From 1b870fa5573e260bc74d19f381ab0dd971a8d8e7 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 14 Jul 2022 07:27:31 -0400 Subject: kvm: stats: tell userspace which values are boolean Some of the statistics values exported by KVM are always only 0 or 1. It can be useful to export this fact to userspace so that it can track them specially (for example by polling the value every now and then to compute a % of time spent in a specific state). Therefore, add "boolean value" as a new "unit". While it is not exactly a unit, it walks and quacks like one. In particular, using the type would be wrong because boolean values could be instantaneous or peak values (e.g. "is the rmap allocated?") or even two-bucket histograms (e.g. "number of posted vs. non-posted interrupt injections"). Suggested-by: Amneesh Singh Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'include/linux/kvm_host.h') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 83cf7fd842e0..90a45ef7203b 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1822,6 +1822,15 @@ struct _kvm_stats_desc { STATS_DESC_PEAK(SCOPE, name, KVM_STATS_UNIT_NONE, \ KVM_STATS_BASE_POW10, 0) +/* Instantaneous boolean value, read only */ +#define STATS_DESC_IBOOLEAN(SCOPE, name) \ + STATS_DESC_INSTANT(SCOPE, name, KVM_STATS_UNIT_BOOLEAN, \ + KVM_STATS_BASE_POW10, 0) +/* Peak (sticky) boolean value, read/write */ +#define STATS_DESC_PBOOLEAN(SCOPE, name) \ + STATS_DESC_PEAK(SCOPE, name, KVM_STATS_UNIT_BOOLEAN, \ + KVM_STATS_BASE_POW10, 0) + /* Cumulative time in nanosecond */ #define STATS_DESC_TIME_NSEC(SCOPE, name) \ STATS_DESC_CUMULATIVE(SCOPE, name, KVM_STATS_UNIT_SECONDS, \ @@ -1853,7 +1862,7 @@ struct _kvm_stats_desc { HALT_POLL_HIST_COUNT), \ STATS_DESC_LOGHIST_TIME_NSEC(VCPU_GENERIC, halt_wait_hist, \ HALT_POLL_HIST_COUNT), \ - STATS_DESC_ICOUNTER(VCPU_GENERIC, blocking) + STATS_DESC_IBOOLEAN(VCPU_GENERIC, blocking) extern struct dentry *kvm_debugfs_dir; -- cgit v1.2.3