gru: bug fixes for GRU exception handling

[pandora-kernel.git] / drivers / misc / sgi-gru / grufault.c

diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c
index ab11855..4089f86 100644 (file)
--- a/drivers/misc/sgi-gru/grufault.c
+++ b/drivers/misc/sgi-gru/grufault.c
@@ -334,6 +334,8 @@ static int gru_try_dropin(struct gru_thread_state *gts,
         * Might be a hardware race OR a stupid user. Ignore FMM because FMM
         * is a transient state.
         */
+       if (tfh->status != TFHSTATUS_EXCEPTION)
+               goto failnoexception;
        if (tfh->state == TFHSTATE_IDLE)
                goto failidle;
        if (tfh->state == TFHSTATE_MISS_FMM && cb)
@@ -401,8 +403,17 @@ failfmm:
        gru_dbg(grudev, "FAILED fmm tfh: 0x%p, state %d\n", tfh, tfh->state);
        return 0;
 
+failnoexception:
+       /* TFH status did not show exception pending */
+       gru_flush_cache(tfh);
+       if (cb)
+               gru_flush_cache(cb);
+       STAT(tlb_dropin_fail_no_exception);
+       gru_dbg(grudev, "FAILED non-exception tfh: 0x%p, status %d, state %d\n", tfh, tfh->status, tfh->state);
+       return 0;
+
 failidle:
-       /* TFH was idle  - no miss pending */
+       /* TFH state was idle  - no miss pending */
        gru_flush_cache(tfh);
        if (cb)
                gru_flush_cache(cb);
@@ -472,7 +483,8 @@ irqreturn_t gru_intr(int irq, void *dev_id)
                 * This is running in interrupt context. Trylock the mmap_sem.
                 * If it fails, retry the fault in user context.
                 */
-               if (down_read_trylock(&gts->ts_mm->mmap_sem)) {
+               if (!gts->ts_force_cch_reload &&
+                                       down_read_trylock(&gts->ts_mm->mmap_sem)) {
                        gru_try_dropin(gts, tfh, NULL);
                        up_read(&gts->ts_mm->mmap_sem);
                } else {
@@ -595,14 +607,19 @@ int gru_get_exception_detail(unsigned long arg)
                excdet.ecause = cbe->ecause;
                excdet.exceptdet0 = cbe->idef1upd;
                excdet.exceptdet1 = cbe->idef3upd;
+               excdet.cbrstate = cbe->cbrstate;
+               excdet.cbrexecstatus = cbe->cbrexecstatus;
                ret = 0;
        } else {
                ret = -EAGAIN;
        }
        gru_unlock_gts(gts);
 
-       gru_dbg(grudev, "address 0x%lx, ecause 0x%x\n", excdet.cb,
-               excdet.ecause);
+       gru_dbg(grudev,
+               "cb 0x%lx, op %d, exopc %d, cbrstate %d, cbrexecstatus 0x%x, ecause 0x%x, "
+               "exdet0 0x%lx, exdet1 0x%x\n",
+               excdet.cb, excdet.opc, excdet.exopc, excdet.cbrstate, excdet.cbrexecstatus,
+               excdet.ecause, excdet.exceptdet0, excdet.exceptdet1);
        if (!ret && copy_to_user((void __user *)arg, &excdet, sizeof(excdet)))
                ret = -EFAULT;
        return ret;