Commit d0164ee2 authored by Hendrik Brueckner's avatar Hendrik Brueckner Committed by Martin Schwidefsky
Browse files

s390/kernel: remove save_fpu_regs() parameter and use __LC_CURRENT instead 



All calls to save_fpu_regs() specify the fpu structure of the current task
pointer as parameter.  The task pointer of the current task can also be
retrieved from the CPU lowcore directly.  Remove the parameter definition,
load the __LC_CURRENT task pointer from the CPU lowcore, and rebase the FPU
structure onto the task structure.  Apply the same approach for the
load_fpu_regs() function.

Reviewed-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 2a01bd1b

arch/s390/include/asm/fpu-internal.h

+1 −1
Original line number Diff line number Diff line
@@ -28,7 +28,7 @@ struct fpu { 
	};

};



void save_fpu_regs(struct fpu *fpu);

void save_fpu_regs(void);



#define is_vx_fpu(fpu) (!!((fpu)->flags & FPU_USE_VX))

#define is_vx_task(tsk) (!!((tsk)->thread.fpu.flags & FPU_USE_VX))

arch/s390/include/asm/switch_to.h

+1 −1
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ static inline void restore_access_regs(unsigned int *acrs) 


#define switch_to(prev,next,last) do {					\

	if (prev->mm) {							\

		save_fpu_regs(&prev->thread.fpu);			\

		save_fpu_regs();					\

		save_access_regs(&prev->thread.acrs[0]);		\

		save_ri_cb(prev->thread.ri_cb);				\

	}								\

arch/s390/kernel/asm-offsets.c

+3 −5
Original line number Diff line number Diff line
@@ -28,16 +28,14 @@ int main(void) 
	DEFINE(__TASK_pid, offsetof(struct task_struct, pid));

	BLANK();

	DEFINE(__THREAD_ksp, offsetof(struct thread_struct, ksp));

	DEFINE(__THREAD_fpu, offsetof(struct task_struct, thread.fpu));

	DEFINE(__THREAD_FPU_fpc, offsetof(struct thread_struct, fpu.fpc));

	DEFINE(__THREAD_FPU_flags, offsetof(struct thread_struct, fpu.flags));

	DEFINE(__THREAD_FPU_regs, offsetof(struct thread_struct, fpu.regs));

	DEFINE(__THREAD_per_cause, offsetof(struct thread_struct, per_event.cause));

	DEFINE(__THREAD_per_address, offsetof(struct thread_struct, per_event.address));

	DEFINE(__THREAD_per_paid, offsetof(struct thread_struct, per_event.paid));

	DEFINE(__THREAD_trap_tdb, offsetof(struct thread_struct, trap_tdb));

	BLANK();

	DEFINE(__FPU_fpc, offsetof(struct fpu, fpc));

	DEFINE(__FPU_flags, offsetof(struct fpu, flags));

	DEFINE(__FPU_regs, offsetof(struct fpu, regs));

	BLANK();

	DEFINE(__TI_task, offsetof(struct thread_info, task));

	DEFINE(__TI_flags, offsetof(struct thread_info, flags));

	DEFINE(__TI_sysc_table, offsetof(struct thread_info, sys_call_table));

arch/s390/kernel/compat_signal.c

+3 −3
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from) 
static void store_sigregs(void)

{

	save_access_regs(current->thread.acrs);

	save_fpu_regs(&current->thread.fpu);

	save_fpu_regs();

}



/* Load registers after signal return */
@@ -286,7 +286,7 @@ COMPAT_SYSCALL_DEFINE0(sigreturn) 
	if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE32))

		goto badframe;

	set_current_blocked(&set);

	save_fpu_regs(&current->thread.fpu);

	save_fpu_regs();

	if (restore_sigregs32(regs, &frame->sregs))

		goto badframe;

	if (restore_sigregs_ext32(regs, &frame->sregs_ext))
@@ -309,7 +309,7 @@ COMPAT_SYSCALL_DEFINE0(rt_sigreturn) 
	set_current_blocked(&set);

	if (compat_restore_altstack(&frame->uc.uc_stack))

		goto badframe;

	save_fpu_regs(&current->thread.fpu);

	save_fpu_regs();

	if (restore_sigregs32(regs, &frame->uc.uc_mcontext))

		goto badframe;

	if (restore_sigregs_ext32(regs, &frame->uc.uc_mcontext_ext))

arch/s390/kernel/entry.S

+18 −18
Original line number Diff line number Diff line
@@ -183,7 +183,6 @@ ENTRY(sie64a) 
	xc	__SF_EMPTY+16(16,%r15),__SF_EMPTY+16(%r15) # host id & reason

	tm	__LC_CPU_FLAGS+7,_CIF_FPU	# load guest fp/vx registers ?

	jno	.Lsie_load_guest_gprs

	lg	%r12,__LC_THREAD_INFO		# load fp/vx regs save area

	brasl	%r14,load_fpu_regs		# load guest fp/vx regs

.Lsie_load_guest_gprs:

	lmg	%r0,%r13,0(%r3)			# load guest gprs 0-13
@@ -752,14 +751,16 @@ ENTRY(psw_idle) 
 * of the register contents at system call or io return.

