In case ioremap fails, the fix releases resources and returns
-ENOMEM to avoid NULL pointer dereferences.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Cc: Aditya Pakki <pakki001@umn.edu>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[b.zolnierkie: minor patch summary fixup]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
When ioremap fails, hga_vram should not be dereferenced. The fix
check the failure to avoid NULL pointer dereference.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Cc: Aditya Pakki <pakki001@umn.edu>
Cc: Ferenc Bakonyi <fero@drama.obuda.kando.hu>
[b.zolnierkie: minor patch summary fixup]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Simply add all pci memory bars to struct apertures_struct in
remove_conflicting_pci_framebuffers(), without depending on the
res_id parameter.
The plan is to drop the res_id parameter later on. For now keep the
parameter, use it for sanity-checking and warn on inconsistencies.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Formatting of Kconfig files doesn't look so pretty, so let the
Great White Handkerchief come around and clean it up.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
[b.zolnierkie: add missing patch description]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Memory allocated, using kmalloc, for new_compat may fail. This patch
checks for such an error and prevents potential NULL pointer
dereference.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Cc: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warning:
drivers/video/fbdev/xen-fbfront.c: In function ‘xenfb_backend_changed’:
drivers/video/fbdev/xen-fbfront.c:678:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (dev->state == XenbusStateClosed)
^
drivers/video/fbdev/xen-fbfront.c:681:2: note: here
case XenbusStateClosing:
^~~~
Warning level 3 was used: -Wimplicit-fallthrough=3
Notice that, in this particular case, the code comment is modified
in accordance with what GCC is expecting to find.
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Rendering calls may be done simultaneously from the workqueue,
dlfb_ops_write, dlfb_ops_ioctl, dlfb_ops_set_par and dlfb_dpy_deferred_io.
The code is robust enough so that it won't crash on concurrent rendering.
However, concurrent rendering may cause display corruption if the same
pixel is simultaneously being rendered. In order to avoid this corruption,
this patch adds a mutex around the rendering calls.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: <stable@vger.kernel.org>
[b.zolnierkie: replace "dlfb:" with "uldfb:" in the patch summary]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
If a framebuffer device is used as a console, the rendering calls
(copyarea, fillrect, imageblit) may be done with the console spinlock
held. On udlfb, these function call dlfb_handle_damage that takes a
blocking semaphore before acquiring an URB.
In order to fix the bug, this patch changes the calls copyarea, fillrect
and imageblit to offload USB work to a workqueue.
A side effect of this patch is 3x improvement in console scrolling speed
because the device doesn't have to be updated after each copyarea call.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Make the driver OF only as since AVR32 has been removed from the kernel,
there are only OF enabled platform using it.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Add an of_node_put when a tested device node is not available.
The semantic patch that fixes this problem is as follows
(http://coccinelle.lip6.fr):
// <smpl>
@@
identifier f;
local idexpression e;
expression x;
@@
e = f(...);
... when != of_node_put(e)
when != x = e
when != e = x
when any
if (<+...of_device_is_available(e)...+>) {
... when != of_node_put(e)
(
return e;
|
+ of_node_put(e);
return ...;
)
}
// </smpl>
Fixes: f76ee892a9 ("omapfb: copy omapdss & displays for omapfb")
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Don't skip the framebuffer CLUT pointer register initialization when
the first dafb_setpalette() invocation has regno equal to zero.
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
The 'inverse' parameter has no effect otherwise. Remove set-but-unused
variable.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Now the driver has been converted to a platform driver, the legacy
printk() calls without any log level can be replaced by proper dev_*()
calls.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
On Falcon, Atari frame buffer initialization relies on preprogrammed
register values. These register values are changed to blank the
console.
Hence when using kexec to boot into a new kernel while the console is
blanked, the new kernel cannot determine the current video
configuration, and the Atari frame buffer driver fails to initialize:
atafb: phys_screen_base 6ce000 screen_len 4096
Fix this by doing a straight-forward conversion of the driver to a
platform device driver, and adding a shutdown handler that unblanks the
display.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
CONFIG_FB_ATARI is bool, hence the Atari frame buffer driver cannot be
built as a module. In addition, the module support code refers to a
function atafb_deinit(), which never existed.
Replace module_init() by device_initcall().
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
The value of info->var.bits_per_pixel get checked in macfb_setcolreg().
