[PATCH] drm/amd/display: do not allocate display_mode_lib unnecessarily

From: Dor Askayo <dor.askayo@gmail.com>
To: amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	linux-kernel@vger.kernel.org
Cc: "Dor Askayo" <dor.askayo@gmail.com>,
	"Harry Wentland" <harry.wentland@amd.com>,
	"Leo Li" <sunpeng.li@amd.com>,
	"Alex Deucher" <alexander.deucher@amd.com>,
	"Christian König" <christian.koenig@amd.com>,
	"David (ChunMing) Zhou" <David1.Zhou@amd.com>,
	"David Airlie" <airlied@linux.ie>,
	"Daniel Vetter" <daniel@ffwll.ch>
Subject: [PATCH] drm/amd/display: do not allocate display_mode_lib unnecessarily
Date: Sat,  4 Jan 2020 14:22:15 +0200	[thread overview]
Message-ID: <20200104122217.148883-1-dor.askayo@gmail.com> (raw)

This allocation isn't required and can fail when resuming from suspend.

Bug: https://gitlab.freedesktop.org/drm/amd/issues/1009
Signed-off-by: Dor Askayo <dor.askayo@gmail.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index dd4731ab935c..83ebb716166b 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -2179,12 +2179,7 @@ void dc_set_power_state(
 	enum dc_acpi_cm_power_state power_state)
 {
 	struct kref refcount;
-	struct display_mode_lib *dml = kzalloc(sizeof(struct display_mode_lib),
-						GFP_KERNEL);
-
-	ASSERT(dml);
-	if (!dml)
-		return;
+	struct display_mode_lib *dml;
 
 	switch (power_state) {
 	case DC_ACPI_CM_POWER_STATE_D0:
@@ -2206,6 +2201,12 @@ void dc_set_power_state(
 		 * clean state, and dc hw programming optimizations will not
 		 * cause any trouble.
 		 */
+		dml = kzalloc(sizeof(struct display_mode_lib),
+				GFP_KERNEL);
+
+		ASSERT(dml);
+		if (!dml)
+			return;
 
 		/* Preserve refcount */
 		refcount = dc->current_state->refcount;
@@ -2219,10 +2220,10 @@ void dc_set_power_state(
 		dc->current_state->refcount = refcount;
 		dc->current_state->bw_ctx.dml = *dml;
 
+		kfree(dml);
+
 		break;
 	}
-
-	kfree(dml);
 }
 
 void dc_resume(struct dc *dc)
-- 
2.24.1

