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425173 commits

Author SHA1 Message Date
Jingoo Han
7c815c59c0 video: nvidiafb: remove unnecessary pci_set_drvdata()
The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-01-17 10:57:39 +02:00
Jingoo Han
a1d99607c4 video: asiliantfb: remove unnecessary pci_set_drvdata()
The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-01-17 10:57:38 +02:00
Laurent Pinchart
40af1eb5a7 fbdev: sh_mobile_lcdcfb: Don't use plain 0 as NULL pointer
This fixes a sparse warning.

Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-01-17 10:57:38 +02:00
Jakob Bornecrantz
1985f99987 drm/vmwgfx: Invalidate surface on non-readback unbind
Fixes error messages in vmware.log

Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Reviewed-by: Michael Banack <banackm@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2014-01-17 09:12:26 +01:00
David S. Miller
cf84eb0b09 Merge branch 'virtio_rx_merging'
Michael Dalton says:

====================
virtio-net: mergeable rx buffer size auto-tuning

The virtio-net device currently uses aligned MTU-sized mergeable receive
packet buffers. Network throughput for workloads with large average
packet size can be improved by posting larger receive packet buffers.
However, due to SKB truesize effects, posting large (e.g, PAGE_SIZE)
buffers reduces the throughput of workloads that do not benefit from GRO
and have no large inbound packets.

This patchset introduces virtio-net mergeable buffer size auto-tuning,
with buffer sizes ranging from aligned MTU-size to PAGE_SIZE. Packet
buffer size is chosen based on a per-receive queue EWMA of incoming
packet size.

To unify mergeable receive buffer memory allocation and improve
SKB frag coalescing, all mergeable buffer memory allocation is
migrated to per-receive queue page frag allocators.

The per-receive queue mergeable packet buffer size is exported via
sysfs, and the network device sysfs layer has been extended to add
support for device-specific per-receive queue sysfs attribute groups.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:17 -08:00
Michael Dalton
fbf28d78f5 virtio-net: initial rx sysfs support, export mergeable rx buffer size
Add initial support for per-rx queue sysfs attributes to virtio-net. If
mergeable packet buffers are enabled, adds a read-only mergeable packet
buffer size sysfs attribute for each RX queue.

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:07 -08:00
Michael Dalton
03144b5869 lib: Ensure EWMA does not store wrong intermediate values
To ensure ewma_read() without a lock returns a valid but possibly
out of date average, modify ewma_add() by using ACCESS_ONCE to prevent
intermediate wrong values from being written to avg->internal.

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:06 -08:00
Michael Dalton
a953be53ce net-sysfs: add support for device-specific rx queue sysfs attributes
Extend existing support for netdevice receive queue sysfs attributes to
permit a device-specific attribute group. Initial use case for this
support will be to allow the virtio-net device to export per-receive
queue mergeable receive buffer size.

Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:06 -08:00
Michael Dalton
ab7db91705 virtio-net: auto-tune mergeable rx buffer size for improved performance
Commit 2613af0ed1 ("virtio_net: migrate mergeable rx buffers to page frag
allocators") changed the mergeable receive buffer size from PAGE_SIZE to
MTU-size, introducing a single-stream regression for benchmarks with large
average packet size. There is no single optimal buffer size for all
workloads.  For workloads with packet size <= MTU bytes, MTU + virtio-net
header-sized buffers are preferred as larger buffers reduce the TCP window
due to SKB truesize. However, single-stream workloads with large average
packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers
are used.

This commit auto-tunes the mergeable receiver buffer packet size by
choosing the packet buffer size based on an EWMA of the recent packet
sizes for the receive queue. Packet buffer sizes range from MTU_SIZE +
virtio-net header len to PAGE_SIZE. This improves throughput for
large packet workloads, as any workload with average packet size >=
PAGE_SIZE will use PAGE_SIZE buffers.

These optimizations interact positively with recent commit
ba27524103 ("virtio-net: coalesce rx frags when possible during rx"),
which coalesces adjacent RX SKB fragments in virtio_net. The coalescing
optimizations benefit buffers of any size.

Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs
between two QEMU VMs on a single physical machine. Each VM has two VCPUs
with all offloads & vhost enabled. All VMs and vhost threads run in a
single 4 CPU cgroup cpuset, using cgroups to ensure that other processes
in the system will not be scheduled on the benchmark CPUs. Trunk includes
SKB rx frag coalescing.

net-next w/ virtio_net before 2613af0ed1 (PAGE_SIZE bufs): 14642.85Gb/s
net-next (MTU-size bufs):  13170.01Gb/s
net-next + auto-tune: 14555.94Gb/s

Jason Wang also reported a throughput increase on mlx4 from 22Gb/s
using MTU-sized buffers to about 26Gb/s using auto-tuning.

Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:06 -08:00
Michael Dalton
fb51879dbc virtio-net: use per-receive queue page frag alloc for mergeable bufs
The virtio-net driver currently uses netdev_alloc_frag() for GFP_ATOMIC
mergeable rx buffer allocations. This commit migrates virtio-net to use
per-receive queue page frags for GFP_ATOMIC allocation. This change unifies
mergeable rx buffer memory allocation, which now will use skb_refill_frag()
for both atomic and GFP-WAIT buffer allocations.

To address fragmentation concerns, if after buffer allocation there
is too little space left in the page frag to allocate a subsequent
buffer, the remaining space is added to the current allocated buffer
so that the remaining space can be used to store packet data.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:06 -08:00
Michael Dalton
097b4f19e5 net: allow > 0 order atomic page alloc in skb_page_frag_refill
skb_page_frag_refill currently permits only order-0 page allocs
unless GFP_WAIT is used. Change skb_page_frag_refill to attempt
higher-order page allocations whether or not GFP_WAIT is used. If
memory cannot be allocated, the allocator will fall back to
successively smaller page allocs (down to order-0 page allocs).

This change brings skb_page_frag_refill in line with the existing
page allocation strategy employed by netdev_alloc_frag, which attempts
higher-order page allocations whether or not GFP_WAIT is set, falling
back to successively lower-order page allocations on failure. Part
of migration of virtio-net to per-receive queue page frag allocators.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 23:46:06 -08:00
Thomas Hellstrom
96b43626a5 drm/vmwgfx: Silence the device command verifier
The device and kernel module disagrees about the command length of
some commands. More pack attributes might be needed.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2014-01-17 07:52:41 +01:00
Thomas Hellstrom
f2a0dcb1aa drm/vmwgfx: Implement 64-bit Otable- and MOB binding v2
Adds the relevant commands to the device interface header and
implements 64-bit binding for 64 bit VMs.

v2: Uppercase command IDs, Correctly use also 64 bit page tables.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
2014-01-17 07:52:40 +01:00
Thomas Hellstrom
b360a3cecd drm/vmwgfx: Fix surface framebuffer check for guest-backed surfaces
With guest-backed surfaces, surface->sizes == NULL, causing a kernel oops.
Use the base_size member instead.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
2014-01-17 07:52:39 +01:00
Thomas Hellstrom
7cba9062e6 drm/vmwgfx: Update otable definitions
Update otable definitions and modify the otable setup code
accordingly.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2014-01-17 07:52:38 +01:00
Thomas Hellstrom
0fd53cfb09 drm/vmwgfx: Use the linux DMA api also for MOBs
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2014-01-17 07:52:38 +01:00
Thomas Hellstrom
4b9e45e68f drm/vmwgfx: Ditch the vmw_dummy_query_bo_prepare function
Combine it with vmw_dummy_query_bo_create, and also make sure
we use tryreserve when reserving the bo to avoid any lockdep warnings
We are sure the tryreserve will always succeed since we are
the only users at that point.
In addition, allow the vmw_bo_pin function to pin/unpin system memory.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
2014-01-17 07:52:37 +01:00
Thomas Hellstrom
173fb7d4e2 drm/vmwgfx: Persistent tracking of context bindings
Only scrub context bindings when a bound resource is destroyed, or when
the MOB backing the context is unbound.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:36 +01:00
Thomas Hellstrom
b5c3b1a6bf drm/vmwgfx: Track context bindings and scrub them upon exiting execbuf
The device is no longer capable of scrubbing context bindings of resources
that are bound when destroyed.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
2014-01-17 07:52:35 +01:00
Thomas Hellstrom
8ba07315d3 drm/vmwgfx: Block the BIND_SHADERCONSTS command
It's been deprecated.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
2014-01-17 07:52:34 +01:00
Thomas Hellstrom
311474dbdc drm/vmwgfx: Add a parameter to get max MOB memory size
Also bump minor to signal a GB-aware kernel module

