linux/arch/sparc/kernel/process_32.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

710 lines
19 KiB
C

/* linux/arch/sparc/kernel/process.c
*
* Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
* Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
*/
/*
* This file handles the architecture-dependent parts of process handling..
*/
#include <stdarg.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <asm/auxio.h>
#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/delay.h>
#include <asm/processor.h>
#include <asm/psr.h>
#include <asm/elf.h>
#include <asm/prom.h>
#include <asm/unistd.h>
/*
* Power management idle function
* Set in pm platform drivers (apc.c and pmc.c)
*/
void (*pm_idle)(void);
EXPORT_SYMBOL(pm_idle);
/*
* Power-off handler instantiation for pm.h compliance
* This is done via auxio, but could be used as a fallback
* handler when auxio is not present-- unused for now...
*/
void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);
/*
* sysctl - toggle power-off restriction for serial console
* systems in machine_power_off()
*/
int scons_pwroff = 1;
extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);
struct task_struct *last_task_used_math = NULL;
struct thread_info *current_set[NR_CPUS];
#ifndef CONFIG_SMP
#define SUN4C_FAULT_HIGH 100
/*
* the idle loop on a Sparc... ;)
*/
void cpu_idle(void)
{
/* endless idle loop with no priority at all */
for (;;) {
if (ARCH_SUN4C) {
static int count = HZ;
static unsigned long last_jiffies;
static unsigned long last_faults;
static unsigned long fps;
unsigned long now;
unsigned long faults;
extern unsigned long sun4c_kernel_faults;
extern void sun4c_grow_kernel_ring(void);
local_irq_disable();
now = jiffies;
count -= (now - last_jiffies);
last_jiffies = now;
if (count < 0) {
count += HZ;
faults = sun4c_kernel_faults;
fps = (fps + (faults - last_faults)) >> 1;
last_faults = faults;
#if 0
printk("kernel faults / second = %ld\n", fps);
#endif
if (fps >= SUN4C_FAULT_HIGH) {
sun4c_grow_kernel_ring();
}
}
local_irq_enable();
}
if (pm_idle) {
while (!need_resched())
(*pm_idle)();
} else {
while (!need_resched())
cpu_relax();
}
preempt_enable_no_resched();
schedule();
preempt_disable();
check_pgt_cache();
}
}
#else
/* This is being executed in task 0 'user space'. */
void cpu_idle(void)
{
set_thread_flag(TIF_POLLING_NRFLAG);
/* endless idle loop with no priority at all */
while(1) {
while (!need_resched())
cpu_relax();
preempt_enable_no_resched();
schedule();
preempt_disable();
check_pgt_cache();
}
}
#endif
/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
void machine_halt(void)
{
local_irq_enable();
mdelay(8);
local_irq_disable();
prom_halt();
panic("Halt failed!");
}
void machine_restart(char * cmd)
{
char *p;
local_irq_enable();
mdelay(8);
local_irq_disable();
p = strchr (reboot_command, '\n');
if (p) *p = 0;
if (cmd)
prom_reboot(cmd);
if (*reboot_command)
prom_reboot(reboot_command);
prom_feval ("reset");
panic("Reboot failed!");
}
void machine_power_off(void)
{
if (auxio_power_register &&
(strcmp(of_console_device->type, "serial") || scons_pwroff))
*auxio_power_register |= AUXIO_POWER_OFF;
machine_halt();
}
#if 0
static DEFINE_SPINLOCK(sparc_backtrace_lock);
void __show_backtrace(unsigned long fp)
{
struct reg_window32 *rw;
unsigned long flags;
int cpu = smp_processor_id();
spin_lock_irqsave(&sparc_backtrace_lock, flags);
rw = (struct reg_window32 *)fp;
while(rw && (((unsigned long) rw) >= PAGE_OFFSET) &&
!(((unsigned long) rw) & 0x7)) {
printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] "
"FP[%08lx] CALLER[%08lx]: ", cpu,
rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
rw->ins[4], rw->ins[5],
rw->ins[6],
rw->ins[7]);
printk("%pS\n", (void *) rw->ins[7]);
rw = (struct reg_window32 *) rw->ins[6];
}
spin_unlock_irqrestore(&sparc_backtrace_lock, flags);
}
#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
#define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp))
void show_backtrace(void)
{
unsigned long fp;
__SAVE; __SAVE; __SAVE; __SAVE;
__SAVE; __SAVE; __SAVE; __SAVE;
__RESTORE; __RESTORE; __RESTORE; __RESTORE;
__RESTORE; __RESTORE; __RESTORE; __RESTORE;
__GET_FP(fp);
__show_backtrace(fp);
}
#ifdef CONFIG_SMP
void smp_show_backtrace_all_cpus(void)
{
xc0((smpfunc_t) show_backtrace);
show_backtrace();
}
#endif
void show_stackframe(struct sparc_stackf *sf)
{
unsigned long size;
unsigned long *stk;
int i;
printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx "
"l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n",
sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx "
"i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n",
sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx "
"x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n",
(unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
sf->xxargs[0]);
size = ((unsigned long)sf->fp) - ((unsigned long)sf);
size -= STACKFRAME_SZ;
stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
i = 0;
do {
printk("s%d: %08lx\n", i++, *stk++);
} while ((size -= sizeof(unsigned long)));
}
#endif
void show_regs(struct pt_regs *r)
{
struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14];
printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
r->psr, r->pc, r->npc, r->y, print_tainted());
printk("PC: <%pS>\n", (void *) r->pc);
printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
printk("RPC: <%pS>\n", (void *) r->u_regs[15]);
printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
}
/*
* The show_stack is an external API which we do not use ourselves.
