remove perfctr support

Perfctr is a Linux kernel extension that allows programmatic access
to the performance monitoring counters found in most current CPUs.
However, development of perfctr ceased after 2010, and it cannot be
used with Linux kernels newer than 2.6.32.

Therefore the perfctr support code in the Erlang VM is effectively
dead code, so this patch removes it.

1 files changed, 1 insertions, 64 deletions

diff --git a/erts/emulator/beam/benchmark.c b/erts/emulator/beam/benchmark.c
index 8613131176..b16fe6b271 100644
--- a/erts/emulator/beam/benchmark.c
+++ b/erts/emulator/beam/benchmark.c
@@ -37,37 +37,9 @@ unsigned long long major_gc;
 
 #ifdef BM_TIMERS
 
-#if (defined(__i386__) || defined(__x86_64__)) && USE_PERFCTR
-
-#include "libperfctr.h"
-struct vperfctr *system_clock;
-double cpu_khz;
-BM_NEW_TIMER(start);
-
-static double get_hrvtime(void)
-{
-    unsigned long long ticks;
-    double milli_seconds;
-
-    ticks = vperfctr_read_tsc(system_clock);
-    milli_seconds = (double)ticks / cpu_khz;
-    return milli_seconds;
-}
-
-static void stop_hrvtime(void)
-{
-    if(system_clock)
-    {
-	vperfctr_stop(system_clock);
-	vperfctr_close(system_clock);
-	system_clock = NULL;
-    }
-}
-
-#else /* not perfctr, asuming Solaris */
+/* assuming Solaris */
 #include <time.h>
 BM_TIMER_T system_clock;
-#endif
 
 unsigned long local_pause_times[MAX_PAUSE_TIME];
 unsigned long pause_times[MAX_PAUSE_TIME];
@@ -117,40 +89,6 @@ unsigned long long message_sizes[1000];
 void init_benchmarking()
 {
 #ifdef BM_TIMERS
-#if (defined(__i386__) || defined(__x86_64__)) && USE_PERFCTR
-    /* pass `--with-perfctr=/path/to/perfctr' when configuring */
-    struct perfctr_info info;
-    struct vperfctr_control control;
-    int i;
-
-    system_clock = vperfctr_open();
-    if (system_clock != NULL)
-    {
-        if (vperfctr_info(system_clock,&info) >= 0)
-        {
-            cpu_khz = (double)info.cpu_khz;
-            if (info.cpu_features & PERFCTR_FEATURE_RDTSC)
-            {
-                memset(&control,0,sizeof control);
-                control.cpu_control.tsc_on = 1;
-            }
-        }
-        if (vperfctr_control(system_clock,&control) < 0)
-        {
-            vperfctr_close(system_clock);
-            system_clock = NULL;
-        }
-    }
-
-    for (i = 0; i < 1000; i++)
-    {
-        BM_START_TIMER(system);
-        BM_STOP_TIMER(system);
-    }
-
-    timer_time = system_time / 1000;
-    start_time = 0;
-#else
     int i;
     for (i = 0; i < 1000; i++)
     {
@@ -158,7 +96,6 @@ void init_benchmarking()
         BM_STOP_TIMER(system);
     }
     timer_time = system_time / 1000;
-#endif
 
     for (i = 0; i < MAX_PAUSE_TIME; i++) {
         local_pause_times[i] = 0;