 */

ENTRY(save_fpu_regs)

	lg	%r2,__LC_CURRENT

	aghi	%r2,__TASK_thread

	tm	__LC_CPU_FLAGS+7,_CIF_FPU

	bor	%r14

	stfpc	__FPU_fpc(%r2)

	stfpc	__THREAD_FPU_fpc(%r2)

.Lsave_fpu_regs_fpc_end:

	lg	%r3,__FPU_regs(%r2)

	lg	%r3,__THREAD_FPU_regs(%r2)

	ltgr	%r3,%r3

	jz	.Lsave_fpu_regs_done	  # no save area -> set CIF_FPU

	tm	__FPU_flags+3(%r2),FPU_USE_VX

	tm	__THREAD_FPU_flags+3(%r2),FPU_USE_VX

	jz	.Lsave_fpu_regs_fp	  # no -> store FP regs

.Lsave_fpu_regs_vx_low:

	VSTM	%v0,%v15,0,%r3		  # vstm 0,15,0(3)
@@ -794,20 +795,19 @@ ENTRY(save_fpu_regs) 
 * FP/VX state, the vector-enablement control, CR0.46, is either set or cleared.

 *

 * There are special calling conventions to fit into sysc and io return work:

 *	%r12:	__LC_THREAD_INFO

 *	%r15:	<kernel stack>

 * The function requires:

 *	%r4 and __SF_EMPTY+32(%r15)

 */

load_fpu_regs:

	lg	%r4,__LC_CURRENT

	aghi	%r4,__TASK_thread

	tm	__LC_CPU_FLAGS+7,_CIF_FPU

	bnor	%r14

	lg	%r4,__TI_task(%r12)

	la	%r4,__THREAD_fpu(%r4)

	lfpc	__FPU_fpc(%r4)

	lfpc	__THREAD_FPU_fpc(%r4)

	stctg	%c0,%c0,__SF_EMPTY+32(%r15)	# store CR0

	tm	__FPU_flags+3(%r4),FPU_USE_VX	# VX-enabled task ?

	lg	%r4,__FPU_regs(%r4)		# %r4 <- reg save area

	tm	__THREAD_FPU_flags+3(%r4),FPU_USE_VX	# VX-enabled task ?

	lg	%r4,__THREAD_FPU_regs(%r4)	# %r4 <- reg save area

	jz	.Lload_fpu_regs_fp_ctl		# -> no VX, load FP regs

.Lload_fpu_regs_vx_ctl:

	tm	__SF_EMPTY+32+5(%r15),2		# test VX control
@@ -1190,13 +1190,14 @@ cleanup_critical: 
	jhe	2f

	clg	%r9,BASED(.Lcleanup_save_fpu_fpc_end)

	jhe	1f

	lg	%r2,__LC_CURRENT

0:	# Store floating-point controls

	stfpc	__FPU_fpc(%r2)

	stfpc	__THREAD_FPU_fpc(%r2)

1:	# Load register save area and check if VX is active

	lg	%r3,__FPU_regs(%r2)

	lg	%r3,__THREAD_FPU_regs(%r2)

	ltgr	%r3,%r3

	jz	5f			  # no save area -> set CIF_FPU

	tm	__FPU_flags+3(%r2),FPU_USE_VX

	tm	__THREAD_FPU_flags+3(%r2),FPU_USE_VX

	jz	4f			  # no VX -> store FP regs

2:	# Store vector registers (V0-V15)

	VSTM	%v0,%v15,0,%r3		  # vstm 0,15,0(3)
@@ -1250,11 +1251,10 @@ cleanup_critical: 
	jhe	5f

	clg	%r9,BASED(.Lcleanup_load_fpu_regs_vx_ctl)

	jhe	6f

	lg	%r4,__TI_task(%r12)

	la	%r4,__THREAD_fpu(%r4)

	lfpc	__FPU_fpc(%r4)

	tm	__FPU_flags+3(%r4),FPU_USE_VX	# VX-enabled task ?

	lg	%r4,__FPU_regs(%r4)		# %r4 <- reg save area

	lg	%r4,__LC_CURRENT

	lfpc	__THREAD_FPU_fpc(%r4)

	tm	__THREAD_FPU_flags+3(%r4),FPU_USE_VX	# VX-enabled task ?

	lg	%r4,__THREAD_FPU_regs(%r4)	# %r4 <- reg save area

	jz	3f				# -> no VX, load FP regs

6:	# Set VX-enablement control

	stctg	%c0,%c0,__SF_EMPTY+32(%r15)	# store CR0

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