| Age | Commit message (Collapse) | Author |
|---|
|
skb_network_protocol() already accounts for multiple vlan
headers that may be present in the skb. However, skb_mac_gso_segment()
doesn't know anything about it and assumes that skb->mac_len
is set correctly to skip all mac headers. That may not
always be the case. If we are simply forwarding the packet (via
bridge or macvtap), all vlan headers may not be accounted for.
A simple solution is to allow skb_network_protocol to return
the vlan depth it has calculated. This way skb_mac_gso_segment
will correctly skip all mac headers.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
bt->width should be (bt)->width, and same for the other fields.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: stable@vger.kernel.org # For 3.12 or upper
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
|
|
addrconf_join_solict and addrconf_join_anycast may cause actions which
need rtnl locked, especially on first address creation.
A new DAD state is introduced which defers processing of the initial
DAD processing into a workqueue.
To get rtnl lock we need to push the code paths which depend on those
calls up to workqueues, specifically addrconf_verify and the DAD
processing.
(v2)
addrconf_dad_failure needs to be queued up to the workqueue, too. This
patch introduces a new DAD state and stop the DAD processing in the
workqueue (this is because of the possible ipv6_del_addr processing
which removes the solicited multicast address from the device).
addrconf_verify_lock is removed, too. After the transition it is not
needed any more.
As we are not processing in bottom half anymore we need to be a bit more
careful about disabling bottom half out when we lock spin_locks which are also
used in bh.
Relevant backtrace:
[ 541.030090] RTNL: assertion failed at net/core/dev.c (4496)
[ 541.031143] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.33-1-amd64-vyatta #1
[ 541.031145] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[ 541.031146] ffffffff8148a9f0 000000000000002f ffffffff813c98c1 ffff88007c4451f8
[ 541.031148] 0000000000000000 0000000000000000 ffffffff813d3540 ffff88007fc03d18
[ 541.031150] 0000880000000006 ffff88007c445000 ffffffffa0194160 0000000000000000
[ 541.031152] Call Trace:
[ 541.031153] <IRQ> [<ffffffff8148a9f0>] ? dump_stack+0xd/0x17
[ 541.031180] [<ffffffff813c98c1>] ? __dev_set_promiscuity+0x101/0x180
[ 541.031183] [<ffffffff813d3540>] ? __hw_addr_create_ex+0x60/0xc0
[ 541.031185] [<ffffffff813cfe1a>] ? __dev_set_rx_mode+0xaa/0xc0
[ 541.031189] [<ffffffff813d3a81>] ? __dev_mc_add+0x61/0x90
[ 541.031198] [<ffffffffa01dcf9c>] ? igmp6_group_added+0xfc/0x1a0 [ipv6]
[ 541.031208] [<ffffffff8111237b>] ? kmem_cache_alloc+0xcb/0xd0
[ 541.031212] [<ffffffffa01ddcd7>] ? ipv6_dev_mc_inc+0x267/0x300 [ipv6]
[ 541.031216] [<ffffffffa01c2fae>] ? addrconf_join_solict+0x2e/0x40 [ipv6]
[ 541.031219] [<ffffffffa01ba2e9>] ? ipv6_dev_ac_inc+0x159/0x1f0 [ipv6]
[ 541.031223] [<ffffffffa01c0772>] ? addrconf_join_anycast+0x92/0xa0 [ipv6]
[ 541.031226] [<ffffffffa01c311e>] ? __ipv6_ifa_notify+0x11e/0x1e0 [ipv6]
[ 541.031229] [<ffffffffa01c3213>] ? ipv6_ifa_notify+0x33/0x50 [ipv6]
[ 541.031233] [<ffffffffa01c36c8>] ? addrconf_dad_completed+0x28/0x100 [ipv6]
[ 541.031241] [<ffffffff81075c1d>] ? task_cputime+0x2d/0x50
[ 541.031244] [<ffffffffa01c38d6>] ? addrconf_dad_timer+0x136/0x150 [ipv6]
[ 541.031247] [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
[ 541.031255] [<ffffffff8105313a>] ? call_timer_fn.isra.22+0x2a/0x90
[ 541.031258] [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
Hunks and backtrace stolen from a patch by Stephen Hemminger.
