Commit c1fdc2f0 authored by Brad Volkin's avatar Brad Volkin Committed by Daniel Vetter

tests/gem_exec_parse: fix batch_len setting for cmd-crossing-page

The size of the batch buffer passed to the kernel is significantly
larger than the size of the batch buffer passed to the function. A
proposed optimization as part of the batch copy kernel series is to
use batch_len for the copy and parse operations, which leads to a
false "batch without MI_BATCH_BUFFER_END" failure for this test.

To fix this, modify the test to set batch_start_offset and batch_len
such that they define the range of actual commands in the batch,
including a few of the surrounding nops for alignment purposes.

v2: update batch_start_offset as well
Signed-off-by: default avatarBrad Volkin <>
Signed-off-by: Daniel Vetter's avatarDaniel Vetter <>
parent 4dd6e0ed
......@@ -144,16 +144,18 @@ static void exec_split_batch(int fd, uint32_t *cmds,
struct drm_i915_gem_exec_object2 objs[1];
uint32_t cmd_bo;
uint32_t noop[1024] = { 0 };
const int alloc_size = 4096 * 2;
const int actual_start_offset = 4096-sizeof(uint32_t);
// Allocate and fill a 2-page batch with noops
cmd_bo = gem_create(fd, 4096 * 2);
cmd_bo = gem_create(fd, alloc_size);
gem_write(fd, cmd_bo, 0, noop, sizeof(noop));
gem_write(fd, cmd_bo, 4096, noop, sizeof(noop));
// Write the provided commands such that the first dword
// of the command buffer is the last dword of the first
// page (i.e. the command is split across the two pages).
gem_write(fd, cmd_bo, 4096-sizeof(uint32_t), cmds, size);
gem_write(fd, cmd_bo, actual_start_offset, cmds, size);
objs[0].handle = cmd_bo;
objs[0].relocation_count = 0;
......@@ -166,8 +168,14 @@ static void exec_split_batch(int fd, uint32_t *cmds,
execbuf.buffers_ptr = (uintptr_t)objs;
execbuf.buffer_count = 1;
execbuf.batch_start_offset = 0;
execbuf.batch_len = size;
// NB: We want batch_start_offset and batch_len to point to the block
// of the actual commands (i.e. at the last dword of the first page),
// but have to adjust both the start offset and length to meet the
// kernel driver's requirements on the alignment of those fields.
execbuf.batch_start_offset = actual_start_offset & ~0x7;
execbuf.batch_len =
ALIGN(size + actual_start_offset - execbuf.batch_start_offset,
execbuf.cliprects_ptr = 0;
execbuf.num_cliprects = 0;
execbuf.DR1 = 0;
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