svn commit: r211413 - head/libexec/rtld-elf
Konstantin Belousov
kib at FreeBSD.org
Tue Aug 17 09:05:40 UTC 2010
Author: kib
Date: Tue Aug 17 09:05:39 2010
New Revision: 211413
URL: http://svn.freebsd.org/changeset/base/211413
Log:
Use the newly provided aux vectors to get pagesize and osreldate information.
Use local version of getpagesize(), rtld_getpagesize() in private allocator.
Override the __getosreldate() previously fetched from libc_pic.a with
local version that uses aux value if present. Note that __getosreldate()
is used by rtld indirectly, by mmap(2) libc wrapper.
To be able to utilize aux, split digest_dynamic() for use by init_rtld()
into two parts, where the first one does not call malloc(), and the
second part uses it. init_rtld() is able to initialize global variables
before digest_dynamic2() calls. In particular, pagesize and osreldate are
set up from the aux values.
Now, rtld avoids (two) sysctl calls in startup.
Tested by: marius (sparc64)
MFC after: 1 month
Modified:
head/libexec/rtld-elf/malloc.c
head/libexec/rtld-elf/rtld.c
Modified: head/libexec/rtld-elf/malloc.c
==============================================================================
--- head/libexec/rtld-elf/malloc.c Tue Aug 17 08:55:45 2010 (r211412)
+++ head/libexec/rtld-elf/malloc.c Tue Aug 17 09:05:39 2010 (r211413)
@@ -48,6 +48,7 @@ static char *rcsid = "$FreeBSD$";
*/
#include <sys/types.h>
+#include <sys/sysctl.h>
#include <err.h>
#include <paths.h>
#include <stdarg.h>
@@ -152,6 +153,26 @@ botch(s)
static void xprintf(const char *, ...);
#define TRACE() xprintf("TRACE %s:%d\n", __FILE__, __LINE__)
+extern int pagesize;
+
+static int
+rtld_getpagesize(void)
+{
+ int mib[2];
+ size_t size;
+
+ if (pagesize != 0)
+ return (pagesize);
+
+ mib[0] = CTL_HW;
+ mib[1] = HW_PAGESIZE;
+ size = sizeof(pagesize);
+ if (sysctl(mib, 2, &pagesize, &size, NULL, 0) == -1)
+ return (-1);
+ return (pagesize);
+
+}
+
void *
malloc(nbytes)
size_t nbytes;
@@ -166,7 +187,7 @@ malloc(nbytes)
* align break pointer so all data will be page aligned.
*/
if (pagesz == 0) {
- pagesz = n = getpagesize();
+ pagesz = n = rtld_getpagesize();
if (morepages(NPOOLPAGES) == 0)
return NULL;
op = (union overhead *)(pagepool_start);
Modified: head/libexec/rtld-elf/rtld.c
==============================================================================
--- head/libexec/rtld-elf/rtld.c Tue Aug 17 08:55:45 2010 (r211412)
+++ head/libexec/rtld-elf/rtld.c Tue Aug 17 09:05:39 2010 (r211413)
@@ -40,6 +40,7 @@
#include <sys/mount.h>
#include <sys/mman.h>
#include <sys/stat.h>
+#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/utsname.h>
#include <sys/ktrace.h>
@@ -84,6 +85,9 @@ typedef struct Struct_DoneList {
*/
static const char *basename(const char *);
static void die(void) __dead2;
+static void digest_dynamic1(Obj_Entry *, int, const Elf_Dyn **,
+ const Elf_Dyn **);
+static void digest_dynamic2(Obj_Entry *, const Elf_Dyn *, const Elf_Dyn *);
static void digest_dynamic(Obj_Entry *, int);
static Obj_Entry *digest_phdr(const Elf_Phdr *, int, caddr_t, const char *);
static Obj_Entry *dlcheck(void *);
@@ -97,7 +101,7 @@ static char *find_library(const char *,
static const char *gethints(void);
static void init_dag(Obj_Entry *);
static void init_dag1(Obj_Entry *, Obj_Entry *, DoneList *);
-static void init_rtld(caddr_t);
+static void init_rtld(caddr_t, Elf_Auxinfo **);
static void initlist_add_neededs(Needed_Entry *, Objlist *);
static void initlist_add_objects(Obj_Entry *, Obj_Entry **, Objlist *);
static bool is_exported(const Elf_Sym *);
@@ -188,6 +192,8 @@ extern Elf_Dyn _DYNAMIC;
#define RTLD_IS_DYNAMIC() (&_DYNAMIC != NULL)
#endif
+int osreldate, pagesize;
+
/*
* These are the functions the dynamic linker exports to application
* programs. They are the only symbols the dynamic linker is willing
@@ -350,7 +356,7 @@ _rtld(Elf_Addr *sp, func_ptr_type *exit_
/* Initialize and relocate ourselves. */
assert(aux_info[AT_BASE] != NULL);
- init_rtld((caddr_t) aux_info[AT_BASE]->a_un.a_ptr);
+ init_rtld((caddr_t) aux_info[AT_BASE]->a_un.a_ptr, aux_info);
__progname = obj_rtld.path;
argv0 = argv[0] != NULL ? argv[0] : "(null)";
@@ -737,14 +743,16 @@ die(void)
* information in its Obj_Entry structure.
