gru: check for correct GRU chiplet assignment

Simplify the code that checks for correct assignment of GRU contexts to
users.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 30 insertions, 14 deletions

diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index ade0925eab0e..f8538bbd0bfa 100644
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -53,12 +53,16 @@ struct device *grudev = &gru_device;
  */
 int gru_cpu_fault_map_id(void)
 {
+#ifdef CONFIG_IA64
+        return uv_blade_processor_id() % GRU_NUM_TFM;
+#else
         int cpu = smp_processor_id();
         int id, core;
 
         core = uv_cpu_core_number(cpu);
         id = core + UV_MAX_INT_CORES * uv_cpu_socket_number(cpu);
         return id;
+#endif
 }
 
 /*--------- ASID Management -------------------------------------------
@@ -699,15 +703,34 @@ static int gru_retarget_intr(struct gru_thread_state *gts)
 }
 
 /*
+ * Check if a GRU context is allowed to use a specific chiplet. By default
+ * a context is assigned to any blade-local chiplet. However, users can
+ * override this.
+ *      Returns 1 if assignment allowed, 0 otherwise
+ */
+static int gru_check_chiplet_assignment(struct gru_state *gru,
+                                        struct gru_thread_state *gts)
+{
+        int blade_id;
+        int chiplet_id;
+
+        blade_id = gts->ts_user_blade_id;
+        if (blade_id < 0)
+                blade_id = uv_numa_blade_id();
+
+        chiplet_id = gts->ts_user_chiplet_id;
+        return gru->gs_blade_id == blade_id &&
+                (chiplet_id < 0 || chiplet_id == gru->gs_chiplet_id);
+}
+
+/*
  * Unload the gru context if it is not assigned to the correct blade or
  * chiplet. Misassignment can occur if the process migrates to a different
  * blade or if the user changes the selected blade/chiplet.
- *      Return 0 if  context correct placed, otherwise 1
  */
 void gru_check_context_placement(struct gru_thread_state *gts)
 {
         struct gru_state *gru;
-        int blade_id, chiplet_id;
 
         /*
          * If the current task is the context owner, verify that the
@@ -718,13 +741,7 @@ void gru_check_context_placement(struct gru_thread_state *gts)
         if (!gru || gts->ts_tgid_owner != current->tgid)
                 return;
 
-        blade_id = gts->ts_user_blade_id;
-        if (blade_id < 0)
-                blade_id = uv_numa_blade_id();
-
-        chiplet_id = gts->ts_user_chiplet_id;
-        if (gru->gs_blade_id != blade_id ||
-            (chiplet_id >= 0 && chiplet_id != gru->gs_chiplet_id)) {
+        if (!gru_check_chiplet_assignment(gru, gts)) {
                 STAT(check_context_unload);
                 gru_unload_context(gts, 1);
         } else if (gru_retarget_intr(gts)) {
@@ -768,9 +785,9 @@ void gru_steal_context(struct gru_thread_state *gts)
         struct gru_state *gru, *gru0;
         struct gru_thread_state *ngts = NULL;
         int ctxnum, ctxnum0, flag = 0, cbr, dsr;
-        int blade_id = gts->ts_user_blade_id;
-        int chiplet_id = gts->ts_user_chiplet_id;
+        int blade_id;
 
+        blade_id = gts->ts_user_blade_id;
         if (blade_id < 0)
                 blade_id = uv_numa_blade_id();
         cbr = gts->ts_cbr_au_count;
@@ -788,7 +805,7 @@ void gru_steal_context(struct gru_thread_state *gts)
         ctxnum0 = ctxnum;
         gru0 = gru;
         while (1) {
-                if (chiplet_id < 0 || chiplet_id == gru->gs_chiplet_id) {
+                if (gru_check_chiplet_assignment(gru, gts)) {
                         if (check_gru_resources(gru, cbr, dsr, GRU_NUM_CCH))
                                 break;
                         spin_lock(&gru->gs_lock);
@@ -853,7 +870,6 @@ struct gru_state *gru_assign_gru_context(struct gru_thread_state *gts)
         struct gru_state *gru, *grux;
         int i, max_active_contexts;
         int blade_id = gts->ts_user_blade_id;
-        int chiplet_id = gts->ts_user_chiplet_id;
 
         if (blade_id < 0)
                 blade_id = uv_numa_blade_id();
@@ -861,7 +877,7 @@ again:
         gru = NULL;
         max_active_contexts = GRU_NUM_CCH;
         for_each_gru_on_blade(grux, blade_id, i) {
-                if (chiplet_id >= 0 && chiplet_id != grux->gs_chiplet_id)
+                if (!gru_check_chiplet_assignment(grux, gts))
                         continue;
                 if (check_gru_resources(grux, gts->ts_cbr_au_count,
                                         gts->ts_dsr_au_count,