* The oops is printed in die_if_kernel.
*/
void show_stack(struct task_struct *tsk, unsigned long *_ksp)
{
unsigned long pc, fp;
unsigned long task_base;
struct reg_window32 *rw;
int count = 0;
if (tsk != NULL)
task_base = (unsigned long) task_stack_page(tsk);
else
task_base = (unsigned long) current_thread_info();
fp = (unsigned long) _ksp;
do {
/* Bogus frame pointer? */
if (fp < (task_base + sizeof(struct thread_info)) ||
fp >= (task_base + (PAGE_SIZE << 1)))
break;
rw = (struct reg_window32 *) fp;
pc = rw->ins[7];
printk("[%08lx : ", pc);
printk("%pS ] ", (void *) pc);
fp = rw->ins[6];
} while (++count < 16);
printk("\n");
}
void dump_stack(void)
{
unsigned long *ksp;
__asm__ __volatile__("mov %%fp, %0"
: "=r" (ksp));
show_stack(current, ksp);
}
EXPORT_SYMBOL(dump_stack);
/*
* Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
*/
unsigned long thread_saved_pc(struct task_struct *tsk)
{
return task_thread_info(tsk)->kpc;
}
/*
* Free current thread data structures etc..
*/
void exit_thread(void)
{
#ifndef CONFIG_SMP
if(last_task_used_math == current) {
#else
if (test_thread_flag(TIF_USEDFPU)) {
#endif
/* Keep process from leaving FPU in a bogon state. */
put_psr(get_psr() | PSR_EF);
fpsave(&current->thread.float_regs[0], &current->thread.fsr,
&current->thread.fpqueue[0], &current->thread.fpqdepth);
#ifndef CONFIG_SMP
last_task_used_math = NULL;
#else
clear_thread_flag(TIF_USEDFPU);
#endif
}
}
void flush_thread(void)
{
current_thread_info()->w_saved = 0;
#ifndef CONFIG_SMP
if(last_task_used_math == current) {
#else
if (test_thread_flag(TIF_USEDFPU)) {
#endif
/* Clean the fpu. */
put_psr(get_psr() | PSR_EF);
fpsave(&current->thread.float_regs[0], &current->thread.fsr,
&current->thread.fpqueue[0], &current->thread.fpqdepth);
#ifndef CONFIG_SMP
last_task_used_math = NULL;
#else
clear_thread_flag(TIF_USEDFPU);
#endif
}
/* Now, this task is no longer a kernel thread. */
current->thread.current_ds = USER_DS;
if (current->thread.flags & SPARC_FLAG_KTHREAD) {
current->thread.flags &= ~SPARC_FLAG_KTHREAD;
/* We must fixup kregs as well. */
/* XXX This was not fixed for ti for a while, worked. Unused? */
current->thread.kregs = (struct pt_regs *)
(task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
}
}
static inline struct sparc_stackf __user *
clone_stackframe(struct sparc_stackf __user *dst,
struct sparc_stackf __user *src)
{
unsigned long size, fp;
struct sparc_stackf *tmp;
struct sparc_stackf __user *sp;
if (get_user(tmp, &src->fp))
return NULL;
fp = (unsigned long) tmp;
size = (fp - ((unsigned long) src));
fp = (unsigned long) dst;
sp = (struct sparc_stackf __user *)(fp - size);
/* do_fork() grabs the parent semaphore, we must release it
* temporarily so we can build the child clone stack frame
* without deadlocking.
