gpu: nvgpu: rename has_timedout and make it thread safe

Currently has_timedout variable is protected by wmb at places
where it is being set and there is no correspoding rmb whenever
has_timedout variable is read. This is prone to errors for
concurrent execution. This change is supposed to fix this issue.
Rename has_timedout variable of channel struct to ch_timedout.
Also to avoid rmb every time ch_timedout is read,
ch_timedout_spinlock is added to protect ch_timedout
variable for taking care of concurrent execution.

Bug 2404865
Bug 2092051

Change-Id: I0bee9f50af0a48720aa8b54cbc3af97ef9f6df00
Signed-off-by: Seema Khowala <seemaj@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1930935
Signed-off-by: Debarshi Dutta <ddutta@nvidia.com>
(cherry picked from commit 1f54ea09e3445d9ca3cf7a69b4967849cc9defc8
in dev-kernel)
Reviewed-on: https://git-master.nvidia.com/r/2016975
GVS: Gerrit_Virtual_Submit
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c b/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c
index 234f6fd4..4055d5af 100644
--- a/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c
+++ b/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c
@@ -651,7 +651,7 @@ int vgpu_fifo_force_reset_ch(struct channel_gk20a *ch,
                         if (gk20a_channel_get(ch_tsg)) {
                                 g->ops.fifo.set_error_notifier(ch_tsg,
                                                                 err_code);
-                                ch_tsg->has_timedout = true;
+                                gk20a_channel_set_timedout(ch_tsg);
                                 gk20a_channel_put(ch_tsg);
                         }
                 }
@@ -659,7 +659,7 @@ int vgpu_fifo_force_reset_ch(struct channel_gk20a *ch,
                 nvgpu_rwsem_up_read(&tsg->ch_list_lock);
         } else {
                 g->ops.fifo.set_error_notifier(ch, err_code);
-                ch->has_timedout = true;
+                gk20a_channel_set_timedout(ch);
         }
 
         msg.cmd = TEGRA_VGPU_CMD_CHANNEL_FORCE_RESET;
@@ -685,8 +685,8 @@ static void vgpu_fifo_set_ctx_mmu_error_ch(struct gk20a *g,
                 NVGPU_ERR_NOTIFIER_FIFO_ERROR_MMU_ERR_FLT);
 
         /* mark channel as faulted */
-        ch->has_timedout = true;
-        nvgpu_smp_wmb();
+        gk20a_channel_set_timedout(ch);
+
         /* unblock pending waits */
         nvgpu_cond_broadcast_interruptible(&ch->semaphore_wq);
         nvgpu_cond_broadcast_interruptible(&ch->notifier_wq);