gpu: nvgpu: Do not realloc perfmon sample buffer

Allocate perfmon sample buffer only once.

Bug 1512840

Change-Id: I3f2a62b0fa28e6ba984ae3068a1d56ba461a0c29
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/408180
Reviewed-by: Thomas Cherry <tcherry@nvidia.com>
Tested-by: Thomas Cherry <tcherry@nvidia.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c b/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
index 9b8602c5..c12496bb 100644
--- a/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
@@ -2156,7 +2156,7 @@ static int pmu_init_perfmon(struct pmu_gk20a *pmu)
         struct pmu_payload payload;
         u32 seq;
         u32 data;
-        int err;
+        int err = 0;
 
         gk20a_dbg_fn("");
 
@@ -2206,8 +2206,9 @@ static int pmu_init_perfmon(struct pmu_gk20a *pmu)
                         pwr_pmu_idle_ctrl_filter_disabled_f());
         gk20a_writel(g, pwr_pmu_idle_ctrl_r(2), data);
 
-        pmu->sample_buffer = 0;
-        err = pmu->dmem.alloc(&pmu->dmem, &pmu->sample_buffer, 2 * sizeof(u16));
+        if (!pmu->sample_buffer)
+                err = pmu->dmem.alloc(&pmu->dmem,
+                                      &pmu->sample_buffer, 2 * sizeof(u16));
         if (err) {
                 gk20a_err(dev_from_gk20a(g),
                         "failed to allocate perfmon sample buffer");