gpu: nvgpu: process granularity for FECS traces

When processing FECS traces, a hash table is used
to retrieve the 'pid' of the process that created
the channel/TSG. Report process identifer (aka
tgid in kernel) instead of thread identifier (aka
pid) for FECS traces.

Bug 1736423

Change-Id: I54cb9d298b9fe3e1cccdd7145604cd01c5758c9d
Signed-off-by: Thomas Fleury <tfleury@nvidia.com>
Reviewed-on: http://git-master/r/1166501
(cherry picked from commit f7fd1f6d7ad0753b787ec20604a08a1f4882fe6f)
Reviewed-on: http://git-master/r/1168728
(cherry picked from commit 97a62e5b89352fce576f1bca71b38bf2242ff047)
Reviewed-on: http://git-master/r/1177823
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Richard Zhao <rizhao@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: Vijayakumar Subbu <vsubbu@nvidia.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/fecs_trace_gk20a.c b/drivers/gpu/nvgpu/gk20a/fecs_trace_gk20a.c
index 15e645f2..abf1cc55 100644
--- a/drivers/gpu/nvgpu/gk20a/fecs_trace_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/fecs_trace_gk20a.c
@@ -631,10 +631,14 @@ static int gk20a_fecs_trace_bind_channel(struct gk20a *g,
                         GK20A_FECS_TRACE_NUM_RECORDS));
 
         gk20a_mem_end(g, mem);
+
+        /* pid (process identifier) in user space, corresponds to tgid (thread
+         * group id) in kernel space.
+         */
         if (gk20a_is_channel_marked_as_tsg(ch))
                 pid = tsg_gk20a_from_ch(ch)->tgid;
         else
-                pid = ch->pid;
+                pid = ch->tgid;
         gk20a_fecs_trace_hash_add(g, context_ptr, pid);
 
         return 0;