;

	rec->xdp_pass  += ctx->xdp_pass;

	rec->xdp_drop  += ctx->xdp_drop;

	rec->xdp_redirect  += ctx->xdp_redirect;



	/* Count times kthread yielded CPU via schedule call */

	if (ctx->sched)

samples/bpf/xdp_redirect_cpu_user.c

+161 −14
Original line number Diff line number Diff line
@@ -70,6 +70,11 @@ static const struct option long_options[] = { 
	{"stress-mode", no_argument,		NULL, 'x' },

	{"no-separators", no_argument,		NULL, 'z' },

	{"force",	no_argument,		NULL, 'F' },

	{"mprog-disable", no_argument,		NULL, 'n' },

	{"mprog-name",	required_argument,	NULL, 'e' },

	{"mprog-filename", required_argument,	NULL, 'f' },

	{"redirect-device", required_argument,	NULL, 'r' },

	{"redirect-map", required_argument,	NULL, 'm' },

	{0, 0, NULL,  0 }

};
@@ -156,6 +161,9 @@ struct datarec { 
	__u64 processed;

	__u64 dropped;

	__u64 issue;

	__u64 xdp_pass;

	__u64 xdp_drop;

	__u64 xdp_redirect;

};

struct record {

	__u64 timestamp;
@@ -175,6 +183,9 @@ static bool map_collect_percpu(int fd, __u32 key, struct record *rec) 
	/* For percpu maps, userspace gets a value per possible CPU */

	unsigned int nr_cpus = bpf_num_possible_cpus();

	struct datarec values[nr_cpus];

	__u64 sum_xdp_redirect = 0;

	__u64 sum_xdp_pass = 0;

	__u64 sum_xdp_drop = 0;

	__u64 sum_processed = 0;

	__u64 sum_dropped = 0;

	__u64 sum_issue = 0;
@@ -196,10 +207,19 @@ static bool map_collect_percpu(int fd, __u32 key, struct record *rec) 
		sum_dropped        += values[i].dropped;

		rec->cpu[i].issue = values[i].issue;

		sum_issue        += values[i].issue;

		rec->cpu[i].xdp_pass = values[i].xdp_pass;

		sum_xdp_pass += values[i].xdp_pass;

		rec->cpu[i].xdp_drop = values[i].xdp_drop;

		sum_xdp_drop += values[i].xdp_drop;

		rec->cpu[i].xdp_redirect = values[i].xdp_redirect;

		sum_xdp_redirect += values[i].xdp_redirect;

	}

	rec->total.processed = sum_processed;

	rec->total.dropped   = sum_dropped;

	rec->total.issue     = sum_issue;

	rec->total.xdp_pass  = sum_xdp_pass;

	rec->total.xdp_drop  = sum_xdp_drop;

	rec->total.xdp_redirect = sum_xdp_redirect;

	return true;

}
@@ -300,17 +320,33 @@ static __u64 calc_errs_pps(struct datarec *r, 
	return pps;

}



static void calc_xdp_pps(struct datarec *r, struct datarec *p,

			 double *xdp_pass, double *xdp_drop,

			 double *xdp_redirect, double period_)

{

	*xdp_pass = 0, *xdp_drop = 0, *xdp_redirect = 0;

	if (period_ > 0) {

		*xdp_redirect = (r->xdp_redirect - p->xdp_redirect) / period_;

		*xdp_pass = (r->xdp_pass - p->xdp_pass) / period_;

		*xdp_drop = (r->xdp_drop - p->xdp_drop) / period_;

	}

}



static void stats_print(struct stats_record *stats_rec,

			struct stats_record *stats_prev,

			char *prog_name)

			char *prog_name, char *mprog_name, int mprog_fd)

{

	unsigned int nr_cpus = bpf_num_possible_cpus();

	double pps = 0, drop = 0, err = 0;

	bool mprog_enabled = false;

	struct record *rec, *prev;

	int to_cpu;

	double t;

	int i;



	if (mprog_fd > 0)

		mprog_enabled = true;



	/* Header */

	printf("Running XDP/eBPF prog_name:%s\n", prog_name);

	printf("%-15s %-7s %-14s %-11s %-9s\n",
@@ -455,6 +491,34 @@ static void stats_print(struct stats_record *stats_rec, 
		printf(fm2_err, "xdp_exception", "total", pps, drop);

