1 files changed, 660 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/channel.c b/drivers/gpu/nvgpu/common/linux/channel.c
new file mode 100644
index 00000000..40b11b86
--- /dev/null
+++ b/drivers/gpu/nvgpu/common/linux/channel.c
@@ -0,0 +1,660 @@
+/*
+ * Copyright (c) 2017, NVIDIA Corporation.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <nvgpu/enabled.h>
+#include <nvgpu/debug.h>
+#include <nvgpu/ltc.h>
+
+/*
+ * This is required for nvgpu_vm_find_buf() which is used in the tracing
+ * code. Once we can get and access userspace buffers without requiring
+ * direct dma_buf usage this can be removed.
+ */
+#include <nvgpu/linux/vm.h>
+
+#include "gk20a/gk20a.h"
+
+#include <nvgpu/hw/gk20a/hw_pbdma_gk20a.h>
+
+#include <linux/uaccess.h>
+#include <linux/dma-buf.h>
+#include <trace/events/gk20a.h>
+#include <uapi/linux/nvgpu.h>
+
+u32 nvgpu_get_gpfifo_entry_size(void)
+{
+        return sizeof(struct nvgpu_gpfifo);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void trace_write_pushbuffer(struct channel_gk20a *c,
+                                   struct nvgpu_gpfifo *g)
+{
+        void *mem = NULL;
+        unsigned int words;
+        u64 offset;
+        struct dma_buf *dmabuf = NULL;
+
+        if (gk20a_debug_trace_cmdbuf) {
+                u64 gpu_va = (u64)g->entry0 |
+                        (u64)((u64)pbdma_gp_entry1_get_hi_v(g->entry1) << 32);
+                int err;
+
+                words = pbdma_gp_entry1_length_v(g->entry1);
+                err = nvgpu_vm_find_buf(c->vm, gpu_va, &dmabuf, &offset);
+                if (!err)
+                        mem = dma_buf_vmap(dmabuf);
+        }
+
+        if (mem) {
+                u32 i;
+                /*
+                 * Write in batches of 128 as there seems to be a limit
+                 * of how much you can output to ftrace at once.
+                 */
+                for (i = 0; i < words; i += 128U) {
+                        trace_gk20a_push_cmdbuf(
+                                c->g->name,
+                                0,
+                                min(words - i, 128U),
+                                offset + i * sizeof(u32),
+                                mem);
+                }
+                dma_buf_vunmap(dmabuf, mem);
+        }
+}
+#endif
+
+static void trace_write_pushbuffer_range(struct channel_gk20a *c,
+                                         struct nvgpu_gpfifo *g,
+                                         struct nvgpu_gpfifo __user *user_gpfifo,
+                                         int offset,
+                                         int count)
+{
+#ifdef CONFIG_DEBUG_FS
+        u32 size;
+        int i;
+        struct nvgpu_gpfifo *gp;
+        bool gpfifo_allocated = false;
+
+        if (!gk20a_debug_trace_cmdbuf)
+                return;
+
+        if (!g && !user_gpfifo)
+                return;
+
+        if (!g) {
+                size = count * sizeof(struct nvgpu_gpfifo);
+                if (size) {
+                        g = nvgpu_big_malloc(c->g, size);
+                        if (!g)
+                                return;
+
+                        if (copy_from_user(g, user_gpfifo, size)) {
+                                nvgpu_big_free(c->g, g);
+                                return;
+                        }
+                }
+                gpfifo_allocated = true;
+        }
+
+        gp = g + offset;
+        for (i = 0; i < count; i++, gp++)
+                trace_write_pushbuffer(c, gp);
+
+        if (gpfifo_allocated)
+                nvgpu_big_free(c->g, g);
+#endif
+}
+
+/*
+ * Handle the submit synchronization - pre-fences and post-fences.
