Rename various instances of pagelist to pagereflist. The list now
stores pageref structures, so the new name is more appropriate.
In their write-back helpers, several fbdev drivers refer to the
pageref list in struct fb_deferred_io instead of using the one
supplied as argument to the function. Convert them over to the
supplied one. It's the same instance, so no change of behavior
occurs.
v4:
* fix commit message (Javier)
Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220429100834.18898-5-tzimmermann@suse.de
Store the per-page state for fbdev's deferred I/O in struct
fb_deferred_io_pageref. Maintain a list of pagerefs for the pages
that have to be written back to video memory. Update all affected
drivers.
As with pages before, fbdev acquires a pageref when an mmaped page
of the framebuffer is being written to. It holds the pageref in a
list of all currently written pagerefs until it flushes the written
pages to video memory. Writeback occurs periodically. After writeback
fbdev releases all pagerefs and builds up a new dirty list until the
next writeback occurs.
Using pagerefs has a number of benefits.
For pages of the framebuffer, the deferred I/O code used struct
page.lru as an entry into the list of dirty pages. The lru field is
owned by the page cache, which makes deferred I/O incompatible with
some memory pages (e.g., most notably DRM's GEM SHMEM allocator).
struct fb_deferred_io_pageref now provides an entry into a list of
dirty framebuffer pages, freeing lru for use with the page cache.
Drivers also assumed that struct page.index is the page offset into
the framebuffer. This is not true for DRM buffers, which are located
at various offset within a mapped area. struct fb_deferred_io_pageref
explicitly stores an offset into the framebuffer. struct page.index
is now only the page offset into the mapped area.
These changes will allow DRM to use fbdev deferred I/O without an
intermediate shadow buffer.
v3:
* use pageref->offset for sorting
* fix grammar in comment
v2:
* minor fixes in commit message
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220429100834.18898-3-tzimmermann@suse.de
The fbdev mmap function fb_mmap() unconditionally overrides the
driver's implementation if deferred I/O has been activated. This
makes it hard to implement mmap with anything but a vmalloc()'ed
software buffer. That is specifically a problem for DRM, where
video memory is maintained by a memory manager.
Leave the mmap handling to drivers and expect them to call the
helper for deferred I/O by thmeselves.
v4:
* unlock mm_lock in fb_mmap() error path (Dan)
v3:
* fix warning if fb_mmap is missing (kernel test robot)
v2:
* print a helpful error message if the defio setup is
incorrect (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220429100834.18898-2-tzimmermann@suse.de
Pull drm updates from Dave Airlie:
"Lots of work all over, Intel improving DG2 support, amdkfd CRIU
support, msm new hw support, and faster fbdev support.
dma-buf:
- rename dma-buf-map to iosys-map
core:
- move buddy allocator to core
- add pci/platform init macros
- improve EDID parser deep color handling
- EDID timing type 7 support
- add GPD Win Max quirk
- add yes/no helpers to string_helpers
- flatten syncobj chains
- add nomodeset support to lots of drivers
- improve fb-helper clipping support
- add default property value interface
fbdev:
- improve fbdev ops speed
ttm:
- add a backpointer from ttm bo->ttm resource
dp:
- move displayport headers
- add a dp helper module
bridge:
- anx7625 atomic support, HDCP support
panel:
- split out panel-lvds and lvds bindings
- find panels in OF subnodes
privacy:
- add chromeos privacy screen support
fb:
- hot unplug fw fb on forced removal
simpledrm:
- request region instead of marking ioresource busy
- add panel oreintation property
udmabuf:
- fix oops with 0 pages
amdgpu:
- power management code cleanup
- Enable freesync video mode by default
- RAS code cleanup
- Improve VRAM access for debug using SDMA
- SR-IOV rework special register access and fixes
- profiling power state request ioctl
- expose IP discovery via sysfs
- Cyan skillfish updates
- GC 10.3.7, SDMA 5.2.7, DCN 3.1.6 updates
- expose benchmark tests via debugfs
- add module param to disable XGMI for testing
- GPU reset debugfs register dumping support
amdkfd:
- CRIU support
- SDMA queue fixes
radeon:
- UVD suspend fix
- iMac backlight fix
i915:
- minimal parallel submission for execlists
- DG2-G12 subplatform added
- DG2 programming workarounds
- DG2 accelerated migration support
- flat CCS and CCS engine support for XeHP
- initial small BAR support
- drop fake LMEM support
- ADL-N PCH support
- bigjoiner updates
- introduce VMA resources and async unbinding
- register definitions cleanups
- multi-FBC refactoring
- DG1 OPROM over SPI support
- ADL-N platform enabling
- opregion mailbox #5 support
- DP MST ESI improvements
- drm device based logging
- async flip optimisation for DG2
- CPU arch abstraction fixes
- improve GuC ADS init to work on aarch64
- tweak TTM LRU priority hint
- GuC 69.0.3 support
- remove short term execbuf pins
nouveau:
- higher DP/eDP bitrates
- backlight fixes
msm:
- dpu + dp support for sc8180x
- dp support for sm8350
- dpu + dsi support for qcm2290
- 10nm dsi phy tuning support
- bridge support for dp encoder
- gpu support for additional 7c3 SKUs
ingenic:
- HDMI support for JZ4780
- aux channel EDID support
ast:
- AST2600 support
- add wide screen support
- create DP/DVI connectors
omapdrm:
- fix implicit dma_buf fencing
vc4:
- add CSC + full range support
- better display firmware handoff
panfrost:
- add initial dual-core GPU support
stm:
- new revision support
- fb handover support
mediatek:
- transfer display binding document to yaml format.