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Dropping packets in __dev_queue_xmit() when transmit queue
is stopped (NIC TX ring buffer full or BQL limit reached) currently
outputs a syslog message.
It would be better to get a precise count of such events available in
netdevice stats so that monitoring tools can have a clue.
This extends the work done in caf586e5f23ce
("net: add a core netdev->rx_dropped counter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Add implementation for the add/del vxlan port ndo calls, using the
CONFIG_DEV firmware command.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Introduce the CONFIG_DEV firmware command which we will use to
configure the UDP port assumed by the firmware for the VXLAN offloads.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
When using the irqchip helper inside the gpiolib, make sure
the IRQs are unmapped/disposed before the irqdomain is removed
as part of removing the gpiochip.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
|
|
A function to be used to check whether a caller has put a ref object
(opened) a struct ttm_base_object
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
|
|
Allow prime fds and at the same time block legacy handles for render-nodes
in the surface reference ioctls. This means these ioctls can be used
directly from prime-aware clients, and that they can be called from
render-nodes.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
|
|
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
|
|
The master management was previously protected by the drm_device::struct_mutex.
In order to avoid locking order violations in a reworked dropped master
security check in the vmwgfx driver, break it out into a separate master_mutex.
Locking order is master_mutex -> struct_mutex.
Also remove drm_master::blocked since it's not used.
v2: Add an inline comment about what drm_device::master_mutex is protecting.
v3: Remove unneeded struct_mutex locks. Fix error returns in
drm_setmaster_ioctl().
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
|
|
It doesn't appear to be used anywhere.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
|
|
Add a drm_is_legacy() helper, constify argument to drm_is_render_client(),
and use / change helpers where appropriate.
v2: s/drm_is_legacy/drm_is_legacy_client/ and adapt to new code context.
v3: s/legacy_client/primary_client/
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
|
|
Like for render-nodes, there is no point in maintaining the master concept
for control nodes, so set the struct drm_file::master pointer to NULL.
At the same time, make sure DRM_MASTER | DRM_CONTROL_ALLOW ioctls are always
allowed when called through the control node. Previously the caller also
needed to be master.
v2: Adapt to refactoring of ioctl permission check.
v3: Formatting of logical expression. Use drm_is_control_client() instead of
drm_is_control().
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
|
|
'regmap/topic/lock', 'regmap/topic/mmio', 'regmap/topic/nodev', 'regmap/topic/parse-val' and 'regmap/topic/patch' into regmap-next
|
|
To be consistent, lets use msec for this timeout as well.
Note: This define value is a minimum scan time taken from BT Core spec 4.0,
Vol 3, Part C, chapter 9.2.6
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
With this patch it is possible to control discovery interleaved
timeout value from debugfs.
It is for fine tuning of this timeout.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
Keep msec instead of jiffies in this define. This is needed by following
patch where we want this timeout to be exposed in debugfs.
Note: Value of this timeout comes from recommendation in BT Core Spec.4.0,
Vol 3, Part C, chapter 13.2.1.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
This is always DRM_NAME, so we can just make it part of the format
string instead of asking prink to do it for us.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
In the logging code, we are currently checking is we need to output in
drm_ut_debug_printk(). This is too late. The problem is that when we write
something like:
DRM_DEBUG_DRIVER("ELD on [CONNECTOR:%d:%s], [ENCODER:%d:%s]\n",
connector->base.id,
drm_get_connector_name(connector),
connector->encoder->base.id,
drm_get_encoder_name(connector->encoder));
We start by evaluating the arguments (so call drm_get_connector_name() and
drm_get_connector_name()) before ending up in drm_ut_debug_printk() which will
then does nothing.