+ */
+static int gk20a_submit_prepare_syncs(struct channel_gk20a *c,
+                                      struct nvgpu_fence *fence,
+                                      struct channel_gk20a_job *job,
+                                      struct priv_cmd_entry **wait_cmd,
+                                      struct priv_cmd_entry **incr_cmd,
+                                      struct gk20a_fence **pre_fence,
+                                      struct gk20a_fence **post_fence,
+                                      bool force_need_sync_fence,
+                                      bool register_irq,
+                                      u32 flags)
+{
+        struct gk20a *g = c->g;
+        bool need_sync_fence = false;
+        bool new_sync_created = false;
+        int wait_fence_fd = -1;
+        int err = 0;
+        bool need_wfi = !(flags & NVGPU_SUBMIT_GPFIFO_FLAGS_SUPPRESS_WFI);
+        bool pre_alloc_enabled = channel_gk20a_is_prealloc_enabled(c);
+
+        /*
+         * If user wants to always allocate sync_fence_fds then respect that;
+         * otherwise, allocate sync_fence_fd based on user flags.
+         */
+        if (force_need_sync_fence)
+                need_sync_fence = true;
+
+        if (g->aggressive_sync_destroy_thresh) {
+                nvgpu_mutex_acquire(&c->sync_lock);
+                if (!c->sync) {
+                        c->sync = gk20a_channel_sync_create(c);
+                        if (!c->sync) {
+                                err = -ENOMEM;
+                                nvgpu_mutex_release(&c->sync_lock);
+                                goto fail;
+                        }
+                        new_sync_created = true;
+                }
+                nvgpu_atomic_inc(&c->sync->refcount);
+                nvgpu_mutex_release(&c->sync_lock);
+        }
+
+        if (g->ops.fifo.resetup_ramfc && new_sync_created) {
+                err = g->ops.fifo.resetup_ramfc(c);
+                if (err)
+                        goto fail;
+        }
+
+        /*
+         * Optionally insert syncpt wait in the beginning of gpfifo submission
+         * when user requested and the wait hasn't expired. Validate that the id
+         * makes sense, elide if not. The only reason this isn't being
+         * unceremoniously killed is to keep running some tests which trigger
+         * this condition.
+         */
+        if (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_WAIT) {
+                job->pre_fence = gk20a_alloc_fence(c);
+                if (!job->pre_fence) {
+                        err = -ENOMEM;
+                        goto fail;
+                }
+
+                if (!pre_alloc_enabled)
+                        job->wait_cmd = nvgpu_kzalloc(g,
+                                sizeof(struct priv_cmd_entry));
+
+                if (!job->wait_cmd) {
+                        err = -ENOMEM;
+                        goto clean_up_pre_fence;
+                }
+
+                if (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_SYNC_FENCE) {
+                        wait_fence_fd = fence->id;
+                        err = c->sync->wait_fd(c->sync, wait_fence_fd,
+                                               job->wait_cmd, job->pre_fence);
+                } else {
+                        err = c->sync->wait_syncpt(c->sync, fence->id,
+                                                   fence->value, job->wait_cmd,
+                                                   job->pre_fence);
+                }
+
+                if (!err) {
+                        if (job->wait_cmd->valid)
+                                *wait_cmd = job->wait_cmd;
+                        *pre_fence = job->pre_fence;
+                } else
+                        goto clean_up_wait_cmd;
+        }
+
+        if ((flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_GET) &&
+            (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_SYNC_FENCE))
+                need_sync_fence = true;
+
+        /*
+         * Always generate an increment at the end of a GPFIFO submission. This
+         * is used to keep track of method completion for idle railgating. The
+         * sync_pt/semaphore PB is added to the GPFIFO later on in submit.
