ifq_enqueue,
ifq_dequeue,
ifq_purge,
ifq_len,
ifq_empty,
ifq_set_oactive,
ifq_clr_oactive,
ifq_is_oactive,
ifq_restart,
ifq_barrier —
interface send queue API
#include
<net/if_var.h>
int
ifq_enqueue(
struct
ifqueue *ifq,
struct mbuf *m);
struft mbuf *
ifq_dequeue(
struct
ifqueue *ifq);
unsigned int
ifq_purge(
struct
ifqueue *ifq);
unsigned int
ifq_len(
struct
ifqueue *ifq);
unsigned int
ifq_empty(
struct
ifqueue *ifq);
void
ifq_set_oactive(
struct
ifqueue *ifq);
void
ifq_clr_oactive(
struct
ifqueue *ifq);
unsigned int
ifq_is_oactive(
struct
ifqueue *ifq);
void
ifq_restart(
struct
ifqueue *ifq);
void
ifq_barrier(
struct
ifqueue *ifq);
The ifqueue API provides implementions of data structures and operations for the
network stack to queue mbufs for a network driver to dequeue from its start
routine for transmission.
-
-
- ifq_enqueue(struct
ifqueue *ifq, struct mbuf *m)
- Enqueue mbuf m on the
ifq interface send queue. If the queue
rejects the packet it will be freed with
m_freem(9) and counted as a
drop.
-
-
- ifq_dequeue(struct
ifqueue *ifq)
- Dequeue the next mbuf to be transmitted from the
ifq interface send queue.
-
-
- ifq_purge(struct
ifqueue *ifq)
- Free all the mbufs on the interface send queue
ifq. Freed mbufs will be accounted as
drops.
-
-
- ifq_len(struct
ifqueue *ifq)
- Return the number of mbufs on the interface send queue
ifq. Note that while
ifq_len() may report that mbufs are on the
queue, the current queue discipline may not make them available for
dequeueing with ifq_dequeue() or
ifq_deq_begin().
-
-
- ifq_empty(struct
ifqueue *ifq)
- Return if the interface send queue
ifq is empty.
-
-
- ifq_set_oactive(struct
ifqueue *ifq)
- ifq_set_oactive() is called by
the relevant driver to mark the hardware associated with the interface
send queue ifq as unable to transmit more
packets.
-
-
- ifq_clr_oactive(struct
ifqueue *ifq)
- ifq_clr_oactive() is called by
the relevant driver to clear the "active" mark on the hardware
associated with the interface send queue
ifq, meaning it is now able to transmit
packets.
-
-
- ifq_is_oactive(struct
ifqueue *ifq)
- Return if the hardware associated with the interface send
queue ifq is unable to transmit more
packets.
-
-
- ifq_restart(struct
ifqueue *ifq)
- Dispatch a call to
ifq_clr_oactive() and the interface's start
routine. This call is serialised with other calls to the start routine via
if_start() and therefore provides race free
modification of the "active" mark.
-
-
- ifq_barrier(struct
ifqueue *ifq)
- ifq_barrier() guarantees that
any work currently running in the interface queue serialiser (e.g. work
dispatched by ifq_restart() or the
interface's start routine) has finished before
ifq_barrier() returns.
ifq_enqueue(),
ifq_dequeue(),
ifq_purge(),
ifq_len(),
ifq_empty(),
ifq_set_oactive(),
ifq_clr_oactive(),
ifq_is_oactive(), and
ifq_restart() can be called during autoconf, from
process context, or from interrupt context.
ifq_barrier() can be called from process context.
ifq_enqueue() returns 0 if the mbuf was
successfully queued, or non-zero if mbuf was freed.
ifq_dequeue() returns the next mbuf to be
transmitted by the interface. If no packet is available for transmission,
NULL is returned.
ifq_purge() returns the number of mbufs that were
removed from the queue and freed.
ifq_len() returns the number of mbufs on the queue.
ifq_empty() returns a non-zero value if the queue
is empty, otherwise 0.
ifq_is_oactive() returns a non-zero value if the
hardware associated with the interface send queue is unable to transmit more
packets, otherwise 0.
ifq_deq_begin(9),
m_freem(9)
![[OpenBSD]](/openbsd.gif){kind=small}