- add mt8195 display device binding.
- allow commands to be sent during video mode.
- add wait_for_event for crtc disable by cmdq.
tegra:
- YUV format support
rcar-du:
- LVDS support for M3-W+ (R8A77961)
exynos:
- BGR pixel format for FIMD device"
* tag 'drm-next-2022-03-24' of git://anongit.freedesktop.org/drm/drm: (1529 commits)
drm/i915/display: Do not re-enable PSR after it was marked as not reliable
drm/i915/display: Fix HPD short pulse handling for eDP
drm/amdgpu: Use drm_mode_copy()
drm/radeon: Use drm_mode_copy()
drm/amdgpu: Use ternary operator in `vcn_v1_0_start()`
drm/amdgpu: Remove pointless on stack mode copies
drm/amd/pm: fix indenting in __smu_cmn_reg_print_error()
drm/amdgpu/dc: fix typos in comments
drm/amdgpu: fix typos in comments
drm/amd/pm: fix typos in comments
drm/amdgpu: Add stolen reserved memory for MI25 SRIOV.
drm/amdgpu: Merge get_reserved_allocation to get_vbios_allocations.
drm/amdkfd: evict svm bo worker handle error
drm/amdgpu/vcn: fix vcn ring test failure in igt reload test
drm/amdgpu: only allow secure submission on rings which support that
drm/amdgpu: fixed the warnings reported by kernel test robot
drm/amd/display: 3.2.177
drm/amd/display: [FW Promotion] Release 0.0.108.0
drm/amd/display: Add save/restore PANEL_PWRSEQ_REF_DIV2
drm/amd/display: Wait for hubp read line for Pollock
...
Easily hit the below list corruption:
==
list_add corruption. prev->next should be next (ffffffffc0ceb090), but
was ffffec604507edc8. (prev=ffffec604507edc8).
WARNING: CPU: 65 PID: 3959 at lib/list_debug.c:26
__list_add_valid+0x53/0x80
CPU: 65 PID: 3959 Comm: fbdev Tainted: G U
RIP: 0010:__list_add_valid+0x53/0x80
Call Trace:
<TASK>
fb_deferred_io_mkwrite+0xea/0x150
do_page_mkwrite+0x57/0xc0
do_wp_page+0x278/0x2f0
__handle_mm_fault+0xdc2/0x1590
handle_mm_fault+0xdd/0x2c0
do_user_addr_fault+0x1d3/0x650
exc_page_fault+0x77/0x180
? asm_exc_page_fault+0x8/0x30
asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x7fd98fc8fad1
==
Figure out the race happens when one process is adding &page->lru into
the pagelist tail in fb_deferred_io_mkwrite(), another process is
re-initializing the same &page->lru in fb_deferred_io_fault(), which is
not protected by the lock.
This fix is to init all the page lists one time during initialization,
it not only fixes the list corruption, but also avoids INIT_LIST_HEAD()
redundantly.
V2: change "int i" to "unsigned int i" (Geert Uytterhoeven)
Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Fixes: 105a940416 ("fbdev/defio: Early-out if page is already enlisted")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220318005003.51810-1-chuansheng.liu@intel.com
Fbdev's deferred I/O sorts all dirty pages by default, which incurs a
significant overhead. Make the sorting step optional and update the few
drivers that require it. Use a FIFO list by default.
Most fbdev drivers with deferred I/O build a bounding rectangle around
the dirty pages or simply flush the whole screen. The only two affected
DRM drivers, generic fbdev and vmwgfx, both use a bounding rectangle.
In those cases, the exact order of the pages doesn't matter. The other
drivers look at the page index or handle pages one-by-one. The patch
sets the sort_pagelist flag for those, even though some of them would
probably work correctly without sorting. Driver maintainers should update
their driver accordingly.
Sorting pages by memory offset for deferred I/O performs an implicit
bubble-sort step on the list of dirty pages. The algorithm goes through
the list of dirty pages and inserts each new page according to its
index field. Even worse, list traversal always starts at the first
entry. As video memory is most likely updated scanline by scanline, the
algorithm traverses through the complete list for each updated page.
For example, with 1024x768x32bpp each page covers exactly one scanline.
Writing a single screen update from top to bottom requires updating
768 pages. With an average list length of 384 entries, a screen update
creates (768 * 384 =) 294912 compare operation.
