[NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.
Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:
->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
a specific protocol
The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.
I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.
Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)
Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index e71f8ba..d438ba5 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -31,6 +31,7 @@
#include <linux/cache.h>
#include <linux/percpu.h>
#include <net/checksum.h>
+#include <net/request_sock.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ip.h>
@@ -613,74 +614,6 @@
extern atomic_t tcp_sockets_allocated;
extern int tcp_memory_pressure;
-struct open_request;
-
-struct or_calltable {
- int family;
- int (*rtx_syn_ack) (struct sock *sk, struct open_request *req, struct dst_entry*);
- void (*send_ack) (struct sk_buff *skb, struct open_request *req);
- void (*destructor) (struct open_request *req);
- void (*send_reset) (struct sk_buff *skb);
-};
-
-struct tcp_v4_open_req {
- __u32 loc_addr;
- __u32 rmt_addr;
- struct ip_options *opt;
-};
-
-#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
-struct tcp_v6_open_req {
- struct in6_addr loc_addr;
- struct in6_addr rmt_addr;
- struct sk_buff *pktopts;
- int iif;
-};
-#endif
-
-/* this structure is too big */
-struct open_request {
- struct open_request *dl_next; /* Must be first member! */
- __u32 rcv_isn;
- __u32 snt_isn;
- __u16 rmt_port;
- __u16 mss;
- __u8 retrans;
- __u8 __pad;
- __u16 snd_wscale : 4,
- rcv_wscale : 4,
- tstamp_ok : 1,
- sack_ok : 1,
- wscale_ok : 1,
- ecn_ok : 1,
- acked : 1;
- /* The following two fields can be easily recomputed I think -AK */
- __u32 window_clamp; /* window clamp at creation time */
- __u32 rcv_wnd; /* rcv_wnd offered first time */
- __u32 ts_recent;
- unsigned long expires;
- struct or_calltable *class;
- struct sock *sk;
- union {
- struct tcp_v4_open_req v4_req;
-#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
- struct tcp_v6_open_req v6_req;
-#endif
- } af;
-};
-
-/* SLAB cache for open requests. */
-extern kmem_cache_t *tcp_openreq_cachep;
-
-#define tcp_openreq_alloc() kmem_cache_alloc(tcp_openreq_cachep, SLAB_ATOMIC)
-#define tcp_openreq_fastfree(req) kmem_cache_free(tcp_openreq_cachep, req)
-
-static inline void tcp_openreq_free(struct open_request *req)
-{
- req->class->destructor(req);
- tcp_openreq_fastfree(req);
-}
-
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
#define TCP_INET_FAMILY(fam) ((fam) == AF_INET)
#else
@@ -1832,17 +1765,19 @@
struct tcp_options_received *rx_opt,
struct sk_buff *skb)
{
+ struct inet_request_sock *ireq = inet_rsk(req);
+
req->rcv_wnd = 0; /* So that tcp_send_synack() knows! */
- req->rcv_isn = TCP_SKB_CB(skb)->seq;
+ tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq;
req->mss = rx_opt->mss_clamp;
req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0;
- req->tstamp_ok = rx_opt->tstamp_ok;
- req->sack_ok = rx_opt->sack_ok;
- req->snd_wscale = rx_opt->snd_wscale;
- req->wscale_ok = rx_opt->wscale_ok;
- req->acked = 0;
- req->ecn_ok = 0;
- req->rmt_port = skb->h.th->source;
+ ireq->tstamp_ok = rx_opt->tstamp_ok;
+ ireq->sack_ok = rx_opt->sack_ok;
+ ireq->snd_wscale = rx_opt->snd_wscale;
+ ireq->wscale_ok = rx_opt->wscale_ok;
+ ireq->acked = 0;
+ ireq->ecn_ok = 0;
+ ireq->rmt_port = skb->h.th->source;
}
extern void tcp_enter_memory_pressure(void);