diff options
Diffstat (limited to 'arch/s390/kernel/switch_cpu64.S')
| -rw-r--r-- | arch/s390/kernel/switch_cpu64.S | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/arch/s390/kernel/switch_cpu64.S b/arch/s390/kernel/switch_cpu64.S new file mode 100644 index 0000000..d94aacc --- /dev/null +++ b/arch/s390/kernel/switch_cpu64.S @@ -0,0 +1,51 @@ +/* + * 64-bit switch cpu code + * + * Copyright IBM Corp. 2009 + * + */ + +#include <asm/asm-offsets.h> +#include <asm/ptrace.h> + +# smp_switch_to_cpu switches to destination cpu and executes the passed function +# Parameter: %r2 - function to call +# %r3 - function parameter +# %r4 - stack poiner +# %r5 - current cpu +# %r6 - destination cpu + + .section .text + .align 4 + .globl smp_switch_to_cpu +smp_switch_to_cpu: + stmg %r6,%r15,__SF_GPRS(%r15) + lgr %r1,%r15 + aghi %r15,-STACK_FRAME_OVERHEAD + stg %r1,__SF_BACKCHAIN(%r15) + larl %r1,.gprregs + stmg %r0,%r15,0(%r1) +1: sigp %r0,%r6,__SIGP_RESTART /* start destination CPU */ + brc 2,1b /* busy, try again */ +2: sigp %r0,%r5,__SIGP_STOP /* stop current CPU */ + brc 2,2b /* busy, try again */ +3: j 3b + + .globl smp_restart_cpu +smp_restart_cpu: + larl %r1,.gprregs + lmg %r0,%r15,0(%r1) +1: sigp %r0,%r5,__SIGP_SENSE /* Wait for calling CPU */ + brc 10,1b /* busy, accepted (status 0), running */ + tmll %r0,0x40 /* Test if calling CPU is stopped */ + jz 1b + ltgr %r4,%r4 /* New stack ? */ + jz 1f + lgr %r15,%r4 +1: basr %r14,%r2 + + .section .data,"aw",@progbits +.gprregs: + .rept 16 + .quad 0 + .endr |