gpu: nvgpu: add support for pre-allocated resources

Add support for pre-allocation of job tracking resources
w/ new (extended) ioctl. Goal is to avoid dynamic memory
allocation in the submit path. This patch does the following:

1) Intoduces a new ioctl, NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX,
which enables pre-allocation of tracking resources per job:
a) 2x priv_cmd_entry
b) 2x gk20a_fence

2) Implements circular ring buffer for job
tracking to avoid lock contention between producer
(submitter) and consumer (clean-up)

Bug 1795076

Change-Id: I6b52e5c575871107ff380f9a5790f440a6969347
Signed-off-by: Sachit Kadle <skadle@nvidia.com>
Reviewed-on: http://git-master/r/1203300
(cherry picked from commit 9fd270c22b860935dffe244753dabd87454bef39)
Reviewed-on: http://git-master/r/1223934
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/uapi/linux/nvgpu.h b/include/uapi/linux/nvgpu.h
index 0bf88628..22e357b6 100644
--- a/include/uapi/linux/nvgpu.h
+++ b/include/uapi/linux/nvgpu.h
@@ -963,7 +963,13 @@ struct nvgpu_alloc_gpfifo_args {
         __u32 num_entries;
 #define NVGPU_ALLOC_GPFIFO_FLAGS_VPR_ENABLED    (1 << 0) /* set owner channel of this gpfifo as a vpr channel */
         __u32 flags;
+};
 
+struct nvgpu_alloc_gpfifo_ex_args {
+        __u32 num_entries;
+        __u32 num_inflight_jobs;
+        __u32 flags;
+        __u32 reserved[5];
 };
 
 struct gk20a_sync_pt_info {
@@ -1182,6 +1188,8 @@ struct nvgpu_preemption_mode_args {
         _IOWR(NVGPU_IOCTL_MAGIC, 18, struct nvgpu_set_timeout_ex_args)
 #define NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO        \
         _IOW(NVGPU_IOCTL_MAGIC,  100, struct nvgpu_alloc_gpfifo_args)
+#define NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX     \
+        _IOW(NVGPU_IOCTL_MAGIC,  101, struct nvgpu_alloc_gpfifo_ex_args)
 #define NVGPU_IOCTL_CHANNEL_WAIT                \
         _IOWR(NVGPU_IOCTL_MAGIC, 102, struct nvgpu_wait_args)
 #define NVGPU_IOCTL_CHANNEL_CYCLE_STATS \