	}



	/* CPUMAP attached XDP program that runs on remote/destination CPU */

	if (mprog_enabled) {

		char *fmt_k = "%-15s %-7d %'-14.0f %'-11.0f %'-10.0f\n";

		char *fm2_k = "%-15s %-7s %'-14.0f %'-11.0f %'-10.0f\n";

		double xdp_pass, xdp_drop, xdp_redirect;



		printf("\n2nd remote XDP/eBPF prog_name: %s\n", mprog_name);

		printf("%-15s %-7s %-14s %-11s %-9s\n",

		       "XDP-cpumap", "CPU:to", "xdp-pass", "xdp-drop", "xdp-redir");



		rec  = &stats_rec->kthread;

		prev = &stats_prev->kthread;

		t = calc_period(rec, prev);

		for (i = 0; i < nr_cpus; i++) {

			struct datarec *r = &rec->cpu[i];

			struct datarec *p = &prev->cpu[i];



			calc_xdp_pps(r, p, &xdp_pass, &xdp_drop,

				     &xdp_redirect, t);

			if (xdp_pass > 0 || xdp_drop > 0 || xdp_redirect > 0)

				printf(fmt_k, "xdp-in-kthread", i, xdp_pass, xdp_drop,

				       xdp_redirect);

		}

		calc_xdp_pps(&rec->total, &prev->total, &xdp_pass, &xdp_drop,

			     &xdp_redirect, t);

		printf(fm2_k, "xdp-in-kthread", "total", xdp_pass, xdp_drop, xdp_redirect);

	}



	printf("\n");

	fflush(stdout);

}
@@ -491,7 +555,7 @@ static inline void swap(struct stats_record **a, struct stats_record **b) 
	*b = tmp;

}



static int create_cpu_entry(__u32 cpu, __u32 queue_size,

static int create_cpu_entry(__u32 cpu, struct bpf_cpumap_val *value,

			    __u32 avail_idx, bool new)

{

	__u32 curr_cpus_count = 0;
@@ -501,7 +565,7 @@ static int create_cpu_entry(__u32 cpu, __u32 queue_size, 
	/* Add a CPU entry to cpumap, as this allocate a cpu entry in

	 * the kernel for the cpu.

	 */

	ret = bpf_map_update_elem(cpu_map_fd, &cpu, &queue_size, 0);

	ret = bpf_map_update_elem(cpu_map_fd, &cpu, value, 0);

	if (ret) {

		fprintf(stderr, "Create CPU entry failed (err:%d)\n", ret);

		exit(EXIT_FAIL_BPF);
@@ -532,9 +596,9 @@ static int create_cpu_entry(__u32 cpu, __u32 queue_size, 
		}

	}

	/* map_fd[7] = cpus_iterator */

	printf("%s CPU:%u as idx:%u queue_size:%d (total cpus_count:%u)\n",

	printf("%s CPU:%u as idx:%u qsize:%d prog_fd: %d (cpus_count:%u)\n",

	       new ? "Add-new":"Replace", cpu, avail_idx,

	       queue_size, curr_cpus_count);

	       value->qsize, value->bpf_prog.fd, curr_cpus_count);



	return 0;

}
@@ -558,21 +622,26 @@ static void mark_cpus_unavailable(void) 
}



/* Stress cpumap management code by concurrently changing underlying cpumap */

static void stress_cpumap(void)

static void stress_cpumap(struct bpf_cpumap_val *value)

{

	/* Changing qsize will cause kernel to free and alloc a new

	 * bpf_cpu_map_entry, with an associated/complicated tear-down

	 * procedure.

	 */

	create_cpu_entry(1,  1024, 0, false);

	create_cpu_entry(1,     8, 0, false);

	create_cpu_entry(1, 16000, 0, false);

	value->qsize = 1024;

	create_cpu_entry(1, value, 0, false);

	value->qsize = 8;

	create_cpu_entry(1, value, 0, false);

	value->qsize = 16000;

	create_cpu_entry(1, value, 0, false);

}



static void stats_poll(int interval, bool use_separators, char *prog_name,

		       char *mprog_name, struct bpf_cpumap_val *value,

		       bool stress_mode)

{

	struct stats_record *record, *prev;

	int mprog_fd;



	record = alloc_stats_record();

	prev   = alloc_stats_record();
@@ -584,11 +653,12 @@ static void stats_poll(int interval, bool use_separators, char *prog_name, 


	while (1) {

		swap(&prev, &record);

		mprog_fd = value->bpf_prog.fd;

		stats_collect(record);

		stats_print(record, prev, prog_name);

		stats_print(record, prev, prog_name, mprog_name, mprog_fd);

		sleep(interval);

		if (stress_mode)

			stress_cpumap();

			stress_cpumap(value);