This means we execute a lot of instructions (drm_get_connector_name(), in turn,
calls snprintf() for example) to happily discard them in the normal case,
drm.debug=0.
So, let's put the test on drm_debug earlier, in the macros themselves.
Sprinkle an unlikely() as well for good measure.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
This macro was trying to use the non existing DRM_UT_MODE debug category
and looks like it should be covered by DRM_LOG_KMS().
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
That comment wasn't super-readable, so I tried to improve it:
- Put the comment before the values it's documenting
- Add a mention to PRIME
- Reword things a bit to be a lighter read
- Add a note about the option to set the debug value at run-time
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
Introduce dm_table_run_md_queue_async() to run the request_queue of the
mapped_device associated with a request-based DM table.
Also add dm_md_get_queue() wrapper to extract the request_queue from a
mapped_device.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
|
|
Remove dm_get_mapinfo() because no target uses it. Targets can allocate
per-bio data using ti->per_bio_data_size, this is much more flexible
than union map_info.
Leave union map_info only for the request-based multipath target's use.
Also delete the unused "unsigned long long ll" field of union map_info.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
|
|
skb_zerocopy can copy elements of the frags array between skbs, but it doesn't
orphan them. Also, it doesn't handle errors, so this patch takes care of that
as well, and modify the callers accordingly. skb_tx_error() is also added to
the callers so they will signal the failed delivery towards the creator of the
skb.
Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
If an IPv6 host route with metrics exists, an attempt to add a
new route for the same target with different metrics fails but
rewrites the metrics anyway:
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1000
12sp0:~ # ip -6 route show
fe80::/64 dev eth0 proto kernel metric 256
fec0::1 dev eth0 metric 1024 rto_min lock 1s
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1500
RTNETLINK answers: File exists
12sp0:~ # ip -6 route show
fe80::/64 dev eth0 proto kernel metric 256
fec0::1 dev eth0 metric 1024 rto_min lock 1.5s
This is caused by all IPv6 host routes using the metrics in
their inetpeer (or the shared default). This also holds for the
new route created in ip6_route_add() which shares the metrics
with the already existing route and thus ip6_route_add()
rewrites the metrics even if the new route ends up not being
used at all.
Another problem is that old metrics in inetpeer can reappear
unexpectedly for a new route, e.g.
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1000
12sp0:~ # ip route del fec0::1
12sp0:~ # ip route add fec0::1 dev eth0
12sp0:~ # ip route change fec0::1 dev eth0 hoplimit 10
12sp0:~ # ip -6 route show
fe80::/64 dev eth0 proto kernel metric 256
fec0::1 dev eth0 metric 1024 hoplimit 10 rto_min lock 1s
Resolve the first problem by moving the setting of metrics down
into fib6_add_rt2node() to the point we are sure we are
inserting the new route into the tree. Second problem is
addressed by introducing new flag DST_METRICS_FORCE_OVERWRITE
which is set for a new host route in ip6_route_add() and makes
ipv6_cow_metrics() always overwrite the metrics in inetpeer
(even if they are not "new"); it is reset after that.
v5: use a flag in _metrics member rather than one in flags
v4: fix a typo making a condition always true (thanks to Hannes
Frederic Sowa)
v3: rewritten based on David Miller's idea to move setting the
metrics (and allocation in non-host case) down to the point we
already know the route is to be inserted. Also rebased to
net-next as it is quite late in the cycle.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
This fixes a race which happens by freeing an object on the stack.
Quoting Julius:
> The issue is
> that it calls usbnet_terminate_urbs() before that, which temporarily
> installs a waitqueue in dev->wait in order to be able to wait on the
> tasklet to run and finish up some queues. The waiting itself looks
> okay, but the access to 'dev->wait' is totally unprotected and can
> race arbitrarily. I think in this case usbnet_bh() managed to succeed
> it's dev->wait check just before usbnet_terminate_urbs() sets it back
> to NULL. The latter then finishes and the waitqueue_t structure on its
> stack gets overwritten by other functions halfway through the
> wake_up() call in usbnet_bh().