Remove additional checks as they are redundant.
macfb_defined.activate gets initialized to FB_ACTIVATE_NOW by the struct
initializer. Remove redundant assignments.
macfb_defined.bits_per_pixel, .width and .height all get assigned
unconditionally. Remove redundant initializers.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
The indentation in the if statement is not indented correctly, fix
this with extra level of indentation.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
There are a couple of statements that are indented too deeply, fix
this by removing tabs. Also add a space after a comma to clean up
a cppcheck warning.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
The FB_PRE_INIT_FB option keeps the kernel from reinitializing the display
and prevents flickering during the transition from a bootloader splash
screen to the kernel logo screen.
Make this option available for the mxsfb driver.
Signed-off-by: Melchior Franz <melchior.franz@ginzinger.com>
Signed-off-by: Martin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: Manfred Schlaegl <manfred.schlaegl@ginzinger.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Pull aio race fixes and cleanups from Al Viro.
The aio code had more issues with error handling and races with the aio
completing at just the right (wrong) time along with freeing the file
descriptor when another thread closes the file.
Just a couple of these commits are the actual fixes: the others are
cleanups to either make the fixes simpler, or to make the code legible
and understandable enough that we hope there's no more fundamental races
hiding.
* 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
aio: move sanity checks and request allocation to io_submit_one()
deal with get_reqs_available() in aio_get_req() itself
aio: move dropping ->ki_eventfd into iocb_destroy()
make aio_read()/aio_write() return int
Fix aio_poll() races
aio: store event at final iocb_put()
aio: keep io_event in aio_kiocb
aio: fold lookup_kiocb() into its sole caller
pin iocb through aio.
At least McPDM module depends on an external optional clock to be
usable. To make handling of the McPDM clock easier in the following
patches, let's add separate functions for handling the main clocks
and the optional clocks.
Let's also add error handling to shut down already enabled clocks
while at it.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Pull symlink fixes from Al Viro:
"The ceph fix is already in mainline, Daniel's bpf fix is in bpf tree
(1da6c4d914 "bpf: fix use after free in bpf_evict_inode"), the rest
is in here"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
debugfs: fix use-after-free on symlink traversal
ubifs: fix use-after-free on symlink traversal
jffs2: fix use-after-free on symlink traversal
We have ti,no-idle in use in addition to ti,no-idle-on-init but we're
missing handling for it in the ti-sysc interconnect target module driver.
Let's also group the idle defines together and update the binding
documentation for it.
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
If we return early before ddata->clocks have been allocated we will get a
NULL pointer dereference in sysc_unprepare(). Let's fix this by returning
early when no clocks are allocated.
Fixes: 0eecc636e5 ("bus: ti-sysc: Add minimal TI sysc interconnect target driver")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Although we don't actually make use of the 'max_mapnr' global variable,
we do set it to a junk value for !CONFIG_FLATMEM configurations that
leave mem_map uninitialised.
To avoid somebody tripping over this in future, set 'max_mapnr' using
max_pfn, which is calculated directly from the memblock information.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Muchun Song <smuchun@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
A83T DTSI has cpu clocks defined only on the first CPU in each cluster.
We can bring down any CPU in the cluster, so we need to define clock
for each CPU, so that the system knows what clock to use if the first
CPU is down.
Also move the clocks property below the compatible on cpus where it is
already defined. Property "clock-names" is not needed.
Signed-off-by: Ondrej Jirman <megous@megous.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The loop driver always declares the rotational flag of its device as
rotational, even when the device of the mapped file is nonrotational,
as is the case with SSDs or on tmpfs. This can confuse filesystem tools
which are SSD-aware; in my case I frequently forget to tell mkfs.btrfs
that my loop device on tmpfs is nonrotational, and that I really don't
need any automatic metadata redundancy.
The attached patch fixes this by introspecting the rotational flag of the
mapped file's underlying block device, if it exists. If the mapped file's
filesystem has no associated block device - as is the case on e.g. tmpfs -
we assume nonrotational storage. If there is a better way to identify such
non-devices I'd love to hear them.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: holger@applied-asynchrony.com
Signed-off-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Benjamin Gordon <bmgordon@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The execution time of BFQ has been slightly lowered. Report the new
execution time in BFQ documentation.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bfq saves the state of a queue each time a merge occurs, to be
able to resume such a state when the queue is associated again
with its original process, on a split.
Unfortunately bfq does not save & restore also the weight of the
queue. If the weight is not correctly resumed when the queue is
recycled, then the weight of the recycled queue could differ
from the weight of the original queue.
This commit adds the missing save & resume of the weight.
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Francesco Pollicino <fra.fra.800@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The function "bfq_log_bfqq" prints the pid of the process
associated with the queue passed as input.
