1998-11-22 Roland McGrath <roland@baalperazim.frob.com>

* sysdeps/mach/hurd/i386/init-first.c (init): Provide temporary storage 
for the per-thread variables of the main user thread to make it 
possible to use malloc as soon as _hurd_preinit_hook has been run. 
For cthreads, copy values to new stack from there. 
For non-cthreads, malloc threadvar array here and copy from temp space. 
(init1): No longer initialize threadvars here. 
(doinit1): Made static void at top level. 
(init): Folded into [PIC] _init or [!PIC] doinit1, since GCC cannot 
inline a function that uses dynamic auto arrays.
This commit is contained in:
Roland McGrath 1998-11-22 17:32:14 +00:00
parent b17f830fe1
commit 54509b04ce
1 changed files with 126 additions and 109 deletions

View File

@ -105,20 +105,6 @@ init1 (int argc, char *arg0, ...)
}
}
if (__hurd_threadvar_stack_mask == 0)
{
/* We are not using cthreads, so we will have just a single allocated
area for the per-thread variables of the main user thread. */
unsigned long int i;
__hurd_threadvar_stack_offset
= (unsigned long int) malloc (__hurd_threadvar_max *
sizeof (unsigned long int));
if (__hurd_threadvar_stack_offset == 0)
__libc_fatal ("Can't allocate single-threaded per-thread variables.");
for (i = 0; i < __hurd_threadvar_max; ++i)
((unsigned long int *) __hurd_threadvar_stack_offset)[i] = 0;
}
if ((void *) d != argv[0] && (d->portarray || d->intarray))
/* Initialize library data structures, start signal processing, etc. */
_hurd_init (d->flags, argv,
@ -133,14 +119,48 @@ init1 (int argc, char *arg0, ...)
}
static inline void
init (int *data)
#ifdef PIC
/* This function is called to initialize the shared C library.
It is called just before the user _start code from i386/elf/start.S,
with the stack set up as that code gets it. */
/* NOTE! The linker notices the magical name `_init' and sets the DT_INIT
pointer in the dynamic section based solely on that. It is convention
for this function to be in the `.init' section, but the symbol name is
the only thing that really matters!! */
void
_init (int argc, ...)
{
int argc = *data;
/* Initialize data structures so we can do RPCs. */
__mach_init ();
RUN_HOOK (_hurd_preinit_hook, ());
#else
/* In statically-linked programs, this function is
called from _hurd_stack_setup (below). */
static void
doinit1 (int argc, ...)
{
#endif
/* This block used to be a separate inline function.
But GCC refuses to inline a function that uses alloca
or dynamically-sized auto arrays. */
{
int *const data = &argc;
char **argv = (void *) (data + 1);
char **envp = &argv[argc + 1];
struct hurd_startup_data *d;
unsigned long int threadvars[__hurd_threadvar_max];
/* Provide temporary storage for thread-specific variables on the startup
stack so the cthreads initialization code can use them for malloc et al,
or so we can use malloc below for the real threadvars array. */
memset (threadvars, 0, sizeof threadvars);
__hurd_threadvar_stack_offset = (unsigned long int) threadvars;
__environ = envp;
while (*envp)
++envp;
@ -160,10 +180,18 @@ init (int *data)
if (_cthread_init_routine)
{
/* Initialize cthreads, which will allocate us a new stack to run on. */
void *newsp = (*_cthread_init_routine) ();
void *newsp;
struct hurd_startup_data *od;
/* Initialize cthreads, which will allocate us a new
stack to run on. */
newsp = (*_cthread_init_routine) ();
/* Copy per-thread variables from that temporary
area onto the new cthread stack. */
memcpy (__hurd_threadvar_location_from_sp (0, newsp),
threadvars, sizeof threadvars);
/* Copy the argdata from the old stack to the new one. */
newsp = memcpy (newsp - ((char *) &d[1] - (char *) data), data,
(char *) d - (char *) data);
@ -190,9 +218,23 @@ init (int *data)
}
else
{
/* We are not using cthreads, so we will have just a single allocated
area for the per-thread variables of the main user thread. */
void *array;
int usercode;
array = malloc (sizeof threadvars);
if (array == NULL)
__libc_fatal ("Can't allocate single-threaded thread variables.");
/* Copy per-thread variables from the temporary array into the
newly malloc'd space. */
memcpy (array, threadvars, sizeof threadvars);
__hurd_threadvar_stack_offset = (unsigned long int) array;
/* The argument data is just above the stack frame we will unwind by
returning. Mutate our own return address to run the code below. */
int usercode = data[-1];
usercode = data[-1];
((void **) data)[-1] = &&call_init1;
/* Force USERCODE into %eax and &init1 into %ecx, which are not
restored by function return. */
@ -202,48 +244,27 @@ init (int *data)
return;
switch_stacks:
/* Our return address was redirected to here, so at this point our stack
is unwound and callers' registers restored. Only %ecx and %eax are
call-clobbered and thus still have the values we set just above.
Fetch from there the new stack pointer we will run on, and jmp to the
run-time address of `init1'; when it returns, it will run the user
code with the argument data at the top of the stack. */
/* Our return address was redirected to here, so at this point our
stack is unwound and callers' registers restored. Only %ecx and
%eax are call-clobbered and thus still have the values we set just
above. Fetch from there the new stack pointer we will run on, and
jmp to the run-time address of `init1'; when it returns, it will run
the user code with the argument data at the top of the stack. */
asm volatile ("movl %eax, %esp; jmp *%ecx");
/* NOTREACHED */
call_init1:
/* As in the stack-switching case, at this point our stack is unwound and
callers' registers restored, and only %ecx and %eax communicate values
from the lines above. In this case we have stashed in %eax the user
code return address. Push it on the top of the stack so it acts as
init1's return address, and then jump there. */
/* As in the stack-switching case, at this point our stack is unwound
and callers' registers restored, and only %ecx and %eax communicate
values from the lines above. In this case we have stashed in %eax
the user code return address. Push it on the top of the stack so it
acts as init1's return address, and then jump there. */
asm volatile ("pushl %eax; jmp *%ecx");
/* NOTREACHED */
}
}
#ifdef PIC
/* This function is called to initialize the shared C library.
It is called just before the user _start code from i386/elf/start.S,
with the stack set up as that code gets it. */
/* NOTE! The linker notices the magical name `_init' and sets the DT_INIT
pointer in the dynamic section based solely on that. It is convention
for this function to be in the `.init' section, but the symbol name is
the only thing that really matters!! */
void
_init (int argc, ...)
{
/* Initialize data structures so we can do RPCs. */
__mach_init ();
RUN_HOOK (_hurd_preinit_hook, ());
init (&argc);
}
#endif
void
__libc_init_first (int argc, char **argv, char **envp)
#ifdef PIC
@ -264,10 +285,6 @@ _hurd_stack_setup (int argc __attribute__ ((unused)), ...)
void doinit (int *data)
{
/* This function gets called with the argument data at TOS. */
void doinit1 (int argc, ...)
{
init (&argc);
}
/* Push the user return address after the argument data, and then
jump to `doinit1' (above), so it is as if __libc_init_first's