+         */
+        job->post_fence = gk20a_alloc_fence(c);
+        if (!job->post_fence) {
+                err = -ENOMEM;
+                goto clean_up_wait_cmd;
+        }
+        if (!pre_alloc_enabled)
+                job->incr_cmd = nvgpu_kzalloc(g, sizeof(struct priv_cmd_entry));
+
+        if (!job->incr_cmd) {
+                err = -ENOMEM;
+                goto clean_up_post_fence;
+        }
+
+        if (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_GET)
+                err = c->sync->incr_user(c->sync, wait_fence_fd, job->incr_cmd,
+                                 job->post_fence, need_wfi, need_sync_fence,
+                                 register_irq);
+        else
+                err = c->sync->incr(c->sync, job->incr_cmd,
+                                    job->post_fence, need_sync_fence,
+                                    register_irq);
+        if (!err) {
+                *incr_cmd = job->incr_cmd;
+                *post_fence = job->post_fence;
+        } else
+                goto clean_up_incr_cmd;
+
+        return 0;
+
+clean_up_incr_cmd:
+        free_priv_cmdbuf(c, job->incr_cmd);
+        if (!pre_alloc_enabled)
+                job->incr_cmd = NULL;
+clean_up_post_fence:
+        gk20a_fence_put(job->post_fence);
+        job->post_fence = NULL;
+clean_up_wait_cmd:
+        free_priv_cmdbuf(c, job->wait_cmd);
+        if (!pre_alloc_enabled)
+                job->wait_cmd = NULL;
+clean_up_pre_fence:
+        gk20a_fence_put(job->pre_fence);
+        job->pre_fence = NULL;
+fail:
+        *wait_cmd = NULL;
+        *pre_fence = NULL;
+        return err;
+}
+
+static void gk20a_submit_append_priv_cmdbuf(struct channel_gk20a *c,
+                struct priv_cmd_entry *cmd)
+{
+        struct gk20a *g = c->g;
+        struct nvgpu_mem *gpfifo_mem = &c->gpfifo.mem;
+        struct nvgpu_gpfifo x = {
+                .entry0 = u64_lo32(cmd->gva),
+                .entry1 = u64_hi32(cmd->gva) |
+                        pbdma_gp_entry1_length_f(cmd->size)
+        };
+
+        nvgpu_mem_wr_n(g, gpfifo_mem, c->gpfifo.put * sizeof(x),
+                        &x, sizeof(x));
+
+        if (cmd->mem->aperture == APERTURE_SYSMEM)
+                trace_gk20a_push_cmdbuf(g->name, 0, cmd->size, 0,
+                                cmd->mem->cpu_va + cmd->off * sizeof(u32));
+
+        c->gpfifo.put = (c->gpfifo.put + 1) & (c->gpfifo.entry_num - 1);
+}
+
+/*
+ * Copy source gpfifo entries into the gpfifo ring buffer, potentially
+ * splitting into two memcpys to handle wrap-around.
+ */
+static int gk20a_submit_append_gpfifo(struct channel_gk20a *c,
+                struct nvgpu_gpfifo *kern_gpfifo,
+                struct nvgpu_gpfifo __user *user_gpfifo,
+                u32 num_entries)
+{
+        /* byte offsets */
+        u32 gpfifo_size = c->gpfifo.entry_num * sizeof(struct nvgpu_gpfifo);
+        u32 len = num_entries * sizeof(struct nvgpu_gpfifo);
+        u32 start = c->gpfifo.put * sizeof(struct nvgpu_gpfifo);
+        u32 end = start + len; /* exclusive */
+        struct nvgpu_mem *gpfifo_mem = &c->gpfifo.mem;
+        struct nvgpu_gpfifo *cpu_src;
+        int err;
+
+        if (user_gpfifo && !c->gpfifo.pipe) {
+                /*
+                 * This path (from userspace to sysmem) is special in order to
+                 * avoid two copies unnecessarily (from user to pipe, then from
+                 * pipe to gpu sysmem buffer).
+                 *
+                 * As a special case, the pipe buffer exists if PRAMIN writes
+                 * are forced, although the buffers may not be in vidmem in
+                 * that case.
