MEDIUM: thread: change thread_resolve_group_mask() to return group-local values

It used to turn group+local to global but now we're doing the exact
opposite as we want to stick to group-local masks. This means that
"thread 3-4" might very well emit what "thread 2/1-2" used to emit
till now for 2 groups and 4 threads. This is needed because we'll
have to support group-local thread masks in receivers.

However the rest of the code (receivers) is not ready yet for this,
so using this code with more than one thread group will definitely
break some bindings.

diff --git a/src/thread.c b/src/thread.c
index 9c8b234797cb6b5a6a350115384dcc2a4a5697d3..e38b7fea9741f8186815c42e99c84705ef81ce09 100644 (file)
--- a/src/thread.c
+++ b/src/thread.c
@@ -1133,16 +1133,17 @@ int thread_map_to_groups()
        return 0;
 }
 
-/* converts a configuration thread group+mask to a global group+mask depending on
- * the configured thread group id. This is essentially for use with the "thread"
- * directive on "bind" lines, where "thread 2/1-3" might be turned to "4-6" for
- * the global ID. It cannot be used before the thread mapping above was completed
- * and the thread group number configured. Possible options:
+/* converts a configuration thread num or group+mask to a global group+mask
+ * depending on the configured thread group id. This is essentially for use
+ * with the "thread" directive on "bind" lines, where "thread 4-6" might be
+ * turned to "2/1-3". It cannot be used before the thread mapping above was
+ * completed and the thread group number configured. Possible options:
  *  - igid == 0: imask represents global IDs. We have to check that all
  *    configured threads in the mask belong to the same group. If imask is zero
  *    it means everything, so for now we only support this with a single group.
- *  - igid > 0, imask = 0: convert local values to global values for this thread
- *  - igid > 0, imask > 0: convert local values to global values
+ *  - igid > 0, imask = 0: convert global values to local values for this thread
+ *  - igid > 0, imask > 0: convert global values to local values
+ * Note that the output mask is always local to the group.
  *
  * Returns <0 on failure, >=0 on success.
  */
@@ -1159,13 +1160,11 @@ int thread_resolve_group_mask(uint igid, ulong imask, uint *ogid, ulong *omask,
                                memprintf(err, "'thread' directive spans multiple groups");
                                return -1;
                        }
-                       mask = 0;
                        *ogid = 1; // first and only group
-                       *omask = all_threads_mask;
+                       *omask = ha_tgroup_info[0].threads_enabled;
                        return 0;
                } else {
                        /* some global threads */
-                       imask &= all_threads_mask;
                        for (t = 0; t < global.nbthread; t++) {
                                if (imask & (1UL << t)) {
                                        if (ha_thread_info[t].tgid != igid) {
@@ -1186,7 +1185,9 @@ int thread_resolve_group_mask(uint igid, ulong imask, uint *ogid, ulong *omask,
 
                        /* we have a valid group, convert this to global thread IDs */
                        *ogid = igid;
-                       *omask = imask & (ha_tgroup_info[igid - 1].threads_enabled << ha_tgroup_info[igid - 1].base);
+                       imask = imask >> ha_tgroup_info[igid - 1].base;
+                       imask &= ha_tgroup_info[igid - 1].threads_enabled;
+                       *omask = imask;
                        return 0;
                }
        } else {
@@ -1199,15 +1200,12 @@ int thread_resolve_group_mask(uint igid, ulong imask, uint *ogid, ulong *omask,
                if (!imask) {
                        /* all threads of this groups. Let's make a mask from their count and base. */
                        *ogid = igid;
-                       mask = 1UL << (ha_tgroup_info[igid - 1].count - 1);
-                       mask |= mask - 1;
-                       *omask = mask << ha_tgroup_info[igid - 1].base;
+                       *omask = nbits(ha_tgroup_info[igid - 1].count);
                        return 0;
                } else {
                        /* some local threads. Keep only existing ones for this group */
 
-                       mask = 1UL << (ha_tgroup_info[igid - 1].count - 1);
-                       mask |= mask - 1;
+                       mask = nbits(ha_tgroup_info[igid - 1].count);
 
                        if (!(mask & imask)) {
                                /* no intersection between the thread group's
@@ -1227,8 +1225,7 @@ int thread_resolve_group_mask(uint igid, ulong imask, uint *ogid, ulong *omask,
 #endif
                        }
 
-                       mask &= imask;
-                       *omask = mask << ha_tgroup_info[igid - 1].base;
+                       *omask = mask & imask;
                        *ogid = igid;
                        return 0;
                }