freebsd-dev/sys/netinet/ip_dummynet.h
Luigi Rizzo 5da48f88bd Some dummynet patches that I forgot to commit last summer.
One of them fixes a potential panic when bridging is used and
you run out of mbufs (though i have no idea if the bug has
ever hit anyone).
2001-01-16 23:49:49 +00:00

283 lines
11 KiB
C

/*
* Copyright (c) 1998-2000 Luigi Rizzo, Universita` di Pisa
* Portions Copyright (c) 2000 Akamba Corp.
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _IP_DUMMYNET_H
#define _IP_DUMMYNET_H
/*
* Definition of dummynet data structures.
* We first start with the heap which is used by the scheduler.
*
* Each list contains a set of parameters identifying the pipe, and
* a set of packets queued on the pipe itself.
*
* I could have used queue macros, but the management i have
* is pretty simple and this makes the code more portable.
*/
/*
* The key for the heap is used for two different values
1. timer ticks- max 10K/second, so 32 bits are enough
2. virtual times. These increase in steps of len/x, where len is the
packet length, and x is either the weight of the flow, or the
sum of all weights.
If we limit to max 1000 flows and a max weight of 100, then
x needs 17 bits. The packet size is 16 bits, so we can easily
overflow if we do not allow errors.
*/
typedef u_int64_t dn_key ; /* sorting key */
#define DN_KEY_LT(a,b) ((int64_t)((a)-(b)) < 0)
#define DN_KEY_LEQ(a,b) ((int64_t)((a)-(b)) <= 0)
#define DN_KEY_GT(a,b) ((int64_t)((a)-(b)) > 0)
#define DN_KEY_GEQ(a,b) ((int64_t)((a)-(b)) >= 0)
/* XXX check names of next two macros */
#define MAX64(x,y) (( (int64_t) ( (y)-(x) )) > 0 ) ? (y) : (x)
#define MY_M 16 /* number of left shift to obtain a larger precision */
/*
* XXX With this scaling, max 1000 flows, max weight 100, 1Gbit/s, the
* virtual time wraps every 15 days.
*/
#define OFFSET_OF(type, field) ((int)&( ((type *)0)->field) )
struct dn_heap_entry {
dn_key key ; /* sorting key. Topmost element is smallest one */
void *object ; /* object pointer */
} ;
struct dn_heap {
int size ;
int elements ;
int offset ; /* XXX if > 0 this is the offset of direct ptr to obj */
struct dn_heap_entry *p ; /* really an array of "size" entries */
} ;
/*
* MT_DUMMYNET is a new (fake) mbuf type that is prepended to the
* packet when it comes out of a pipe. The definition
* ought to go in /sys/sys/mbuf.h but here it is less intrusive.
*/
#define MT_DUMMYNET MT_CONTROL
/*
* struct dn_pkt identifies a packet in the dummynet queue. The
* first part is really an m_hdr for implementation purposes, and some
* fields are saved there. When passing the packet back to the ip_input/
* ip_output(), the struct is prepended to the mbuf chain with type
* MT_DUMMYNET, and contains the pointer to the matching rule.
*/
struct dn_pkt {
struct m_hdr hdr ;
#define dn_next hdr.mh_nextpkt /* next element in queue */
#define DN_NEXT(x) (struct dn_pkt *)(x)->dn_next
#define dn_m hdr.mh_next /* packet to be forwarded */
#define dn_dir hdr.mh_flags /* action when pkt extracted from a queue */
#define DN_TO_IP_OUT 1
#define DN_TO_IP_IN 2
#define DN_TO_BDG_FWD 3
dn_key output_time; /* when the pkt is due for delivery */
struct ifnet *ifp; /* interface, for ip_output */
struct sockaddr_in *dn_dst ;
struct route ro; /* route, for ip_output. MUST COPY */
int flags ; /* flags, for ip_output (IPv6 ?) */
};
/*
* Overall structure (with WFQ):
We have 3 data structures definining a pipe and associated queues:
+ dn_pipe, which contains the main configuration parameters related
to delay and bandwidth
+ dn_flow_set which contains WFQ configuration, flow
masks, plr and RED configuration
+ dn_flow_queue which is the per-flow queue.
Multiple dn_flow_set can be linked to the same pipe, and multiple
dn_flow_queue can be linked to the same dn_flow_set.
During configuration we set the dn_flow_set and dn_pipe parameters.
At runtime: packets are sent to the dn_flow_set (either WFQ ones, or
the one embedded in the dn_pipe for fixed-rate flows) which in turn
dispatches them to the appropriate dn_flow_queue (created dynamically
according to the masks).
The transmit clock for fixed rate flows (ready_event) selects the
dn_flow_queue to be used to transmit the next packet. For WF2Q,
wfq_ready_event() extract a pipe which in turn selects the right
flow using a number of heaps defined into the pipe.
*
*/
/*
* We use per flow queues. Hashing is used to select the right slot,
* then we scan the list to match the flow-id.
