Commit graph

576,624 commits

Author SHA1 Message Date
Daniel Lezcano
351bb99b71 clocksource/drivers/vt8500: Remove unneeded header
Remove the <asm/time.h> header inclusion which is pointless.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:40 +01:00
Daniel Lezcano
adce4bc831 clocksource/drivers/tegra2: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Due to the non portable code for the delay timer, this option is only
available for the ARM architecture.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:39 +01:00
Daniel Lezcano
f0c5afb787 clocksource/drivers/sun5i: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

The driver depends on the common clock framework, thus the dependency added
on COMMON_CLK.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:37 +01:00
Daniel Lezcano
b4fcd48b88 clocksource/drivers/sun4i: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:35 +01:00
Arnd Bergmann
2b749cb3a5 ARM: realview: remove private barrier implementation
The realview barrier implementation tries to avoid calling outer_sync in order
to not lock up as a result of a bug in the l220 cache controller.

This gets in the way of the multiplatform support, but we can still remove
it if we make sure that the outer_sync function never gets called, by replacing
the function pointer with NULL, right after initialization.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[Fixed up header inclusions]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-15 09:41:34 +01:00
Daniel Lezcano
5b097f6ba5 clocksource/drivers/dw_apb: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:34 +01:00
Arnd Bergmann
38541bf485 ARM: no longer force unbuffered DMA for realview
Commit 42c4dafe80 ("ARM: 6202/1: Do not ARM_DMA_MEM_BUFFERABLE
on RealView boards with L210/L220") changed the generic setting for
ARM_DMA_MEM_BUFFERABLE to be disabled on any Realview kernel that includes
support for any of the ARM11 variations. Doing this was required to
allow doing DMA without a lockup in the l2x0 cache controller on the
Realview platform.

Unfortunately, in a kernel that also contains support for any ARMv7
based machine, the same change makes it impossible to do DMA on ARMv7,
which gets in the way of enabling multiplatform support on Realview.

As confirmed by Catalin Marinas and Linus Walleij, the current
code for Realview that we have in the kernel does not actually
perform any DMA, and this is unlikely to change in the future.
Therefore we can revert 42c4dafe80 without introducing regressions,
but we must never start using DMA on this platform in the future.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-15 09:41:33 +01:00
Arnd Bergmann
3c30a4a357 clk/realview: stop using machine headers
In order to move realview into multiplatform, we have to prevent device
drivers from accessing the machine header files.

In case of the clk driver, this is very simple, we just copy the
small set of register definitions into the driver that needs them.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-15 09:41:33 +01:00
Daniel Lezcano
e6c1db13f9 clocksource/drivers/digicolor: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:32 +01:00
Arnd Bergmann
930748a033 ARM: realview: don't map undefined PCI registers
PCI support for realview was never merged, and trying to build realview with
CONFIG_PCI enabled fails because the constants for the mapping windows are
not defined anywhere.

This removes them from the static I/O window mapping table as a preparation
for multiplatform support.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-15 09:41:32 +01:00
Arnd Bergmann
fd0053c9eb ARM: realview: remove sparsemem hack
The realview-pbx platform has an elaborate way of avoiding the use of highmem
by redefining its phys_to_virt function. In practice this doesn't help all
that much, and it gets in the way of doing multiplatform builds for
realview.

This removes the feature and kills off the mach/memory.h file for realview.
We also lose the ability to do sparsemem with this patch, but that should
be put back into place for generic multiplatform configurations, to save
a little memory on PBX.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-15 09:41:31 +01:00
Daniel Lezcano
c916554971 clocksource/drivers/orion: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

The driver is using the atomic_io API which is not portable, so the
compilation is restricted to ARM only.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:30 +01:00
Daniel Lezcano
0b7a7bb705 clocksource/drivers/meson6: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:29 +01:00
Daniel Lezcano
9519e80c75 clocksource/drivers/armada-370-xp: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Due to the non portable 'delay' code, the compilation is restricted to the
ARM architecture only.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:27 +01:00
Daniel Lezcano
40ada2aac5 clocksource/drivers/rockchip: Add COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Due to the dsb() usage in the driver, this driver is only compilable on
ARM and ARM64.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:25 +01:00
Daniel Lezcano
fbca9eabe9 clocksource/drivers/mediatek: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:24 +01:00
Daniel Lezcano
dfdb16525b clocksource/drivers/pistachio: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:22 +01:00
Daniel Lezcano
5a7351f0e1 clocksource/drivers/tango: Add COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:20 +01:00
Daniel Lezcano
5ae996cbee clocksource/drivers/pxa_timer: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:19 +01:00
Daniel Lezcano
389d9b5841 clocksource/drivers/pxa_timer: Move the Kconfig rule
Instead of having the clocksource's Kconfig depending on the arch, let the
arch to select the timer it needs.