*/
if (__copy_user(sp, src, size))
sp = NULL;
else if (put_user(fp, &sp->fp))
sp = NULL;
return sp;
}
asmlinkage int sparc_do_fork(unsigned long clone_flags,
unsigned long stack_start,
struct pt_regs *regs,
unsigned long stack_size)
{
unsigned long parent_tid_ptr, child_tid_ptr;
unsigned long orig_i1 = regs->u_regs[UREG_I1];
long ret;
parent_tid_ptr = regs->u_regs[UREG_I2];
child_tid_ptr = regs->u_regs[UREG_I4];
ret = do_fork(clone_flags, stack_start,
regs, stack_size,
(int __user *) parent_tid_ptr,
(int __user *) child_tid_ptr);
/* If we get an error and potentially restart the system
* call, we're screwed because copy_thread() clobbered
* the parent's %o1. So detect that case and restore it
* here.
*/
if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
regs->u_regs[UREG_I1] = orig_i1;
return ret;
}
/* Copy a Sparc thread. The fork() return value conventions
* under SunOS are nothing short of bletcherous:
* Parent --> %o0 == childs pid, %o1 == 0
* Child --> %o0 == parents pid, %o1 == 1
*
* NOTE: We have a separate fork kpsr/kwim because
* the parent could change these values between
* sys_fork invocation and when we reach here
* if the parent should sleep while trying to
* allocate the task_struct and kernel stack in
* do_fork().
* XXX See comment above sys_vfork in sparc64. todo.
*/
extern void ret_from_fork(void);
int copy_thread(unsigned long clone_flags, unsigned long sp,
unsigned long unused,
struct task_struct *p, struct pt_regs *regs)
{
struct thread_info *ti = task_thread_info(p);
struct pt_regs *childregs;
char *new_stack;
#ifndef CONFIG_SMP
if(last_task_used_math == current) {
#else
if (test_thread_flag(TIF_USEDFPU)) {
#endif
put_psr(get_psr() | PSR_EF);
fpsave(&p->thread.float_regs[0], &p->thread.fsr,
&p->thread.fpqueue[0], &p->thread.fpqdepth);
#ifdef CONFIG_SMP
clear_thread_flag(TIF_USEDFPU);
#endif
}
/*
* p->thread_info new_stack childregs
* ! ! ! {if(PSR_PS) }
* V V (stk.fr.) V (pt_regs) { (stk.fr.) }
* +----- - - - - - ------+===========+============={+==========}+
*/
new_stack = task_stack_page(p) + THREAD_SIZE;
if (regs->psr & PSR_PS)
new_stack -= STACKFRAME_SZ;
new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
/*
* A new process must start with interrupts closed in 2.5,
* because this is how Mingo's scheduler works (see schedule_tail
* and finish_arch_switch). If we do not do it, a timer interrupt hits
* before we unlock, attempts to re-take the rq->lock, and then we die.
* Thus, kpsr|=PSR_PIL.
*/
ti->ksp = (unsigned long) new_stack;
ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
ti->kwim = current->thread.fork_kwim;
if(regs->psr & PSR_PS) {
extern struct pt_regs fake_swapper_regs;
p->thread.kregs = &fake_swapper_regs;
new_stack += STACKFRAME_SZ + TRACEREG_SZ;
childregs->u_regs[UREG_FP] = (unsigned long) new_stack;
p->thread.flags |= SPARC_FLAG_KTHREAD;
p->thread.current_ds = KERNEL_DS;
memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);
childregs->u_regs[UREG_G6] = (unsigned long) ti;
} else {
p->thread.kregs = childregs;
childregs->u_regs[UREG_FP] = sp;
p->thread.flags &= ~SPARC_FLAG_KTHREAD;
p->thread.current_ds = USER_DS;
if (sp != regs->u_regs[UREG_FP]) {
struct sparc_stackf __user *childstack;
struct sparc_stackf __user *parentstack;
/*
* This is a clone() call with supplied user stack.
* Set some valid stack frames to give to the child.
*/
childstack = (struct sparc_stackf __user *)
(sp & ~0xfUL);
parentstack = (struct sparc_stackf __user *)
regs->u_regs[UREG_FP];
#if 0
printk("clone: parent stack:\n");
show_stackframe(parentstack);
#endif
childstack = clone_stackframe(childstack, parentstack);
if (!childstack)
return -EFAULT;
#if 0
printk("clone: child stack:\n");
show_stackframe(childstack);
#endif
childregs->u_regs[UREG_FP] = (unsigned long)childstack;
}
}
#ifdef CONFIG_SMP
/* FPU must be disabled on SMP. */
childregs->psr &= ~PSR_EF;
#endif
/* Set the return value for the child. */
childregs->u_regs[UREG_I0] = current->pid;
childregs->u_regs[UREG_I1] = 1;
/* Set the return value for the parent. */
regs->u_regs[UREG_I1] = 0;
if (clone_flags & CLONE_SETTLS)
childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
return 0;
}
/*
* fill in the fpu structure for a core dump.
