gru: allow users to specify gru chiplet 3

This patch builds on the infrastructure introduced in the patches that
allow user specification of GRU blades & chiplets for context allocation.

This patch simplifies the algorithms for migrating GRU contexts between
blades.

No new functionality is introduced.

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>

3 files changed, 13 insertions, 29 deletions

diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c
index 321ad809f345..9470303a9cb9 100644
--- a/drivers/misc/sgi-gru/grufault.c
+++ b/drivers/misc/sgi-gru/grufault.c
@@ -362,7 +362,7 @@ static int gru_try_dropin(struct gru_thread_state *gts,
 
         if (!(gts->ts_sizeavail & GRU_SIZEAVAIL(pageshift))) {
                 gts->ts_sizeavail |= GRU_SIZEAVAIL(pageshift);
-                if (atomic || !gru_update_cch(gts, 0)) {
+                if (atomic || !gru_update_cch(gts)) {
                         gts->ts_force_cch_reload = 1;
                         goto failupm;
                 }
@@ -553,14 +553,12 @@ int gru_handle_user_call_os(unsigned long cb)
          */
         if (gts->ts_gru && gts->ts_force_cch_reload) {
                 gts->ts_force_cch_reload = 0;
-                gru_update_cch(gts, 0);
+                gru_update_cch(gts);
         }
 
         ret = -EAGAIN;
         cbrnum = thread_cbr_number(gts, ucbnum);
-        if (gts->ts_force_unload) {
-                gru_unload_context(gts, 1);
-        } else if (gts->ts_gru) {
+        if (gts->ts_gru) {
                 tfh = get_tfh_by_index(gts->ts_gru, cbrnum);
                 cbk = get_gseg_base_address_cb(gts->ts_gru->gs_gru_base_vaddr,
                                 gts->ts_ctxnum, ucbnum);
diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index 54ad7544a9a0..9ec54bde4472 100644
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -551,7 +551,6 @@ void gru_unload_context(struct gru_thread_state *gts, int savestate)
 
         if (cch_deallocate(cch))
                 BUG();
-        gts->ts_force_unload = 0;       /* ts_force_unload locked by CCH lock */
         unlock_cch_handle(cch);
 
         gru_free_gru_context(gts);
@@ -624,11 +623,8 @@ void gru_load_context(struct gru_thread_state *gts)
  * Update fields in an active CCH:
  *      - retarget interrupts on local blade
  *      - update sizeavail mask
- *      - force a delayed context unload by clearing the CCH asids. This
- *        forces TLB misses for new GRU instructions. The context is unloaded
- *        when the next TLB miss occurs.
  */
-int gru_update_cch(struct gru_thread_state *gts, int force_unload)
+int gru_update_cch(struct gru_thread_state *gts)
 {
         struct gru_context_configuration_handle *cch;
         struct gru_state *gru = gts->ts_gru;
@@ -642,21 +638,13 @@ int gru_update_cch(struct gru_thread_state *gts, int force_unload)
                         goto exit;
                 if (cch_interrupt(cch))
                         BUG();
-                if (!force_unload) {
-                        for (i = 0; i < 8; i++)
-                                cch->sizeavail[i] = gts->ts_sizeavail;
-                        gts->ts_tlb_int_select = gru_cpu_fault_map_id();
-                        cch->tlb_int_select = gru_cpu_fault_map_id();
-                        cch->tfm_fault_bit_enable =
-                          (gts->ts_user_options == GRU_OPT_MISS_FMM_POLL
-                            || gts->ts_user_options == GRU_OPT_MISS_FMM_INTR);
-                } else {
-                        for (i = 0; i < 8; i++)
-                                cch->asid[i] = 0;
-                        cch->tfm_fault_bit_enable = 0;
-                        cch->tlb_int_enable = 0;
-                        gts->ts_force_unload = 1;
-                }
+                for (i = 0; i < 8; i++)
+                        cch->sizeavail[i] = gts->ts_sizeavail;
+                gts->ts_tlb_int_select = gru_cpu_fault_map_id();
+                cch->tlb_int_select = gru_cpu_fault_map_id();
+                cch->tfm_fault_bit_enable =
+                  (gts->ts_user_options == GRU_OPT_MISS_FMM_POLL
+                    || gts->ts_user_options == GRU_OPT_MISS_FMM_INTR);
                 if (cch_start(cch))
                         BUG();
                 ret = 1;
@@ -681,7 +669,7 @@ static int gru_retarget_intr(struct gru_thread_state *gts)
 
         gru_dbg(grudev, "retarget from %d to %d\n", gts->ts_tlb_int_select,
                 gru_cpu_fault_map_id());
-        return gru_update_cch(gts, 0);
+        return gru_update_cch(gts);
 }
 
 /*
diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h
index 8a61a8599bac..676da7821992 100644
--- a/drivers/misc/sgi-gru/grutables.h
+++ b/drivers/misc/sgi-gru/grutables.h
@@ -382,8 +382,6 @@ struct gru_thread_state {
         char                    ts_blade;       /* If >= 0, migrate context if
                                                    ref from diferent blade */
         char                    ts_force_cch_reload;
-        char                    ts_force_unload;/* force context to be unloaded
-                                                   after migration */
         char                    ts_cbr_idx[GRU_CBR_AU];/* CBR numbers of each
                                                           allocated CB */
         int                     ts_data_valid;  /* Indicates if ts_gdata has
@@ -636,7 +634,7 @@ extern struct gru_state *gru_assign_gru_context(struct gru_thread_state *gts);
 extern void gru_load_context(struct gru_thread_state *gts);
 extern void gru_steal_context(struct gru_thread_state *gts);
 extern void gru_unload_context(struct gru_thread_state *gts, int savestate);
-extern int gru_update_cch(struct gru_thread_state *gts, int force_unload);
+extern int gru_update_cch(struct gru_thread_state *gts);
 extern void gts_drop(struct gru_thread_state *gts);
 extern void gru_tgh_flush_init(struct gru_state *gru);
 extern int gru_kservices_init(void);