erts: Refactor perf counter internal interface

perf counter is now part of the function pointer interface
and also the function returns the value instead of writing
to a memory buffer.

5 files changed, 16 insertions, 78 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index 4be311ae82..9f143c22bf 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -4938,10 +4938,10 @@ do {						\
     it has to be very very fast */
  OpCase(i_perf_counter): {
     BeamInstr* next;
-    ErtsSysHrTime ts;
+    ErtsSysPerfCounter ts;
     PreFetch(0, next);
 
-    sys_perf_counter(&ts);
+    ts = erts_sys_perf_counter();
 
     if (IS_SSMALL(ts)) {
         r(0) = make_small((Sint)ts);
diff --git a/erts/emulator/beam/erl_msacc.c b/erts/emulator/beam/erl_msacc.c
index bf1c06dea7..71e3fd8b6e 100644
--- a/erts/emulator/beam/erl_msacc.c
+++ b/erts/emulator/beam/erl_msacc.c
@@ -117,7 +117,7 @@ void erts_msacc_init_thread(char *type, int id, int managed) {
 
 #ifdef ERTS_MSACC_ALWAYS_ON
     ERTS_MSACC_TSD_SET(msacc);
-    sys_perf_counter(&msacc->perf_counter);
+    msacc->perf_counter = erts_sys_perf_counter();
     msacc->state = ERTS_MSACC_STATE_OTHER;
 #endif
 }
@@ -278,7 +278,7 @@ reply_msacc(void *vmsaccrp)
     if (msaccrp->action == ERTS_MSACC_ENABLE && !msacc) {
         msacc = get_msacc();
 
-        sys_perf_counter(&msacc->perf_counter);
+        msacc->perf_counter = erts_sys_perf_counter();
 
         msacc->state = ERTS_MSACC_STATE_OTHER;
 
@@ -412,9 +412,9 @@ erts_msacc_request(Process *c_p, int action, Eterm *threads)
         for (i = 0; i < unmanaged_count; i++) {
             erts_mtx_lock(&unmanaged[i]->mtx);
             if (unmanaged[i]->perf_counter) {
-                ErtsSysHrTime perf_counter;
+                ErtsSysPerfCounter perf_counter;
                 /* if enabled update stats */
-                sys_perf_counter(&perf_counter);
+                perf_counter = erts_sys_perf_counter();
                 unmanaged[i]->perf_counters[unmanaged[i]->state] +=
                     perf_counter - unmanaged[i]->perf_counter;
                 unmanaged[i]->perf_counter = perf_counter;
@@ -439,7 +439,7 @@ erts_msacc_request(Process *c_p, int action, Eterm *threads)
         erts_rwmtx_rlock(&msacc_mutex);
         for (msacc = msacc_unmanaged; msacc != NULL; msacc = msacc->next) {
             erts_mtx_lock(&msacc->mtx);
-            sys_perf_counter(&msacc->perf_counter);
+            msacc->perf_counter = erts_sys_perf_counter();
             /* we assume the unmanaged thread is sleeping */
             msacc->state = ERTS_MSACC_STATE_SLEEP;
             erts_mtx_unlock(&msacc->mtx);
@@ -448,12 +448,12 @@ erts_msacc_request(Process *c_p, int action, Eterm *threads)
         break;
     }
     case ERTS_MSACC_DISABLE: {
-        ErtsSysHrTime perf_counter;
+        ErtsSysPerfCounter perf_counter;
         erts_rwmtx_rlock(&msacc_mutex);
         /* make sure to update stats with latest results */
         for (msacc = msacc_unmanaged; msacc != NULL; msacc = msacc->next) {
             erts_mtx_lock(&msacc->mtx);
-            sys_perf_counter(&perf_counter);
+            perf_counter = erts_sys_perf_counter();
             msacc->perf_counters[msacc->state] += perf_counter - msacc->perf_counter;
             msacc->perf_counter = 0;
             erts_mtx_unlock(&msacc->mtx);
diff --git a/erts/emulator/beam/erl_msacc.h b/erts/emulator/beam/erl_msacc.h
index 1b4b7a408a..284388f7aa 100644
--- a/erts/emulator/beam/erl_msacc.h
+++ b/erts/emulator/beam/erl_msacc.h
@@ -121,8 +121,8 @@ typedef struct erl_msacc_t_ ErtsMsAcc;
 struct erl_msacc_t_ {
 
     /* the the values below are protected by mtx iff unmanaged = 1 */
-    ErtsSysHrTime perf_counter;
-    ErtsSysHrTime perf_counters[ERTS_MSACC_STATE_COUNT];
+    ErtsSysPerfCounter perf_counter;
+    ErtsSysPerfCounter perf_counters[ERTS_MSACC_STATE_COUNT];
 #ifdef ERTS_MSACC_STATE_COUNTERS
     Uint64 state_counters[ERTS_MSACC_STATE_COUNT];
 #endif
@@ -324,14 +324,14 @@ void erts_msacc_set_state_um__(ErtsMsAcc *msacc, Uint new_state, int increment)
 
