- Set correct AHB clock for i.MX8MN SDMA1 device to fix a "Timeout
waiting for CH0" error.
- Fix a linker error for i.MX6 configurations that have ARM_CPU_SUSPEND=n,
which can happen if neither CONFIG_PM, CONFIG_CPU_IDLE, nor ARM_PSCI_FW
are selected.
- Fix I2C1 pinctrl configuration for i.MX27 phytec-phycard board.
- Fix i.MX8M AIPS 'reg' properties to remove DTC simple_bus_reg
warnings.
- Add missing compatible "fsl,vf610-edma" for LS1028A EDMA device, so
that bootloader can fix up the IOMMU entries there. Otherwise, EDMA
just doesn't work on LS1028A with shipped bootloader.
- Fix imx6dl-yapp4-ursa board Ethernet connection.
- Fix input_val for AUDIOMIX_BIT_STREAM pinctrl defines on i.MX8MP
according to Reference Manual.
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Merge tag 'imx-fixes-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into arm/fixes
i.MX fixes for 5.7:
- Set correct AHB clock for i.MX8MN SDMA1 device to fix a "Timeout
waiting for CH0" error.
- Fix a linker error for i.MX6 configurations that have ARM_CPU_SUSPEND=n,
which can happen if neither CONFIG_PM, CONFIG_CPU_IDLE, nor ARM_PSCI_FW
are selected.
- Fix I2C1 pinctrl configuration for i.MX27 phytec-phycard board.
- Fix i.MX8M AIPS 'reg' properties to remove DTC simple_bus_reg
warnings.
- Add missing compatible "fsl,vf610-edma" for LS1028A EDMA device, so
that bootloader can fix up the IOMMU entries there. Otherwise, EDMA
just doesn't work on LS1028A with shipped bootloader.
- Fix imx6dl-yapp4-ursa board Ethernet connection.
- Fix input_val for AUDIOMIX_BIT_STREAM pinctrl defines on i.MX8MP
according to Reference Manual.
* tag 'imx-fixes-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
arm64: dts: freescale: imx8mp: update input_val for AUDIOMIX_BIT_STREAM
arm64: dts: imx8m: Fix AIPS reg properties
arm64: dts: imx8mn: Change SDMA1 ahb clock for imx8mn
ARM: dts: imx27-phytec-phycard-s-rdk: Fix the I2C1 pinctrl entries
ARM: imx: provide v7_cpu_resume() only on ARM_CPU_SUSPEND=y
ARM: dts: imx6dl-yapp4: Fix Ursa board Ethernet connection
arm64: dts: ls1028a: add "fsl,vf610-edma" compatible
dt-bindings: dma: fsl-edma: fix ls1028a-edma compatible
Link: https://lore.kernel.org/r/20200429063226.GT32592@dragon
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This reduces the (hard coded) CPU voltage to a safe level on MSM8996 and
updates the audio nodes on db820c, db845c and c630 to reflect audio
changes that landed late in the cycle.
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Merge tag 'qcom-arm64-fixes-for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux into arm/fixes
Qualcomm ARM64 DT fixes for v5.7
This reduces the (hard coded) CPU voltage to a safe level on MSM8996 and
updates the audio nodes on db820c, db845c and c630 to reflect audio
changes that landed late in the cycle.
* tag 'qcom-arm64-fixes-for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux:
arm64: dts: qcom: db820c: fix audio configuration
arm64: dts: qcom: db845c: fix asm dai setup
arm64: qcom: c630: fix asm dai setup
arm64: dts: qcom: msm8996: Reduce vdd_apc voltage
Link: https://lore.kernel.org/r/20200429052932.GA2627045@builder.lan
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
i915_gem_evict_something() is charged with finding a slot within the GTT
that we may reuse. Since our goal is not to stall, we first look for a
slot that only overlaps idle vma. To this end, on the first pass we move
any active vma to the end of the search list. However, we only stopped
moving active vma after we see the first active vma twice. If during the
search, that first active vma completed, we would not notice and keep on
extending the search list.
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1746
Fixes: 2850748ef8 ("drm/i915: Pull i915_vma_pin under the vm->mutex")
Fixes: b1e3177bd1 ("drm/i915: Coordinate i915_active with its own mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200509115217.26853-1-chris@chris-wilson.co.uk
(cherry picked from commit 73e28cc40b)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
On some msm8916 devices, attempts at initializing coresight cause the boot to
fail. This was fixed by disabling the coresight-related nodes in the board dts
files. However, a cleaner approach was chosen for fixing the same issue on
msm8998: disabling coresight by default, and enabling it in board dts files
where desired.
