Add a 'SINGLETON' directive to kobj interface definition

Summary:
This makes the interface described in the definition file act like a
pseudo-IFUNC service, by caching the found method locally.

Applying this to the PowerPC MMU definitions, it yields a significant
(15-20%) performance improvement, seen in both a 'make buildworld' and a
parallel build of LLVM, on a POWER9 system.

Reviewed By:	imp
Differential Revision:	https://reviews.freebsd.org/D23245
This commit is contained in:
Justin Hibbits 2020-01-18 02:39:38 +00:00
parent 2d0c620272
commit de8dd262c4
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=356860
3 changed files with 11 additions and 1 deletions

View File

@ -43,6 +43,7 @@
*/
INTERFACE moea64;
SINGLETON;
CODE {
static moea64_pte_replace_t moea64_pte_replace_default;

View File

@ -46,6 +46,7 @@
*/
INTERFACE mmu;
SINGLETON;
#
# Default implementations of some methods

View File

@ -325,13 +325,18 @@ function handle_method (static, doc)
line_width, length(prototype)));
}
printh("{");
printh("\tkobjop_t _m;");
if (singleton)
printh("\tstatic kobjop_t _m;");
else
printh("\tkobjop_t _m;");
if (ret != "void")
printh("\t" ret " rc;");
if (!static)
firstvar = "((kobj_t)" firstvar ")";
if (prolog != "")
printh(prolog);
if (singleton)
printh("\tif (_m == NULL)");
printh("\tKOBJOPLOOKUP(" firstvar "->ops," mname ");");
rceq = (ret != "void") ? "rc = " : "";
printh("\t" rceq "((" mname "_t *) _m)(" varname_list ");");
@ -453,6 +458,7 @@ for (file_i = 0; file_i < num_files; file_i++) {
lastdoc = "";
prolog = "";
epilog = "";
singleton = 0;
while (!error && (getline < src) > 0) {
lineno++;
@ -497,6 +503,8 @@ for (file_i = 0; file_i < num_files; file_i++) {
prolog = handle_code();
else if (/^EPILOG[ ]*{$/)
epilog = handle_code();
else if (/^SINGLETON/)
singleton = 1;
else {
debug($0);
warnsrc("Invalid line encountered");