diff options
Diffstat (limited to 'arch/x86/entry/vsyscall/vsyscall_gtod.c')
| -rw-r--r-- | arch/x86/entry/vsyscall/vsyscall_gtod.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/x86/entry/vsyscall/vsyscall_gtod.c b/arch/x86/entry/vsyscall/vsyscall_gtod.c index 51e330416995..0fb3a104ac62 100644 --- a/arch/x86/entry/vsyscall/vsyscall_gtod.c +++ b/arch/x86/entry/vsyscall/vsyscall_gtod.c @@ -16,6 +16,8 @@ #include <asm/vgtod.h> #include <asm/vvar.h> +int vclocks_used __read_mostly; + DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data); void update_vsyscall_tz(void) @@ -26,12 +28,17 @@ void update_vsyscall_tz(void) void update_vsyscall(struct timekeeper *tk) { + int vclock_mode = tk->tkr_mono.clock->archdata.vclock_mode; struct vsyscall_gtod_data *vdata = &vsyscall_gtod_data; + /* Mark the new vclock used. */ + BUILD_BUG_ON(VCLOCK_MAX >= 32); + WRITE_ONCE(vclocks_used, READ_ONCE(vclocks_used) | (1 << vclock_mode)); + gtod_write_begin(vdata); /* copy vsyscall data */ - vdata->vclock_mode = tk->tkr_mono.clock->archdata.vclock_mode; + vdata->vclock_mode = vclock_mode; vdata->cycle_last = tk->tkr_mono.cycle_last; vdata->mask = tk->tkr_mono.mask; vdata->mult = tk->tkr_mono.mult; |