1 files changed, 94 insertions, 0 deletions
diff --git a/benchmarks/harness.h b/benchmarks/harness.h
new file mode 100644
index 0000000..72164b4
--- /dev/null
+++ b/benchmarks/harness.h
@@ -0,0 +1,94 @@
+#include <stdint.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static uint64_t time_get_ns (void) {
+    struct timespec ts;
+    clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
+    return (uint64_t)ts.tv_sec * 1000UL*1000UL*1000UL + (uint64_t)ts.tv_nsec;
+}
+
+uint64_t read_energy_uj (void) {
+    FILE *f = fopen("/sys/class/powercap/intel-rapl/intel-rapl:0/energy_uj", "r");
+    if (!f) {
+        perror("Failed to open energy counter (Are you running with sudo?)");
+        return 0;
+    }
+    uint64_t energy;
+    if (fscanf(f, "%lu", &energy) != 1) {
+        energy = 0;
+    }
+    fclose(f);
+    return energy;
+}
+
+#define BLACK_BOX(x) \
+    __asm__ __volatile__("" : "+g"(x))
+
+#define MIN(A,B) (A) < (B) ? (A) : (B)
+
+void bench_ (
+    char const* const name,
+    #ifdef CONST_BUFFER
+    size_t(*f)(char const*, size_t),
+    char const* buffer,
+    #else
+    size_t(*f)(char*, size_t),
+    char* buffer,
+    #endif
+    size_t buffer_size,
+    FILE* out
+) {
+    int64_t budget = 5UL*1000UL*1000UL*1000UL;
+
+    uint64_t best = UINT64_MAX;
+    uint64_t best_energy = UINT64_MAX;
+
+    #ifndef CONST_BUFFER
+    char* const tmp_buf = (char*)malloc(buffer_size);
+    memcpy(tmp_buf, buffer, buffer_size);
+    #endif
+
+    uint64_t res = f(buffer, buffer_size);
+
+    fprintf(out,
+        "  <benchmark name=\"%s\">\n"
+        "    <res>%zu</res>\n",
+        name,
+        res
+    );
+
+    while (budget > 0) {
+        #ifndef CONST_BUFFER
+        memcpy(buffer, tmp_buf, buffer_size);
+        #endif
+        uint64_t start_energy = read_energy_uj();
+        uint64_t start = time_get_ns();
+        res = f(buffer, buffer_size);
+        uint64_t elapsed = time_get_ns() - start;
+        best = MIN(best, elapsed);
+        best_energy = MIN(best_energy, read_energy_uj() - start_energy);
+        budget -= elapsed;
+        BLACK_BOX(res);
+    }
+
+    fprintf(out,
+        "    <time unit=\"ns\">%zu</time>\n"
+        "    <throughput unit=\"MiB/s\">%f</throughput>\n",
+        best,
+        ((double)(buffer_size) / (1024.0*1024.0)) / ((double)(best) / (1000.0*1000.0*1000.0))
+    );
+
+    if (best_energy != 0) {
+        fprintf(out,
+            "    <energy-consumption unit=\"J/GiB\">%f</energy-consumption>\n",
+            ((double)(best_energy) / (1000.0*1000.0)) / ((double)(buffer_size) / (1024.0*1024.0*1024.0))
+        );
+    }
+    fprintf(out, "  </benchmark>\n");
+}
+
+#define bench(FN) bench_(#FN, FN, buffer, buf_size, out)
+