gpu: nvgpu: Fix OOM case for buddy allocator

The allocator could attempt to use a buddy list for an order larger than
the max order when all the valid buddy lists were empty. This patch
ensures that when looking for a particular order buddy that the passed
order is valid.

Also handle the prints in the no-mem case a litle differently. Only print
and update alloc info when there was a successful allocation.

Lastly print hex numbers for the allocator stats printing function.

Change-Id: If289f3e8925e236e3b7d84206a75bd45a14082a1
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: http://git-master/r/745071
(cherry picked from commit f3548e67f435975238b55ac152871dcd60a1a907)
Reviewed-on: http://git-master/r/753280
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 22 insertions, 13 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_allocator.c b/drivers/gpu/nvgpu/gk20a/gk20a_allocator.c
index 56fb22df..badfcd9f 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a_allocator.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a_allocator.c
@@ -573,7 +573,8 @@ static struct gk20a_buddy *__balloc_find_buddy(struct gk20a_allocator *a,
 {
         struct gk20a_buddy *bud;
 
-        if (list_empty(balloc_get_order_list(a, order)))
+        if (order > a->max_order ||
+            list_empty(balloc_get_order_list(a, order)))
                 return NULL;
 
         if (a->flags & GPU_BALLOC_GVA_SPACE &&
@@ -609,6 +610,10 @@ static u64 __balloc_do_alloc(struct gk20a_allocator *a, u64 order, int pte_size)
         while (!(bud = __balloc_find_buddy(a, split_order, pte_size)))
                 split_order++;
 
+        /* Out of memory! */
+        if (!bud)
+                return 0;
+
         while (bud->order != order) {
                 if (balloc_split_buddy(a, bud, pte_size))
                         return 0; /* No mem... */
@@ -658,15 +663,19 @@ u64 gk20a_balloc(struct gk20a_allocator *a, u64 len)
 
         addr = __balloc_do_alloc(a, order, pte_size);
 
-        a->bytes_alloced += len;
-        a->bytes_alloced_real += balloc_order_to_len(a, order);
+        if (addr) {
+                a->bytes_alloced += len;
+                a->bytes_alloced_real += balloc_order_to_len(a, order);
+                balloc_dbg(a, "Alloc 0x%-10llx %3lld:0x%-10llx pte_size=%s\n",
+                           addr, order, len,
+                           pte_size == gmmu_page_size_big   ? "big" :
+                           pte_size == gmmu_page_size_small ? "small" :
+                           "NA/any");
+        } else {
+                balloc_dbg(a, "Alloc failed: no mem!\n");
+        }
 
         balloc_unlock(a);
-        balloc_dbg(a, "Alloc 0x%-10llx %3lld:0x%-10llx pte_size=%s\n",
-                   addr, order, len,
-                   pte_size == gmmu_page_size_big   ? "big" :
-                   pte_size == gmmu_page_size_small ? "small" :
-                   "NA/any");
 
         balloc_trace_func_done();
         return addr;
@@ -1071,11 +1080,11 @@ static void balloc_print_stats(struct gk20a_allocator *a, struct seq_file *s,
         __balloc_pstat(s, "base = %llu, limit = %llu, blk_size = %llu\n",
                    a->base, a->length, a->blk_size);
         __balloc_pstat(s, "Internal params:\n");
-        __balloc_pstat(s, "  start = %llu\n", a->start);
-        __balloc_pstat(s, "  end   = %llu\n", a->end);
-        __balloc_pstat(s, "  count = %llu\n", a->count);
-        __balloc_pstat(s, "  blks  = %llu\n", a->blks);
-        __balloc_pstat(s, "  max_order  = %llu\n", a->max_order);
+        __balloc_pstat(s, "  start = 0x%llx\n", a->start);
+        __balloc_pstat(s, "  end   = 0x%llx\n", a->end);
+        __balloc_pstat(s, "  count = 0x%llx\n", a->count);
+        __balloc_pstat(s, "  blks  = 0x%llx\n", a->blks);
+        __balloc_pstat(s, "  max_order = %llu\n", a->max_order);
 
         __balloc_pstat(s, "Buddy blocks:\n");
         __balloc_pstat(s, "  Order   Free    Alloced   Split\n");