projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| d2312e33 SS |
2 | /* |
| 3 | * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE | |
| 4 | * Copyright 2003 Andi Kleen, SuSE Labs. | |
| 5 | * | |
| 6 | * Modified for x86 32 bit architecture by | |
| 7 | * Stefani Seibold <stefani@seibold.net> | |
| 7c03156f | 8 | * sponsored by Rohde & Schwarz GmbH & Co. KG Munich/Germany |
| d2312e33 SS |
9 | * |
| 10 | * Thanks to hpa@transmeta.com for some useful hint. | |
| 11 | * Special thanks to Ingo Molnar for his early experience with | |
| 12 | * a different vsyscall implementation for Linux/IA32 and for the name. | |
| 13 | * | |
| 14 | */ | |
| 15 | ||
| 16 | #include <linux/timekeeper_internal.h> | |
| 17 | #include <asm/vgtod.h> | |
| 7c03156f | 18 | #include <asm/vvar.h> |
| d2312e33 | 19 | |
| bd902c53 AL |
20 | int vclocks_used __read_mostly; |
| 21 | ||
| d2312e33 SS |
22 | DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data); |
| 23 | ||
| 24 | void update_vsyscall_tz(void) | |
| 25 | { | |
| 7c03156f SS |
26 | vsyscall_gtod_data.tz_minuteswest = sys_tz.tz_minuteswest; |
| 27 | vsyscall_gtod_data.tz_dsttime = sys_tz.tz_dsttime; | |
| d2312e33 SS |
28 | } |
| 29 | ||
| 30 | void update_vsyscall(struct timekeeper *tk) | |
| 31 | { | |
| bd902c53 | 32 | int vclock_mode = tk->tkr_mono.clock->archdata.vclock_mode; |
| d2312e33 SS |
33 | struct vsyscall_gtod_data *vdata = &vsyscall_gtod_data; |
| 34 | ||
| bd902c53 AL |
35 | /* Mark the new vclock used. */ |
| 36 | BUILD_BUG_ON(VCLOCK_MAX >= 32); | |
| 37 | WRITE_ONCE(vclocks_used, READ_ONCE(vclocks_used) | (1 << vclock_mode)); | |
| 38 | ||
| 7c03156f | 39 | gtod_write_begin(vdata); |
| d2312e33 SS |
40 | |
| 41 | /* copy vsyscall data */ | |
| bd902c53 | 42 | vdata->vclock_mode = vclock_mode; |
| 876e7881 PZ |
43 | vdata->cycle_last = tk->tkr_mono.cycle_last; |
| 44 | vdata->mask = tk->tkr_mono.mask; | |
| 45 | vdata->mult = tk->tkr_mono.mult; | |
| 46 | vdata->shift = tk->tkr_mono.shift; | |
| d2312e33 SS |
47 | |
| 48 | vdata->wall_time_sec = tk->xtime_sec; | |
| 876e7881 | 49 | vdata->wall_time_snsec = tk->tkr_mono.xtime_nsec; |
| d2312e33 SS |
50 | |
| 51 | vdata->monotonic_time_sec = tk->xtime_sec | |
| 52 | + tk->wall_to_monotonic.tv_sec; | |
| 876e7881 | 53 | vdata->monotonic_time_snsec = tk->tkr_mono.xtime_nsec |
| 28b92e09 | 54 | + ((u64)tk->wall_to_monotonic.tv_nsec |
| 876e7881 | 55 | << tk->tkr_mono.shift); |
| d2312e33 | 56 | while (vdata->monotonic_time_snsec >= |
| 876e7881 | 57 | (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) { |
| d2312e33 | 58 | vdata->monotonic_time_snsec -= |
| 876e7881 | 59 | ((u64)NSEC_PER_SEC) << tk->tkr_mono.shift; |
| d2312e33 SS |
60 | vdata->monotonic_time_sec++; |
| 61 | } | |
| 62 | ||
| 7c03156f | 63 | vdata->wall_time_coarse_sec = tk->xtime_sec; |
| 876e7881 PZ |
64 | vdata->wall_time_coarse_nsec = (long)(tk->tkr_mono.xtime_nsec >> |
| 65 | tk->tkr_mono.shift); | |
| d2312e33 | 66 | |
| 7c03156f SS |
67 | vdata->monotonic_time_coarse_sec = |
| 68 | vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec; | |
| 69 | vdata->monotonic_time_coarse_nsec = | |
| 70 | vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec; | |
| d2312e33 | 71 | |
| 7c03156f SS |
72 | while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) { |
| 73 | vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC; | |
| 74 | vdata->monotonic_time_coarse_sec++; | |
| 75 | } | |
| 76 | ||
| 77 | gtod_write_end(vdata); | |
| d2312e33 | 78 | } |