The fix is to just not allocate the data structure on the stack.
As dev->wait is abused as a flag it also takes a runtime PM change
to fix this bug.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Reported-by: Grant Grundler <grundler@google.com>
Tested-by: Grant Grundler <grundler@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next
|
|
This allows drivers to specify the size of their per-command private
data in the host template and then get extra memory allocated for
each command instead of needing another allocation in ->queuecommand.
With the current SCSI code that already does multiple allocations for
each command this probably doesn't make a big performance impact, but
it allows to clean up the drivers, and prepare them for using the
blk-mq infrastructure where the common allocation will make a difference.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
|
|
We don't use the passed in scsi command for anything, so just add a adapter-
wide internal status to go along with the internal scb that is used unter
int_mtx to pass back the return value and get rid of all the complexities
and abuse of the scsi_cmnd structure.
This gets rid of the only user of scsi_allocate_command/scsi_free_command,
which can now be removed.
[jejb: checkpatch fixes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Adam Radford <aradford@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
|
|
EVPD page 0x83 is used to uniquely identify the device.
So instead of having each and every program issue a separate
SG_IO call to retrieve this information it does make far more
sense to display it in sysfs.
Some older devices (most notably tapes) will only report reliable
information in page 0x80 (Unit Serial Number). So export this
in the sysfs attribute 'vpd_pg80'.
[jejb: checkpatch fix]
[hare: attach after transport configure]
[fengguang.wu@intel.com: spotted problems with the original now fixed]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
|
|
next/cleanup2
Merge "arm: Xilinx Zynq cleanup patches for v3.15" from Michal Simek:
- Redesign SLCR initialization to enable
driver developing which targets SLCR space
* tag 'zynq-cleanup-for-3.15-v2' of git://git.xilinx.com/linux-xlnx:
ARM: zynq: Add waituart implementation
ARM: zynq: Move of_clk_init from clock driver
ARM: zynq: Introduce zynq_slcr_unlock()
ARM: zynq: Add and use zynq_slcr_read/write() helper functions
ARM: zynq: Make zynq_slcr_base static
ARM: zynq: Map I/O memory on clkc init
ARM: zynq: Hang iomapped slcr address on device_node
ARM: zynq: Split slcr in two parts
ARM: zynq: Move clock_init from slcr to common
arm: dt: zynq: Add fclk-enable property to clkc node
[Arnd: remove SOC_BUS support from pull request]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
into next/drivers
Merge "reset controller fixes and updates" from Philipp Zabel:
* 'reset/for_v3.15' of git://git.pengutronix.de/git/pza/linux:
reset: Add optional resets and stubs
reset: Add of_reset_control_get
reset: Mark function as static and remove unused function in core.c
reset: allow drivers to request probe deferral
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
This patch adds support for Samsung 10Gb ethernet driver(sxgbe).
- sxgbe core initialization
- Tx and Rx support
- MDIO support
- ISRs for Tx and Rx
- ifconfig support to driver
Signed-off-by: Siva Reddy Kallam <siva.kallam@samsung.com>
Signed-off-by: Vipul Pandya <vipul.pandya@samsung.com>
Signed-off-by: Girish K S <ks.giri@samsung.com>
Neatening-by: Joe Perches <joe@perches.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The vlan support 2 proto: 802.1q and 802.1ad, so make a new function
called vlan_dev_vlan_proto() which could return the vlan proto for
input dev.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The packet hash can be considered a property of the packet, not just
on RX path.