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:34 +01:00
Thomas Hellstrom
1d7a5cbf8f drm/vmwgfx: Implement a buffer object synccpu ioctl.
This ioctl enables inter-process synchronization of buffer objects,
which is needed for mesa Guest-Backed objects.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
2014-01-17 07:52:33 +01:00
Zack Rusin
15c6f65623 drm/vmwgfx: Make sure that the multisampling is off
By default SVGA device creates nonmaskable multisampling surfaces, in
which case multisampleCount of 1 means: the first quality setting
of nonmaskable multisampling surface. Lets change it to make sure
that the backends know that multisampling is really off.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
2014-01-17 07:52:32 +01:00
Thomas Hellstrom
c373d4eac4 drm/vmwgfx: Extend the command verifier to handle guest-backed on / off
Make sure we disallow commands if the device doesn't support them.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:31 +01:00
Thomas Hellstrom
7086d0995c drm/vmwgfx: Fix up the vmwgfx_drv.h header for new files
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:30 +01:00
Thomas Hellstrom
d8c08b2b87 drm/vmwgfx: Enable 3D for new hardware version
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:29 +01:00
Thomas Hellstrom
74c10d1cd5 drm/vmwgfx: Add new unused (by user-space) commands to the verifier
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:29 +01:00
Thomas Hellstrom
a21aa6143f drm/vmwgfx: Validate guest-backed shader const commands
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:28 +01:00
Thomas Hellstrom
c74c162fd9 drm/vmwgfx: Add guest-backed shaders
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:27 +01:00
Thomas Hellstrom
a97e21923b drm/vmwgfx: Hook up guest-backed surfaces
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:26 +01:00
Thomas Hellstrom
58a0c5f036 drm/vmwgfx: Hook up guest-backed contexts
Contexts are managed by the kernel only, so disable access to GB
context commands from user-space

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Ruzin <zackr@vmware.com>
2014-01-17 07:52:25 +01:00
Thomas Hellstrom
f468911fee drm/vmwgfx: Detach backing store from its resources when it is evicted
When the backing store buffer is evicted, Issue a readback from the
resources and notify the resources that they are no longer bound to
a valid backing store.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:24 +01:00
Thomas Hellstrom
ddcda24e3b drm/vmwgfx: Hook up guest-backed queries
Perform a translation of legacy query commands should they occur
in the command stream.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:23 +01:00
Thomas Hellstrom
96c5f0df22 drm/vmwgfx: Add the possibility to validate a buffer as a MOB
Also do basic consistency checking.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:22 +01:00
Thomas Hellstrom
afb0e50fae drm/vmwgfx: Read bounding box memory from the appropriate register
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:22 +01:00
Thomas Hellstrom
6da768aa66 drm/vmwgfx: Hook up MOBs to TTM as a separate memory type
To bind a buffer object as a MOB, just validate it as a MOB
memory type. We are reusing the GMRID manager, although we create a new
instance of it to manage MOB ids and tomake sure we don't exceed
the maximum amount of MOB pages.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
2014-01-17 07:52:21 +01:00
Thomas Hellstrom
3530bdc35e drm/vmwgfx: Add MOB management
Implement MOB setup, binding and unbinding, but don't hook up to
TTM yet.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:19 +01:00
Thomas Hellstrom
716a2fd66d drm/vmwgfx: Adapt capability reporting to new hardware version
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>

Conflicts:
	drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c
2014-01-17 07:52:18 +01:00
Thomas Hellstrom
c1234db74d drm/vmwgfx: Update the svga register definition
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:17 +01:00
Thomas Hellstrom
bc2d6508ab drm/vmwgfx: Replace vram_size with prim_bb_mem for calculation of max resolution
In the future, Scanout buffers need not be backed by VRAM and
the two definitions will differ.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:52:16 +01:00
Thomas Hellstrom
cfe4d53eee drm/vmwgfx: Update the driver user-space interface for guest-backed objects
Not hooked up yet. This is only the definition.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>

Conflicts:
	include/uapi/drm/vmwgfx_drm.h
2014-01-17 07:47:53 +01:00
Thomas Hellstrom
d9019498dd drm/vmwgfx: Update the svga3d register header file for new device version
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
2014-01-17 07:44:24 +01:00
Thomas Hellstrom
0d00c488f3 drm/vmwgfx: Fix the driver for large dma addresses
With dma compliance / IOMMU support added to the driver in kernel 3.13,
the dma addresses can exceed 44 bits, which is what we support in
32-bit mode and with GMR1.
So in 32-bit mode and optionally in 64-bit mode, restrict the dma
addresses to 44 bits, and strip the old GMR1 code.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Cc: stable@vger.kernel.org
2014-01-17 07:44:15 +01:00
Wei Yongjun
722e47d792 net_sched: fix error return code in fw_change_attrs()
The error code was not set if change indev fail, so the error
condition wasn't reflected in the return value. Fix to return a
negative error code from this error handling case instead of 0.

