vlib: queue_hi_thresh fix to avoid deadlock

[vpp.git] / src / vlib / threads.c

diff --git a/src/vlib/threads.c b/src/vlib/threads.c
index 3f09054..8226379 100644 (file)
--- a/src/vlib/threads.c
+++ b/src/vlib/threads.c
@@ -17,6 +17,7 @@
 #include <signal.h>
 #include <math.h>
 #include <vppinfra/format.h>
+#include <vppinfra/time_range.h>
 #include <vppinfra/linux/sysfs.h>
 #include <vlib/vlib.h>
 
@@ -255,21 +256,6 @@ vlib_thread_init (vlib_main_t * vm)
     }
   avail_cpu = clib_bitmap_set (avail_cpu, tm->main_lcore, 0);
 
-  /*
-   * Determine if the number of workers is greater than 0.
-   * If so, mark CPU 0 unavailable so workers will be numbered after main.
-   */
-  u32 n_workers = 0;
-  uword *p = hash_get_mem (tm->thread_registrations_by_name, "workers");
-  if (p != 0)
-    {
-      vlib_thread_registration_t *tr = (vlib_thread_registration_t *) p[0];
-      int worker_thread_count = tr->count;
-      n_workers = worker_thread_count;
-    }
-  if (tm->skip_cores == 0 && n_workers)
-    avail_cpu = clib_bitmap_set (avail_cpu, 0, 0);
-
   /* assume that there is socket 0 only if there is no data from sysfs */
   if (!tm->cpu_socket_bitmap)
     tm->cpu_socket_bitmap = clib_bitmap_set (0, 0, 1);
@@ -351,12 +337,24 @@ vlib_thread_init (vlib_main_t * vm)
        {
          for (j = 0; j < tr->count; j++)
            {
+             /* Do not use CPU 0 by default - leave it to the host and IRQs */
+             uword avail_c0 = clib_bitmap_get (avail_cpu, 0);
+             avail_cpu = clib_bitmap_set (avail_cpu, 0, 0);
+
              uword c = clib_bitmap_first_set (avail_cpu);
+             /* Use CPU 0 as a last resort */
+             if (c == ~0 && avail_c0)
+               {
+                 c = 0;
+                 avail_c0 = 0;
+               }
+
              if (c == ~0)
                return clib_error_return (0,
                                          "no available cpus to be used for"
                                          " the '%s' thread", tr->name);
 
+             avail_cpu = clib_bitmap_set (avail_cpu, 0, avail_c0);
              avail_cpu = clib_bitmap_set (avail_cpu, c, 0);
              tr->coremask = clib_bitmap_set (tr->coremask, c, 1);
            }
@@ -1298,6 +1296,10 @@ cpu_config (vlib_main_t * vm, unformat_input_t * input)
            return clib_error_return (0,
                                      "corelist cannot be set for '%s' threads",
                                      name);
+         if (tr->count)
+           return clib_error_return
+             (0, "core placement of '%s' threads is already configured",
+              name);
 
          tr->coremask = bitmap;
          tr->count = clib_bitmap_count_set_bits (tr->coremask);
@@ -1316,9 +1318,14 @@ cpu_config (vlib_main_t * vm, unformat_input_t * input)
            return clib_error_return (0, "no such thread type 3 '%s'", name);
 
          tr = (vlib_thread_registration_t *) p[0];
+
          if (tr->fixed_count)
            return clib_error_return
-             (0, "number of %s threads not configurable", tr->name);
+             (0, "number of '%s' threads not configurable", name);
+         if (tr->count)
+           return clib_error_return
+             (0, "number of '%s' threads is already configured", name);
+
          tr->count = count;
        }
       else
@@ -1807,17 +1814,19 @@ vlib_frame_queue_main_init (u32 node_index, u32 frame_queue_nelts)
   vlib_frame_queue_main_t *fqm;
   vlib_frame_queue_t *fq;
   int i;
+  u32 num_threads;
 
   if (frame_queue_nelts == 0)
     frame_queue_nelts = FRAME_QUEUE_MAX_NELTS;
 
-  ASSERT (frame_queue_nelts >= 8);
+  num_threads = 1 /* main thread */  + tm->n_threads;
+  ASSERT (frame_queue_nelts >= 8 + num_threads);
 
   vec_add2 (tm->frame_queue_mains, fqm, 1);
 
   fqm->node_index = node_index;
   fqm->frame_queue_nelts = frame_queue_nelts;
-  fqm->queue_hi_thresh = frame_queue_nelts - 2;
+  fqm->queue_hi_thresh = frame_queue_nelts - num_threads;
 
   vec_validate (fqm->vlib_frame_queues, tm->n_vlib_mains - 1);
   vec_validate (fqm->per_thread_data, tm->n_vlib_mains - 1);
@@ -1890,10 +1899,16 @@ show_clock_command_fn (vlib_main_t * vm,
 {
   int i;
   int verbose = 0;
+  clib_timebase_t _tb, *tb = &_tb;
 
   (void) unformat (input, "verbose %=", &verbose, 1);
 
-  vlib_cli_output (vm, "%U", format_clib_time, &vm->clib_time, verbose);
+  clib_timebase_init (tb, 0 /* GMT */ , CLIB_TIMEBASE_DAYLIGHT_NONE,
+                     &vm->clib_time);
+
+  vlib_cli_output (vm, "%U, %U GMT", format_clib_time, &vm->clib_time,
+                  verbose, format_clib_timebase_time,
+                  clib_timebase_now (tb));
 
   if (vec_len (vlib_mains) == 1)
     return 0;