*/
struct dn_flow_queue {
struct dn_flow_queue *next ;
struct ipfw_flow_id id ;
struct dn_pkt *head, *tail ; /* queue of packets */
u_int len ;
u_int len_bytes ;
long numbytes ; /* credit for transmission (dynamic queues) */
u_int64_t tot_pkts ; /* statistics counters */
u_int64_t tot_bytes ;
u_int32_t drops ;
int hash_slot ; /* debugging/diagnostic */
/* RED parameters */
int avg ; /* average queue length est. (scaled) */
int count ; /* arrivals since last RED drop */
int random ; /* random value (scaled) */
u_int32_t q_time ; /* start of queue idle time */
/* WF2Q+ support */
struct dn_flow_set *fs ; /* parent flow set */
int blh_pos ; /* position in backlogged_heap */
dn_key sched_time ; /* current time when queue enters ready_heap */
dn_key S,F ; /* start-time, finishing time */
/* setting F < S means the timestamp is invalid. We only need
* to test this when the queue is empty.
*/
} ;
struct dn_flow_set {
struct dn_flow_set *next; /* next flow set in all_flow_sets list */
u_short fs_nr ; /* flow_set number */
u_short flags_fs;
#define DN_HAVE_FLOW_MASK 0x0001
#define DN_IS_PIPE 0x4000
#define DN_IS_QUEUE 0x8000
#define DN_IS_RED 0x0002
#define DN_IS_GENTLE_RED 0x0004
#define DN_QSIZE_IS_BYTES 0x0008 /* queue measured in bytes */
struct dn_pipe *pipe ; /* pointer to parent pipe */
u_short parent_nr ; /* parent pipe#, 0 if local to a pipe */
int weight ; /* WFQ queue weight */
int qsize ; /* queue size in slots or bytes */
int plr ; /* pkt loss rate (2^31-1 means 100%) */
struct ipfw_flow_id flow_mask ;
/* hash table of queues onto this flow_set */
int rq_size ; /* number of slots */
int rq_elements ; /* active elements */
struct dn_flow_queue **rq; /* array of rq_size entries */
u_int32_t last_expired ; /* do not expire too frequently */
/* XXX some RED parameters as well ? */
int backlogged ; /* #active queues for this flowset */
/* RED parameters */
#define SCALE_RED 16
#define SCALE(x) ( (x) << SCALE_RED )
#define SCALE_VAL(x) ( (x) >> SCALE_RED )
#define SCALE_MUL(x,y) ( ( (x) * (y) ) >> SCALE_RED )
int w_q ; /* queue weight (scaled) */
int max_th ; /* maximum threshold for queue (scaled) */
int min_th ; /* minimum threshold for queue (scaled) */
int max_p ; /* maximum value for p_b (scaled) */
u_int c_1 ; /* max_p/(max_th-min_th) (scaled) */
u_int c_2 ; /* max_p*min_th/(max_th-min_th) (scaled) */
u_int c_3 ; /* for GRED, (1-max_p)/max_th (scaled) */
u_int c_4 ; /* for GRED, 1 - 2*max_p (scaled) */
u_int * w_q_lookup ; /* lookup table for computing (1-w_q)^t */
u_int lookup_depth ; /* depth of lookup table */
int lookup_step ; /* granularity inside the lookup table */
int lookup_weight ; /* equal to (1-w_q)^t / (1-w_q)^(t+1) */
int avg_pkt_size ; /* medium packet size */
int max_pkt_size ; /* max packet size */
} ;
/*
* Pipe descriptor. Contains global parameters, delay-line queue.
*
* For WF2Q support it also has 3 heaps holding dn_flow_queue:
* not_eligible_heap, for queues whose start time is higher
* than the virtual time. Sorted by start time.
* scheduler_heap, for queues eligible for scheduling. Sorted by
* finish time.
* backlogged_heap, all flows in the two heaps above, sorted by
* start time. This is used to compute the virtual time.
*
*/
struct dn_pipe { /* a pipe */
struct dn_pipe *next ;
int pipe_nr ; /* number */
int bandwidth; /* really, bytes/tick. */
int delay ; /* really, ticks */
struct dn_pkt *head, *tail ; /* packets in delay line */
/* WF2Q+ */
struct dn_heap scheduler_heap ; /* top extract - key Finish time*/
struct dn_heap not_eligible_heap; /* top extract- key Start time */
struct dn_heap backlogged_heap ; /* random extract - key Start time */
struct dn_heap idle_heap ; /* random extract - key Start=Finish time */
dn_key V ; /* virtual time */
int sum; /* sum of weights of all active sessions */
int numbytes; /* bit i can transmit (more or less). */
dn_key sched_time ; /* first time pipe is scheduled in ready_heap */
/* the tx clock can come from an interface. In this case, the
* name is below, and the pointer is filled when the rule is
* configured. We identify this by setting the if_name to a
* non-empty string.
*/
char if_name[16];
struct ifnet *ifp ;
int ready ; /* set if ifp != NULL and we got a signal from it */
struct dn_flow_set fs ; /* used with fixed-rate flows */
};
#ifdef _KERNEL
MALLOC_DECLARE(M_IPFW);
typedef int ip_dn_ctl_t __P((struct sockopt *)) ;
extern ip_dn_ctl_t *ip_dn_ctl_ptr;
void dn_rule_delete(void *r); /* used in ip_fw.c */
int dummynet_io(int pipe, int dir,
struct mbuf *m, struct ifnet *ifp, struct route *ro,
struct sockaddr_in * dst,
struct ip_fw_chain *rule, int flags);
#endif
#endif /* _IP_DUMMYNET_H */