Unfortunately, if the queue is shared, then more than one process
is associated with the queue. The pid that gets printed in this
case is the pid of one of the associated processes.
Which process gets printed depends on the exact sequence of merge
events the queue underwent. So printing such a pid is rather
useless and above all is often rather confusing because it
reports a random pid between those of the associated processes.
This commit addresses this issue by printing SHARED instead of a pid
if the queue is shared.
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Francesco Pollicino <fra.fra.800@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If many bfq_queues belonging to the same group happen to be created
shortly after each other, then the processes associated with these
queues have typically a common goal. In particular, bursts of queue
creations are usually caused by services or applications that spawn
many parallel threads/processes. Examples are systemd during boot, or
git grep. If there are no other active queues, then, to help these
processes get their job done as soon as possible, the best thing to do
is to reach a high throughput. To this goal, it is usually better to
not grant either weight-raising or device idling to the queues
associated with these processes. And this is exactly what BFQ
currently does.
There is however a drawback: if, in contrast, some other queues are
already active, then the newly created queues must be protected from
the I/O flowing through the already existing queues. In this case, the
best thing to do is the opposite as in the other case: it is much
better to grant weight-raising and device idling to the newly-created
queues, if they deserve it. This commit addresses this issue by doing
so if there are already other active queues.
This change also helps eliminating false positives, which occur when
the newly-created queues do not belong to an actual large burst of
creations, but some background task (e.g., a service) happens to
trigger the creation of new queues in the middle, i.e., very close to
when the victim queues are created. These false positive may cause
total loss of control on process latencies.
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Sync random I/O is likely to be confused with soft real-time I/O,
because it is characterized by limited throughput and apparently
isochronous arrival pattern. To avoid false positives, this commits
prevents bfq_queues containing only random (seeky) I/O from being
tagged as soft real-time.
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To boost throughput with a set of processes doing interleaved I/O
(i.e., a set of processes whose individual I/O is random, but whose
merged cumulative I/O is sequential), BFQ merges the queues associated
with these processes, i.e., redirects the I/O of these processes into a
common, shared queue. In the shared queue, I/O requests are ordered by
their position on the medium, thus sequential I/O gets dispatched to
the device when the shared queue is served.
Queue merging costs execution time, because, to detect which queues to
merge, BFQ must maintain a list of the head I/O requests of active
queues, ordered by request positions. Measurements showed that this
costs about 10% of BFQ's total per-request processing time.
Request processing time becomes more and more critical as the speed of
the underlying storage device grows. Yet, fortunately, queue merging
is basically useless on the very devices that are so fast to make
request processing time critical. To reach a high throughput, these
devices must have many requests queued at the same time. But, in this
configuration, the internal scheduling algorithms of these devices do
also the job of queue merging: they reorder requests so as to obtain
as much as possible a sequential I/O pattern. As a consequence, with
processes doing interleaved I/O, the throughput reached by one such
device is likely to be the same, with and without queue merging.
In view of this fact, this commit disables queue merging, and all
related housekeeping, for non-rotational devices with internal
queueing. The total, single-lock-protected, per-request processing
time of BFQ drops to, e.g., 1.9 us on an Intel Core i7-2760QM@2.40GHz
(time measured with simple code instrumentation, and using the
throughput-sync.sh script of the S suite [1], in performance-profiling
mode). To put this result into context, the total,
single-lock-protected, per-request execution time of the lightest I/O
scheduler available in blk-mq, mq-deadline, is 0.7 us (mq-deadline is
~800 LOC, against ~10500 LOC for BFQ).
Disabling merging provides a further, remarkable benefit in terms of
throughput. Merging tends to make many workloads artificially more
uneven, mainly because of shared queues remaining non empty for
incomparably more time than normal queues. So, if, e.g., one of the
queues in a set of merged queues has a higher weight than a normal
queue, then the shared queue may inherit such a high weight and, by
staying almost always active, may force BFQ to perform I/O plugging
most of the time. This evidently makes it harder for BFQ to let the
device reach a high throughput.
As a practical example of this problem, and of the benefits of this
commit, we measured again the throughput in the nasty scenario
considered in previous commit messages: dbench test (in the Phoronix
suite), with 6 clients, on a filesystem with journaling, and with the
journaling daemon enjoying a higher weight than normal processes. With
this commit, the throughput grows from ~150 MB/s to ~200 MB/s on a
PLEXTOR PX-256M5 SSD. This is the same peak throughput reached by any
of the other I/O schedulers. As such, this is also likely to be the
maximum possible throughput reachable with this workload on this
device, because I/O is mostly random, and the other schedulers
basically just pass I/O requests to the drive as fast as possible.
