Add three log histogram stats to record the distribution of time spent
on successful polling, failed polling and VCPU wait.
halt_poll_success_hist: Distribution of spent time for a successful poll.
halt_poll_fail_hist: Distribution of spent time for a failed poll.
halt_wait_hist: Distribution of time a VCPU has spent on waiting.
Signed-off-by: Jing Zhang <jingzhangos@google.com>
Message-Id: <
20210802165633.
1866976-6-jingzhangos@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
if (do_sleep) {
vc->runner->stat.generic.halt_wait_ns +=
ktime_to_ns(cur) - ktime_to_ns(start_wait);
+ KVM_STATS_LOG_HIST_UPDATE(
+ vc->runner->stat.generic.halt_wait_hist,
+ ktime_to_ns(cur) - ktime_to_ns(start_wait));
/* Attribute failed poll time */
- if (vc->halt_poll_ns)
+ if (vc->halt_poll_ns) {
vc->runner->stat.generic.halt_poll_fail_ns +=
ktime_to_ns(start_wait) -
ktime_to_ns(start_poll);
+ KVM_STATS_LOG_HIST_UPDATE(
+ vc->runner->stat.generic.halt_poll_fail_hist,
+ ktime_to_ns(start_wait) -
+ ktime_to_ns(start_poll));
+ }
} else {
/* Attribute successful poll time */
- if (vc->halt_poll_ns)
+ if (vc->halt_poll_ns) {
vc->runner->stat.generic.halt_poll_success_ns +=
ktime_to_ns(cur) -
ktime_to_ns(start_poll);
+ KVM_STATS_LOG_HIST_UPDATE(
+ vc->runner->stat.generic.halt_poll_success_hist,
+ ktime_to_ns(cur) - ktime_to_ns(start_poll));
+ }
}
/* Adjust poll time */
STATS_DESC_COUNTER(VCPU_GENERIC, halt_wakeup), \
STATS_DESC_TIME_NSEC(VCPU_GENERIC, halt_poll_success_ns), \
STATS_DESC_TIME_NSEC(VCPU_GENERIC, halt_poll_fail_ns), \
- STATS_DESC_TIME_NSEC(VCPU_GENERIC, halt_wait_ns)
+ STATS_DESC_TIME_NSEC(VCPU_GENERIC, halt_wait_ns), \
+ STATS_DESC_LOGHIST_TIME_NSEC(VCPU_GENERIC, halt_poll_success_hist, \
+ HALT_POLL_HIST_COUNT), \
+ STATS_DESC_LOGHIST_TIME_NSEC(VCPU_GENERIC, halt_poll_fail_hist, \
+ HALT_POLL_HIST_COUNT), \
+ STATS_DESC_LOGHIST_TIME_NSEC(VCPU_GENERIC, halt_wait_hist, \
+ HALT_POLL_HIST_COUNT)
extern struct dentry *kvm_debugfs_dir;
};
#endif
+#define HALT_POLL_HIST_COUNT 32
+
struct kvm_vm_stat_generic {
u64 remote_tlb_flush;
};
u64 halt_poll_success_ns;
u64 halt_poll_fail_ns;
u64 halt_wait_ns;
+ u64 halt_poll_success_hist[HALT_POLL_HIST_COUNT];
+ u64 halt_poll_fail_hist[HALT_POLL_HIST_COUNT];
+ u64 halt_wait_hist[HALT_POLL_HIST_COUNT];
};
#define KVM_STATS_NAME_SIZE 48
++vcpu->stat.generic.halt_successful_poll;
if (!vcpu_valid_wakeup(vcpu))
++vcpu->stat.generic.halt_poll_invalid;
+
+ KVM_STATS_LOG_HIST_UPDATE(
+ vcpu->stat.generic.halt_poll_success_hist,
+ ktime_to_ns(ktime_get()) -
+ ktime_to_ns(start));
goto out;
}
cpu_relax();
poll_end = cur = ktime_get();
} while (kvm_vcpu_can_poll(cur, stop));
+
+ KVM_STATS_LOG_HIST_UPDATE(
+ vcpu->stat.generic.halt_poll_fail_hist,
+ ktime_to_ns(ktime_get()) - ktime_to_ns(start));
}
+
prepare_to_rcuwait(&vcpu->wait);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
if (waited) {
vcpu->stat.generic.halt_wait_ns +=
ktime_to_ns(cur) - ktime_to_ns(poll_end);
+ KVM_STATS_LOG_HIST_UPDATE(vcpu->stat.generic.halt_wait_hist,
+ ktime_to_ns(cur) - ktime_to_ns(poll_end));
}
out:
kvm_arch_vcpu_unblocking(vcpu);