From fc508eabe2ed808c4b2258bdbbab5940b8c9a0f8 Mon Sep 17 00:00:00 2001 From: Anthony Pesch Date: Sun, 23 May 2021 15:59:20 -0400 Subject: [PATCH] kmsdrm: remove redundant modeset_pending flag this variable was added in commit 2067a7db8e4a36ba40ab34a55b3166ca28638a60 and ultimately tracks if this is a surface's first present. checking if the current bo is NULL provides the same functionality and cuts down on a redundant piece of state potentially getting out of sync in the future --- src/video/kmsdrm/SDL_kmsdrmopengles.c | 90 +++++++++++++-------------- src/video/kmsdrm/SDL_kmsdrmvideo.c | 6 -- src/video/kmsdrm/SDL_kmsdrmvideo.h | 2 - 3 files changed, 42 insertions(+), 56 deletions(-) diff --git a/src/video/kmsdrm/SDL_kmsdrmopengles.c b/src/video/kmsdrm/SDL_kmsdrmopengles.c index 7b28c55bc..55a53df76 100644 --- a/src/video/kmsdrm/SDL_kmsdrmopengles.c +++ b/src/video/kmsdrm/SDL_kmsdrmopengles.c @@ -141,64 +141,58 @@ KMSDRM_GLES_SwapWindow(_THIS, SDL_Window * window) { return 0; } - /* Do we have a modeset pending? If so, configure the new mode on the CRTC. - Has to be done before next pageflip issues, so the buffer with the - new size is big enough for preventing CRTC from reading out of bounds. */ - if (dispdata->modeset_pending) { - + if (!windata->bo) { + /* On the first swap, immediately present the new front buffer. Before + drmModePageFlip can be used the CRTC has to be configured to use + the current connector and mode with drmModeSetCrtc */ ret = KMSDRM_drmModeSetCrtc(viddata->drm_fd, dispdata->crtc->crtc_id, fb_info->fb_id, 0, 0, &dispdata->connector->connector_id, 1, &dispdata->mode); - dispdata->modeset_pending = SDL_FALSE; - if (ret) { SDL_LogError(SDL_LOG_CATEGORY_VIDEO, "Could not set videomode on CRTC."); return 0; } - - /* It's OK to return now if we have done a drmModeSetCrtc(), - it has done the pageflip and blocked until it was done. */ - return 1; - } - - /* Issue pageflip on the next front buffer. - Remember: drmModePageFlip() never blocks, it just issues the flip, - which will be done during the next vblank, or immediately if - we pass the DRM_MODE_PAGE_FLIP_ASYNC flag. - Since calling drmModePageFlip() will return EBUSY if we call it - without having completed the last issued flip, we must pass the - DRM_MODE_PAGE_FLIP_ASYNC if we don't block on EGL (egl_swapinterval = 0). - That makes it flip immediately, without waiting for the next vblank - to do so, so even if we don't block on EGL, the flip will have completed - when we get here again. */ - - if (_this->egl_data->egl_swapinterval == 0 && viddata->async_pageflip_support) { - flip_flags |= DRM_MODE_PAGE_FLIP_ASYNC; - } - - ret = KMSDRM_drmModePageFlip(viddata->drm_fd, dispdata->crtc->crtc_id, - fb_info->fb_id, flip_flags, &windata->waiting_for_flip); - - if (ret == 0) { - windata->waiting_for_flip = SDL_TRUE; } else { - SDL_LogError(SDL_LOG_CATEGORY_VIDEO, "Could not queue pageflip: %d", ret); - } + /* On subsequent swaps, queue the new front buffer to be flipped during + the next vertical blank - /* Wait immediately for vsync (as if we only had two buffers). - Even if we are already doing a WaitPageflip at the begining of this - function, this is NOT redundant because here we wait immediately - after submitting the image to the screen, reducing lag, and if - we have waited here, there won't be a pending pageflip so the - WaitPageflip at the beggining of this function will be a no-op. - Just leave it here and don't worry. - Run your SDL2 program with "SDL_KMSDRM_DOUBLE_BUFFER=1 " - to enable this. */ - if (windata->double_buffer) { - if (!KMSDRM_WaitPageflip(_this, windata)) { - SDL_LogError(SDL_LOG_CATEGORY_VIDEO, "Immediate wait for previous pageflip failed"); - return 