This patch changes name of rxhash and l4_rxhash skbuff fields to be
hash and l4_hash respectively. This includes changing uses of the
field in the code which don't call the access functions.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
'regulator/topic/st-pwm', 'regulator/topic/ti-abb', 'regulator/topic/tps51632', 'regulator/topic/tps62360', 'regulator/topic/tps6507x', 'regulator/topic/tps65090' and 'regulator/topic/tps65217' into regulator-next
|
|
'regulator/topic/max8997', 'regulator/topic/max8998', 'regulator/topic/mc13xxx', 'regulator/topic/pfuze100', 'regulator/topic/rc5t583' and 'regulator/topic/s2mps11' into regulator-next
|
|
'regulator/topic/enable', 'regulator/topic/fan53555', 'regulator/topic/fixed', 'regulator/topic/gpio', 'regulator/topic/lp3971', 'regulator/topic/lp872x' and 'regulator/topic/max14577' into regulator-next
|
|
Especially in crowded environments it can become frequent that we have
to send out whatever pending event there is stored. Since user space
has its own filtering of small RSSI changes sending a 0 value will
essentially force user space to wake up the higher layers (e.g. over
D-Bus) even though the RSSI didn't actually change more than the
threshold value.
This patch adds storing also of the RSSI for pending advertising reports
so that we report an as accurate RSSI as possible when we have to send
out the stored information to user space.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
The line was incorrectly split between the variable type and its name.
This patch fixes the issue.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
To avoid too many events being sent to user space and to help parsing of
all available remote device data it makes sense for us to wait for the
scan response and send a single merged Device Found event to user space.
This patch adds a few new variables to hci_dev to track the last
received ADV_IND/ADV_SCAN_IND, i.e. those which will cause a SCAN_REQ to
be send in the case of active scanning. When the SCAN_RSP is received
the pending data is passed together with the SCAN_RSP to the
mgmt_device_found function which takes care of merging them into a
single Device Found event.
We also need a bit of extra logic to handle situations where we don't
receive a SCAN_RSP after caching some data. In such a scenario we simply
have to send out the pending data as it is and then operate on the new
report as if there was no pending data.
We also need to send out any pending data when scanning stops as
well as ensure that the storage is empty at the start of a new active
scanning session. These both cases are covered by the update to the
hci_cc_le_set_scan_enable function in this patch.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
When we're in peripheral mode (HCI_ADVERTISING flag is set) the most
natural mapping of connect() is to perform directed advertising to the
peer device.
This patch does the necessary changes to enable directed advertising and
keeps the hci_conn state as BT_CONNECT in a similar way as is done for
central or BR/EDR connection initiation.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
In preparation for being able to merge ADV_IND/ADV_SCAN_IND and SCAN_RSP
together into a single device found event add a second parameter to the
mgmt_device_found function. For now all callers pass NULL as this
parameters since we don't yet have storing of the last received
advertising report.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
|
|
cpufreq_notify_transition() and cpufreq_notify_post_transition() shouldn't be
called directly by cpufreq drivers anymore and so these should be marked static.
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
Whenever we change the frequency of a CPU, we call the PRECHANGE and POSTCHANGE
notifiers. They must be serialized, i.e. PRECHANGE and POSTCHANGE notifiers
should strictly alternate, thereby preventing two different sets of PRECHANGE or
POSTCHANGE notifiers from interleaving arbitrarily.
The following examples illustrate why this is important:
Scenario 1:
-----------
A thread reading the value of cpuinfo_cur_freq, will call
__cpufreq_cpu_get()->cpufreq_out_of_sync()->cpufreq_notify_transition()
The ondemand governor can decide to change the frequency of the CPU at the same
time and hence it can end up sending the notifications via ->target().
If the notifiers are not serialized, the following sequence can occur:
- PRECHANGE Notification for freq A (from cpuinfo_cur_freq)
- PRECHANGE Notification for freq B (from target())
- Freq changed by target() to B
- POSTCHANGE Notification for freq B
- POSTCHANGE Notification for freq A
We can see from the above that the last POSTCHANGE Notification happens for freq
A but the hardware is set to run at freq B.
Where would we break then?: adjust_jiffies() in cpufreq.c & cpufreq_callback()
in arch/arm/kernel/smp.c (which also adjusts the jiffies). All the
loops_per_jiffy calculations will get messed up.
