Hello,
Conceptually, what would be the process behind updating a percpu map
from userspace? Looking up elements is fairly simple to digest. (For
example).
-------
int map_fd = bpf_create_map_name(
BPF_MAP_TYPE_PERCPU_ARRAY,
"map_name",
sizeof(__u32),
sizeof(__u32),
10,
0
);
int key = 4;
int values[nr_cpus];
bpf_map_lookup_elem(map_fd, &key, values);
-------
This gets the fifth element for each percpu array.
But how do you update the values in each percpu array from the
"values" array? If you can directly run bpf_map_update_elem() on the
file descriptor, does that mean that the updated value is automatically
replicated across all percpu arrays? What if you wanted to update a
specific percpu array?
