sgi-gru: aSID (context management) bug fixes

This patch fixes bugs related to ASID (context id) management in the GRU
driver.  These changes are all internal to the SGI GRU driver and have no
effect on the base kernel.

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>

diff --git a/drivers/misc/sgi-gru/grufile.c b/drivers/misc/sgi-gru/grufile.c
index 812678d8b47d92d4b8ca92e2e858001d397b9350..f8dcdb1a0ec4733c678df1b07623d248e9336905 100644 (file)
--- a/drivers/misc/sgi-gru/grufile.c
+++ b/drivers/misc/sgi-gru/grufile.c
@@ -274,6 +274,7 @@ static void gru_init_chiplet(struct gru_state *gru, unsigned long paddr,
        gru->gs_blade_id = bid;
        gru->gs_cbr_map = (GRU_CBR_AU == 64) ? ~0 : (1UL << GRU_CBR_AU) - 1;
        gru->gs_dsr_map = (1UL << GRU_DSR_AU) - 1;
+       gru->gs_asid_limit = MAX_ASID;
        gru_tgh_flush_init(gru);
        gru_dbg(grudev, "bid %d, nid %d, gid %d, vaddr %p (0x%lx)\n",
                bid, nid, gru->gs_gid, gru->gs_gru_base_vaddr,

diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index de60458f6d1e2d40c84d0db46e1a4e7f36838702..5fc7b5ecde66cf2696fc5e6728eb1b63e152fc24 100644 (file)
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -79,7 +79,6 @@ static int gru_wrap_asid(struct gru_state *gru)
        gru_dbg(grudev, "gid %d\n", gru->gs_gid);
        STAT(asid_wrap);
        gru->gs_asid_gen++;
-       gru_flush_all_tlb(gru);
        return MIN_ASID;
 }
 
@@ -93,6 +92,7 @@ static int gru_reset_asid_limit(struct gru_state *gru, int asid)
        limit = MAX_ASID;
        if (asid >= limit)
                asid = gru_wrap_asid(gru);
+       gru_flush_all_tlb(gru);
        gid = gru->gs_gid;
 again:
        for (i = 0; i < GRU_NUM_CCH; i++) {
@@ -131,12 +131,10 @@ static int gru_assign_asid(struct gru_state *gru)
 {
        int asid;
 
-       spin_lock(&gru->gs_asid_lock);
        gru->gs_asid += ASID_INC;
        asid = gru->gs_asid;
        if (asid >= gru->gs_asid_limit)
                asid = gru_reset_asid_limit(gru, asid);
-       spin_unlock(&gru->gs_asid_lock);
 
        gru_dbg(grudev, "gid %d, asid 0x%x\n", gru->gs_gid, asid);
        return asid;
@@ -227,7 +225,9 @@ static int gru_load_mm_tracker(struct gru_state *gru,
        spin_lock(&gms->ms_asid_lock);
        asid = asids->mt_asid;
 
-       if (asid == 0 || asids->mt_asid_gen != gru->gs_asid_gen) {
+       spin_lock(&gru->gs_asid_lock);
+       if (asid == 0 || (asids->mt_ctxbitmap == 0 && asids->mt_asid_gen !=
+                         gru->gs_asid_gen)) {
                asid = gru_assign_asid(gru);
                asids->mt_asid = asid;
                asids->mt_asid_gen = gru->gs_asid_gen;
@@ -235,6 +235,7 @@ static int gru_load_mm_tracker(struct gru_state *gru,
        } else {
                STAT(asid_reuse);
        }
+       spin_unlock(&gru->gs_asid_lock);
 
        BUG_ON(asids->mt_ctxbitmap & ctxbitmap);
        asids->mt_ctxbitmap |= ctxbitmap;
@@ -259,10 +260,12 @@ static void gru_unload_mm_tracker(struct gru_state *gru,
        asids = &gms->ms_asids[gru->gs_gid];
        ctxbitmap = (1 << gts->ts_ctxnum);
        spin_lock(&gms->ms_asid_lock);
+       spin_lock(&gru->gs_asid_lock);
        BUG_ON((asids->mt_ctxbitmap & ctxbitmap) != ctxbitmap);
        asids->mt_ctxbitmap ^= ctxbitmap;
        gru_dbg(grudev, "gid %d, gts %p, gms %p, ctxnum 0x%d, asidmap 0x%lx\n",
                gru->gs_gid, gts, gms, gts->ts_ctxnum, gms->ms_asidmap[0]);
+       spin_unlock(&gru->gs_asid_lock);
        spin_unlock(&gms->ms_asid_lock);
 }
 
@@ -412,6 +415,7 @@ static void gru_free_gru_context(struct gru_thread_state *gts)
        __clear_bit(gts->ts_ctxnum, &gru->gs_context_map);
        gts->ts_ctxnum = NULLCTX;
        gts->ts_gru = NULL;
+       gts->ts_blade = -1;
        spin_unlock(&gru->gs_lock);
 
        gts_drop(gts);
@@ -731,6 +735,7 @@ 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);