+                 */
+                if (end > gpfifo_size) {
+                        /* wrap-around */
+                        int length0 = gpfifo_size - start;
+                        int length1 = len - length0;
+                        void __user *user2 = (u8 __user *)user_gpfifo + length0;
+
+                        err = copy_from_user(gpfifo_mem->cpu_va + start,
+                                        user_gpfifo, length0);
+                        if (err)
+                                return err;
+
+                        err = copy_from_user(gpfifo_mem->cpu_va,
+                                        user2, length1);
+                        if (err)
+                                return err;
+                } else {
+                        err = copy_from_user(gpfifo_mem->cpu_va + start,
+                                        user_gpfifo, len);
+                        if (err)
+                                return err;
+                }
+
+                trace_write_pushbuffer_range(c, NULL, user_gpfifo,
+                                0, num_entries);
+                goto out;
+        } else if (user_gpfifo) {
+                /* from userspace to vidmem or sysmem when pramin forced, use
+                 * the common copy path below */
+                err = copy_from_user(c->gpfifo.pipe, user_gpfifo, len);
+                if (err)
+                        return err;
+
+                cpu_src = c->gpfifo.pipe;
+        } else {
+                /* from kernel to either sysmem or vidmem, don't need
+                 * copy_from_user so use the common path below */
+                cpu_src = kern_gpfifo;
+        }
+
+        if (end > gpfifo_size) {
+                /* wrap-around */
+                int length0 = gpfifo_size - start;
+                int length1 = len - length0;
+                void *src2 = (u8 *)cpu_src + length0;
+
+                nvgpu_mem_wr_n(c->g, gpfifo_mem, start, cpu_src, length0);
+                nvgpu_mem_wr_n(c->g, gpfifo_mem, 0, src2, length1);
+        } else {
+                nvgpu_mem_wr_n(c->g, gpfifo_mem, start, cpu_src, len);
+
+        }
+
+        trace_write_pushbuffer_range(c, cpu_src, NULL, 0, num_entries);
+
+out:
+        c->gpfifo.put = (c->gpfifo.put + num_entries) &
+                (c->gpfifo.entry_num - 1);
+
+        return 0;
+}
+
+int gk20a_submit_channel_gpfifo(struct channel_gk20a *c,
+                                struct nvgpu_gpfifo *gpfifo,
+                                struct nvgpu_submit_gpfifo_args *args,
+                                u32 num_entries,
+                                u32 flags,
+                                struct nvgpu_fence *fence,
+                                struct gk20a_fence **fence_out,
+                                bool force_need_sync_fence,
+                                struct fifo_profile_gk20a *profile)
+{
+        struct gk20a *g = c->g;
+        struct priv_cmd_entry *wait_cmd = NULL;
+        struct priv_cmd_entry *incr_cmd = NULL;
+        struct gk20a_fence *pre_fence = NULL;
+        struct gk20a_fence *post_fence = NULL;
+        struct channel_gk20a_job *job = NULL;
+        /* we might need two extra gpfifo entries - one for pre fence
+         * and one for post fence. */
+        const int extra_entries = 2;
+        bool skip_buffer_refcounting = (flags &
+                        NVGPU_SUBMIT_GPFIFO_FLAGS_SKIP_BUFFER_REFCOUNTING);
+        int err = 0;
+        bool need_job_tracking;
+        bool need_deferred_cleanup = false;
+        struct nvgpu_gpfifo __user *user_gpfifo = args ?
+                (struct nvgpu_gpfifo __user *)(uintptr_t)args->gpfifo : NULL;
+
+        if (nvgpu_is_enabled(g, NVGPU_DRIVER_IS_DYING))
+                return -ENODEV;
+
+        if (c->has_timedout)
+                return -ETIMEDOUT;
+
+        if (!nvgpu_mem_is_valid(&c->gpfifo.mem))
+                return -ENOMEM;
+
+        /* fifo not large enough for request. Return error immediately.
+         * Kernel can insert gpfifo entries before and after user gpfifos.
