diff options
| author | Hendrik Brueckner <brueckner@linux.vnet.ibm.com> | 2015-09-29 17:53:22 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-10-14 14:32:08 +0200 |
| commit | 0ac277790ec938087c9047bc7b1b4f30a65406cd (patch) | |
| tree | 40b6d35e57e82258dbf1c6cafe8469b8b16dc375 | |
| parent | s390/fpu: always enable the vector facility if it is available (diff) | |
| download | linux-0ac277790ec938087c9047bc7b1b4f30a65406cd.tar.xz linux-0ac277790ec938087c9047bc7b1b4f30a65406cd.zip | |
s390/fpu: add static FPU save area for init_task
Previously, the init task did not have an allocated FPU save area and
saving an FPU state was not possible. Now if the vector extension is
always enabled, provide a static FPU save area to save FPU states of
vector instructions that can be executed quite early.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| -rw-r--r-- | arch/s390/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/s390/kernel/entry.S | 4 | ||||
| -rw-r--r-- | arch/s390/kernel/process.c | 4 |
3 files changed, 6 insertions, 4 deletions
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 085fb0d3c54e..5900877bb19c 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -139,8 +139,10 @@ struct stack_frame { #define ARCH_MIN_TASKALIGN 8 +extern __vector128 init_task_fpu_regs[__NUM_VXRS]; #define INIT_THREAD { \ .ksp = sizeof(init_stack) + (unsigned long) &init_stack, \ + .fpu.regs = (void *)&init_task_fpu_regs, \ } /* diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index b78babf9a417..3f23185c9173 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -762,8 +762,6 @@ ENTRY(save_fpu_regs) stfpc __THREAD_FPU_fpc(%r2) .Lsave_fpu_regs_fpc_end: lg %r3,__THREAD_FPU_regs(%r2) - ltgr %r3,%r3 - jz .Lsave_fpu_regs_done # no save area -> set CIF_FPU tm __LC_MACHINE_FLAGS+5,4 # MACHINE_HAS_VX jz .Lsave_fpu_regs_fp # no -> store FP regs .Lsave_fpu_regs_vx_low: @@ -1193,8 +1191,6 @@ cleanup_critical: stfpc __THREAD_FPU_fpc(%r2) 1: # Load register save area and check if VX is active lg %r3,__THREAD_FPU_regs(%r2) - ltgr %r3,%r3 - jz 5f # no save area -> set CIF_FPU tm __LC_MACHINE_FLAGS+5,4 # MACHINE_HAS_VX jz 4f # no VX -> store FP regs 2: # Store vector registers (V0-V15) diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index b63787156a19..cd5568608744 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 |