This patch adds support for creating a queuing context outside
of the queue itself. This enables us to batch up pieces of IO
before grabbing the block device queue lock and submitting them to
the IO scheduler.
The context is created on the stack of the process and assigned in
the task structure, so that we can auto-unplug it if we hit a schedule
event.
The current queue plugging happens implicitly if IO is submitted to
an empty device, yet callers have to remember to unplug that IO when
they are going to wait for it. This is an ugly API and has caused bugs
in the past. Additionally, it requires hacks in the vm (->sync_page()
callback) to handle that logic. By switching to an explicit plugging
scheme we make the API a lot nicer and can get rid of the ->sync_page()
hack in the vm.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
It was always abuse to reuse the plugging infrastructure for this,
convert it to the (new) real API for delaying queueing a bit. A
default delay of 3 msec is defined, to match the previous
behaviour.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
It was always abuse to reuse the plugging infrastructure for this,
convert it to the (new) real API for delaying queueing a bit.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Acked-by: David S. Miller <davem@davemloft.net>
This fixes a particular nasty racing problem found when using
Xen hypervisor with the console (hvc) output being routed to the
serial port and the serial port receiving data when
probe_irq_off(probe_irq_on) is running.
Specifically the bug manifests itself with:
[ 4.470693] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[ 4.470693] IP: [<ffffffff810a8c65>] handle_IRQ_event+0xe/0xc9
..snip..
[ 4.470693] Call Trace:
[ 4.470693] <IRQ>
[ 4.470693] [<ffffffff810aa645>] handle_percpu_irq+0x3c/0x69
[ 4.470693] [<ffffffff8123cda7>] __xen_evtchn_do_upcall+0xfd/0x195
[ 4.470693] [<ffffffff810308cf>] ? xen_restore_fl_direct_end+0x0/0x1
[ 4.470693] [<ffffffff8123d873>] xen_evtchn_do_upcall+0x32/0x47
[ 4.470693] [<ffffffff81034dfe>] xen_do_hypervisor_callback+0x1e/0x30
[ 4.470693] <EOI>
[ 4.470693] [<ffffffff8100922a>] ? hypercall_page+0x22a/0x1000
[ 4.470693] [<ffffffff8100922a>] ? hypercall_page+0x22a/0x1000
[ 4.470693] [<ffffffff810301c5>] ? xen_force_evtchn_callback+0xd/0xf
[ 4.470693] [<ffffffff810308e2>] ? check_events+0x12/0x20
[ 4.470693] [<ffffffff81030889>] ? xen_irq_enable_direct_end+0x0/0x7
[ 4.470693] [<ffffffff810ab0a0>] ? probe_irq_on+0x8f/0x1d7
[ 4.470693] [<ffffffff812b105e>] ? serial8250_config_port+0x7b7/0x9e6
[ 4.470693] [<ffffffff812ad66c>] ? uart_add_one_port+0x11b/0x305
The bug is trigged by three actors working together:
A). serial_8250_config_port calling
probe_irq_off(probe_irq_on())
wherein all of the IRQ handlers are being started and shut off.
The functions utilize the sleep functions so the minimum time
they are run is 120 msec.
B). Xen hypervisor receiving on the serial line any character and
setting the bits in the event channel - during this 120 msec timeframe.
C). The hvc API makes a call to 'request_irq' (and hence setting desc->action
to a valid value), much much later - when user space opens
/dev/console (hvc_open). To make the console usable during bootup,
the Xen HVC implementation sets the IRQ chip (and correspondingly
the event channel) much earlier. The IRQ chip handler that is used
is the handle_percpu_irq (aaca49642b)
Back to the issue. When A) is being called it ends up calling the
xen_percpu_chip's chip->startup twice and chip->shutdown once. Those
are set to the default_startup and mask_irq (events.c) respectivly.
If (and this seems to depend on what serial concentrator you use), B)
gets data from the serial port it sets in the event channel a pending bit.
When A) calls chip->startup(), the masking of the pending bit, and
unmasking of the event channel mask, and also setting of the upcall_pending
flag is done (since there is data present on the event channel).
If before the 120 msec has elapsed, any IRQ handler (Xen IRQ has one
IRQ handler, which checks the event channels bitmap to figure which one
to call) is called we end up calling the handle_percpu_irq. The
handle_percpu_irq calls desc->action (which is NULL) and we blow up.
Caveats: I could only reproduce this on 2.6.32 pvops. I am not sure
why this is not showing up on 2.6.38 kernel.
The probe_irq_on/off has code to disable poking specific IRQ lines. This is
done by using the set_irq_noprobe() and then we do not have to
worry about the handle_percpu_irq being called before the IRQ action
handler has been installed.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Like in commit 44713b67db
("ipv4: Optimize flow initialization in output route lookup."
we can optimize the on-stack flow setup to only initialize
the members which are actually used.