*/
int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
{
if (used_math()) {
memset(fpregs, 0, sizeof(*fpregs));
fpregs->pr_q_entrysize = 8;
return 1;
}
#ifdef CONFIG_SMP
if (test_thread_flag(TIF_USEDFPU)) {
put_psr(get_psr() | PSR_EF);
fpsave(&current->thread.float_regs[0], &current->thread.fsr,
&current->thread.fpqueue[0], &current->thread.fpqdepth);
if (regs != NULL) {
regs->psr &= ~(PSR_EF);
clear_thread_flag(TIF_USEDFPU);
}
}
#else
if (current == last_task_used_math) {
put_psr(get_psr() | PSR_EF);
fpsave(&current->thread.float_regs[0], &current->thread.fsr,
&current->thread.fpqueue[0], &current->thread.fpqdepth);
if (regs != NULL) {
regs->psr &= ~(PSR_EF);
last_task_used_math = NULL;
}
}
#endif
memcpy(&fpregs->pr_fr.pr_regs[0],
&current->thread.float_regs[0],
(sizeof(unsigned long) * 32));
fpregs->pr_fsr = current->thread.fsr;
fpregs->pr_qcnt = current->thread.fpqdepth;
fpregs->pr_q_entrysize = 8;
fpregs->pr_en = 1;
if(fpregs->pr_qcnt != 0) {
memcpy(&fpregs->pr_q[0],
&current->thread.fpqueue[0],
sizeof(struct fpq) * fpregs->pr_qcnt);
}
/* Zero out the rest. */
memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
return 1;
}
/*
* sparc_execve() executes a new program after the asm stub has set
* things up for us. This should basically do what I want it to.
*/
asmlinkage int sparc_execve(struct pt_regs *regs)
{
int error, base = 0;
char *filename;
/* Check for indirect call. */
if(regs->u_regs[UREG_G1] == 0)
base = 1;
filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
error = PTR_ERR(filename);
if(IS_ERR(filename))
goto out;
error = do_execve(filename,
(char __user * __user *)regs->u_regs[base + UREG_I1],
(char __user * __user *)regs->u_regs[base + UREG_I2],
regs);
putname(filename);
out:
return error;
}
/*
* This is the mechanism for creating a new kernel thread.
*
* NOTE! Only a kernel-only process(ie the swapper or direct descendants
* who haven't done an "execve()") should use this: it will work within
* a system call from a "real" process, but the process memory space will
* not be freed until both the parent and the child have exited.
*/
pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
long retval;
__asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */
"mov %5, %%g3\n\t" /* and arg. */
"mov %1, %%g1\n\t"
"mov %2, %%o0\n\t" /* Clone flags. */
"mov 0, %%o1\n\t" /* usp arg == 0 */
"t 0x10\n\t" /* Linux/Sparc clone(). */
"cmp %%o1, 0\n\t"
"be 1f\n\t" /* The parent, just return. */
" nop\n\t" /* Delay slot. */
"jmpl %%g2, %%o7\n\t" /* Call the function. */
" mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
"mov %3, %%g1\n\t"
"t 0x10\n\t" /* Linux/Sparc exit(). */
/* Notreached by child. */
"1: mov %%o0, %0\n\t" :
"=r" (retval) :
"i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
"i" (__NR_exit), "r" (fn), "r" (arg) :
"g1", "g2", "g3", "o0", "o1", "memory", "cc");
return retval;
}
EXPORT_SYMBOL(kernel_thread);
unsigned long get_wchan(struct task_struct *task)
{
unsigned long pc, fp, bias = 0;
unsigned long task_base = (unsigned long) task;
unsigned long ret = 0;
struct reg_window32 *rw;
int count = 0;
if (!task || task == current ||
task->state == TASK_RUNNING)
goto out;
fp = task_thread_info(task)->ksp + bias;
do {
/* Bogus frame pointer? */
if (fp < (task_base + sizeof(struct thread_info)) ||
fp >= (task_base + (2 * PAGE_SIZE)))
break;
rw = (struct reg_window32 *) fp;
pc = rw->ins[7];
if (!in_sched_functions(pc)) {
ret = pc;
goto out;
}
fp = rw->ins[6] + bias;
} while (++count < 16);
out:
return ret;
}