diff options
Diffstat (limited to 'arch/s390/kernel/process.c')
| -rw-r--r-- | arch/s390/kernel/process.c | 37 |
1 files changed, 19 insertions, 18 deletions
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index f2dac9f0799d..688a3aad9c79 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -23,6 +23,7 @@ #include <linux/kprobes.h> #include <linux/random.h> #include <linux/module.h> +#include <linux/init_task.h> #include <asm/io.h> #include <asm/processor.h> #include <asm/vtimer.h> @@ -36,6 +37,9 @@ asmlinkage void ret_from_fork(void) asm ("ret_from_fork"); +/* FPU save area for the init task */ +__vector128 init_task_fpu_regs[__NUM_VXRS] __init_task_data; + /* * Return saved PC of a blocked thread. used in kernel/sched. * resume in entry.S does not create a new stack frame, it @@ -87,31 +91,29 @@ void arch_release_task_struct(struct task_struct *tsk) int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) { + size_t fpu_regs_size; + *dst = *src; - /* Set up a new floating-point register save area */ - dst->thread.fpu.fpc = 0; - dst->thread.fpu.flags = 0; /* Always start with VX disabled */ - dst->thread.fpu.fprs = kzalloc(sizeof(freg_t) * __NUM_FPRS, - GFP_KERNEL|__GFP_REPEAT); - if (!dst->thread.fpu.fprs) + /* + * If the vector extension is available, it is enabled for all tasks, + * and, thus, the FPU register save area must be allocated accordingly. + */ + fpu_regs_size = MACHINE_HAS_VX ? sizeof(__vector128) * __NUM_VXRS + : sizeof(freg_t) * __NUM_FPRS; + dst->thread.fpu.regs = kzalloc(fpu_regs_size, GFP_KERNEL|__GFP_REPEAT); + if (!dst->thread.fpu.regs) return -ENOMEM; /* * Save the floating-point or vector register state of the current - * task. The state is not saved for early kernel threads, for example, - * the init_task, which do not have an allocated save area. - * The CIF_FPU flag is set in any case to lazy clear or restore a saved - * state when switching to a different task or returning to user space. + * task and set the CIF_FPU flag to lazy restore the FPU register + * state when returning to user space. */ save_fpu_regs(); dst->thread.fpu.fpc = current->thread.fpu.fpc; - if (is_vx_task(current)) - convert_vx_to_fp(dst->thread.fpu.fprs, - current->thread.fpu.vxrs); - else - memcpy(dst->thread.fpu.fprs, current->thread.fpu.fprs, - sizeof(freg_t) * __NUM_FPRS); + memcpy(dst->thread.fpu.regs, current->thread.fpu.regs, fpu_regs_size); + return 0; } @@ -169,7 +171,6 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp, /* Don't copy runtime instrumentation info */ p->thread.ri_cb = NULL; - p->thread.ri_signum = 0; frame->childregs.psw.mask &= ~PSW_MASK_RI; /* Set a new TLS ? */ @@ -199,7 +200,7 @@ int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs) save_fpu_regs(); fpregs->fpc = current->thread.fpu.fpc; fpregs->pad = 0; - if (is_vx_task(current)) + if (MACHINE_HAS_VX) convert_vx_to_fp((freg_t *)&fpregs->fprs, current->thread.fpu.vxrs); else |