The CLKSRC_OF dependency is removed because already selected by the
ARCH_PXA, and it is added for SA1100.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:17 +01:00
Daniel Lezcano
baacaf8338 clocksource/drivers/st_lpc: Add the COMPILE_TEST option
Increase the compilation test coverage by adding the COMPILE_TEST option.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:15 +01:00
Daniel Lezcano
2ffdf71b83 clocksource/drivers/st_lpc: Fix Kconfig dependency
Change the Kconfig selection rule by letting the STI arch to select
the timer.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
2015-12-15 09:41:14 +01:00
Daniel Lezcano
3dc0e9f6fd clocksource/drivers/qcom: Make COMPILE_TEST enabled for ARM architecture
In order to be consistent with the rest of the drivers compilation, let's
introduce the COMPILE_TEST option. Unfortunately, the delay.h code is not
portable, so the compilation test coverage will be restricted to the ARM
architecture.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:12 +01:00
Caesar Wang
23b8f81f38 clocksource/drivers/rockchip: Remove dsb() usage
The dsb() instruction is pointless in this code.

Remove it.

That also fixes the ARM64 compilation issue.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
2015-12-15 09:41:11 +01:00
Daniel Lezcano
364eba4b3a time: Define dummy functions for the generic sched clock
When we try to compile a clocksource driver with the COMPILE_TEST option,
we can't select the GENERIC_SCHED_CLOCK because the sched_clock() symbol
will be duplicated with the one defined for the x86.

In order to fix that, we don't select the GENERIC_SCHED_CLOCK in the
driver Kconfig's file but we define some empty functions for the different
symbols in order to prevent the unresolved ones.

This patch fixes the COMPILE_TEST option for the compile test coverage for
the clocksource drivers. Without this patch, we can't add the COMPILE_TEST
option for the clocksource drivers using the GENERIC_SCHED_CLOCK.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:09 +01:00
Caesar Wang
a0d2216ec0 clocksource/drivers/rockchip: Make the driver more readable
Let's checkstyle to clean up the macros with such trivial details.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:07 +01:00
Lucas Stach
a3a8908fb0 clocksource/drivers/tegra: Allow timer irq affinity change
Allow the timer core to change the smp affinity of the broadcast timer
irq by setting CLOCK_EVT_FEAT_DYNIRQ flag.

This reduces interrupt pressure and wakeups on CPU0 as well as vastly
reducing the number of timer broadcast IPIs.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:06 +01:00
Alexey Klimov
11faa20eb4 clocksource/drivers/mtk_timer: Fix memleak in mtk_timer_init()
Add error path to clear evt struct allocated by kzalloc() in the beginning of
function mtk_timer_init().

Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:04 +01:00
Alexey Klimov
6cd7ccaaa8 clocksource/drivers/mtk_timer: Fix pr_warn() messages in mtk_timer_init
1) Change pr_warn()s to pr_err()s. These messages are actually errors and not
   warnings.
2) Add missing \n.
3) Error message for kzalloc() failure is removed per suggestion by Joe Perches.
   There is generic stack_dump() for allocation issues.

Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:02 +01:00
Alexey Klimov
9a78ec45bd clocksource/drivers/mtk_timer: Add pr_fmt define
It's a bit unclear what subsystem/driver emits some messages to dmesg in
the function mtk_init_timer(). Use pr_fmt to auto-prefix the messages
appropriately.

Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-15 09:41:00 +01:00
Dan Williams
979fccfb73 libnvdimm, pfn: enable pfn sysfs interface unit testing
The unit test infrastructure uses CMA and real memory to emulate nvdimm
resources.  The call to devm_memremap_pages() can simply be mocked in
the same manner as memremap and we mock phys_to_pfn_t() to clear PFN_MAP
since these resources are not registered with in the pgmap_radix.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-12-15 00:34:21 -08:00
Andy Gross
1f0947fe3a soc: qcom: smd-rpm: Add existing platform support
This patch adds support for all current Qualcomm platforms which utilize
RPM over SMD.  This includes both MSM8916 and APQ8084.

Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Andy Gross <agross@codeaurora.org>
2015-12-14 23:58:32 -06:00
Vlad Yasevich
f654861569 skbuff: Fix offset error in skb_reorder_vlan_header
skb_reorder_vlan_header is called after the vlan header has
been pulled.  As a result the offset of the begining of
the mac header has been incrased by 4 bytes (VLAN_HLEN).
When moving the mac addresses, include this incrase in
the offset calcualation so that the mac addresses are
copied correctly.

Fixes: a6e18ff111 (vlan: Fix untag operations of stacked vlans with REORDER_HEADER off)
CC: Nicolas Dichtel <nicolas.dichtel@6wind.com>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: Vladislav Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 00:30:41 -05:00
WANG Cong
09ccfd238e pptp: verify sockaddr_len in pptp_bind() and pptp_connect()
Reported-by: Dmitry Vyukov <dvyukov@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 00:29:34 -05:00
Kazuya Mizuguchi
54499969c9 ravb: Add disable 10base
Ethernet AVB does not support 10 Mbps transfer speed.

Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 00:26:31 -05:00
Sergei Shtylyov
1299653aff sh_eth: fix descriptor access endianness
The driver never  calls cpu_to_edmac() when writing the descriptor address
and edmac_to_cpu() when reading it, although it should -- fix this.

Note that the frame/buffer length descriptor field accesses also need fixing
but since they are both 16-bit we can't  use {cpu|edmac}_to_{edmac|cpu}()...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 00:25:00 -05:00
Sergei Shtylyov
3e2309937f sh_eth: fix TX buffer byte-swapping
For the little-endian SH771x kernels the driver has to byte-swap the RX/TX
buffers,  however yet unset physcial address from the TX descriptor is used
to call sh_eth_soft_swap(). Use 'skb->data' instead...

Fixes: 31fcb99d99 ("net: sh_eth: remove __flush_purge_region")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 00:25:00 -05:00
Eric Dumazet
5037e9ef94 net: fix IP early demux races
David Wilder reported crashes caused by dst reuse.

<quote David>
  I am seeing a crash on a distro V4.2.3 kernel caused by a double
  release of a dst_entry.  In ipv4_dst_destroy() the call to
  list_empty() finds a poisoned next pointer, indicating the dst_entry
  has already been removed from the list and freed. The crash occurs
  18 to 24 hours into a run of a network stress exerciser.
</quote>

Thanks to his detailed report and analysis, we were able to understand
the core issue.

IP early demux can associate a dst to skb, after a lookup in TCP/UDP
sockets.

When socket cache is not properly set, we want to store into
sk->sk_dst_cache the dst for future IP early demux lookups,
by acquiring a stable refcount on the dst.

Problem is this acquisition is simply using an atomic_inc(),
which works well, unless the dst was queued for destruction from
dst_release() noticing dst refcount went to zero, if DST_NOCACHE
was set on dst.

We need to make sure current refcount is not zero before incrementing
it, or risk double free as David reported.

This patch, being a stable candidate, adds two new helpers, and use
them only from IP early demux problematic paths.

It might be possible to merge in net-next skb_dst_force() and
skb_dst_force_safe(), but I prefer having the smallest patch for stable
kernels : Maybe some skb_dst_force() callers do not expect skb->dst
can suddenly be cleared.

Can probably be backported back to linux-3.6 kernels

Reported-by: David J. Wilder <dwilder@us.ibm.com>
Tested-by: David J. Wilder <dwilder@us.ibm.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-14 23:52:00 -05:00
Kouei Abe
1fd6b873c2 arm64: defconfig: Add Renesas R-Car SATA driver for R-Car Gen3 SoCs
This adds Renesas sata_rcar driver to defconfig.

Signed-off-by: Kouei Abe <kouei.abe.cp@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2015-12-15 13:21:23 +09:00
Benjamin Poirier
0a8047ac68 e1000e: Fix msi-x interrupt automask
Since the introduction of 82574 support in e1000e, the driver has worked
on the assumption that msi-x interrupt generation is automatically
disabled after each irq. As it turns out, this is not the case.
Currently, rx interrupts can fire multiple times before and during napi
processing. This can be a problem for users because frames that arrive
in a certain window (after adapter->clean_rx() but before
napi_complete_done() has cleared NAPI_STATE_SCHED) generate an interrupt
which does not lead to napi_schedule(). These frames sit in the rx queue
until another frame arrives (a tcp retransmit for example).