0; + Remember: drmModePageFlip() never blocks, it just issues the flip, + which will be done during the next vblank, or immediately if + we pass the DRM_MODE_PAGE_FLIP_ASYNC flag. + Since calling drmModePageFlip() will return EBUSY if we call it + without having completed the last issued flip, we must pass the + DRM_MODE_PAGE_FLIP_ASYNC if we don't block on EGL (egl_swapinterval = 0). + That makes it flip immediately, without waiting for the next vblank + to do so, so even if we don't block on EGL, the flip will have completed + when we get here again. */ + if (_this->egl_data->egl_swapinterval == 0 && viddata->async_pageflip_support) { + flip_flags |= DRM_MODE_PAGE_FLIP_ASYNC; + } + + ret = KMSDRM_drmModePageFlip(viddata->drm_fd, dispdata->crtc->crtc_id, + fb_info->fb_id, flip_flags, &windata->waiting_for_flip); + + if (ret == 0) { + windata->waiting_for_flip = SDL_TRUE; + } else { + SDL_LogError(SDL_LOG_CATEGORY_VIDEO, "Could not queue pageflip: %d", ret); + } + + /* Wait immediately for vsync (as if we only had two buffers). + Even if we are already doing a WaitPageflip at the begining of this + function, this is NOT redundant because here we wait immediately + after submitting the image to the screen, reducing lag, and if + we have waited here, there won't be a pending pageflip so the + WaitPageflip at the beggining of this function will be a no-op. + Just leave it here and don't worry. + Run your SDL2 program with "SDL_KMSDRM_DOUBLE_BUFFER=1 " + to enable this. */ + if (windata->double_buffer) { + if (!KMSDRM_WaitPageflip(_this, windata)) { + SDL_LogError(SDL_LOG_CATEGORY_VIDEO, "Immediate wait for previous pageflip failed"); + return 0; + } } } diff --git a/src/video/kmsdrm/SDL_kmsdrmvideo.c b/src/video/kmsdrm/SDL_kmsdrmvideo.c index 3f9de064e..56c5ef972 100644 --- a/src/video/kmsdrm/SDL_kmsdrmvideo.c +++ b/src/video/kmsdrm/SDL_kmsdrmvideo.c @@ -551,7 +551,6 @@ void KMSDRM_AddDisplay (_THIS, drmModeConnector *connector, drmModeRes *resource /* Initialize some of the members of the new display's driverdata to sane values. */ - dispdata->modeset_pending = SDL_FALSE; dispdata->cursor_bo = NULL; /* Since we create and show the default cursor on KMSDRM_InitMouse(), @@ -1073,7 +1072,6 @@ KMSDRM_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode) /* Take note of the new mode to be set, and leave the CRTC modeset pending so it's done in SwapWindow. */ dispdata->mode = conn->modes[modedata->mode_index]; - dispdata->modeset_pending = SDL_TRUE; for (i = 0; i < viddata->num_windows; i++) { SDL_Window *window = viddata->windows[i]; @@ -1256,9 +1254,6 @@ KMSDRM_CreateWindow(_THIS, SDL_Window * window) dispdata->mode = dispdata->original_mode; } - /* Take note to do the modesettng on the CRTC in SwapWindow. */ - dispdata->modeset_pending = SDL_TRUE; - /* Create the window surfaces with the size we have just chosen. Needs the window diverdata in place. */ if ((ret = KMSDRM_CreateSurfaces(_this, window))) { @@ -1348,7 +1343,6 @@ KMSDRM_ReconfigureWindow( _THIS, SDL_Window * window) /* Recreate the GBM (and EGL) surfaces, and mark the CRTC mode/fb setting as pending so it's done on SwapWindow. */ KMSDRM_CreateSurfaces(_this, window); - dispdata->modeset_pending = SDL_TRUE; /* Tell app about the size we have determined for the window, so SDL pre-scales to that size for us. */ diff --git a/src/video/kmsdrm/SDL_kmsdrmvideo.h b/src/video/kmsdrm/SDL_kmsdrmvideo.h index 18e90abc2..c82a849df 100644 --- a/src/video/kmsdrm/SDL_kmsdrmvideo.h +++ b/src/video/kmsdrm/SDL_kmsdrmvideo.h @@ -80,8 +80,6 @@ typedef struct SDL_DisplayData uint64_t cursor_w, cursor_h; SDL_bool default_cursor_init; - SDL_bool modeset_pending; - } SDL_DisplayData; typedef struct SDL_WindowData