git://bbs.cooldavid.org / net-next-2.6.git / blame
| Commit | Line | Data |
|---|---|---|
| b020632e MS |
1 | /* |
| 2 | * Userland implementation of clock_gettime() for 64 bits processes in a | |
| 3 | * s390 kernel for use in the vDSO | |
| 4 | * | |
| 5 | * Copyright IBM Corp. 2008 | |
| 6 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or modify | |
| 9 | * it under the terms of the GNU General Public License (version 2 only) | |
| 10 | * as published by the Free Software Foundation. | |
| 11 | */ | |
| 12 | #include <asm/vdso.h> | |
| 13 | #include <asm/asm-offsets.h> | |
| 14 | #include <asm/unistd.h> | |
| 15 | ||
| 16 | .text | |
| 17 | .align 4 | |
| 18 | .globl __kernel_clock_gettime | |
| 19 | .type __kernel_clock_gettime,@function | |
| 20 | __kernel_clock_gettime: | |
| 21 | .cfi_startproc | |
| 22 | larl %r5,_vdso_data | |
| b3423982 | 23 | cghi %r2,__CLOCK_REALTIME |
| b020632e | 24 | je 4f |
| c742b31c MS |
25 | cghi %r2,-2 /* CLOCK_THREAD_CPUTIME_ID for this thread */ |
| 26 | je 9f | |
| b3423982 | 27 | cghi %r2,__CLOCK_MONOTONIC |
| c742b31c | 28 | jne 12f |
| b020632e MS |
29 | |
| 30 | /* CLOCK_MONOTONIC */ | |
| 31 | ltgr %r3,%r3 | |
| 32 | jz 3f /* tp == NULL */ | |
| 33 | 0: lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */ | |
| 34 | tmll %r4,0x0001 /* pending update ? loop */ | |
| 35 | jnz 0b | |
| 36 | stck 48(%r15) /* Store TOD clock */ | |
| 37 | lg %r1,48(%r15) | |
| 38 | sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ | |
| 157a1a27 | 39 | msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ |
| b020632e MS |
40 | srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ |
| 41 | alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ | |
| 42 | lg %r0,__VDSO_XTIME_SEC(%r5) | |
| 43 | alg %r1,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic */ | |
| 44 | alg %r0,__VDSO_WTOM_SEC(%r5) | |
| 45 | clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ | |
| 46 | jne 0b | |
| c742b31c | 47 | larl %r5,13f |
| b020632e MS |
48 | 1: clg %r1,0(%r5) |
| 49 | jl 2f | |
| 50 | slg %r1,0(%r5) | |
| 51 | aghi %r0,1 | |
| 52 | j 1b | |
| 53 | 2: stg %r0,0(%r3) /* store tp->tv_sec */ | |
| 54 | stg %r1,8(%r3) /* store tp->tv_nsec */ | |
| 55 | 3: lghi %r2,0 | |
| 56 | br %r14 | |
| 57 | ||
| 58 | /* CLOCK_REALTIME */ | |
| 59 | 4: ltr %r3,%r3 /* tp == NULL */ | |
| 60 | jz 8f | |
| 61 | 5: lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */ | |
| 62 | tmll %r4,0x0001 /* pending update ? loop */ | |
| 63 | jnz 5b | |
| 64 | stck 48(%r15) /* Store TOD clock */ | |
| 65 | lg %r1,48(%r15) | |
| 66 | sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ | |
| 157a1a27 | 67 | msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ |
| b020632e MS |
68 | srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ |
| 69 | alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ | |
| 70 | lg %r0,__VDSO_XTIME_SEC(%r5) | |
| 71 | clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ | |
| 72 | jne 5b | |
| c742b31c | 73 | larl %r5,13f |
| b020632e MS |
74 | 6: clg %r1,0(%r5) |
| 75 | jl 7f | |
| 76 | slg %r1,0(%r5) | |
| 77 | aghi %r0,1 | |
| 78 | j 6b | |
| 79 | 7: stg %r0,0(%r3) /* store tp->tv_sec */ | |
| 80 | stg %r1,8(%r3) /* store tp->tv_nsec */ | |
| 81 | 8: lghi %r2,0 | |
| 82 | br %r14 | |
| 83 | ||
| c742b31c MS |
84 | /* CLOCK_THREAD_CPUTIME_ID for this thread */ |
| 85 | 9: icm %r0,15,__VDSO_ECTG_OK(%r5) | |
| 86 | jz 12f | |
| 87 | ear %r2,%a4 | |
| 88 | llilh %r4,0x0100 | |
| 89 | sar %a4,%r4 | |
| 90 | lghi %r4,0 | |
| 1277580f | 91 | epsw %r5,0 |
| c742b31c MS |
92 | sacf 512 /* Magic ectg instruction */ |
| 93 | .insn ssf,0xc80100000000,__VDSO_ECTG_BASE(4),__VDSO_ECTG_USER(4),4 | |
| 1277580f MS |
94 | tml %r5,0x4000 |
| 95 | jo 11f | |
| 96 | tml %r5,0x8000 | |
| 97 | jno 10f | |
| 98 | sacf 256 | |
| 99 | j 11f | |
| 100 | 10: sacf 0 | |
| 101 | 11: sar %a4,%r2 | |
| c742b31c MS |
102 | algr %r1,%r0 /* r1 = cputime as TOD value */ |
| 103 | mghi %r1,1000 /* convert to nanoseconds */ | |
| 104 | srlg %r1,%r1,12 /* r1 = cputime in nanosec */ | |
| 105 | lgr %r4,%r1 | |
| 106 | larl %r5,13f | |
| 107 | srlg %r1,%r1,9 /* divide by 1000000000 */ | |
| 108 | mlg %r0,8(%r5) | |
| 109 | srlg %r0,%r0,11 /* r0 = tv_sec */ | |
| 110 | stg %r0,0(%r3) | |
| 111 | msg %r0,0(%r5) /* calculate tv_nsec */ | |
| 112 | slgr %r4,%r0 /* r4 = tv_nsec */ | |
| 113 | stg %r4,8(%r3) | |
| 114 | lghi %r2,0 | |
| 115 | br %r14 | |
| 116 | ||
| b020632e | 117 | /* Fallback to system call */ |
| c742b31c | 118 | 12: lghi %r1,__NR_clock_gettime |
| b020632e MS |
119 | svc 0 |
| 120 | br %r14 | |
| 121 | ||
| c742b31c MS |
122 | 13: .quad 1000000000 |
| 123 | 14: .quad 19342813113834067 | |
| b020632e MS |
124 | .cfi_endproc |
| 125 | .size __kernel_clock_gettime,.-__kernel_clock_gettime |