[PATCH 3/3] drm/amdgpu: Initialize the variables in a straight-forward way

[Alex Deucher]

From: Alex Xie <alexbin....@amd.com>

Initialize the variable in a straight-forward way instead of
hiding the initialization inside the loop. This can also
reduce one function call.

Signed-off-by: Alex Xie <AlexBin.Xie at amd.com>
Reviewed-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 0c17348..311a7c3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -762,15 +762,36 @@ static void amdgpu_vm_update_ptes(struct amdgpu_device 
*adev,
 {
        const uint64_t mask = AMDGPU_VM_PTE_COUNT - 1;

-       uint64_t cur_pe_start = ~0, cur_pe_end = ~0, cur_dst = ~0;
+       uint64_t cur_pe_start, cur_pe_end, cur_dst;
        uint64_t addr; /* next GPU address to be updated */
+       uint64_t pt_idx;
+       struct amdgpu_bo *pt;
+       unsigned nptes; /* next number of ptes to be updated */
+       uint64_t next_pe_start;
+
+       /* initialize the variables */
+       addr = start;
+       pt_idx = addr >> amdgpu_vm_block_size;
+       pt = vm->page_tables[pt_idx].entry.robj;
+
+       if ((addr & ~mask) == (end & ~mask))
+               nptes = end - addr;
+       else
+               nptes = AMDGPU_VM_PTE_COUNT - (addr & mask);
+
+       cur_pe_start = amdgpu_bo_gpu_offset(pt);
+       cur_pe_start += (addr & mask) * 8;
+       cur_pe_end = cur_pe_start + 8 * nptes;
+       cur_dst = dst;
+
+       /* for next ptb*/
+       addr += nptes;
+       dst += nptes * AMDGPU_GPU_PAGE_SIZE;

        /* walk over the address space and update the page tables */
-       for (addr = start; addr < end; ) {
-               uint64_t pt_idx = addr >> amdgpu_vm_block_size;
-               struct amdgpu_bo *pt = vm->page_tables[pt_idx].entry.robj;
-               unsigned nptes; /* next number of ptes to be updated */
-               uint64_t next_pe_start;
+       while (addr < end) {
+               pt_idx = addr >> amdgpu_vm_block_size;
+               pt = vm->page_tables[pt_idx].entry.robj;

                if ((addr & ~mask) == (end & ~mask))
                        nptes = end - addr;
@@ -796,6 +817,7 @@ static void amdgpu_vm_update_ptes(struct amdgpu_device 
*adev,
                        cur_dst = dst;
                }

+               /* for next ptb*/
                addr += nptes;
                dst += nptes * AMDGPU_GPU_PAGE_SIZE;
        }
-- 
2.5.5