forked from Minki/linux
c7d03a00b5
Make struct pernet_operations::id unsigned.
There are 2 reasons to do so:
1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.
2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.
"int" being used as an array index needs to be sign-extended
to 64-bit before being used.
void f(long *p, int i)
{
g(p[i]);
}
roughly translates to
movsx rsi, esi
mov rdi, [rsi+...]
call g
MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.
Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:
static inline void *net_generic(const struct net *net, int id)
{
...
ptr = ng->ptr[id - 1];
...
}
And this function is used a lot, so those sign extensions add up.
Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):
add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]
However, overall balance is in negative direction:
add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
function old new delta
nfsd4_lock 3886 3959 +73
tipc_link_build_proto_msg 1096 1140 +44
mac80211_hwsim_new_radio 2776 2808 +32
tipc_mon_rcv 1032 1058 +26
svcauth_gss_legacy_init 1413 1429 +16
tipc_bcbase_select_primary 379 392 +13
nfsd4_exchange_id 1247 1260 +13
nfsd4_setclientid_confirm 782 793 +11
...
put_client_renew_locked 494 480 -14
ip_set_sockfn_get 730 716 -14
geneve_sock_add 829 813 -16
nfsd4_sequence_done 721 703 -18
nlmclnt_lookup_host 708 686 -22
nfsd4_lockt 1085 1063 -22
nfs_get_client 1077 1050 -27
tcf_bpf_init 1106 1076 -30
nfsd4_encode_fattr 5997 5930 -67
Total: Before=154856051, After=154854321, chg -0.00%
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
137 lines
2.6 KiB
C
137 lines
2.6 KiB
C
/*
|
|
* linux/net/sunrpc/sunrpc_syms.c
|
|
*
|
|
* Symbols exported by the sunrpc module.
|
|
*
|
|
* Copyright (C) 1997 Olaf Kirch <okir@monad.swb.de>
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/uio.h>
|
|
#include <linux/unistd.h>
|
|
#include <linux/init.h>
|
|
|
|
#include <linux/sunrpc/sched.h>
|
|
#include <linux/sunrpc/clnt.h>
|
|
#include <linux/sunrpc/svc.h>
|
|
#include <linux/sunrpc/svcsock.h>
|
|
#include <linux/sunrpc/auth.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/sunrpc/rpc_pipe_fs.h>
|
|
#include <linux/sunrpc/xprtsock.h>
|
|
|
|
#include "netns.h"
|
|
|
|
unsigned int sunrpc_net_id;
|
|
EXPORT_SYMBOL_GPL(sunrpc_net_id);
|
|
|
|
static __net_init int sunrpc_init_net(struct net *net)
|
|
{
|
|
int err;
|
|
struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
|
|
|
|
err = rpc_proc_init(net);
|
|
if (err)
|
|
goto err_proc;
|
|
|
|
err = ip_map_cache_create(net);
|
|
if (err)
|
|
goto err_ipmap;
|
|
|
|
err = unix_gid_cache_create(net);
|
|
if (err)
|
|
goto err_unixgid;
|
|
|
|
err = rpc_pipefs_init_net(net);
|
|
if (err)
|
|
goto err_pipefs;
|
|
|
|
INIT_LIST_HEAD(&sn->all_clients);
|
|
spin_lock_init(&sn->rpc_client_lock);
|
|
spin_lock_init(&sn->rpcb_clnt_lock);
|
|
return 0;
|
|
|
|
err_pipefs:
|
|
unix_gid_cache_destroy(net);
|
|
err_unixgid:
|
|
ip_map_cache_destroy(net);
|
|
err_ipmap:
|
|
rpc_proc_exit(net);
|
|
err_proc:
|
|
return err;
|
|
}
|
|
|
|
static __net_exit void sunrpc_exit_net(struct net *net)
|
|
{
|
|
rpc_pipefs_exit_net(net);
|
|
unix_gid_cache_destroy(net);
|
|
ip_map_cache_destroy(net);
|
|
rpc_proc_exit(net);
|
|
}
|
|
|
|
static struct pernet_operations sunrpc_net_ops = {
|
|
.init = sunrpc_init_net,
|
|
.exit = sunrpc_exit_net,
|
|
.id = &sunrpc_net_id,
|
|
.size = sizeof(struct sunrpc_net),
|
|
};
|
|
|
|
static int __init
|
|
init_sunrpc(void)
|
|
{
|
|
int err = rpc_init_mempool();
|
|
if (err)
|
|
goto out;
|
|
err = rpcauth_init_module();
|
|
if (err)
|
|
goto out2;
|
|
|
|
cache_initialize();
|
|
|
|
err = register_pernet_subsys(&sunrpc_net_ops);
|
|
if (err)
|
|
goto out3;
|
|
|
|
err = register_rpc_pipefs();
|
|
if (err)
|
|
goto out4;
|
|
|
|
sunrpc_debugfs_init();
|
|
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
|
|
rpc_register_sysctl();
|
|
#endif
|
|
svc_init_xprt_sock(); /* svc sock transport */
|
|
init_socket_xprt(); /* clnt sock transport */
|
|
return 0;
|
|
|
|
out4:
|
|
unregister_pernet_subsys(&sunrpc_net_ops);
|
|
out3:
|
|
rpcauth_remove_module();
|
|
out2:
|
|
rpc_destroy_mempool();
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void __exit
|
|
cleanup_sunrpc(void)
|
|
{
|
|
rpcauth_remove_module();
|
|
cleanup_socket_xprt();
|
|
svc_cleanup_xprt_sock();
|
|
sunrpc_debugfs_exit();
|
|
unregister_rpc_pipefs();
|
|
rpc_destroy_mempool();
|
|
unregister_pernet_subsys(&sunrpc_net_ops);
|
|
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
|
|
rpc_unregister_sysctl();
|
|
#endif
|
|
rcu_barrier(); /* Wait for completion of call_rcu()'s */
|
|
}
|
|
MODULE_LICENSE("GPL");
|
|
fs_initcall(init_sunrpc); /* Ensure we're initialised before nfs */
|
|
module_exit(cleanup_sunrpc);
|