[1] https://github.com/Algodev-github/S
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Francesco Pollicino <fra.fra.800@gmail.com>
Signed-off-by: Alessio Masola <alessio.masola@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The processes associated with a bfq_queue, say Q, may happen to
generate their cumulative I/O at a lower rate than the rate at which
the device could serve the same I/O. This is rather probable, e.g., if
only one process is associated with Q and the device is an SSD. It
results in Q becoming often empty while in service. If BFQ is not
allowed to switch to another queue when Q becomes empty, then, during
the service of Q, there will be frequent "service holes", i.e., time
intervals during which Q gets empty and the device can only consume
the I/O already queued in its hardware queues. This easily causes
considerable losses of throughput.
To counter this problem, BFQ implements a request injection mechanism,
which tries to fill the above service holes with I/O requests taken
from other bfq_queues. The hard part in this mechanism is finding the
right amount of I/O to inject, so as to both boost throughput and not
break Q's bandwidth and latency guarantees. To this goal, the current
version of this mechanism measures the bandwidth enjoyed by Q while it
is being served, and tries to inject the maximum possible amount of
extra service that does not cause Q's bandwidth to decrease too
much.
This solution has an important shortcoming. For bandwidth measurements
to be stable and reliable, Q must remain in service for a much longer
time than that needed to serve a single I/O request. Unfortunately,
this does not hold with many workloads. This commit addresses this
issue by changing the way the amount of injection allowed is
dynamically computed. It tunes injection as a function of the service
times of single I/O requests of Q, instead of Q's
bandwidth. Single-request service times are evidently meaningful even
if Q gets very few I/O requests completed while it is in service.
As a testbed for this new solution, we measured the throughput reached
by BFQ for one of the nastiest workloads and configurations for this
scheduler: the workload generated by the dbench test (in the Phoronix
suite), with 6 clients, on a filesystem with journaling, and with the
journaling daemon enjoying a higher weight than normal processes.
With this commit, the throughput grows from ~100 MB/s to ~150 MB/s on
a PLEXTOR PX-256M5.
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Francesco Pollicino <fra.fra.800@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In most cases, it is detrimental for throughput to plug I/O dispatch
when the in-service bfq_queue becomes temporarily empty (plugging is
performed to wait for the possible arrival, soon, of new I/O from the
in-service queue). There is however a case where plugging is needed
for service guarantees. If a bfq_queue, say Q, has a higher weight
than some other active bfq_queue, and is sync, i.e., contains sync
I/O, then, to guarantee that Q does receive a higher share of the
throughput than other lower-weight queues, it is necessary to plug I/O
dispatch when Q remains temporarily empty while being served.
For this reason, BFQ performs I/O plugging when some active bfq_queue
has a higher weight than some other active bfq_queue. But this is
unnecessarily overkill. In fact, if the in-service bfq_queue actually
has a weight lower than or equal to the other queues, then the queue
*must not* be guaranteed a higher share of the throughput than the
other queues. So, not plugging I/O cannot cause any harm to the
queue. And can boost throughput.
Taking advantage of this fact, this commit does not plug I/O for sync
bfq_queues with a weight lower than or equal to the weights of the
other queues. Here is an example of the resulting throughput boost
with the dbench workload, which is particularly nasty for BFQ. With
the dbench test in the Phoronix suite, BFQ reaches its lowest total
throughput with 6 clients on a filesystem with journaling, in case the
journaling daemon has a higher weight than normal processes. Before
this commit, the total throughput was ~80 MB/sec on a PLEXTOR PX-256M5,
after this commit it is ~100 MB/sec.
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If a sync bfq_queue has a higher weight than some other queue, and
remains temporarily empty while in service, then, to preserve the
bandwidth share of the queue, it is necessary to plug I/O dispatching
until a new request arrives for the queue. In addition, a timeout
needs to be set, to avoid waiting for ever if the process associated
with the queue has actually finished its I/O.
Even with the above timeout, the device is however not fed with new
I/O for a while, if the process has finished its I/O. If this happens
often, then throughput drops and latencies grow. For this reason, the
timeout is kept rather low: 8 ms is the current default.
Unfortunately, such a low value may cause, on the opposite end, a
violation of bandwidth guarantees for a process that happens to issue
new I/O too late. The higher the system load, the higher the
probability that this happens to some process. This is a problem in
scenarios where service guarantees matter more than throughput. One
important case are weight-raised queues, which need to be granted a
very high fraction of the bandwidth.
