freedreno: make fd_batch a one-shot thing

Re-allocate rather than re-use.  Originally we had an unnecessarily
complex design to avoid re-allocating cmdstream buffers.  But now that
support for "growable" cmdstream buffers has been in place for a couple
years, I guess we can care a bit less about the extra overhead on older
kernels.

But making the batches one-shot removes a class of potential race
conditions vs the flush_queue.

Signed-off-by: Rob Clark <robdclark@gmail.com>

diff --git a/src/gallium/drivers/freedreno/freedreno_batch.c b/src/gallium/drivers/freedreno/freedreno_batch.c
index b6f030ac90385d6052615be2e7fd8bb470773d74..18e4ca5fb03bff747ed7770a981247239a26d269 100644 (file)
--- a/src/gallium/drivers/freedreno/freedreno_batch.c
+++ b/src/gallium/drivers/freedreno/freedreno_batch.c
@@ -72,6 +72,7 @@ batch_init(struct fd_batch *batch)
        batch->cleared = batch->partial_cleared = 0;
        batch->restore = batch->resolve = 0;
        batch->needs_flush = false;
+       batch->flushed = false;
        batch->gmem_reason = 0;
        batch->num_draws = 0;
        batch->stage = FD_STAGE_NULL;
@@ -117,6 +118,8 @@ fd_batch_create(struct fd_context *ctx, bool nondraw)
 static void
 batch_fini(struct fd_batch *batch)
 {
+       DBG("%p", batch);
+
        pipe_resource_reference(&batch->query_buf, NULL);
 
        if (batch->in_fence_fd != -1)
@@ -259,6 +262,8 @@ batch_flush_func(void *job, int id)
 {
        struct fd_batch *batch = job;
 
+       DBG("%p", batch);
+
        fd_gmem_render_tiles(batch);
        batch_reset_resources(batch);
 }
@@ -275,9 +280,8 @@ batch_flush(struct fd_batch *batch, bool force)
 {
        DBG("%p: needs_flush=%d", batch, batch->needs_flush);
 
-       if (!batch->needs_flush) {
+       if (batch->flushed)
                return;
-       }
 
        batch->needs_flush = false;
 
@@ -289,6 +293,8 @@ batch_flush(struct fd_batch *batch, bool force)
        fd_context_all_dirty(batch->ctx);
        batch_flush_reset_dependencies(batch, true);
 
+       batch->flushed = true;
+
        if (batch->ctx->screen->reorder) {
                struct fd_batch *tmp = NULL;
                fd_batch_reference(&tmp, batch);
@@ -306,13 +312,9 @@ batch_flush(struct fd_batch *batch, bool force)
 
        debug_assert(batch->reference.count > 0);
 
-       if (batch == batch->ctx->batch) {
-               batch_reset(batch);
-       } else {
-               mtx_lock(&batch->ctx->screen->lock);
-               fd_bc_invalidate_batch(batch, false);
-               mtx_unlock(&batch->ctx->screen->lock);
-       }
+       mtx_lock(&batch->ctx->screen->lock);
+       fd_bc_invalidate_batch(batch, false);
+       mtx_unlock(&batch->ctx->screen->lock);
 }
 
 /* NOTE: could drop the last ref to batch
@@ -326,16 +328,36 @@ batch_flush(struct fd_batch *batch, bool force)
 void
 fd_batch_flush(struct fd_batch *batch, bool sync, bool force)
 {
+       struct fd_batch *tmp = NULL;
+       bool newbatch = false;
+
        /* NOTE: we need to hold an extra ref across the body of flush,
         * since the last ref to this batch could be dropped when cleaning
         * up used_resources
         */
-       struct fd_batch *tmp = NULL;
-
        fd_batch_reference(&tmp, batch);
+
+       if (batch == batch->ctx->batch) {
+               batch->ctx->batch = NULL;
+               newbatch = true;
+       }
+
        batch_flush(tmp, force);
+
+       if (newbatch) {
+               struct fd_context *ctx = batch->ctx;
+               struct fd_batch *new_batch =
+                       fd_batch_from_fb(&ctx->screen->batch_cache, ctx, &batch->framebuffer);
+
+               util_copy_framebuffer_state(&new_batch->framebuffer, &batch->framebuffer);
+
+               fd_batch_reference(&batch, NULL);
+               ctx->batch = new_batch;
+       }
+
        if (sync)
                fd_batch_sync(tmp);
+
        fd_batch_reference(&tmp, NULL);
 }
 
@@ -447,6 +469,8 @@ fd_batch_resource_used(struct fd_batch *batch, struct fd_resource *rsc, bool wri
 void
 fd_batch_check_size(struct fd_batch *batch)
 {
+       debug_assert(!batch->flushed);
+
        if (fd_device_version(batch->ctx->screen->dev) >= FD_VERSION_UNLIMITED_CMDS)
                return;
 

diff --git a/src/gallium/drivers/freedreno/freedreno_batch.h b/src/gallium/drivers/freedreno/freedreno_batch.h
index b113c0713604a254963aa0c25d63ada3089d3110..294eca8f53198e00e8eeaa5adcdc735359f05fdf 100644 (file)
--- a/src/gallium/drivers/freedreno/freedreno_batch.h
+++ b/src/gallium/drivers/freedreno/freedreno_batch.h
@@ -96,6 +96,7 @@ struct fd_batch {
        /* is this a non-draw batch (ie compute/blit which has no pfb state)? */
        bool nondraw : 1;
        bool needs_flush : 1;
+       bool flushed : 1;
        bool blit : 1;
        bool back_blit : 1;      /* only blit so far is resource shadowing back-blit */