Helper function bpf_timer_set_callback
This helper sets the callback function for a timer.
Definition
Copyright (c) 2015 The Libbpf Authors. All rights reserved.
Configure the timer to call callback_fn static function.
Returns
0 on success. -EINVAL if timer was not initialized with bpf_timer_init() earlier. -EPERM if timer is in a map that doesn't have any user references. The user space should either hold a file descriptor to a map with timers or pin such map in bpffs. When map is unpinned or file descriptor is closed all timers in the map will be cancelled and freed.
static long (* const bpf_timer_set_callback)(struct bpf_timer *timer, void *callback_fn) = (void *) 170;
The function passed to callback_fn
should have the following signature:
static int callback_fn(void *map, {map key type} *key, {map value type} *value)
Usage
Docs could be improved
This part of the docs is incomplete, contributions are very welcome
Program types
This helper call can be used in the following program types:
BPF_PROG_TYPE_CGROUP_DEVICE
BPF_PROG_TYPE_CGROUP_SKB
BPF_PROG_TYPE_CGROUP_SOCK
BPF_PROG_TYPE_CGROUP_SOCKOPT
BPF_PROG_TYPE_CGROUP_SOCK_ADDR
BPF_PROG_TYPE_CGROUP_SYSCTL
BPF_PROG_TYPE_FLOW_DISSECTOR
BPF_PROG_TYPE_LSM
BPF_PROG_TYPE_LWT_IN
BPF_PROG_TYPE_LWT_OUT
BPF_PROG_TYPE_LWT_SEG6LOCAL
BPF_PROG_TYPE_LWT_XMIT
BPF_PROG_TYPE_SCHED_ACT
BPF_PROG_TYPE_SCHED_CLS
BPF_PROG_TYPE_SK_LOOKUP
BPF_PROG_TYPE_SK_MSG
BPF_PROG_TYPE_SK_REUSEPORT
BPF_PROG_TYPE_SK_SKB
BPF_PROG_TYPE_SOCKET_FILTER
BPF_PROG_TYPE_SOCK_OPS
BPF_PROG_TYPE_SYSCALL
BPF_PROG_TYPE_TRACING
BPF_PROG_TYPE_XDP
Example
Docs could be improved
This part of the docs is incomplete, contributions are very welcome