	}



	free_stats_record(record);
@@ -661,15 +731,66 @@ static int init_map_fds(struct bpf_object *obj) 
	return 0;

}



static int load_cpumap_prog(char *file_name, char *prog_name,

			    char *redir_interface, char *redir_map)

{

	struct bpf_prog_load_attr prog_load_attr = {

		.prog_type		= BPF_PROG_TYPE_XDP,

		.expected_attach_type	= BPF_XDP_CPUMAP,

		.file = file_name,

	};

	struct bpf_program *prog;

	struct bpf_object *obj;

	int fd;



	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &fd))

		return -1;



	if (fd < 0) {

		fprintf(stderr, "ERR: bpf_prog_load_xattr: %s\n",

			strerror(errno));

		return fd;

	}



	if (redir_interface && redir_map) {

		int err, map_fd, ifindex_out, key = 0;



		map_fd = bpf_object__find_map_fd_by_name(obj, redir_map);

		if (map_fd < 0)

			return map_fd;



		ifindex_out = if_nametoindex(redir_interface);

		if (!ifindex_out)

			return -1;



		err = bpf_map_update_elem(map_fd, &key, &ifindex_out, 0);

		if (err < 0)

			return err;

	}



	prog = bpf_object__find_program_by_title(obj, prog_name);

	if (!prog) {

		fprintf(stderr, "bpf_object__find_program_by_title failed\n");

		return EXIT_FAIL;

	}



	return bpf_program__fd(prog);

}



int main(int argc, char **argv)

{

	struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};

	char *prog_name = "xdp_cpu_map5_lb_hash_ip_pairs";

	char *mprog_filename = "xdp_redirect_kern.o";

	char *redir_interface = NULL, *redir_map = NULL;

	char *mprog_name = "xdp_redirect_dummy";

	bool mprog_disable = false;

	struct bpf_prog_load_attr prog_load_attr = {

		.prog_type	= BPF_PROG_TYPE_UNSPEC,

	};

	struct bpf_prog_info info = {};

	__u32 info_len = sizeof(info);

	struct bpf_cpumap_val value;

	bool use_separators = true;

	bool stress_mode = false;

	struct bpf_program *prog;
@@ -725,7 +846,7 @@ int main(int argc, char **argv) 
	memset(cpu, 0, n_cpus * sizeof(int));



	/* Parse commands line args */

	while ((opt = getopt_long(argc, argv, "hSd:s:p:q:c:xzF",

	while ((opt = getopt_long(argc, argv, "hSd:s:p:q:c:xzFf:e:r:m:",

				  long_options, &longindex)) != -1) {

		switch (opt) {

		case 'd':
@@ -759,6 +880,21 @@ int main(int argc, char **argv) 
			/* Selecting eBPF prog to load */

			prog_name = optarg;

			break;

		case 'n':

			mprog_disable = true;

			break;

		case 'f':

			mprog_filename = optarg;

			break;

		case 'e':

			mprog_name = optarg;

			break;

		case 'r':

			redir_interface = optarg;

			break;

		case 'm':

			redir_map = optarg;

			break;

		case 'c':

			/* Add multiple CPUs */

			add_cpu = strtoul(optarg, NULL, 0);
@@ -804,8 +940,18 @@ int main(int argc, char **argv) 
		goto out;

	}



	value.bpf_prog.fd = 0;

	if (!mprog_disable)

		value.bpf_prog.fd = load_cpumap_prog(mprog_filename, mprog_name,

						     redir_interface, redir_map);

	if (value.bpf_prog.fd < 0) {

		err = value.bpf_prog.fd;

		goto out;

	}

	value.qsize = qsize;



	for (i = 0; i < added_cpus; i++)

		create_cpu_entry(cpu[i], qsize, i, true);

		create_cpu_entry(cpu[i], &value, i, true);



	/* Remove XDP program when program is interrupted or killed */

	signal(SIGINT, int_exit);
@@ -838,7 +984,8 @@ int main(int argc, char **argv) 
	}

	prog_id = info.id;



	stats_poll(interval, use_separators, prog_name, stress_mode);

	stats_poll(interval, use_separators, prog_name, mprog_name,

		   &value, stress_mode);

out:

	free(cpu);

	return err;

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