Otherwise we bzero the entire structure, then initialize
explicitly the first half of it.
Signed-off-by: David S. Miller <davem@davemloft.net>
Like in commit 44713b67db
("ipv4: Optimize flow initialization in output route lookup."
we can optimize the on-stack flow setup to only initialize
the members which are actually used.
Otherwise we bzero the entire structure, then initialize
explicitly the first half of it.
Signed-off-by: David S. Miller <davem@davemloft.net>
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=29252
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=30462
In commit d80bc0fd26 ("ipv6: Always
clone offlink routes.") we forced the kernel to always clone offlink
routes.
The reason we do that is to make sure we never bind an inetpeer to a
prefixed route.
The logic turned on here has existed in the tree for many years,
but was always off due to a protecting CPP define. So perhaps
it's no surprise that there is a logic bug here.
The problem is that we canot clone a route that is already a
host route (ie. has DST_HOST set). Because if we do, an identical
entry already exists in the routing tree and therefore the
ip6_rt_ins() call is going to fail.
This sets off a series of failures and high cpu usage, because when
ip6_rt_ins() fails we loop retrying this operation a few times in
order to handle a race between two threads trying to clone and insert
the same host route at the same time.
Fix this by simply using the route as-is when DST_HOST is set.
Reported-by: slash@ac.auone-net.jp
Reported-by: Ernst Sjöstrand <ernstp@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
"After merging the nfsd tree, today's linux-next build (powerpc
ppc64_defconfig) produced this warning:
net/sunrpc/svcauth_unix.c: In function 'unix_domain_find':
net/sunrpc/svcauth_unix.c:58: warning: passing argument 1 of
+'svcauth_unix_domain_release' from incompatible pointer type
net/sunrpc/svcauth_unix.c:41: note: expected 'struct auth_domain *' but
argument
+is of type 'struct unix_domain *'
Introduced by commit 8b3e07ac90 ("svcrpc: fix rare race on unix_domain
creation")."
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The only time when granted pages need to be treated specially is when
using Xen's PTE modification for grant mappings owned by another domain
(that is, only gntdev on PV guests). Otherwise, the area does not
require VM_DONTCOPY and VM_PFNMAP, since it can be accessed just like
any other page of RAM.
Since the vm_operations_struct close operations decrement reference
counts, a corresponding open function that increments them is required
now that it is possible to have multiple references to a single area.
We are careful in the gntdev to check if we can remove those flags. The
reason that we need to be careful in gntdev on PV guests is because we are
not changing the PFN/MFN mapping on PV; instead, we change the application's
page tables to point to the other domain's memory. This means that the vma
cannot be copied without using another grant mapping hypercall; it also
requires special handling on unmap, which is the reason for gntdev's
dependency on the MMU notifier.
For gntalloc, this is not a concern - the pages are owned by the domain
using the gntalloc device, and can be mapped and unmapped in the same manner
as any other page of memory.
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Added in git commit "We are.." from email correspondence]
Add Rajendra Nayak and myself as maintainers for the OMAP
powerdomain/clockdomain per-SoC layer code.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Benoît Cousson <b-cousson@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
if building kernels without OMAP2 support, we
will see a warning such as:
arch/arm/mach-omap2/io.c: In function 'omap2_init_common_infrastructure':
arch/arm/mach-omap2/io.c:389:3: warning: statement with no effect
arch/arm/mach-omap2/io.c:391:3: warning: statement with no effect
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
addr is actually a virtual address so use an unsigned long. Fixes:
CC drivers/xen/gntdev.o
drivers/xen/gntdev.c: In function 'map_grant_pages':
drivers/xen/gntdev.c:268: warning: cast from pointer to integer of different size
Reduce the scope of the variable at the same time.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The caller will not undo a mapping which failed and therefore the
override will not be removed.
This is especially bad in the case of GNTMAP_contains_pte mapping type
mappings where m2p_add_override will destroy the kernel mapping of the
page.
This was observed via a failure of map_grant_pages in gntdev_mmap (due
to userspace using a bad grant reference), which left the page in
question unmapped (because it was a GNTMAP_contains_pte mapping) which
led to a crash later on.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/pseries: Disable VPNH feature
powerpc/iseries: Fix early init access to lppaca
Fixes this build-check error:
include/linux/sysctl.h:28: included file 'linux/rcupdate.h' is not exported
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
omap_sr_probe() creates the smartreflex debug directory and its
underlying nvalue debug directory. These directories are removed in
omap_sr_remove().
Basic smartreflex functionality tested on OMAP3630 Zoom3 & OMAP4430 SDP
Signed-off-by: Anand S Sawant <sawant@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
* Build unconditionally as ARM for correct interoperation with
OMAP firmware.
* Fix an out-of-range ADR when building for ARM.