+         * So, add extra_entries in user request. Also, HW with fifo size N
+         * can accept only N-1 entreis and so the below condition */
+        if (c->gpfifo.entry_num - 1 < num_entries + extra_entries) {
+                nvgpu_err(g, "not enough gpfifo space allocated");
+                return -ENOMEM;
+        }
+
+        if (!gpfifo && !args)
+                return -EINVAL;
+
+        if ((flags & (NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_WAIT |
+                      NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_GET)) &&
+            !fence)
+                return -EINVAL;
+
+        /* an address space needs to have been bound at this point. */
+        if (!gk20a_channel_as_bound(c)) {
+                nvgpu_err(g,
+                            "not bound to an address space at time of gpfifo"
+                            " submission.");
+                return -EINVAL;
+        }
+
+        if (profile)
+                profile->timestamp[PROFILE_ENTRY] = sched_clock();
+
+        /* update debug settings */
+        nvgpu_ltc_sync_enabled(g);
+
+        gk20a_dbg_info("channel %d", c->chid);
+
+        /*
+         * Job tracking is necessary for any of the following conditions:
+         *  - pre- or post-fence functionality
+         *  - channel wdt
+         *  - GPU rail-gating with non-deterministic channels
+         *  - buffer refcounting
+         *
+         * If none of the conditions are met, then job tracking is not
+         * required and a fast submit can be done (ie. only need to write
+         * out userspace GPFIFO entries and update GP_PUT).
+         */
+        need_job_tracking = (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_WAIT) ||
+                        (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_GET) ||
+                        c->wdt_enabled ||
+                        (g->can_railgate && !c->deterministic) ||
+                        !skip_buffer_refcounting;
+
+        if (need_job_tracking) {
+                bool need_sync_framework = false;
+
+                /*
+                 * If the channel is to have deterministic latency and
+                 * job tracking is required, the channel must have
+                 * pre-allocated resources. Otherwise, we fail the submit here
+                 */
+                if (c->deterministic && !channel_gk20a_is_prealloc_enabled(c))
+                        return -EINVAL;
+
+                need_sync_framework = force_need_sync_fence ||
+                        gk20a_channel_sync_needs_sync_framework(g) ||
+                        (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_SYNC_FENCE &&
+                        (flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_WAIT ||
+                         flags & NVGPU_SUBMIT_GPFIFO_FLAGS_FENCE_GET));
+
+                /*
+                 * Deferred clean-up is necessary for any of the following
+                 * conditions:
+                 * - channel's deterministic flag is not set
+                 * - dependency on sync framework, which could make the
+                 *   behavior of the clean-up operation non-deterministic
+                 *   (should not be performed in the submit path)
+                 * - channel wdt
+                 * - GPU rail-gating with non-deterministic channels
+                 * - buffer refcounting
+                 *
+                 * If none of the conditions are met, then deferred clean-up
+                 * is not required, and we clean-up one job-tracking
+                 * resource in the submit path.
+                 */
+                need_deferred_cleanup = !c->deterministic ||
+                                        need_sync_framework ||
+                                        c->wdt_enabled ||
+                                        (g->can_railgate &&
+                                         !c->deterministic) ||
+                                        !skip_buffer_refcounting;
+
+                /*
+                 * For deterministic channels, we don't allow deferred clean_up
+                 * processing to occur. In cases we hit this, we fail the submit
+                 */
+                if (c->deterministic && need_deferred_cleanup)
+                        return -EINVAL;
+
+                if (!c->deterministic) {
+                        /*
+                         * Get a power ref unless this is a deterministic
+                         * channel that holds them during the channel lifetime.
+                         * This one is released by gk20a_channel_clean_up_jobs,
+                         * via syncpt or sema interrupt, whichever is used.
+                         */
+                        err = gk20a_busy(g);
+                        if (err) {
+                                nvgpu_err(g,
+                                        "failed to host gk20a to submit gpfifo, process %s",
+                                        current->comm);
+                                return err;
+                        }
+                }
+
+                if (!need_deferred_cleanup) {
+                        /* clean up a single job */
+                        gk20a_channel_clean_up_jobs(c, false);
+                }
+        }
+
+
+        /* Grab access to HW to deal with do_idle */
+        if (c->deterministic)
+                nvgpu_rwsem_down_read(&g->deterministic_busy);
+
+        if (c->deterministic && c->deterministic_railgate_allowed) {
+                /*
+                 * Nope - this channel has dropped its own power ref. As
+                 * deterministic submits don't hold power on per each submitted
+                 * job like normal ones do, the GPU might railgate any time now
+                 * and thus submit is disallowed.