Fixes: 2519a602c2 ('net_sched: optimize tcf_match_indev()')
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:12:03 -08:00
David S. Miller
8b88a11e44 Merge branch 'tipc'
Ying Xue says:

====================
tipc: align TIPC behaviours of waiting for events with other stacks

Comparing the current implementations of waiting for events in TIPC
socket layer with other stacks, TIPC's behaviour is very different
because wait_event_interruptible_timeout()/wait_event_interruptible()
are always used by TIPC to wait for events while relevant socket or
port variables are fed to them as their arguments. As socket lock has
to be released temporarily before the two routines of waiting for
events are called, their arguments associated with socket or port
structures are out of socket lock protection. This might cause
serious issues where the process of calling socket syscall such as
sendsmg(), connect(), accept(), and recvmsg(), cannot be waken up
at all even if proper event arrives or improperly be woken up
although the condition of waking up the process is not satisfied
in practice.

Therefore, aligning its behaviours with similar functions implemented
in other stacks, for instance, sk_stream_wait_connect() and
inet_csk_wait_for_connect() etc, can avoid above risks for us.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:11:22 -08:00
Ying Xue
9bbb4ecc68 tipc: standardize recvmsg routine
Standardize the behaviour of waiting for events in TIPC recvmsg()
so that all variables of socket or port structures are protected
within socket lock, allowing the process of calling recvmsg() to
be woken up at appropriate time.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:10:34 -08:00
Ying Xue
391a6dd1da tipc: standardize sendmsg routine of connected socket
Standardize the behaviour of waiting for events in TIPC send_packet()
so that all variables of socket or port structures are protected within
socket lock, allowing the process of calling sendmsg() to be woken up
at appropriate time.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:10:34 -08:00
Ying Xue
3f40504f7e tipc: standardize sendmsg routine of connectionless socket
Comparing the behaviour of how to wait for events in TIPC sendmsg()
with other stacks, the TIPC implementation might be perceived as
different, and sometimes even incorrect. For instance, sk_sleep()
and tport->congested variables associated with socket are exposed
without socket lock protection while wait_event_interruptible_timeout()
accesses them. So standardizing it with similar implementation
in other stacks can help us correct these errors which the process
of calling sendmsg() cannot be woken up event if an expected event
arrive at socket or improperly woken up although the wake condition
doesn't match.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:10:34 -08:00
Ying Xue
6398e23cdb tipc: standardize accept routine
Comparing the behaviour of how to wait for events in TIPC accept()
with other stacks, the TIPC implementation might be perceived as
different, and sometimes even incorrect. As sk_sleep() and
sk->sk_receive_queue variables associated with socket are not
protected by socket lock, the process of calling accept() may be
woken up improperly or sometimes cannot be woken up at all. After
standardizing it with inet_csk_wait_for_connect routine, we can
get benefits including: avoiding 'thundering herd' phenomenon,
adding a timeout mechanism for accept(), coping with a pending
signal, and having sk_sleep() and sk->sk_receive_queue being
always protected within socket lock scope and so on.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:10:34 -08:00
Ying Xue
78eb3a5379 tipc: standardize connect routine
Comparing the behaviour of how to wait for events in TIPC connect()
with other stacks, the TIPC implementation might be perceived as
different, and sometimes even incorrect. For instance, as both
sock->state and sk_sleep() are directly fed to
wait_event_interruptible_timeout() as its arguments, and socket lock
has to be released before we call wait_event_interruptible_timeout(),
the two variables associated with socket are exposed out of socket
lock protection, thereby probably getting stale values so that the
process of calling connect() cannot be woken up exactly even if
correct event arrives or it is woken up improperly even if the wake
condition is not satisfied in practice. Therefore, standardizing its
behaviour with sk_stream_wait_connect routine can avoid these risks.

Additionally the implementation of connect routine is simplified as a
whole, allowing it to return correct values in all different cases.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16 19:10:34 -08:00