perfmon plugin: 2-way parallel stat collection

[vpp.git] / src / plugins / perfmon / perfmon.c

diff --git a/src/plugins/perfmon/perfmon.c b/src/plugins/perfmon/perfmon.c
index c6a8022..3595557 100644 (file)
--- a/src/plugins/perfmon/perfmon.c
+++ b/src/plugins/perfmon/perfmon.c
@@ -157,10 +157,16 @@ perfmon_init (vlib_main_t * vm)
   pm->log_class = vlib_log_register_class ("perfmon", 0);
 
   /* Default data collection interval */
-  pm->timeout_interval = 3.0;
-  vec_validate (pm->pm_fds, vec_len (vlib_mains) - 1);
-  vec_validate (pm->perf_event_pages, vec_len (vlib_mains) - 1);
-  vec_validate (pm->rdpmc_indices, vec_len (vlib_mains) - 1);
+  pm->timeout_interval = 2.0;  /* seconds */
+  vec_validate (pm->pm_fds, 1);
+  vec_validate (pm->pm_fds[0], vec_len (vlib_mains) - 1);
+  vec_validate (pm->pm_fds[1], vec_len (vlib_mains) - 1);
+  vec_validate (pm->perf_event_pages, 1);
+  vec_validate (pm->perf_event_pages[0], vec_len (vlib_mains) - 1);
+  vec_validate (pm->perf_event_pages[1], vec_len (vlib_mains) - 1);
+  vec_validate (pm->rdpmc_indices, 1);
+  vec_validate (pm->rdpmc_indices[0], vec_len (vlib_mains) - 1);
+  vec_validate (pm->rdpmc_indices[1], vec_len (vlib_mains) - 1);
   pm->page_size = getpagesize ();
 
   ht = pm->perfmon_table = 0;
@@ -297,10 +303,12 @@ set_pmc_command_fn (vlib_main_t * vm,
   perfmon_main_t *pm = &perfmon_main;
   unformat_input_t _line_input, *line_input = &_line_input;
   perfmon_event_config_t ec;
+  f64 delay;
   u32 timeout_seconds;
   u32 deadman;
 
-  vec_reset_length (pm->events_to_collect);
+  vec_reset_length (pm->single_events_to_collect);
+  vec_reset_length (pm->paired_events_to_collect);
   pm->ipc_event_index = ~0;
   pm->mispredict_event_index = ~0;
 
@@ -316,28 +324,28 @@ set_pmc_command_fn (vlib_main_t * vm,
          ec.name = "instructions";
          ec.pe_type = PERF_TYPE_HARDWARE;
          ec.pe_config = PERF_COUNT_HW_INSTRUCTIONS;
-         pm->ipc_event_index = vec_len (pm->events_to_collect);
-         vec_add1 (pm->events_to_collect, ec);
+         pm->ipc_event_index = vec_len (pm->paired_events_to_collect);
+         vec_add1 (pm->paired_events_to_collect, ec);
          ec.name = "cpu-cycles";
          ec.pe_type = PERF_TYPE_HARDWARE;
          ec.pe_config = PERF_COUNT_HW_CPU_CYCLES;
-         vec_add1 (pm->events_to_collect, ec);
+         vec_add1 (pm->paired_events_to_collect, ec);
        }
       else if (unformat (line_input, "branch-mispredict-rate"))
        {
          ec.name = "branch-misses";
          ec.pe_type = PERF_TYPE_HARDWARE;
          ec.pe_config = PERF_COUNT_HW_BRANCH_MISSES;
-         pm->mispredict_event_index = vec_len (pm->events_to_collect);
-         vec_add1 (pm->events_to_collect, ec);
+         pm->mispredict_event_index = vec_len (pm->paired_events_to_collect);
+         vec_add1 (pm->paired_events_to_collect, ec);
          ec.name = "branches";
          ec.pe_type = PERF_TYPE_HARDWARE;
          ec.pe_config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
-         vec_add1 (pm->events_to_collect, ec);
+         vec_add1 (pm->paired_events_to_collect, ec);
        }
       else if (unformat (line_input, "%U", unformat_processor_event, pm, &ec))
        {
-         vec_add1 (pm->events_to_collect, ec);
+         vec_add1 (pm->single_events_to_collect, ec);
        }
 #define _(type,event,str)                       \
       else if (unformat (line_input, str))      \
@@ -345,7 +353,7 @@ set_pmc_command_fn (vlib_main_t * vm,
           ec.name = str;                        \
           ec.pe_type = type;                    \
           ec.pe_config = event;                 \
-          vec_add1 (pm->events_to_collect, ec); \
+          vec_add1 (pm->single_events_to_collect, ec); \
         }
       foreach_perfmon_event
 #undef _
@@ -354,21 +362,33 @@ set_pmc_command_fn (vlib_main_t * vm,
                                  format_unformat_error, line_input);
     }
 
-  if (vec_len (pm->events_to_collect) == 0)
+  /* Stick paired events at the front of the (unified) list */
+  if (vec_len (pm->paired_events_to_collect) > 0)
+    {
+      perfmon_event_config_t *tmp;
+      /* first 2n events are pairs... */
+      vec_append (pm->paired_events_to_collect, pm->single_events_to_collect);
+      tmp = pm->single_events_to_collect;
+      pm->single_events_to_collect = pm->paired_events_to_collect;
+      pm->paired_events_to_collect = tmp;
+    }
+
+  if (vec_len (pm->single_events_to_collect) == 0)
     return clib_error_return (0, "no events specified...");
 
+  /* Figure out how long data collection will take */
+  delay =
+    ((f64) vec_len (pm->single_events_to_collect)) * pm->timeout_interval;
+  delay /= 2.0;                        /* collect 2 stats at once */
+
   vlib_cli_output (vm, "Start collection for %d events, wait %.2f seconds",
-                  vec_len (pm->events_to_collect),
-                  (f64) (vec_len (pm->events_to_collect))
-                  * pm->timeout_interval);
+                  vec_len (pm->single_events_to_collect), delay);
 
   vlib_process_signal_event (pm->vlib_main, perfmon_periodic_node.index,
                             PERFMON_START, 0);
 
   /* Coarse-grained wait */
-  vlib_process_suspend (vm,
-                       ((f64) (vec_len (pm->events_to_collect)
-                               * pm->timeout_interval)));
+  vlib_process_suspend (vm, delay);
 
   deadman = 0;
   /* Reasonable to guess that collection may not be quite done... */
@@ -438,7 +458,7 @@ format_capture (u8 * s, va_list * args)
       if (i == pm->ipc_event_index)
        {
          f64 ipc_rate;
-         ASSERT (i + 1 < vec_len (c->counter_names));
+         ASSERT ((i + 1) < vec_len (c->counter_names));
 
          if (c->counter_values[i + 1] > 0)
            ipc_rate = (f64) c->counter_values[i]