[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/net/core/sock.c b/net/core/sock.c
index 96e00b0..a6ec3ad 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -118,6 +118,7 @@
#include <linux/netdevice.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
+#include <net/request_sock.h>
#include <net/sock.h>
#include <net/xfrm.h>
#include <linux/ipsec.h>
@@ -1363,6 +1364,7 @@
int proto_register(struct proto *prot, int alloc_slab)
{
+ char *request_sock_slab_name;
int rc = -ENOBUFS;
if (alloc_slab) {
@@ -1374,6 +1376,25 @@
prot->name);
goto out;
}
+
+ if (prot->rsk_prot != NULL) {
+ static const char mask[] = "request_sock_%s";
+
+ request_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
+ if (request_sock_slab_name == NULL)
+ goto out_free_sock_slab;
+
+ sprintf(request_sock_slab_name, mask, prot->name);
+ prot->rsk_prot->slab = kmem_cache_create(request_sock_slab_name,
+ prot->rsk_prot->obj_size, 0,
+ SLAB_HWCACHE_ALIGN, NULL, NULL);
+
+ if (prot->rsk_prot->slab == NULL) {
+ printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
+ prot->name);
+ goto out_free_request_sock_slab_name;
+ }
+ }
}
write_lock(&proto_list_lock);
@@ -1382,6 +1403,12 @@
rc = 0;
out:
return rc;
+out_free_request_sock_slab_name:
+ kfree(request_sock_slab_name);
+out_free_sock_slab:
+ kmem_cache_destroy(prot->slab);
+ prot->slab = NULL;
+ goto out;
}
EXPORT_SYMBOL(proto_register);
@@ -1395,6 +1422,14 @@
prot->slab = NULL;
}
+ if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
+ const char *name = kmem_cache_name(prot->rsk_prot->slab);
+
+ kmem_cache_destroy(prot->rsk_prot->slab);
+ kfree(name);
+ prot->rsk_prot->slab = NULL;
+ }
+
list_del(&prot->node);
write_unlock(&proto_list_lock);
}
