diff options
author | Alexander Graf <agraf@suse.de> | 2009-11-02 12:02:31 +0000 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2009-11-05 16:51:05 +1100 |
commit | 544c6761bb05a1dd19a39cb9bed096273f9bdb36 (patch) | |
tree | 66fde2d24a61c3be4712ac2701263aca04f26ebb /arch | |
parent | c8240bd6f0b4b1b21ffd36dd44114d05c7afe0c0 (diff) | |
download | op-kernel-dev-544c6761bb05a1dd19a39cb9bed096273f9bdb36.zip op-kernel-dev-544c6761bb05a1dd19a39cb9bed096273f9bdb36.tar.gz |
Use hrtimers for the decrementer
Following S390's good example we should use hrtimers for the decrementer too!
This patch converts the timer from the old mechanism to hrtimers.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/powerpc/include/asm/kvm_host.h | 6 | ||||
-rw-r--r-- | arch/powerpc/kvm/emulate.c | 18 | ||||
-rw-r--r-- | arch/powerpc/kvm/powerpc.c | 20 |
3 files changed, 33 insertions, 11 deletions
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 2cff5fe..1201f62 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -21,7 +21,8 @@ #define __POWERPC_KVM_HOST_H__ #include <linux/mutex.h> -#include <linux/timer.h> +#include <linux/hrtimer.h> +#include <linux/interrupt.h> #include <linux/types.h> #include <linux/kvm_types.h> #include <asm/kvm_asm.h> @@ -250,7 +251,8 @@ struct kvm_vcpu_arch { u32 cpr0_cfgaddr; /* holds the last set cpr0_cfgaddr */ - struct timer_list dec_timer; + struct hrtimer dec_timer; + struct tasklet_struct tasklet; u64 dec_jiffies; unsigned long pending_exceptions; diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index 1ec5e07..4a9ac66 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -18,7 +18,7 @@ */ #include <linux/jiffies.h> -#include <linux/timer.h> +#include <linux/hrtimer.h> #include <linux/types.h> #include <linux/string.h> #include <linux/kvm_host.h> @@ -79,12 +79,13 @@ static int kvmppc_dec_enabled(struct kvm_vcpu *vcpu) void kvmppc_emulate_dec(struct kvm_vcpu *vcpu) { - unsigned long nr_jiffies; + unsigned long dec_nsec; + pr_debug("mtDEC: %x\n", vcpu->arch.dec); #ifdef CONFIG_PPC64 /* POWER4+ triggers a dec interrupt if the value is < 0 */ if (vcpu->arch.dec & 0x80000000) { - del_timer(&vcpu->arch.dec_timer); + hrtimer_try_to_cancel(&vcpu->arch.dec_timer); kvmppc_core_queue_dec(vcpu); return; } @@ -94,12 +95,15 @@ void kvmppc_emulate_dec(struct kvm_vcpu *vcpu) * that's how we convert the guest DEC value to the number of * host ticks. */ + hrtimer_try_to_cancel(&vcpu->arch.dec_timer); + dec_nsec = vcpu->arch.dec; + dec_nsec *= 1000; + dec_nsec /= tb_ticks_per_usec; + hrtimer_start(&vcpu->arch.dec_timer, ktime_set(0, dec_nsec), + HRTIMER_MODE_REL); vcpu->arch.dec_jiffies = get_tb(); - nr_jiffies = vcpu->arch.dec / tb_ticks_per_jiffy; - mod_timer(&vcpu->arch.dec_timer, - get_jiffies_64() + nr_jiffies); } else { - del_timer(&vcpu->arch.dec_timer); + hrtimer_try_to_cancel(&vcpu->arch.dec_timer); } } diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index a06ecc3..692c370 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -23,6 +23,7 @@ #include <linux/kvm_host.h> #include <linux/module.h> #include <linux/vmalloc.h> +#include <linux/hrtimer.h> #include <linux/fs.h> #include <asm/cputable.h> #include <asm/uaccess.h> @@ -208,10 +209,25 @@ static void kvmppc_decrementer_func(unsigned long data) } } +/* + * low level hrtimer wake routine. Because this runs in hardirq context + * we schedule a tasklet to do the real work. + */ +enum hrtimer_restart kvmppc_decrementer_wakeup(struct hrtimer *timer) +{ + struct kvm_vcpu *vcpu; + + vcpu = container_of(timer, struct kvm_vcpu, arch.dec_timer); + tasklet_schedule(&vcpu->arch.tasklet); + + return HRTIMER_NORESTART; +} + int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { - setup_timer(&vcpu->arch.dec_timer, kvmppc_decrementer_func, - (unsigned long)vcpu); + hrtimer_init(&vcpu->arch.dec_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS); + tasklet_init(&vcpu->arch.tasklet, kvmppc_decrementer_func, (ulong)vcpu); + vcpu->arch.dec_timer.function = kvmppc_decrementer_wakeup; return 0; } |