While the EIAC and CTRL_EXT registers are properly configured for irq
automask, the modification of IAM in e1000_configure_msix() is what
prevents automask from working as intended.

This patch removes that erroneous write and fixes interrupt rearming for
tx interrupts. It also clears IAME from CTRL_EXT. This is not strictly
necessary for operation of the driver but it is to avoid disruption from
potential programs that access the registers directly, like `ethregs -c`.

Reported-by: Frank Steiner <steiner-reg@bio.ifi.lmu.de>
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-12-14 20:19:47 -08:00
Wolfram Sang
691cd0a64d ARM: shmobile: r8a7794: dtsi: add internal delay for i2c IPs
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2015-12-15 13:14:08 +09:00
Wolfram Sang
49160dc19f ARM: shmobile: r8a7791: dtsi: add internal delay for i2c IPs
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2015-12-15 13:13:58 +09:00
Wolfram Sang
ac8e7f31c7 ARM: shmobile: r8a7790: dtsi: add internal delay for i2c IPs
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2015-12-15 13:13:40 +09:00
Benjamin Poirier
a61cfe4ffa e1000e: Do not write lsc to ics in msi-x mode
In msi-x mode, there is no handler for the lsc interrupt so there is no
point in writing that to ics now that we always assume Other interrupts
are caused by lsc.

Reviewed-by: Jasna Hodzic <jhodzic@ucdavis.edu>
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-12-14 20:09:18 -08:00
Benjamin Poirier
16ecba59bc e1000e: Do not read ICR in Other interrupt
Removes the ICR read in the other interrupt handler, uses EIAC to
autoclear the Other bit from ICR and IMS. This allows us to avoid
interference with Rx and Tx interrupts in the Other interrupt handler.

The information read from ICR is not needed. IMS is configured such that
the only interrupt cause that can trigger the Other interrupt is Link
Status Change.

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-12-14 19:36:13 -08:00
Benjamin Poirier
4d432f67ff e1000e: Remove unreachable code
msi-x interrupts are not shared so there's no need to check if the
interrupt was really from this adapter.

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-12-14 19:30:21 -08:00
Vitaly Kuznetsov
940b68e2c3 Drivers: hv: ring_buffer: eliminate hv_ringbuffer_peek()
Currently, there is only one user for hv_ringbuffer_read()/
hv_ringbuffer_peak() functions and the usage of these functions is:
- insecure as we drop ring_lock between them, someone else (in theory
  only) can acquire it in between;
- non-optimal as we do a number of things (acquire/release the above
  mentioned lock, calculate available space on the ring, ...) twice and
  this path is performance-critical.

Remove hv_ringbuffer_peek() moving the logic from __vmbus_recvpacket() to
hv_ringbuffer_read().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 19:27:30 -08:00
Vitaly Kuznetsov
667d374064 Drivers: hv: remove code duplication between vmbus_recvpacket()/vmbus_recvpacket_raw()
vmbus_recvpacket() and vmbus_recvpacket_raw() are almost identical but
there are two discrepancies:
1) vmbus_recvpacket() doesn't propagate errors from hv_ringbuffer_read()
   which looks like it is not desired.
2) There is an error message printed in packetlen > bufferlen case in
   vmbus_recvpacket(). I'm removing it as it is usless for users to see
   such messages and /vmbus_recvpacket_raw() doesn't have it.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 19:27:30 -08:00
Vitaly Kuznetsov
b5f53dde8d Drivers: hv: ring_buffer: remove code duplication from hv_ringbuffer_peek/read()
hv_ringbuffer_peek() does the same as hv_ringbuffer_read() without
advancing the read index. The only functional change this patch brings
is moving hv_need_to_signal_on_read() call under the ring_lock but this
function is just a couple of comparisons.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 19:27:30 -08:00
Vitaly Kuznetsov
45870a4413 Drivers: hv: ring_buffer: remove stray smp_read_barrier_depends()
smp_read_barrier_depends() does nothing on almost all arcitectures
including x86 and having it in the beginning of
hv_get_ringbuffer_availbytes() does not provide any guarantees anyway.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 19:27:30 -08:00