From 820e1af66588836df00a34c046e4c6ff77a030d8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ma=C3=ADra=20Canal?= <mcanal@igalia.com>
Date: Mon, 15 May 2023 10:52:03 -0300
Subject: drm/vkms: Reduce critical section
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Git-commit: 6c494ca6fd820ca6f4329bfbdcd048466dc752e2
Patch-mainline: v6.6-rc1
References: jsc#PED-3527 jsc#PED-5475 jsc#PED-6068 jsc#PED-6070 jsc#PED-6116 jsc#PED-6120 jsc#PED-5065 jsc#PED-5477 jsc#PED-5511 jsc#PED-6041 jsc#PED-6069 jsc#PED-6071
The spinlock composer_lock protects the variables crc_pending,
wb_pending, frame_start and frame_end, which are variables that are used
by the composer worker. There is no need to protect the wb_frame_info
information with a spinlock. Therefore, reduce the critical section of
the lock by removing the assignments to the wb_frame_info from the
critical section.
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230515135204.115393-2-mcanal@igalia.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/vkms/vkms_writeback.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 84a51cd281b9..9a126f678d73 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -142,11 +142,13 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn,
spin_lock_irq(&output->composer_lock);
crtc_state->active_writeback = active_wb;
+ crtc_state->wb_pending = true;
+ spin_unlock_irq(&output->composer_lock);
+
wb_frame_info->offset = fb->offsets[0];
wb_frame_info->pitch = fb->pitches[0];
wb_frame_info->cpp = fb->format->cpp[0];
- crtc_state->wb_pending = true;
- spin_unlock_irq(&output->composer_lock);
+
drm_writeback_queue_job(wb_conn, connector_state);
active_wb->wb_write = get_line_to_frame_function(wb_format);
drm_rect_init(&wb_frame_info->src, 0, 0, crtc_width, crtc_height);
--
2.43.0