+                 */
+                err = -EINVAL;
+                goto clean_up;
+        }
+
+        trace_gk20a_channel_submit_gpfifo(g->name,
+                                          c->chid,
+                                          num_entries,
+                                          flags,
+                                          fence ? fence->id : 0,
+                                          fence ? fence->value : 0);
+
+        gk20a_dbg_info("pre-submit put %d, get %d, size %d",
+                c->gpfifo.put, c->gpfifo.get, c->gpfifo.entry_num);
+
+        /*
+         * Make sure we have enough space for gpfifo entries. Check cached
+         * values first and then read from HW. If no space, return EAGAIN
+         * and let userpace decide to re-try request or not.
+         */
+        if (nvgpu_gp_free_count(c) < num_entries + extra_entries) {
+                if (nvgpu_get_gp_free_count(c) < num_entries + extra_entries) {
+                        err = -EAGAIN;
+                        goto clean_up;
+                }
+        }
+
+        if (c->has_timedout) {
+                err = -ETIMEDOUT;
+                goto clean_up;
+        }
+
+        if (need_job_tracking) {
+                err = channel_gk20a_alloc_job(c, &job);
+                if (err)
+                        goto clean_up;
+
+                err = gk20a_submit_prepare_syncs(c, fence, job,
+                                                 &wait_cmd, &incr_cmd,
+                                                 &pre_fence, &post_fence,
+                                                 force_need_sync_fence,
+                                                 need_deferred_cleanup,
+                                                 flags);
+                if (err)
+                        goto clean_up_job;
+        }
+
+        if (profile)
+                profile->timestamp[PROFILE_JOB_TRACKING] = sched_clock();
+
+        if (wait_cmd)
+                gk20a_submit_append_priv_cmdbuf(c, wait_cmd);
+
+        if (gpfifo || user_gpfifo)
+                err = gk20a_submit_append_gpfifo(c, gpfifo, user_gpfifo,
+                                num_entries);
+        if (err)
+                goto clean_up_job;
+
+        /*
+         * And here's where we add the incr_cmd we generated earlier. It should
+         * always run!
+         */
+        if (incr_cmd)
+                gk20a_submit_append_priv_cmdbuf(c, incr_cmd);
+
+        if (fence_out)
+                *fence_out = gk20a_fence_get(post_fence);
+
+        if (need_job_tracking)
+                /* TODO! Check for errors... */
+                gk20a_channel_add_job(c, job, skip_buffer_refcounting);
+        if (profile)
+                profile->timestamp[PROFILE_APPEND] = sched_clock();
+
+        g->ops.fifo.userd_gp_put(g, c);
+
+        if ((NVGPU_SUBMIT_GPFIFO_FLAGS_RESCHEDULE_RUNLIST & flags) &&
+                g->ops.fifo.reschedule_runlist)
+                g->ops.fifo.reschedule_runlist(g, c->runlist_id);
+
+        /* No hw access beyond this point */
+        if (c->deterministic)
+                nvgpu_rwsem_up_read(&g->deterministic_busy);
+
+        trace_gk20a_channel_submitted_gpfifo(g->name,
+                                c->chid,
+                                num_entries,
+                                flags,
+                                post_fence ? post_fence->syncpt_id : 0,
+                                post_fence ? post_fence->syncpt_value : 0);
+
+        gk20a_dbg_info("post-submit put %d, get %d, size %d",
+                c->gpfifo.put, c->gpfifo.get, c->gpfifo.entry_num);
+
+        if (profile)
+                profile->timestamp[PROFILE_END] = sched_clock();
+        gk20a_dbg_fn("done");
+        return err;
+
+clean_up_job:
+        channel_gk20a_free_job(c, job);
+clean_up:
+        gk20a_dbg_fn("fail");
+        gk20a_fence_put(pre_fence);
+        gk20a_fence_put(post_fence);
+        if (c->deterministic)
+                nvgpu_rwsem_up_read(&g->deterministic_busy);
+        else if (need_deferred_cleanup)
+                gk20a_idle(g);
+
+        return err;
+}
+