* Remove deprecated PC-relative stores.
* Add the required ENDPROC() directive for each ENTRY().
* .align before data words.
* Handle non-interworking return from v7_flush_dcache_all.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Kevin Hilman <khilman@ti.com>
* Build unconditionally as ARM for correct interoperation with
OMAP firmware.
* Remove deprecated PC-relative stores
* Add the required ENDPROC() directive for each ENTRY().
* .align before data words
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
For various reasons, Linux now only officially supports being built
with tools which are new enough to understand the SMC instruction.
Replacing the hand-encoded instructions when the mnemonic also
allows for correct assembly in Thumb-2 (otherwise, the result is
random data in the middle of the code).
The Makefile already ensures that this file is built with a high
enough gcc -march= flag (armv7-a).
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Code marked with ENTRY() also needs a matching ENDPROC() directive,
in order to ensure that the type and instruction set of the
symbol are correctly annotated.
ENDPROC() tags the affected symbol as a function symbol, which will
ensure that link-time fixups don't accidentally switch to the
wrong instruction set.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
For CONFIG_THUMB2_KERNEL, the existing definition of do_wfi() will
insert invalid code into the instruction stream.
Any assembler which can assemble Thumb-2 is guaranteed to accept
the "wfi" mnemonic, so for the Thumb-2 case, just use the mnemonic.
The ARM case is left as-is.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Kevin Hilman <khilman@ti.com>
IVA device is not present in many OMAP3 variants.
This patch ensures that initialization is tied to
the presence of IVA on the device.
Signed-off-by: Sanjeev Premi <premi@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Voltage control on TWL can be done using VMODE/I2C1/I2C_SR.
Since almost all platforms use I2C_SR on omap3, omap3_twl_init by
default expects that OMAP's I2C_SR is plugged in to TWL's I2C
and calls omap3_twl_set_sr_bit. On platforms where I2C_SR is not connected,
the board files are expected to call omap3_twl_set_sr_bit(false) to
ensure that I2C_SR path is not set for voltage control and prevent
the default behavior of omap3_twl_init.
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Thara Gopinath <thara@ti.com>
Signed-off-by: Shweta Gulati <shweta.gulati@ti.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Kevin Hilman <khilman@ti.com>
Add a description field to each idle C-state. This helps to give
better data with PowerTop and one don't have to refer to the code
to link what Cx means from system point of view while analysing
PowerTop data.
No functional change.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Remove the custom restore_control_register() and use the exported
set_cr() instead to set the system control register(SCTRL) value.
No functional change.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
The OMAP2 and OMAP3 PM code clears clockdomain wakeup and sleep
dependencies. This is unnecessary after commit
6f7f63cc9a ("OMAP clockdomain:
initialize clockdomain registers when the clockdomain layer starts")
which clears these dependencies during clockdomain init.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Now that omap_hwmod + omap_device is used for OMAP UART device and
driver code, we no longer need the UART physical addresses in
omap_globals.
Note that the #defines for the base addresses are still left in
<plat/serial.h> since they are used by DEBUG_LL and uncompress code.
Build tested for OMAP1 (omap1_defconfig) and OMAP2+ (omap2plus_defconfig)
Signed-off-by: Kevin Hilman <khilman@ti.com>
kzalloc() may fail, if so return -ENOMEM. Also Walter Harms suggested
to use kasprintf() instead of kzalloc+strcpy+strcat.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
OMP3630 silicon can enable higher frequencies only depending on the board
characteristics meeting the recommended standards, and has to be selectively
toggled.
Beagle XM uses 3730 variant and the board design allows enabling 800MHz and
1GHz OPPs. However, We need Smart reflex class 1.5 and ABB to enable 1GHz
safely. For the moment, we tweak the default table to allow for 800Mhz OPP
usage.
Reported-by: Koen Kooi <koen@beagleboard.org>
Tested-by: Koen Kooi <koen@beagleboard.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
omap3 and omap4 opp_init should be made non-static to allow
for platform specific opp table tweaking. making these static
conflicts with the definition in pm.h(global) as well.
we include pm.h as well to ensure that there are no such prototype
conflicts with actual implementation in the future.
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
In case in user has a OMAP3630 < ES1.2 the kernel should warn the user
about the ERRATUM, but using pr_warn instead of WARN_ON is already
enough, as there is nothing else the user can do besides changing the
board.
Signed-off-by: Ricardo Salveti de Araujo <ricardo.salveti@canonical.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
debug code in TI-ST driver can be enabled by #defining
DEBUG in the first line of the code and in case debugfs
is mounted, the 2 entries in /sys/kernel/debug/ti-st/ will
also provide useful information.
These 2 were broken because of the recent changes to the parsing
logic and the registration mechanism of the protocol drivers,
this patch fixes them.
Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
