diff options
author | Mark Brown <broonie@linaro.org> | 2014-03-14 12:32:15 +0000 |
---|---|---|
committer | Mark Brown <broonie@linaro.org> | 2014-03-14 12:32:15 +0000 |
commit | f58d5ed0c4c47aa8dbcc4f7a58e4c52752ce6511 (patch) | |
tree | fb4b04d21b4d8654b0e7a615f2b3bc445b48d08c /arch/x86/kvm/i8254.c | |
parent | 8bb495e3f02401ee6f76d1b1d77f3ac9f079e376 (diff) | |
parent | eb192460ccd50e73475b6092a8953ef7945921c8 (diff) |
Merge branch 'linux-linaro-lsk-v3.10/be/32/core-20140413' of git://git.linaro.org/people/victor.kamensky/linux-linaro-tracking-be into lsk-v3.10-bev3.10/topic/old-arm64-bev3.10/topic/be
Diffstat (limited to 'arch/x86/kvm/i8254.c')
-rw-r--r-- | arch/x86/kvm/i8254.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index 412a5aa0ef94..518d86471b76 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -37,6 +37,7 @@ #include "irq.h" #include "i8254.h" +#include "x86.h" #ifndef CONFIG_X86_64 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y)) @@ -349,6 +350,23 @@ static void create_pit_timer(struct kvm *kvm, u32 val, int is_period) atomic_set(&ps->pending, 0); ps->irq_ack = 1; + /* + * Do not allow the guest to program periodic timers with small + * interval, since the hrtimers are not throttled by the host + * scheduler. + */ + if (ps->is_periodic) { + s64 min_period = min_timer_period_us * 1000LL; + + if (ps->period < min_period) { + pr_info_ratelimited( + "kvm: requested %lld ns " + "i8254 timer period limited to %lld ns\n", + ps->period, min_period); + ps->period = min_period; + } + } + hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval), HRTIMER_MODE_ABS); } |