Fix this by making the sorting step opt-in and update the few drivers
that require it. All other drivers work with unsorted page lists. Pages
are appended to the list. Therefore, in the common case of writing the
framebuffer top to bottom, pages are still sorted by offset, which may
have a positive effect on performance.
Playing a video [1] in mplayer's benchmark mode shows the difference
(i7-4790, FullHD, simpledrm, kernel with debugging).
mplayer -benchmark -nosound -vo fbdev ./big_buck_bunny_720p_stereo.ogg
With sorted page lists:
BENCHMARKs: VC: 32.960s VO: 73.068s A: 0.000s Sys: 2.413s = 108.441s
BENCHMARK%: VC: 30.3947% VO: 67.3802% A: 0.0000% Sys: 2.2251% = 100.0000%
With unsorted page lists:
BENCHMARKs: VC: 31.005s VO: 42.889s A: 0.000s Sys: 2.256s = 76.150s
BENCHMARK%: VC: 40.7156% VO: 56.3219% A: 0.0000% Sys: 2.9625% = 100.0000%
VC shows the overhead of video decoding, VO shows the overhead of the
video output. Using unsorted page lists reduces the benchmark's run time
by ~32s/~25%.
v2:
* Make sorted pagelists the special case (Sam)
* Comment on drivers' use of pagelist (Sam)
* Warn about the overhead in comment
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://download.blender.org/peach/bigbuckbunny_movies/big_buck_bunny_720p_stereo.ogg # [1]
Link: https://patchwork.freedesktop.org/patch/msgid/20220211094640.21632-3-tzimmermann@suse.de
Modifying fb_ops directly to override fb_mmap with fb_deferred_io_mmap
and then resetting it to NULL afterwards causes problems all over the
place. First, it prevents making the fbops member of struct fb_info a
const pointer, which means we can't make struct fb_ops const
anywhere. Second, a few places have to go out of their way to restore
the original fb_mmap pointer that gets reset to NULL.
Since the only user of the fbops->fb_mmap hook is fb_mmap() in fbmem.c,
call fb_deferred_io_mmap() directly when deferred IO is enabled, and
avoid modifying fb_ops altogether.
Simply use info->fbdefio to determine whether deferred IO should be used
or not. This should be accurate enough for all use cases, although
perhaps not pedantically correct.
v2: Simplify considerably by calling fb_deferred_io_mmap() directly
(Daniel, Ville)
Cc: Jaya Kumar <jayalk@intworks.biz>
Cc: linux-fbdev@vger.kernel.org
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/022c82429da15d6450ff9ac1a897322ec3124db4.1575022735.git.jani.nikula@intel.com
This patch converts most of the in-kernel filesystems that do writeback
out of the pagecache to report errors using the errseq_t-based
infrastructure that was recently added. This allows them to report
errors once for each open file description.
Most filesystems have a fairly straightforward fsync operation. They
call filemap_write_and_wait_range to write back all of the data and
wait on it, and then (sometimes) sync out the metadata.
For those filesystems this is a straightforward conversion from calling
filemap_write_and_wait_range in their fsync operation to calling
file_write_and_wait_range.
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Export fb_deferred_io_mmap so drivers can change vma->vm_page_prot.
When the framebuffer memory is allocated using dma_alloc_writecombine()
instead of vmalloc(), I get cache syncing problems on ARM.
This solves it:
static int drm_fbdev_cma_deferred_io_mmap(struct fb_info *info,
struct vm_area_struct *vma)
{
fb_deferred_io_mmap(info, vma);
vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
return 0;
}
Could this have been done in the core?
Drivers that don't set (struct fb_ops *)->fb_mmap, gets a call to
fb_pgprotect() at the end of the default fb_mmap implementation
(drivers/video/fbdev/core/fbmem.c). This is an architecture specific
function that on many platforms uses pgprot_writecombine(), but not on
all. And looking at some of the fb_mmap implementations, some of them
sets vm_page_prot to nocache for instance, so I think the safest bet is
to do this in the driver and not in the fbdev core. And we can't call
fb_pgprotect() from fb_deferred_io_mmap() either because we don't have
access to the file pointer that powerpc needs.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1461856717-6476-5-git-send-email-noralf@tronnes.org
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).
Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
CONFIG_FB_DEFERRED_IO is defined as bool while CONFIG_FB is defined as
tristate. Currently fb_defio.o is linked into the kernel image even if
CONFIG_FB=m.
I fix this by updating the Makefile to link fb_defio.o into fb.o and thus
go into one place with the other core framebuffer code.
Signed-off-by: Harald Geyer <harald@ccbib.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
fb_deferred_io_fsync() returns the value of schedule_delayed_work() as
an error code, but schedule_delayed_work() does not return an error. It
returns true/false depending on whether the work was already queued.
Fix this by ignoring the return value of schedule_delayed_work().
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: stable@vger.kernel.org
Instead of having fbdev framework core files at the root fbdev
directory, mixed with random fbdev device drivers, move the fbdev core
files to a separate core directory. This makes it much clearer which of
the files are actually part of the fbdev framework, and which are part
of device drivers.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
