gpu: nvgpu: support binding multiple channels to a debug session

We currently bind only one channel to a debug session
But some use cases might need multiple channels bound
to same debug session

Add this support by adding a list of channels to debug session.
List structure is implemented as struct dbg_session_channel_data

List node dbg_s_list_node is currently defined in struct
dbg_session_gk20a. But this is inefficient when we need to
add debug session to multiple channels

Hence add new reference structure dbg_session_data to
store dbg_session pointer and list entry

For each NVGPU_DBG_GPU_IOCTL_BIND_CHANNEL call, create
two reference structure dbg_session_channel_data for channel
and dbg_session_data for debug session and bind them together

Define API nvgpu_dbg_gpu_get_session_channel() which will
get first channel in the list of debug session
Use this API wherever we refer to channel bound to debug
session

Remove dbg_sessions define in struct gk20a since it is
not being used anywhere

Add new API NVGPU_DBG_GPU_IOCTL_UNBIND_CHANNEL to support
unbinding of channel from debug sesssion

Bug 200156699

Change-Id: I3bfa6f9cd5b90e7254a75c7e64ac893739776b7f
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/1120331
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/regops_gk20a.c b/drivers/gpu/nvgpu/gk20a/regops_gk20a.c
index fda480cf..6e21e857 100644
--- a/drivers/gpu/nvgpu/gk20a/regops_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/regops_gk20a.c
@@ -390,7 +390,7 @@ int exec_regops_gk20a(struct dbg_session_gk20a *dbg_s,
 
         gk20a_dbg(gpu_dbg_fn | gpu_dbg_gpu_dbg, "");
 
-        ch = dbg_s->ch;
+        ch = nvgpu_dbg_gpu_get_session_channel(dbg_s);
 
         /* For vgpu, the regops routines need to be handled in the
          * context of the server and support for that does not exist.
@@ -559,6 +559,9 @@ static bool check_whitelists(struct dbg_session_gk20a *dbg_s,
 {
         struct gk20a *g = dbg_s->g;
         bool valid = false;
+        struct channel_gk20a *ch;
+
+        ch = nvgpu_dbg_gpu_get_session_channel(dbg_s);
 
         if (op->type == REGOP(TYPE_GLOBAL)) {
                 /* search global list */
@@ -570,7 +573,7 @@ static bool check_whitelists(struct dbg_session_gk20a *dbg_s,
                         regop_bsearch_range_cmp);
 
                 /* if debug session and channel is bound search context list */
-                if ((!valid) && (!dbg_s->is_profiler && dbg_s->ch)) {
+                if ((!valid) && (!dbg_s->is_profiler && ch)) {
                         /* binary search context list */
                         valid = g->ops.regops.get_context_whitelist_ranges &&
                                 !!bsearch(&offset,
@@ -581,7 +584,7 @@ static bool check_whitelists(struct dbg_session_gk20a *dbg_s,
                 }
 
                 /* if debug session and channel is bound search runcontrol list */
-                if ((!valid) && (!dbg_s->is_profiler && dbg_s->ch)) {
+                if ((!valid) && (!dbg_s->is_profiler && ch)) {
                         valid = g->ops.regops.get_runcontrol_whitelist &&
                                 linear_search(offset,
                                 g->ops.regops.get_runcontrol_whitelist(),
@@ -589,7 +592,7 @@ static bool check_whitelists(struct dbg_session_gk20a *dbg_s,
                 }
         } else if (op->type == REGOP(TYPE_GR_CTX)) {
                 /* it's a context-relative op */
-                if (!dbg_s->ch) {
+                if (!ch) {
                         gk20a_err(dbg_s->dev, "can't perform ctx regop unless bound");
                         op->status = REGOP(STATUS_UNSUPPORTED_OP);
                         return valid;
@@ -604,7 +607,7 @@ static bool check_whitelists(struct dbg_session_gk20a *dbg_s,
                         regop_bsearch_range_cmp);
 
                 /* if debug session and channel is bound search runcontrol list */
-                if ((!valid) && (!dbg_s->is_profiler && dbg_s->ch)) {
+                if ((!valid) && (!dbg_s->is_profiler && ch)) {
                         valid = g->ops.regops.get_runcontrol_whitelist &&
                                 linear_search(offset,
                                 g->ops.regops.get_runcontrol_whitelist(),