linux/security/selinux/ss
Waiman Long a767f680e3 SELinux: Increase ebitmap_node size for 64-bit configuration
Currently, the ebitmap_node structure has a fixed size of 32 bytes. On
a 32-bit system, the overhead is 8 bytes, leaving 24 bytes for being
used as bitmaps. The overhead ratio is 1/4.

On a 64-bit system, the overhead is 16 bytes. Therefore, only 16 bytes
are left for bitmap purpose and the overhead ratio is 1/2. With a
3.8.2 kernel, a boot-up operation will cause the ebitmap_get_bit()
function to be called about 9 million times. The average number of
ebitmap_node traversal is about 3.7.

This patch increases the size of the ebitmap_node structure to 64
bytes for 64-bit system to keep the overhead ratio at 1/4. This may
also improve performance a little bit by making node to node traversal
less frequent (< 2) as more bits are available in each node.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2013-07-25 13:02:31 -04:00
..
avtab.c SELinux: allow userspace to read policy back out of the kernel 2010-10-21 10:12:58 +11:00
avtab.h SELinux: Use dentry name in new object labeling 2011-02-01 11:12:30 -05:00
conditional.c selinux: Casting (void *) value returned by kmalloc is useless 2011-12-19 11:23:56 +11:00
conditional.h selinux: sparse fix: fix several warnings in the security server code 2011-09-09 16:56:32 -07:00
constraint.h
context.h SELinux: allow default source/target selectors for user/role/range 2012-04-09 12:22:47 -04:00
ebitmap.c SELinux: Reduce overhead of mls_level_isvalid() function call 2013-07-25 13:02:18 -04:00
ebitmap.h SELinux: Increase ebitmap_node size for 64-bit configuration 2013-07-25 13:02:31 -04:00
hashtab.c selinux: Unify for- and while-loop style 2008-08-15 08:40:47 +10:00
hashtab.h SELinux: hashtab.h whitespace, syntax, and other cleanups 2008-04-28 09:29:04 +10:00
mls_types.h SELinux: Reduce overhead of mls_level_isvalid() function call 2013-07-25 13:02:18 -04:00
mls.c SELinux: Reduce overhead of mls_level_isvalid() function call 2013-07-25 13:02:18 -04:00
mls.h doc: Update the email address for Paul Moore in various source files 2011-08-01 17:58:33 -07:00
policydb.c SELinux: add default_type statements 2012-04-09 12:22:48 -04:00
policydb.h SELinux: add default_type statements 2012-04-09 12:22:48 -04:00
services.c userns: Convert selinux to use kuid and kgid where appropriate 2012-09-21 03:13:22 -07:00
services.h
sidtab.c selinux: cache sidtab_context_to_sid results 2010-12-07 16:44:01 -05:00
sidtab.h selinux: cache sidtab_context_to_sid results 2010-12-07 16:44:01 -05:00
status.c selinux: fix up style problem on /selinux/status 2010-10-21 10:12:41 +11:00
symtab.c selinux: fix error codes in symtab_init() 2010-08-02 15:35:04 +10:00
symtab.h