bpftool: fix percpu maps updating (b0ca5ecb) · Commits · 戴 / test

When updating a percpu map, bpftool currently copies the provided value only into the first per CPU copy of the specified value, all others instances are left zeroed. This change explicitly copies the user-provided bytes to all the per CPU instances, keeping the sub-command syntax unchanged. v2 -> v3: - drop unused argument, as per Quentin's suggestion v1 -> v2: - rename the helper as per Quentin's suggestion Fixes: ("tools: bpf: add bpftool") Signed-off-by:

Paolo Abeni <pabeni@redhat.com> Reviewed-by:

Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by:

Daniel Borkmann <daniel@iogearbox.net>

tools/bpf/bpftool/map.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -347,6 +347,20 @@ static char parse_bytes(char argv, const char name, unsigned char val,
		return argv + i;
		}

		/* on per cpu maps we must copy the provided value on all value instances */
		static void fill_per_cpu_value(struct bpf_map_info info, void value)
		{
		unsigned int i, n, step;

		if (!map_is_per_cpu(info->type))
		return;

		n = get_possible_cpus();
		step = round_up(info->value_size, 8);
		for (i = 1; i < n; i++)
		memcpy(value + i * step, value, info->value_size);
		}

		static int parse_elem(char *argv, struct bpf_map_info info,
		void key, void value, __u32 key_size, __u32 value_size,
		__u32 flags, __u32 *value_fd)
		@@ -426,6 +440,8 @@ static int parse_elem(char *argv, struct bpf_map_info info,
		argv = parse_bytes(argv, "value", value, value_size);
		if (!argv)
		return -1;

		fill_per_cpu_value(info, value);
		}

		return parse_elem(argv, info, key, NULL, key_size, value_size,

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