freedreno: add madvise support

With a new enough drm/msm, we can let the kernel know about buffers that
are in the bo cache, so the kernel can free them under memory pressure.

Signed-off-by: Rob Clark <robclark@freedesktop.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/freedreno/msm/msm_bo.c b/freedreno/msm/msm_bo.c
index cd05a6cd..cfaec827 100644
--- a/freedreno/msm/msm_bo.c
+++ b/freedreno/msm/msm_bo.c
@@ -89,6 +89,25 @@ static void msm_bo_cpu_fini(struct fd_bo *bo)
         drmCommandWrite(bo->dev->fd, DRM_MSM_GEM_CPU_FINI, &req, sizeof(req));
 }
 
+static int msm_bo_madvise(struct fd_bo *bo, int willneed)
+{
+        struct drm_msm_gem_madvise req = {
+                        .handle = bo->handle,
+                        .madv = willneed ? MSM_MADV_WILLNEED : MSM_MADV_DONTNEED,
+        };
+        int ret;
+
+        /* older kernels do not support this: */
+        if (bo->dev->version < 1)
+                return willneed;
+
+        ret = drmCommandWriteRead(bo->dev->fd, DRM_MSM_GEM_MADVISE, &req, sizeof(req));
+        if (ret)
+                return ret;
+
+        return req.retained;
+}
+
 static void msm_bo_destroy(struct fd_bo *bo)
 {
         struct msm_bo *msm_bo = to_msm_bo(bo);
@@ -100,6 +119,7 @@ static const struct fd_bo_funcs funcs = {
                 .offset = msm_bo_offset,
                 .cpu_prep = msm_bo_cpu_prep,
                 .cpu_fini = msm_bo_cpu_fini,
+                .madvise = msm_bo_madvise,
                 .destroy = msm_bo_destroy,
 };