forked from mirrors/linux
		
	 23ad04669f
			
		
	
	
		23ad04669f
		
	
	
	
	
		
			
			GCC 10 is very strict about symbol clash, and lwt_len_hist_user contains a symbol which clashes with libbpf: /usr/bin/ld: samples/bpf/lwt_len_hist_user.o:(.bss+0x0): multiple definition of `bpf_log_buf'; samples/bpf/bpf_load.o:(.bss+0x8c0): first defined here collect2: error: ld returned 1 exit status bpf_log_buf here seems to be a leftover, so removing it. Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200511113234.80722-1-mcroce@redhat.com
		
			
				
	
	
		
			77 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| #include <linux/unistd.h>
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| #include <linux/bpf.h>
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| 
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| #include <stdlib.h>
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| #include <stdio.h>
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| #include <unistd.h>
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| #include <string.h>
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| #include <errno.h>
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| #include <arpa/inet.h>
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| 
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| #include <bpf/bpf.h>
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| #include "bpf_util.h"
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| 
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| #define MAX_INDEX 64
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| #define MAX_STARS 38
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| 
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| static void stars(char *str, long val, long max, int width)
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| {
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| 	int i;
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| 
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| 	for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++)
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| 		str[i] = '*';
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| 	if (val > max)
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| 		str[i - 1] = '+';
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| 	str[i] = '\0';
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| }
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| 
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| int main(int argc, char **argv)
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| {
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| 	unsigned int nr_cpus = bpf_num_possible_cpus();
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| 	const char *map_filename = "/sys/fs/bpf/tc/globals/lwt_len_hist_map";
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| 	uint64_t values[nr_cpus], sum, max_value = 0, data[MAX_INDEX] = {};
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| 	uint64_t key = 0, next_key, max_key = 0;
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| 	char starstr[MAX_STARS];
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| 	int i, map_fd;
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| 
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| 	map_fd = bpf_obj_get(map_filename);
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| 	if (map_fd < 0) {
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| 		fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n",
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| 			map_filename, strerror(errno), errno);
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| 		return -1;
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| 	}
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| 
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| 	while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) {
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| 		if (next_key >= MAX_INDEX) {
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| 			fprintf(stderr, "Key %lu out of bounds\n", next_key);
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| 			continue;
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| 		}
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| 
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| 		bpf_map_lookup_elem(map_fd, &next_key, values);
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| 
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| 		sum = 0;
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| 		for (i = 0; i < nr_cpus; i++)
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| 			sum += values[i];
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| 
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| 		data[next_key] = sum;
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| 		if (sum && next_key > max_key)
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| 			max_key = next_key;
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| 
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| 		if (sum > max_value)
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| 			max_value = sum;
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| 
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| 		key = next_key;
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| 	}
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| 
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| 	for (i = 1; i <= max_key + 1; i++) {
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| 		stars(starstr, data[i - 1], max_value, MAX_STARS);
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| 		printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
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| 		       (1l << i) >> 1, (1l << i) - 1, data[i - 1],
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| 		       MAX_STARS, starstr);
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| 	}
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| 
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| 	close(map_fd);
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| 
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| 	return 0;
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| }
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