kernel/drivers/gpu/drm/drm_debugfs_crc.c, branch linux-4.17.y

drm/crc: Add support for polling on the data fd.

2018-02-05T12:22:44Z

This will make it possible for userspace to know whether reading will block, without blocking on the fd. This makes it possible to drain all queued CRC's in blocking mode, without having to reopen the fd. Signed-off-by: Maarten Lankhorst Link: https://patchwork.freedesktop.org/patch/msgid/20180202142743.68527-1-maarten.lankhorst@linux.intel.com Reviewed-by: Ville Syrjälä [mlankhorst: Use POLLIN|POLLRDNORM, based on Ville's suggestion]

drm/atomic: Prepare drm_modeset_lock infrastructure for interruptible waiting, v2.

2017-09-13T07:50:52Z

When we want to make drm_atomic_commit interruptible, there are a lot of places that call the lock function, which we don't have control over. Rather than trying to convert every single one, it's easier to toggle interruptible waiting per acquire_ctx. If drm_modeset_acquire_init is called with DRM_MODESET_ACQUIRE_INTERRUPTIBLE, then we will perform interruptible waits in drm_modeset_lock and drm_modeset_backoff. Changes since v1: - Fix locking example in drm_modeset_lock.c to be compatible with interruptible waiting (xexaxo) and make it default. Uninterruptible waiting shouldn't happen except in corner cases, but the example will still apply if the flag is removed. - Add drm_modeset_lock_single_interruptible() to documentation. - Fix dead link to removed drm_modeset_lock_interruptible() in drm_modeset_lock(). Signed-off-by: Maarten Lankhorst Reviewed-by: Daniel Vetter #v1 Cc: Emil Velikov Link: https://patchwork.freedesktop.org/patch/msgid/20170912133749.6532-2-maarten.lankhorst@linux.intel.com Reviewed-by: Emil Velikov

drm/crc: Only open CRC on atomic drivers when the CRTC is active.

2017-07-17T14:34:51Z

Commit e8fa5671183c ("drm: crc: Wait for a frame before returning from open()") adds a wait for CRC frame, but with the CRTC off this will never be generated. For atomic drivers we know if a CRTC is active through crtc_state->active, so when inactive reject the open with -EIO. Just like with the previous patch changing debugfs opening semantics, this patch has been tested against igt. Signed-off-by: Maarten Lankhorst Fixes: e8fa5671183c ("drm: crc: Wait for a frame before returning from open()") Testcase: debugfs_test.read_all_entries Link: http://patchwork.freedesktop.org/patch/msgid/15f9d300-65d3-63aa-00e3-e83f5e4d5a7a@linux.intel.com Reviewed-by: Daniel Vetter

drm/crc: Handle opening and closing crc better

2017-07-17T14:32:43Z

When I was doing a grep . -r /sys/kernel/debug/dri/0 I noticed a WARN appearing when I aborted the grep with ^C. After investigating I've also noticed that the error handling was lacking and there are race conditions involving multiple calls to open/close simultaneously. Fix this by setting the opened flag first and using crc->entries to decide when crc can be collected. Also call unset crc source before cleaning up, this way there is no race with a future open(). This patch has been tested with all the tests in igt with CRC in their name. Signed-off-by: Maarten Lankhorst Link: http://patchwork.freedesktop.org/patch/msgid/20170621110007.11674-1-maarten.lankhorst@linux.intel.com Reviewed-by: Tomeu Vizoso [mlankhorst: Add description that this patch has been tested with IGT, based on tomeu's feedback]

Revert "drm: Don't allow interruptions when opening debugfs/crc"

2017-04-07T20:18:28Z

This reverts commit b8dfa821c27046ede9bf8eb14cc8109d379428e9 Author: Chris Wilson Date: Fri Apr 7 12:17:12 2017 +0100 drm: Don't allow interruptions when opening debugfs/crc It reportedly breaks things, so let's revert now and try again later. Fixes: b8dfa821c270 ("drm: Don't allow interruptions when opening debugfs/crc") Cc: Chris Wilson Cc: Tomeu Vizoso Cc: Daniel Vetter Cc: Daniel Vetter Cc: Jani Nikula Cc: Sean Paul Cc: David Airlie Cc: dri-devel@lists.freedesktop.org Reported-by: Chris Wilson Acked-by: Chris Wilson Acked-by: Daniel Vetter Signed-off-by: Sean Paul

