Module Name: src
Committed By: joerg
Date: Mon Apr 5 14:01:26 UTC 2010
Modified Files:
src/libexec/ld.elf_so: headers.c reloc.c rtld.h symbol.c
Log Message:
Use fast_remainder32 for the ELF hash. For the hot cache case, this
speeds up Firefox startup by over 2% on AMD64.
Limit hash table buckets to 32bit.
To generate a diff of this commit:
cvs rdiff -u -r1.28 -r1.29 src/libexec/ld.elf_so/headers.c
cvs rdiff -u -r1.101 -r1.102 src/libexec/ld.elf_so/reloc.c
cvs rdiff -u -r1.90 -r1.91 src/libexec/ld.elf_so/rtld.h
cvs rdiff -u -r1.52 -r1.53 src/libexec/ld.elf_so/symbol.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/libexec/ld.elf_so/headers.c
diff -u src/libexec/ld.elf_so/headers.c:1.28 src/libexec/ld.elf_so/headers.c:1.29
--- src/libexec/ld.elf_so/headers.c:1.28 Sun Apr 12 13:29:29 2009
+++ src/libexec/ld.elf_so/headers.c Mon Apr 5 14:01:26 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: headers.c,v 1.28 2009/04/12 13:29:29 lukem Exp $ */
+/* $NetBSD: headers.c,v 1.29 2010/04/05 14:01:26 joerg Exp $ */
/*
* Copyright 1996 John D. Polstra.
@@ -40,7 +40,7 @@
#include <sys/cdefs.h>
#ifndef lint
-__RCSID("$NetBSD: headers.c,v 1.28 2009/04/12 13:29:29 lukem Exp $");
+__RCSID("$NetBSD: headers.c,v 1.29 2010/04/05 14:01:26 joerg Exp $");
#endif /* not lint */
#include <err.h>
@@ -53,6 +53,7 @@
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
+#include <sys/bitops.h>
#include <dirent.h>
#include "debug.h"
@@ -138,10 +139,23 @@
const Elf_Word *hashtab = (const Elf_Word *)
(obj->relocbase + dynp->d_un.d_ptr);
- obj->nbuckets = hashtab[0];
+ if (hashtab[0] > UINT32_MAX)
+ obj->nbuckets = UINT32_MAX;
+ else
+ obj->nbuckets = hashtab[0];
obj->nchains = hashtab[1];
obj->buckets = hashtab + 2;
obj->chains = obj->buckets + obj->nbuckets;
+ /*
+ * Should really be in _rtld_relocate_objects,
+ * but _rtld_symlook_obj might be used before.
+ */
+ if (obj->nbuckets) {
+ fast_divide32_prepare(obj->nbuckets,
+ &obj->nbuckets_m,
+ &obj->nbuckets_s1,
+ &obj->nbuckets_s2);
+ }
}
break;
Index: src/libexec/ld.elf_so/reloc.c
diff -u src/libexec/ld.elf_so/reloc.c:1.101 src/libexec/ld.elf_so/reloc.c:1.102
--- src/libexec/ld.elf_so/reloc.c:1.101 Sat Jan 16 10:37:51 2010
+++ src/libexec/ld.elf_so/reloc.c Mon Apr 5 14:01:26 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: reloc.c,v 1.101 2010/01/16 10:37:51 skrll Exp $ */
+/* $NetBSD: reloc.c,v 1.102 2010/04/05 14:01:26 joerg Exp $ */
/*
* Copyright 1996 John D. Polstra.
@@ -39,7 +39,7 @@
#include <sys/cdefs.h>
#ifndef lint
-__RCSID("$NetBSD: reloc.c,v 1.101 2010/01/16 10:37:51 skrll Exp $");
+__RCSID("$NetBSD: reloc.c,v 1.102 2010/04/05 14:01:26 joerg Exp $");
#endif /* not lint */
#include <err.h>
@@ -52,6 +52,7 @@
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
+#include <sys/bitops.h>
#include <dirent.h>
#include "debug.h"
@@ -154,6 +155,10 @@
" symbol table", obj->path);
return -1;
}
+ if (obj->nbuckets == UINT32_MAX) {
+ _rtld_error("%s: Symbol table too large", obj->path);
+ return -1;
+ }
rdbg((" relocating %s (%ld/%ld rel/rela, %ld/%ld plt rel/rela)",
obj->path,
(long)(obj->rellim - obj->rel),
Index: src/libexec/ld.elf_so/rtld.h
diff -u src/libexec/ld.elf_so/rtld.h:1.90 src/libexec/ld.elf_so/rtld.h:1.91
--- src/libexec/ld.elf_so/rtld.h:1.90 Thu Mar 18 22:17:55 2010
+++ src/libexec/ld.elf_so/rtld.h Mon Apr 5 14:01:26 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: rtld.h,v 1.90 2010/03/18 22:17:55 roy Exp $ */
+/* $NetBSD: rtld.h,v 1.91 2010/04/05 14:01:26 joerg Exp $ */
/*
* Copyright 1996 John D. Polstra.
@@ -162,7 +162,10 @@
#endif
const Elf_Word *buckets; /* Hash table buckets array */
- unsigned long nbuckets; /* Number of buckets */
+ uint32_t nbuckets; /* Number of buckets */
+ uint32_t nbuckets_m; /* Precomputed for fast remainder */
+ uint8_t nbuckets_s1;
+ uint8_t nbuckets_s2;
const Elf_Word *chains; /* Hash table chain array */
unsigned long nchains; /* Number of chains */
Index: src/libexec/ld.elf_so/symbol.c
diff -u src/libexec/ld.elf_so/symbol.c:1.52 src/libexec/ld.elf_so/symbol.c:1.53
--- src/libexec/ld.elf_so/symbol.c:1.52 Thu Mar 18 22:17:55 2010
+++ src/libexec/ld.elf_so/symbol.c Mon Apr 5 14:01:26 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: symbol.c,v 1.52 2010/03/18 22:17:55 roy Exp $ */
+/* $NetBSD: symbol.c,v 1.53 2010/04/05 14:01:26 joerg Exp $ */
/*
* Copyright 1996 John D. Polstra.
@@ -40,7 +40,7 @@
#include <sys/cdefs.h>
#ifndef lint
-__RCSID("$NetBSD: symbol.c,v 1.52 2010/03/18 22:17:55 roy Exp $");
+__RCSID("$NetBSD: symbol.c,v 1.53 2010/04/05 14:01:26 joerg Exp $");
#endif /* not lint */
#include <err.h>
@@ -53,6 +53,7 @@
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
+#include <sys/bitops.h>
#include <dirent.h>
#include "debug.h"
@@ -229,7 +230,8 @@
{
unsigned long symnum;
- for (symnum = obj->buckets[hash % obj->nbuckets];
+ for (symnum = obj->buckets[fast_remainder32(hash, obj->nbuckets,
+ obj->nbuckets_m, obj->nbuckets_s1, obj->nbuckets_s2)];
symnum != ELF_SYM_UNDEFINED;
symnum = obj->chains[symnum]) {
const Elf_Sym *symp;
