aboutsummaryrefslogtreecommitdiff
path: root/drivers/misc/sgi-gru/grumain.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/misc/sgi-gru/grumain.c')
-rw-r--r--drivers/misc/sgi-gru/grumain.c128
1 files changed, 86 insertions, 42 deletions
diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index f449c2dbc1e..54ad7544a9a 100644
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -684,6 +684,40 @@ static int gru_retarget_intr(struct gru_thread_state *gts)
return gru_update_cch(gts, 0);
}
+/*
+ * 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
+ * context is correctly placed. This test is skipped for non-owner
+ * references. Pthread apps use non-owner references to the CBRs.
+ */
+ gru = gts->ts_gru;
+ 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)) {
+ STAT(check_context_unload);
+ gru_unload_context(gts, 1);
+ } else if (gru_retarget_intr(gts)) {
+ STAT(check_context_retarget_intr);
+ }
+}
+
/*
* Insufficient GRU resources available on the local blade. Steal a context from
@@ -714,13 +748,17 @@ static void gts_stolen(struct gru_thread_state *gts,
}
}
-void gru_steal_context(struct gru_thread_state *gts, int blade_id)
+void gru_steal_context(struct gru_thread_state *gts)
{
struct gru_blade_state *blade;
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;
+ if (blade_id < 0)
+ blade_id = uv_numa_blade_id();
cbr = gts->ts_cbr_au_count;
dsr = gts->ts_dsr_au_count;
@@ -731,35 +769,39 @@ void gru_steal_context(struct gru_thread_state *gts, int blade_id)
gru = blade->bs_lru_gru;
if (ctxnum == 0)
gru = next_gru(blade, gru);
+ blade->bs_lru_gru = gru;
+ blade->bs_lru_ctxnum = ctxnum;
ctxnum0 = ctxnum;
gru0 = gru;
while (1) {
- if (check_gru_resources(gru, cbr, dsr, GRU_NUM_CCH))
- break;
- spin_lock(&gru->gs_lock);
- for (; ctxnum < GRU_NUM_CCH; ctxnum++) {
- if (flag && gru == gru0 && ctxnum == ctxnum0)
+ if (chiplet_id < 0 || chiplet_id == gru->gs_chiplet_id) {
+ if (check_gru_resources(gru, cbr, dsr, GRU_NUM_CCH))
break;
- ngts = gru->gs_gts[ctxnum];
- /*
- * We are grabbing locks out of order, so trylock is
- * needed. GTSs are usually not locked, so the odds of
- * success are high. If trylock fails, try to steal a
- * different GSEG.
- */
- if (ngts && is_gts_stealable(ngts, blade))
+ spin_lock(&gru->gs_lock);
+ for (; ctxnum < GRU_NUM_CCH; ctxnum++) {
+ if (flag && gru == gru0 && ctxnum == ctxnum0)
+ break;
+ ngts = gru->gs_gts[ctxnum];
+ /*
+ * We are grabbing locks out of order, so trylock is
+ * needed. GTSs are usually not locked, so the odds of
+ * success are high. If trylock fails, try to steal a
+ * different GSEG.
+ */
+ if (ngts && is_gts_stealable(ngts, blade))
+ break;
+ ngts = NULL;
+ }
+ spin_unlock(&gru->gs_lock);
+ if (ngts || (flag && gru == gru0 && ctxnum == ctxnum0))
break;
- ngts = NULL;
- flag = 1;
}
- spin_unlock(&gru->gs_lock);
- if (ngts || (flag && gru == gru0 && ctxnum == ctxnum0))
+ if (flag && gru == gru0)
break;
+ flag = 1;
ctxnum = 0;
gru = next_gru(blade, gru);
}
- blade->bs_lru_gru = gru;
- blade->bs_lru_ctxnum = ctxnum;
spin_unlock(&blade->bs_lock);
if (ngts) {
@@ -778,19 +820,35 @@ void gru_steal_context(struct gru_thread_state *gts, int blade_id)
}
/*
+ * Assign a gru context.
+ */
+static int gru_assign_context_number(struct gru_state *gru)
+{
+ int ctxnum;
+
+ ctxnum = find_first_zero_bit(&gru->gs_context_map, GRU_NUM_CCH);
+ __set_bit(ctxnum, &gru->gs_context_map);
+ return ctxnum;
+}
+
+/*
* Scan the GRUs on the local blade & assign a GRU context.
*/
-struct gru_state *gru_assign_gru_context(struct gru_thread_state *gts,
- int blade)
+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();
again:
gru = NULL;
max_active_contexts = GRU_NUM_CCH;
- for_each_gru_on_blade(grux, blade, i) {
+ for_each_gru_on_blade(grux, blade_id, i) {
+ if (chiplet_id >= 0 && chiplet_id != grux->gs_chiplet_id)
+ continue;
if (check_gru_resources(grux, gts->ts_cbr_au_count,
gts->ts_dsr_au_count,
max_active_contexts)) {
@@ -811,12 +869,9 @@ again:
reserve_gru_resources(gru, gts);
gts->ts_gru = gru;
gts->ts_blade = gru->gs_blade_id;
- gts->ts_ctxnum =
- find_first_zero_bit(&gru->gs_context_map, GRU_NUM_CCH);
- BUG_ON(gts->ts_ctxnum == GRU_NUM_CCH);
+ gts->ts_ctxnum = gru_assign_context_number(gru);
atomic_inc(&gts->ts_refcnt);
gru->gs_gts[gts->ts_ctxnum] = gts;
- __set_bit(gts->ts_ctxnum, &gru->gs_context_map);
spin_unlock(&gru->gs_lock);
STAT(assign_context);
@@ -844,7 +899,6 @@ int gru_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct gru_thread_state *gts;
unsigned long paddr, vaddr;
- int blade_id;
vaddr = (unsigned long)vmf->virtual_address;
gru_dbg(grudev, "vma %p, vaddr 0x%lx (0x%lx)\n",
@@ -859,28 +913,18 @@ int gru_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
again:
mutex_lock(&gts->ts_ctxlock);
preempt_disable();
- blade_id = uv_numa_blade_id();
- if (gts->ts_gru) {
- if (gts->ts_gru->gs_blade_id != blade_id) {
- STAT(migrated_nopfn_unload);
- gru_unload_context(gts, 1);
- } else {
- if (gru_retarget_intr(gts))
- STAT(migrated_nopfn_retarget);
- }
- }
+ gru_check_context_placement(gts);
if (!gts->ts_gru) {
STAT(load_user_context);
- if (!gru_assign_gru_context(gts, blade_id)) {
+ if (!gru_assign_gru_context(gts)) {
preempt_enable();
mutex_unlock(&gts->ts_ctxlock);
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(GRU_ASSIGN_DELAY); /* true hack ZZZ */
- blade_id = uv_numa_blade_id();
if (gts->ts_steal_jiffies + GRU_STEAL_DELAY < jiffies)
- gru_steal_context(gts, blade_id);
+ gru_steal_context(gts);
goto again;
}
gru_load_context(gts);