drm: Don't allow interruptions when opening debugfs/crc

2017-04-07T16:42:23Z

The code does not like to be interrupted when waiting for the first vblank after opening a debugfs/crc channel, so don't. [66285.716870] WARNING: CPU: 1 PID: 16615 at drivers/gpu/drm/drm_debugfs_crc.c:185 crtc_crc_open+0x1d0/0x1f0 [drm] [66285.716877] Modules linked in: i915 intel_powerclamp crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel cryptd intel_gtt i2c_algo_bit lpc_ich mfd_core drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops prime_numbers drm video button autofs4 sd_mod ahci libahci libata i2c_i801 scsi_mod i2c_designware_platform i2c_designware_core i2c_core [66285.716929] CPU: 1 PID: 16615 Comm: kms_frontbuffer Not tainted 4.11.0-rc5+ #7 [66285.716935] Hardware name: GIGABYTE GB-BXBT-1900/MZBAYAB-00, BIOS F8 03/02/2016 [66285.716941] Call Trace: [66285.716955] dump_stack+0x4d/0x6f [66285.716966] __warn+0xc1/0xe0 [66285.716975] warn_slowpath_null+0x18/0x20 [66285.717004] crtc_crc_open+0x1d0/0x1f0 [drm] [66285.717014] ? wake_atomic_t_function+0x50/0x50 [66285.717024] full_proxy_open+0xf0/0x1b0 [66285.717032] ? full_proxy_release+0x80/0x80 [66285.717042] do_dentry_open.isra.17+0x14b/0x2d0 [66285.717051] vfs_open+0x42/0x60 [66285.717064] path_openat+0x5e7/0x13d0 [66285.717074] ? refcount_dec_and_test+0x11/0x20 [66285.717081] ? down_read+0xd/0x30 [66285.717087] do_filp_open+0x85/0xf0 [66285.717093] ? __vfs_write+0x23/0x120 [66285.717100] ? __alloc_fd+0x3a/0x170 [66285.717107] do_sys_open+0x11e/0x1f0 [66285.717113] ? do_sys_open+0x11e/0x1f0 [66285.717119] SyS_openat+0xf/0x20 [66285.717125] entry_SYSCALL_64_fastpath+0x17/0x98 [66285.717131] RIP: 0033:0x7f5f2235146a [66285.717135] RSP: 002b:00007ffd892e6bc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 [66285.717142] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5f2235146a [66285.717147] RDX: 0000000000000000 RSI: 00007ffd892e6c40 RDI: 0000000000000006 [66285.717151] RBP: 00007ffd892e6b20 R08: 0000000000000000 R09: 000000000000000f [66285.717156] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [66285.717161] R13: 00007ffd892e6b10 R14: 0000000000000004 R15: 00000000007e61f4 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100610 Fixes: e8fa5671183c ("drm: crc: Wait for a frame before returning from open()") Signed-off-by: Chris Wilson Cc: Tomeu Vizoso Cc: Daniel Vetter Reviewed-by: Tomeu Vizoso Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170407111712.13962-1-chris@chris-wilson.co.uk

drm: document driver interface for CRC capturing

2017-03-24T08:36:06Z

This was missed in Tomeu's patch. Also remove the kerneldoc for the internal function, we don't document that in general. While at it word-smith the docs slightly for more clarity. Cc: Tomeu Vizoso Reviewed-by: Tomeu Vizoso Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170322083617.13361-4-daniel.vetter@ffwll.ch

drm: crc: Call wake_up_interruptible() each time there is a new CRC entry

2017-01-06T14:23:19Z

Each time new data has being added in CRC list inform reader by calling wake_up_interruptible(). This should avoid to do it in all drivers. Signed-off-by: Benjamin Gaignard Cc: Tomeu Vizoso Cc: Daniel Vetter Reviewed-by: Tomeu Vizoso Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1483694104-25627-1-git-send-email-benjamin.gaignard@linaro.org

drm: crc: Wait for a frame before returning from open()

2017-01-05T08:53:12Z

Don't return from the open() call on the crc/data file until the HW has produced a first frame, as there's great variability in when the HW is able to do that and userspace shouldn't have to guess when this specific HW is ready to start giving frame CRCs. Signed-off-by: Tomeu Vizoso Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170102125912.22305-3-tomeu.vizoso@collabora.com

drm: Move locking into drm_debugfs_crtc_crc_add

2017-01-05T08:53:06Z

There's no reason any more for callers of this function to take the lock themselves, so just move the lock to the function to avoid confusion and bugs when more callers are contributed. Signed-off-by: Tomeu Vizoso Reviewed-by: Emil Velikov Reviewed-by: Robert Foss Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170102125912.22305-2-tomeu.vizoso@collabora.com