*/
static void
-digest_dynamic(Obj_Entry *obj, int early)
+digest_dynamic1(Obj_Entry *obj, int early, const Elf_Dyn **dyn_rpath,
+ const Elf_Dyn **dyn_soname)
{
const Elf_Dyn *dynp;
Needed_Entry **needed_tail = &obj->needed;
- const Elf_Dyn *dyn_rpath = NULL;
- const Elf_Dyn *dyn_soname = NULL;
int plttype = DT_REL;
+ *dyn_rpath = NULL;
+ *dyn_soname = NULL;
+
obj->bind_now = false;
for (dynp = obj->dynamic; dynp->d_tag != DT_NULL; dynp++) {
switch (dynp->d_tag) {
@@ -868,11 +876,11 @@ digest_dynamic(Obj_Entry *obj, int early
* We have to wait until later to process this, because we
* might not have gotten the address of the string table yet.
*/
- dyn_rpath = dynp;
+ *dyn_rpath = dynp;
break;
case DT_SONAME:
- dyn_soname = dynp;
+ *dyn_soname = dynp;
break;
case DT_INIT:
@@ -961,6 +969,12 @@ digest_dynamic(Obj_Entry *obj, int early
obj->pltrelasize = obj->pltrelsize;
obj->pltrelsize = 0;
}
+}
+
+static void
+digest_dynamic2(Obj_Entry *obj, const Elf_Dyn *dyn_rpath,
+ const Elf_Dyn *dyn_soname)
+{
if (obj->z_origin && obj->origin_path == NULL) {
obj->origin_path = xmalloc(PATH_MAX);
@@ -978,6 +992,16 @@ digest_dynamic(Obj_Entry *obj, int early
object_add_name(obj, obj->strtab + dyn_soname->d_un.d_val);
}
+static void
+digest_dynamic(Obj_Entry *obj, int early)
+{
+ const Elf_Dyn *dyn_rpath;
+ const Elf_Dyn *dyn_soname;
+
+ digest_dynamic1(obj, early, &dyn_rpath, &dyn_soname);
+ digest_dynamic2(obj, dyn_rpath, dyn_soname);
+}
+
/*
* Process a shared object's program header. This is used only for the
* main program, when the kernel has already loaded the main program
@@ -1304,9 +1328,11 @@ init_dag1(Obj_Entry *root, Obj_Entry *ob
* this function is to relocate the dynamic linker.
*/
static void
-init_rtld(caddr_t mapbase)
+init_rtld(caddr_t mapbase, Elf_Auxinfo **aux_info)
{
Obj_Entry objtmp; /* Temporary rtld object */
+ const Elf_Dyn *dyn_rpath;
+ const Elf_Dyn *dyn_soname;
/*
* Conjure up an Obj_Entry structure for the dynamic linker.
@@ -1323,7 +1349,7 @@ init_rtld(caddr_t mapbase)
#endif
if (RTLD_IS_DYNAMIC()) {
objtmp.dynamic = rtld_dynamic(&objtmp);
- digest_dynamic(&objtmp, 1);
+ digest_dynamic1(&objtmp, 1, &dyn_rpath, &dyn_soname);
assert(objtmp.needed == NULL);
#if !defined(__mips__)
/* MIPS and SH{3,5} have a bogus DT_TEXTREL. */
@@ -1344,6 +1370,13 @@ init_rtld(caddr_t mapbase)
/* Now that non-local variables can be accesses, copy out obj_rtld. */
memcpy(&obj_rtld, &objtmp, sizeof(obj_rtld));
+ if (aux_info[AT_PAGESZ] != NULL)
+ pagesize = aux_info[AT_PAGESZ]->a_un.a_val;
+ if (aux_info[AT_OSRELDATE] != NULL)
+ osreldate = aux_info[AT_OSRELDATE]->a_un.a_val;
+
+ digest_dynamic2(&obj_rtld, dyn_rpath, dyn_soname);
+
/* Replace the path with a dynamically allocated copy. */
obj_rtld.path = xstrdup(PATH_RTLD);
@@ -3630,3 +3663,23 @@ fetch_ventry(const Obj_Entry *obj, unsig
}
return NULL;
}
+
+int
+__getosreldate(void)
+{
+ size_t len;
+ int oid[2];
+ int error, osrel;
+
+ if (osreldate != 0)
+ return (osreldate);
+
+ oid[0] = CTL_KERN;
+ oid[1] = KERN_OSRELDATE;
+ osrel = 0;
+ len = sizeof(osrel);
+ error = sysctl(oid, 2, &osrel, &len, NULL, 0);
+ if (error == 0 && osrel > 0 && len == sizeof(osrel))
+ osreldate = osrel;
+ return (osreldate);
+}
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