Currently we can only get the cpu_stat of whole guest as one. This patch enhanced cpu_stat with more detail, has guest_system and guest_user cpu time statistics with a little overhead.
Signed-off-by: Sheng Yang <[email protected]> --- This draft patch based on KVM upstream to show the idea. I would split it into more kernel friendly version later. The overhead is, the cost of get_cpl() after each exit from guest. Comments are welcome! arch/x86/kvm/x86.c | 10 ++++++++++ fs/proc/stat.c | 22 ++++++++++++++++------ include/linux/kernel_stat.h | 2 ++ include/linux/kvm_host.h | 1 + include/linux/sched.h | 1 + kernel/sched.c | 6 ++++++ 6 files changed, 36 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 703f637..c8ea6e1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4290,6 +4290,14 @@ static void inject_pending_event(struct kvm_vcpu *vcpu) } } +static void kvm_update_guest_mode(struct kvm_vcpu *vcpu) +{ + int cpl = kvm_x86_ops->get_cpl(vcpu); + + if (cpl != 0) + current->flags |= PF_VCPU_USER; +} + static int vcpu_enter_guest(struct kvm_vcpu *vcpu) { int r; @@ -4377,6 +4385,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) trace_kvm_entry(vcpu->vcpu_id); kvm_x86_ops->run(vcpu); + kvm_update_guest_mode(vcpu); + /* * If the guest has used debug registers, at least dr7 * will be disabled while returning to the host. diff --git a/fs/proc/stat.c b/fs/proc/stat.c index b9b7aad..d07640a 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -27,7 +27,7 @@ static int show_stat(struct seq_file *p, void *v) int i, j; unsigned long jif; cputime64_t user, nice, system, idle, iowait, irq, softirq, steal; - cputime64_t guest, guest_nice; + cputime64_t guest, guest_nice, guest_user, guest_system; u64 sum = 0; u64 sum_softirq = 0; unsigned int per_softirq_sums[NR_SOFTIRQS] = {0}; @@ -36,7 +36,7 @@ static int show_stat(struct seq_file *p, void *v) user = nice = system = idle = iowait = irq = softirq = steal = cputime64_zero; - guest = guest_nice = cputime64_zero; + guest = guest_nice = guest_user = guest_system = cputime64_zero; getboottime(&boottime); jif = boottime.tv_sec; @@ -53,6 +53,10 @@ static int show_stat(struct seq_file *p, void *v) guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest); guest_nice = cputime64_add(guest_nice, kstat_cpu(i).cpustat.guest_nice); + guest_user = cputime64_add(guest_user, + kstat_cpu(i).cpustat.guest_user); + guest_system = cputime64_add(guest_system, + kstat_cpu(i).cpustat.guest_system); for_each_irq_nr(j) { sum += kstat_irqs_cpu(j, i); } @@ -68,7 +72,7 @@ static int show_stat(struct seq_file *p, void *v) sum += arch_irq_stat(); seq_printf(p, "cpu %llu %llu %llu %llu %llu %llu %llu %llu %llu " - "%llu\n", + "%llu %llu %llu\n", (unsigned long long)cputime64_to_clock_t(user), (unsigned long long)cputime64_to_clock_t(nice), (unsigned long long)cputime64_to_clock_t(system), @@ -78,7 +82,9 @@ static int show_stat(struct seq_file *p, void *v) (unsigned long long)cputime64_to_clock_t(softirq), (unsigned long long)cputime64_to_clock_t(steal), (unsigned long long)cputime64_to_clock_t(guest), - (unsigned long long)cputime64_to_clock_t(guest_nice)); + (unsigned long long)cputime64_to_clock_t(guest_nice), + (unsigned long long)cputime64_to_clock_t(guest_user), + (unsigned long long)cputime64_to_clock_t(guest_system)); for_each_online_cpu(i) { /* Copy values here to work around gcc-2.95.3, gcc-2.96 */ @@ -93,9 +99,11 @@ static int show_stat(struct seq_file *p, void *v) steal = kstat_cpu(i).cpustat.steal; guest = kstat_cpu(i).cpustat.guest; guest_nice = kstat_cpu(i).cpustat.guest_nice; + guest_user = kstat_cpu(i).cpustat.guest_user; + guest_system = kstat_cpu(i).cpustat.guest_system; seq_printf(p, "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu %llu " - "%llu\n", + "%llu %llu %llu\n", i, (unsigned long long)cputime64_to_clock_t(user), (unsigned long long)cputime64_to_clock_t(nice), @@ -106,7 +114,9 @@ static int show_stat(struct seq_file *p, void *v) (unsigned long long)cputime64_to_clock_t(softirq), (unsigned long long)cputime64_to_clock_t(steal), (unsigned long long)cputime64_to_clock_t(guest), - (unsigned long long)cputime64_to_clock_t(guest_nice)); + (unsigned long long)cputime64_to_clock_t(guest_nice), + (unsigned long long)cputime64_to_clock_t(guest_user), + (unsigned long long)cputime64_to_clock_t(guest_system)); } seq_printf(p, "intr %llu", (unsigned long long)sum); diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h index c059044..e43b2f7 100644 --- a/include/linux/kernel_stat.h +++ b/include/linux/kernel_stat.h @@ -26,6 +26,8 @@ struct cpu_usage_stat { cputime64_t steal; cputime64_t guest; cputime64_t guest_nice; + cputime64_t guest_user; + cputime64_t guest_system; }; struct kernel_stat { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index a3fd0f9..497e795 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -496,6 +496,7 @@ static inline void kvm_guest_exit(void) { account_system_vtime(current); current->flags &= ~PF_VCPU; + current->flags &= ~PF_VCPU_USER; } static inline gpa_t gfn_to_gpa(gfn_t gfn) diff --git a/include/linux/sched.h b/include/linux/sched.h index 78efe7c..49bf81d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1759,6 +1759,7 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t * #define PF_EXITING 0x00000004 /* getting shut down */ #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ +#define PF_VCPU_USER 0x00000020 /* I'm a virtual CPU in usermode */ #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ diff --git a/kernel/sched.c b/kernel/sched.c index 3a8fb30..9cfc288 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -5092,6 +5092,12 @@ static void account_guest_time(struct task_struct *p, cputime_t cputime, } else { cpustat->user = cputime64_add(cpustat->user, tmp); cpustat->guest = cputime64_add(cpustat->guest, tmp); + if (p->flags & PF_VCPU_USER) + cpustat->guest_user = + cputime64_add(cpustat->guest_user, tmp); + else + cpustat->guest_system = + cputime64_add(cpustat->guest_system, tmp); } } -- 1.7.0.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
