diff options
| author | Alexey Dobriyan <adobriyan@gmail.com> | 2018-04-10 16:31:52 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-11 10:28:34 -0700 |
| commit | b4884f23331ae31e9ecb617956986c3b76ab9a91 (patch) | |
| tree | 2f25f7337f1aedbfed4fa18b1b26ffa208136544 /fs/proc/proc_net.c | |
| parent | c4219edf1de2af44fd98903f72f6e1ceb7f3c701 (diff) | |
proc: move "struct proc_dir_entry" into kmem cache
"struct proc_dir_entry" is variable sized because of 0-length trailing
array for name, however, because of SLAB padding allocations it is
possible to make "struct proc_dir_entry" fixed sized and allocate same
amount of memory.
It buys fine-grained debugging with poisoning and usercopy protection
which is not possible with kmalloc-* caches.
Currently, on 32-bit 91+ byte allocations go into kmalloc-128 and on
64-bit 147+ byte allocations go to kmalloc-192 anyway.
Additional memory is allocated only for 38/46+ byte long names which are
rare or may not even exist in the wild.
Link: http://lkml.kernel.org/r/20180223205504.GA17139@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/proc/proc_net.c')
| -rw-r--r-- | fs/proc/proc_net.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c index 68c06ae7888c..e5fe3d400737 100644 --- a/fs/proc/proc_net.c +++ b/fs/proc/proc_net.c @@ -192,7 +192,7 @@ static __net_init int proc_net_ns_init(struct net *net) int err; err = -ENOMEM; - netd = kzalloc(sizeof(*netd) + 4, GFP_KERNEL); + netd = kmem_cache_zalloc(proc_dir_entry_cache, GFP_KERNEL); if (!netd) goto out; @@ -201,6 +201,7 @@ static __net_init int proc_net_ns_init(struct net *net) netd->nlink = 2; netd->namelen = 3; netd->parent = &proc_root; + netd->name = netd->inline_name; memcpy(netd->name, "net", 4); uid = make_kuid(net->user_ns, 0); @@ -223,7 +224,7 @@ static __net_init int proc_net_ns_init(struct net *net) return 0; free_net: - kfree(netd); + pde_free(netd); out: return err; } @@ -231,7 +232,7 @@ out: static __net_exit void proc_net_ns_exit(struct net *net) { remove_proc_entry("stat", net->proc_net); - kfree(net->proc_net); + pde_free(net->proc_net); } static struct pernet_operations __net_initdata proc_net_ns_ops = { |