To address this issue, this commit lower-bounds the plugging timeout
for weight-raised queues to 20 ms. This simple change provides
relevant benefits. For example, on a PLEXTOR PX-256M5S, with which
gnome-terminal starts in 0.6 seconds if there is no other I/O in
progress, the same applications starts in
- 0.8 seconds, instead of 1.2 seconds, if ten files are being read
sequentially in parallel
- 1 second, instead of 2 seconds, if, in parallel, five files are
being read sequentially, and five more files are being written
sequentially
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have a new Dell laptop which has the synaptics I2C touchpad
(06cb:7e7e) on it. After booting up the Linux, the touchpad doesn't
work, there is no interrupt when touching the touchpad, after
disable the runtime PM, everything works well.
I also tried the quirk of I2C_HID_QUIRK_DELAY_AFTER_SLEEP, it is
better after applied this quirk, there are interrupts but data it
reports is invalid.
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
For multiple dimensional arrays like below,
int a[2][3]
both llvm and pahole generated one BTF_KIND_ARRAY type like
. element_type: int
. index_type: unsigned int
. number of elements: 6
Such a collapsed BTF_KIND_ARRAY type will cause the divergence
in BTF vs. the user code. In the compile-once-run-everywhere
project, the header file is generated from BTF and used for bpf
program, and the definition in the header file will be different
from what user expects.
But the kernel actually supports chained multi-dimensional array
types properly. The above "int a[2][3]" can be represented as
Type #n:
. element_type: int
. index_type: unsigned int
. number of elements: 3
Type #(n+1):
. element_type: type #n
. index_type: unsigned int
. number of elements: 2
The following llvm commit
https://reviews.llvm.org/rL357215
also enables llvm to generated proper chained multi-dimensional arrays.
The test_btf already has a raw test ("struct test #1") for chained
multi-dimensional arrays. This patch added amended bpffs test for
chained multi-dimensional arrays.
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
According to hidpp20_batterylevel_get_battery_info my Logitech K270
keyboard reports only 2 battery levels. This matches with what I've seen
after testing with batteries at varying level of fullness, it always
reports either 5% or 30%.
Windows reports "battery good" for the 30% level. I've captured an USB
trace of Windows reading the battery and it is getting the same info
as the Linux hidpp code gets.
Now that Linux handles these devices as hidpp devices, it reports the
battery as being low as it treats anything under 31% as low, this leads
to the user constantly getting a "Keyboard battery is low" warning from
GNOME3, which is very annoying.
This commit fixes this by changing the low threshold to anything under
30%, which I assume is what Windows does.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Remove the hidpp_is_connected() function wrapper, and have the callers
directly call hidpp_root_get_protocol_version() instead.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Simply always print the HID++ version on hidpp_root_get_protocol_version
success.
This also fixes the version not being printed when a HID++ device
connected through a receiver is already connected when the hidpp driver
is loaded.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Add pin definitions for UART2 PB pins. These are used on TBS-A711
tablet.
Signed-off-by: Ondrej Jirman <megous@megous.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
A711 tablet has BMA250 accelerometer connected to I2C1 bus. Enable
both the I2C1 bus and add the accelerometer device to it.
Signed-off-by: Ondrej Jirman <megous@megous.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Both the BP[0-2] bits and the TBPROT bit are supported on this chip.
Tested and verified on a Cypress s25fl512s.
Signed-off-by: Jonas Bonn <jonas@norrbonn.se>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
It was observed that reads crossing 4K address boundary are failing.
This limitation is mentioned in Intel documents:
Intel(R) 9 Series Chipset Family Platform Controller Hub (PCH) Datasheet:
"5.26.3 Flash Access
Program Register Access:
* Program Register Accesses are not allowed to cross a 4 KB boundary..."
Enhanced Serial Peripheral Interface (eSPI)
Interface Base Specification (for Client and Server Platforms):
"5.1.4 Address
For other memory transactions, the address may start or end at any byte
boundary. However, the address and payload length combination must not
cross the naturally aligned address boundary of the corresponding Maximum
Payload Size. It must not cross a 4 KB address boundary."
Avoid this by splitting an operation crossing the boundary into two
operations.
Fixes: 8afda8b26d ("spi-nor: Add support for Intel SPI serial flash controller")
Cc: stable@vger.kernel.org
Reported-by: Romain Porte <romain.porte@nokia.com>
Tested-by: Pascal Fabreges <pascal.fabreges@nokia.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
