On 06/07/21 20:03, Jing Zhang wrote:
+#define LINHIST_SIZE_SMALL 10
+#define LINHIST_SIZE_MEDIUM 20
+#define LINHIST_SIZE_LARGE 50
+#define LINHIST_SIZE_XLARGE 100
+#define LINHIST_BUCKET_SIZE_SMALL 10
+#define LINHIST_BUCKET_SIZE_MEDIUM 100
+#define LINHIST_BUCKET_SIZE_LARGE 1000
+#define LINHIST_BUCKET_SIZE_XLARGE 10000
+
+#define LOGHIST_SIZE_SMALL 8
+#define LOGHIST_SIZE_MEDIUM 16
+#define LOGHIST_SIZE_LARGE 32
+#define LOGHIST_SIZE_XLARGE 64
+#define LOGHIST_BASE_2 2
I'd prefer inlining all of these. For log histograms use 2 directly in
STATS_DESC_LOG_HIST, since the update function below uses fls64.
+ */
+void kvm_stats_linear_hist_update(u64 *data, size_t size,
+ u64 value, size_t bucket_size)
+{
+ size_t index = value / bucket_size;
+
+ if (index >= size)
+ index = size - 1;
+ ++data[index];
+}
+
Please make this function always inline, so that the compiler optimizes
the division.
Also please use array_index_nospec to clamp the index to the size, in
case value comes from a memory access as well. Likewise for
kvm_stats_log_hist_update.
Paolo
