From efe9e3e9ff96a06f50d94dc93ad2c19085fa3d09 Mon Sep 17 00:00:00 2001 From: Mario Kleiner Date: Tue, 27 Feb 2018 06:51:59 +0100 Subject: [PATCH] modesetting: Fix fallback for lack of new vblank kernel API. Turns out that the kernel DRM ioctl handling returns EINVAL instead of ENOTTY if one tries to call the new drmCrtcGetSequence() or drmCrtcQueueSequence() ioctl's introduced in Linux 4.15 on an older kernel where they are missing. This causes the fallback code not to fall back to the old drmWaitVblank() ioctl and thereby failure of vblank stuff. E.g., on Linux 4.13, glxgears -info runs unthrottled at 10000 fps instead of 60 fps. Also breakage of OML_sync_control extension. Check for errno != EINVAL before setting has_queue_sequence = TRUE. Additionally in case of supported drmCrtcQueueSequence(), set has_queue_sequence = TRUE on success, or we might get at least a temporary failure in ms_queue_vblank(). One slight ambiguity is that we can also get EINVAL if drm_crtc_vblank_get() fails in the kernel, so if that happened at first invocation of the new api, we'd fall back to drmWaitVblank() and then fail there, instead of failing in the new api, but the end result would be the same. Fixes: 44d5f2eb8a2f ("xf86-video-modesetting: Support new vblank kernel API [v2]") Signed-off-by: Mario Kleiner Cc: Keith Packard Reviewed-by: Keith Packard --- hw/xfree86/drivers/modesetting/vblank.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/hw/xfree86/drivers/modesetting/vblank.c b/hw/xfree86/drivers/modesetting/vblank.c index e7879f504..1d331ccdb 100644 --- a/hw/xfree86/drivers/modesetting/vblank.c +++ b/hw/xfree86/drivers/modesetting/vblank.c @@ -189,7 +189,7 @@ ms_get_kernel_ust_msc(xf86CrtcPtr crtc, ret = drmCrtcGetSequence(ms->fd, drmmode_crtc->mode_crtc->crtc_id, msc, &ns); - if (ret != -1 || errno != ENOTTY) { + if (ret != -1 || (errno != ENOTTY && errno != EINVAL)) { ms->has_queue_sequence = TRUE; if (ret == 0) *ust = ns / 1000; @@ -246,10 +246,11 @@ ms_queue_vblank(xf86CrtcPtr crtc, ms_queue_flag flags, if (ret == 0) { if (msc_queued) *msc_queued = ms_kernel_msc_to_crtc_msc(crtc, kernel_queued); + ms->has_queue_sequence = TRUE; return TRUE; } - if (ret != -1 || errno != ENOTTY) { + if (ret != -1 || (errno != ENOTTY && errno != EINVAL)) { ms->has_queue_sequence = TRUE; goto check; }