Scenario 2:
-----------
The governor calls __cpufreq_driver_target() to change the frequency. At the
same time, if we change scaling_{min|max}_freq from sysfs, it will end up
calling the governor's CPUFREQ_GOV_LIMITS notification, which will also call
__cpufreq_driver_target(). And hence we end up issuing concurrent calls to
->target().
Typically, platforms have the following logic in their ->target() routines:
(Eg: cpufreq-cpu0, omap, exynos, etc)
A. If new freq is more than old: Increase voltage
B. Change freq
C. If new freq is less than old: decrease voltage
Now, if the two concurrent calls to ->target() are X and Y, where X is trying to
increase the freq and Y is trying to decrease it, we get the following race
condition:
X.A: voltage gets increased for larger freq
Y.A: nothing happens
Y.B: freq gets decreased
Y.C: voltage gets decreased
X.B: freq gets increased
X.C: nothing happens
Thus we can end up setting a freq which is not supported by the voltage we have
set. That will probably make the clock to the CPU unstable and the system might
not work properly anymore.
This patch introduces a set of synchronization primitives to serialize frequency
transitions, which are to be used as shown below:
cpufreq_freq_transition_begin();
//Perform the frequency change
cpufreq_freq_transition_end();
The _begin() call sends the PRECHANGE notification whereas the _end() call sends
the POSTCHANGE notification. Also, all the necessary synchronization is handled
within these calls. In particular, even drivers which set the ASYNC_NOTIFICATION
flag can also use these APIs for performing frequency transitions (ie., you can
call _begin() from one task, and call the corresponding _end() from a different
task).
The actual synchronization underneath is not that complicated:
The key challenge is to allow drivers to begin the transition from one thread
and end it in a completely different thread (this is to enable drivers that do
asynchronous POSTCHANGE notification from bottom-halves, to also use the same
interface).
To achieve this, a 'transition_ongoing' flag, a 'transition_lock' spinlock and a
wait-queue are added per-policy. The flag and the wait-queue are used in
conjunction to create an "uninterrupted flow" from _begin() to _end(). The
spinlock is used to ensure that only one such "flow" is in flight at any given
time. Put together, this provides us all the necessary synchronization.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
This change adds support to automatically mark a control method as
"serialized" if the method creates any named objects. This will
positively prevent the method from being entered by more than one
thread and thus preventing a possible abort when an attempt is
made to create an object twice.
Implemented by parsing all non-serialize control methods at table
load time.
This feature is disabled by default and this patch also adds a new
Linux kernel parameter "acpi_auto_serialize" to allow this feature
to be turned on for a specific boot.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
According to the reports, the "acpi_serialize" mechanism is broken as:
A. The parallel method calls can still happen when the interpreter lock is
released under the following conditions:
1. External callbacks are invoked, for example, by the region handlers,
the exception handlers, etc.;
2. Module level execution is performed when Load/LoadTable opcodes are
executed, and
3. The _REG control methods are invoked to complete the region
registrations.
B. For the following situations, the interpreter lock need to be released
even for a serialized method while currently, the lock-releasing
operation is marked as a no-op by
acpi_ex_relinquish/reacquire_interpreter() when this mechanism is
enabled:
1. Wait opcode is executed,
2. Acquire opcode is executed, and
3. Sleep opcode is executed.
This patch removes this mechanism and the internal
acpi_ex_relinquish/reacquire_interpreter() APIs. Lv Zheng.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
This provides a function gpiochip_irqchip_add() to set
up an irqchip for a GPIO controller, and a function
gpiochip_set_chained_irqchip() to chain it to a parent
irqchip.
Most GPIOs are of the type where a number of lines form
a cascaded interrupt controller chained onto
the primary system interrupt controller (or further down the
chain) so let's add this helper and factor the code to
request the lines to be used as IRQs, the .to_irq() function
and the irqdomain into the core as well.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
|
