diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-05 17:46:42 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-05 17:46:42 -0700 |
commit | e7fda6c4c3c1a7d6996dd75fd84670fa0b5d448f (patch) | |
tree | daa51c16462c318b890acf7f01fba5827275dd74 /arch/x86/kvm/x86.c | |
parent | 08d69a25714429850cf9ef71f22d8cdc9189d93f (diff) | |
parent | 953dec21aed4038464fec02f96a2f1b8701a5bce (diff) | |
download | linux-e7fda6c4c3c1a7d6996dd75fd84670fa0b5d448f.tar.gz linux-e7fda6c4c3c1a7d6996dd75fd84670fa0b5d448f.tar.bz2 linux-e7fda6c4c3c1a7d6996dd75fd84670fa0b5d448f.zip |
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer and time updates from Thomas Gleixner:
"A rather large update of timers, timekeeping & co
- Core timekeeping code is year-2038 safe now for 32bit machines.
Now we just need to fix all in kernel users and the gazillion of
user space interfaces which rely on timespec/timeval :)
- Better cache layout for the timekeeping internal data structures.
- Proper nanosecond based interfaces for in kernel users.
- Tree wide cleanup of code which wants nanoseconds but does hoops
and loops to convert back and forth from timespecs. Some of it
definitely belongs into the ugly code museum.
- Consolidation of the timekeeping interface zoo.
- A fast NMI safe accessor to clock monotonic for tracing. This is a
long standing request to support correlated user/kernel space
traces. With proper NTP frequency correction it's also suitable
for correlation of traces accross separate machines.
- Checkpoint/restart support for timerfd.
- A few NOHZ[_FULL] improvements in the [hr]timer code.
- Code move from kernel to kernel/time of all time* related code.
- New clocksource/event drivers from the ARM universe. I'm really
impressed that despite an architected timer in the newer chips SoC
manufacturers insist on inventing new and differently broken SoC
specific timers.
[ Ed. "Impressed"? I don't think that word means what you think it means ]
- Another round of code move from arch to drivers. Looks like most
of the legacy mess in ARM regarding timers is sorted out except for
a few obnoxious strongholds.
- The usual updates and fixlets all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits)
timekeeping: Fixup typo in update_vsyscall_old definition
clocksource: document some basic timekeeping concepts
timekeeping: Use cached ntp_tick_length when accumulating error
timekeeping: Rework frequency adjustments to work better w/ nohz
timekeeping: Minor fixup for timespec64->timespec assignment
ftrace: Provide trace clocks monotonic
timekeeping: Provide fast and NMI safe access to CLOCK_MONOTONIC
seqcount: Add raw_write_seqcount_latch()
seqcount: Provide raw_read_seqcount()
timekeeping: Use tk_read_base as argument for timekeeping_get_ns()
timekeeping: Create struct tk_read_base and use it in struct timekeeper
timekeeping: Restructure the timekeeper some more
clocksource: Get rid of cycle_last
clocksource: Move cycle_last validation to core code
clocksource: Make delta calculation a function
wireless: ath9k: Get rid of timespec conversions
drm: vmwgfx: Use nsec based interfaces
drm: i915: Use nsec based interfaces
timekeeping: Provide ktime_get_raw()
hangcheck-timer: Use ktime_get_ns()
...
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r-- | arch/x86/kvm/x86.c | 62 |
1 files changed, 21 insertions, 41 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b86d329b953a..ca3d760dd581 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1020,9 +1020,8 @@ struct pvclock_gtod_data { u32 shift; } clock; - /* open coded 'struct timespec' */ - u64 monotonic_time_snsec; - time_t monotonic_time_sec; + u64 boot_ns; + u64 nsec_base; }; static struct pvclock_gtod_data pvclock_gtod_data; @@ -1030,27 +1029,21 @@ static struct pvclock_gtod_data pvclock_gtod_data; static void update_pvclock_gtod(struct timekeeper *tk) { struct pvclock_gtod_data *vdata = &pvclock_gtod_data; + u64 boot_ns; + + boot_ns = ktime_to_ns(ktime_add(tk->tkr.base_mono, tk->offs_boot)); write_seqcount_begin(&vdata->seq); /* copy pvclock gtod data */ - vdata->clock.vclock_mode = tk->clock->archdata.vclock_mode; - vdata->clock.cycle_last = tk->clock->cycle_last; - vdata->clock.mask = tk->clock->mask; - vdata->clock.mult = tk->mult; - vdata->clock.shift = tk->shift; - - vdata->monotonic_time_sec = tk->xtime_sec - + tk->wall_to_monotonic.tv_sec; - vdata->monotonic_time_snsec = tk->xtime_nsec - + (tk->wall_to_monotonic.tv_nsec - << tk->shift); - while (vdata->monotonic_time_snsec >= - (((u64)NSEC_PER_SEC) << tk->shift)) { - vdata->monotonic_time_snsec -= - ((u64)NSEC_PER_SEC) << tk->shift; - vdata->monotonic_time_sec++; - } + vdata->clock.vclock_mode = tk->tkr.clock->archdata.vclock_mode; + vdata->clock.cycle_last = tk->tkr.cycle_last; + vdata->clock.mask = tk->tkr.mask; + vdata->clock.mult = tk->tkr.mult; + vdata->clock.shift = tk->tkr.shift; + + vdata->boot_ns = boot_ns; + vdata->nsec_base = tk->tkr.xtime_nsec; write_seqcount_end(&vdata->seq); } @@ -1145,11 +1138,7 @@ static void kvm_get_time_scale(uint32_t scaled_khz, uint32_t base_khz, static inline u64 get_kernel_ns(void) { - struct timespec ts; - - ktime_get_ts(&ts); - monotonic_to_bootbased(&ts); - return timespec_to_ns(&ts); + return ktime_get_boot_ns(); } #ifdef CONFIG_X86_64 @@ -1414,23 +1403,22 @@ static inline u64 vgettsc(cycle_t *cycle_now) return v * gtod->clock.mult; } -static int do_monotonic(struct timespec *ts, cycle_t *cycle_now) +static int do_monotonic_boot(s64 *t, cycle_t *cycle_now) { + struct pvclock_gtod_data *gtod = &pvclock_gtod_data; unsigned long seq; - u64 ns; int mode; - struct pvclock_gtod_data *gtod = &pvclock_gtod_data; + u64 ns; - ts->tv_nsec = 0; do { seq = read_seqcount_begin(>od->seq); mode = gtod->clock.vclock_mode; - ts->tv_sec = gtod->monotonic_time_sec; - ns = gtod->monotonic_time_snsec; + ns = gtod->nsec_base; ns += vgettsc(cycle_now); ns >>= gtod->clock.shift; + ns += gtod->boot_ns; } while (unlikely(read_seqcount_retry(>od->seq, seq))); - timespec_add_ns(ts, ns); + *t = ns; return mode; } @@ -1438,19 +1426,11 @@ static int do_monotonic(struct timespec *ts, cycle_t *cycle_now) /* returns true if host is using tsc clocksource */ static bool kvm_get_time_and_clockread(s64 *kernel_ns, cycle_t *cycle_now) { - struct timespec ts; - /* checked again under seqlock below */ if (pvclock_gtod_data.clock.vclock_mode != VCLOCK_TSC) return false; - if (do_monotonic(&ts, cycle_now) != VCLOCK_TSC) - return false; - - monotonic_to_bootbased(&ts); - *kernel_ns = timespec_to_ns(&ts); - - return true; + return do_monotonic_boot(kernel_ns, cycle_now) == VCLOCK_TSC; } #endif |