 ERTS_MSACC_INLINE
 void erts_msacc_set_state_m__(ErtsMsAcc *msacc, Uint new_state, int increment) {
-    ErtsSysHrTime prev_perf_counter;
+    ErtsSysPerfCounter prev_perf_counter;
     Sint64 diff;
 
     if (new_state == msacc->state)
         return;
 
     prev_perf_counter = msacc->perf_counter;
-    sys_perf_counter(&msacc->perf_counter);
+    msacc->perf_counter = erts_sys_perf_counter();
     diff = msacc->perf_counter - prev_perf_counter;
     ASSERT(diff >= 0);
     msacc->perf_counters[msacc->state] += diff;
diff --git a/erts/emulator/beam/erl_time.h b/erts/emulator/beam/erl_time.h
index 446adcf4af..5242063550 100644
--- a/erts/emulator/beam/erl_time.h
+++ b/erts/emulator/beam/erl_time.h
@@ -142,7 +142,7 @@ erts_time_unit_conversion(Uint64 value,
 			  Uint32 from_time_unit,
 			  Uint32 to_time_unit);
 
-ErtsSysHrTime erts_perf_counter_unit(void);
+ErtsSysPerfCounter erts_perf_counter_unit(void);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
diff --git a/erts/emulator/beam/erl_time_sup.c b/erts/emulator/beam/erl_time_sup.c
index 6509c6a805..98159fdf72 100644
--- a/erts/emulator/beam/erl_time_sup.c
+++ b/erts/emulator/beam/erl_time_sup.c
@@ -2444,72 +2444,10 @@ BIF_RETTYPE os_system_time_1(BIF_ALIST_1)
 BIF_RETTYPE
 os_perf_counter_0(BIF_ALIST_0)
 {
-    ErtsSysHrTime pcounter;
-    sys_perf_counter(&pcounter);
-    BIF_RET(make_time_val(BIF_P, pcounter));
+    BIF_RET(make_time_val(BIF_P, erts_sys_perf_counter()));
 }
 
 BIF_RETTYPE erts_internal_perf_counter_unit_0(BIF_ALIST_0)
 {
-    BIF_RET(make_time_val(BIF_P, SYS_PERF_COUNTER_UNIT));
-}
-
-/* What resolution to spin to in micro seconds */
-#define RESOLUTION 100
-/* How many iterations to spin */
-#define ITERATIONS 1
-/* How many significant figures to round to */
-#define SIGFIGS 3
-
-static ErtsSysHrTime perf_counter_unit = 0;
-
-static ErtsSysHrTime erts_calculate_perf_counter_unit(void);
-static ErtsSysHrTime erts_calculate_perf_counter_unit() {
-    int i;
-    ErtsSysHrTime pre, post;
-    double value = 0;
-    double round_factor;
-#if defined(HAVE_GETHRTIME) && defined(GETHRTIME_WITH_CLOCK_GETTIME)
-    struct timespec basetime,comparetime;
-#define __GETTIME(arg) clock_gettime(CLOCK_MONOTONIC,arg)
-#define __GETUSEC(arg) (arg.tv_nsec / 1000)
-#else
-    SysTimeval basetime,comparetime;
-#define __GETTIME(arg) sys_gettimeofday(arg)
-#define __GETUSEC(arg) arg.tv_usec
-#endif
-
-    for (i = 0; i < ITERATIONS; i++) {
-        /* Make sure usec just flipped over at current resolution */
-        __GETTIME(&basetime);
-        do {
-            __GETTIME(&comparetime);
-        } while ((__GETUSEC(basetime) / RESOLUTION) == (__GETUSEC(comparetime) / RESOLUTION));
-
-        sys_perf_counter(&pre);
-
-        __GETTIME(&basetime);
-        do {
-            __GETTIME(&comparetime);
-        } while ((__GETUSEC(basetime) / RESOLUTION) == (__GETUSEC(comparetime) / RESOLUTION));
-
-        sys_perf_counter(&post);
-
-        value += post - pre;
-    }
-    /* After this value is ticks per us */
-    value /= (RESOLUTION*ITERATIONS);
-
-    /* We round to 3 significant figures */
-    round_factor = pow(10.0, SIGFIGS - ceil(log10(value)));
-    value = ((ErtsSysHrTime)(value * round_factor + 0.5)) / round_factor;
-
-    /* convert to ticks per second */
-    return 1000000 * value;
-}
-
-ErtsSysHrTime erts_perf_counter_unit() {
-    if (perf_counter_unit == 0)
-        perf_counter_unit = erts_calculate_perf_counter_unit();
-    return perf_counter_unit;
+    BIF_RET(make_time_val(BIF_P, erts_sys_perf_counter_unit()));
 }