The patch below does not apply to the 3.17-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From e300180f71037fd9ed1ca967006fd9f3ee466bcd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <[email protected]>
Date: Thu, 9 Oct 2014 15:02:59 +0900
Subject: [PATCH] drm/ttm: Don't evict BOs outside of the requested placement
 range
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The radeon driver uses placement range restrictions for several reasons,
in particular to make sure BOs in VRAM can be accessed by the CPU, e.g.
during a page fault.

Without this change, TTM could evict other BOs while trying to satisfy
the requested placement, even if the evicted BOs were outside of the
requested placement range. Doing so didn't free up any space in the
requested placement range, so the (potentially high) eviction cost was
incurred for no benefit.

Nominating for stable because radeon driver changes in 3.17 made this
much more noticeable than before.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=84662
Cc: [email protected]
Signed-off-by: Michel Dänzer <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index ba74a11bceb7..d395b0bef73b 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -709,6 +709,7 @@ out:
 
 static int ttm_mem_evict_first(struct ttm_bo_device *bdev,
                                uint32_t mem_type,
+                               const struct ttm_place *place,
                                bool interruptible,
                                bool no_wait_gpu)
 {
@@ -720,8 +721,21 @@ static int ttm_mem_evict_first(struct ttm_bo_device *bdev,
        spin_lock(&glob->lru_lock);
        list_for_each_entry(bo, &man->lru, lru) {
                ret = __ttm_bo_reserve(bo, false, true, false, NULL);
-               if (!ret)
+               if (!ret) {
+                       if (place && (place->fpfn || place->lpfn)) {
+                               /* Don't evict this BO if it's outside of the
+                                * requested placement range
+                                */
+                               if (place->fpfn >= (bo->mem.start + 
bo->mem.size) ||
+                                   (place->lpfn && place->lpfn <= 
bo->mem.start)) {
+                                       __ttm_bo_unreserve(bo);
+                                       ret = -EBUSY;
+                                       continue;
+                               }
+                       }
+
                        break;
+               }
        }
 
        if (ret) {
@@ -782,7 +796,7 @@ static int ttm_bo_mem_force_space(struct ttm_buffer_object 
*bo,
                        return ret;
                if (mem->mm_node)
                        break;
-               ret = ttm_mem_evict_first(bdev, mem_type,
+               ret = ttm_mem_evict_first(bdev, mem_type, place,
                                          interruptible, no_wait_gpu);
                if (unlikely(ret != 0))
                        return ret;
@@ -1233,7 +1247,7 @@ static int ttm_bo_force_list_clean(struct ttm_bo_device 
*bdev,
        spin_lock(&glob->lru_lock);
        while (!list_empty(&man->lru)) {
                spin_unlock(&glob->lru_lock);
-               ret = ttm_mem_evict_first(bdev, mem_type, false, false);
+               ret = ttm_mem_evict_first(bdev, mem_type, NULL, false, false);
                if (ret) {
                        if (allow_errors) {
                                return ret;

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