This patch implements the same solution for msm8916, removes now redundant
overwrites in board specific dts files and and enables coresight in db410c's
board dts in order to keep the current behavior.
Fixes: b1fcc5702a ("arm64: dts: qcom: msm8916: Add CTI options")
Signed-off-by: Michael Srba <michael.srba@seznam.cz>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Link: https://lore.kernel.org/r/20200513184735.30104-1-michael.srba@seznam.cz
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Pull MD changes from Song.
* 'md-next' of git://git.kernel.org/pub/scm/linux/kernel/git/song/md:
md/raid1: Replace zero-length array with flexible-array
md: add a newline when printing parameter 'start_ro' by sysfs
md: stop using ->queuedata
md/raid1: release pending accounting for an I/O only after write-behind is also finished
md: remove redundant memalloc scope API usage
raid5: update code comment of scribble_alloc()
raid5: remove gfp flags from scribble_alloc()
md: use memalloc scope APIs in mddev_suspend()/mddev_resume()
md: remove the extra line for ->hot_add_disk
md: flush md_rdev_misc_wq for HOT_ADD_DISK case
md: don't flush workqueue unconditionally in md_open
md: add new workqueue for delete rdev
md: add checkings before flush md_misc_wq
The AR8031/AR8033 and the AR8035 support cable diagnostics. Adding
driver support is straightforward, so lets add it.
The PHY just do one pair at a time, so we have to start the test four
times. The cable_test_get_status() can block and therefore we can just
busy poll the test completion and continue with the next pair until we
are done.
The time delta counter seems to run at 125MHz which just gives us a
resolution of about 82.4cm per tick.
100m cable, A/B/C/D open:
Cable test started for device eth0.
Cable test completed for device eth0.
Pair: Pair A, result: Open Circuit
Pair: Pair A, fault length: 107.94m
Pair: Pair B, result: Open Circuit
Pair: Pair B, fault length: 104.64m
Pair: Pair C, result: Open Circuit
Pair: Pair C, fault length: 105.47m
Pair: Pair D, result: Open Circuit
Pair: Pair D, fault length: 107.94m
1m cable, A/B connected, C shorted, D open:
Cable test started for device eth0.
Cable test completed for device eth0.
Pair: Pair A, result: OK
Pair: Pair B, result: OK
Pair: Pair C, result: Short within Pair
Pair: Pair C, fault length: 0.82m
Pair: Pair D, result: Open Circuit
Pair: Pair D, fault length: 0.82m
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These were used to set various timeouts for the reset procedure
(deciding when the engine was dead, and even if the reset itself was not
making forward progress). No longer used.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513074809.18194-14-chris@chris-wilson.co.uk
While do_ipv6_getsockopt does not call the high-level recvmsg helper,
the msghdr eventually ends up being passed to put_cmsg anyway, and thus
needs msg_control_is_user set to the proper value.
Fixes: 1f466e1f15 ("net: cleanly handle kernel vs user buffers for ->msg_control")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The initial-breadcrumb is used to mark the end of the awaiting and the
beginning of the user payload. We verify that we do not start the user
payload before all signaler are completed, checking our semaphore setup
by looking for the initial breadcrumb being written too early. We also
want to ensure that we do not add semaphore waits after we have already
closed the semaphore section, an issue for later deferred waits.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513165937.9508-2-chris@chris-wilson.co.uk
Michael Walle says:
====================
net: phy: broadcom: cable tester support
Add cable tester support for the Broadcom PHYs. Support for it was
developed on a BCM54140 Quad PHY which RDB register access.
If there is a link partner the results are not as good as with an open
cable. I guess we could retry if the measurement until all pairs had at
least one valid result.
changes since v1:
- added Reviewed-by: tags
- removed "div by 2" for cross shorts, just mention it in the commit
message. The results are inconclusive if the tests are repeated. So
just report the length as is for now.
- fixed typo in commit message
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the generic cable tester functions from bcm-phy-lib to add cable
tester support.
100m cable, A/B/C/D open:
Cable test started for device eth0.
Cable test completed for device eth0.
Pair: Pair A, result: Open Circuit
Pair: Pair B, result: Open Circuit
Pair: Pair C, result: Open Circuit
Pair: Pair D, result: Open Circuit
Pair: Pair A, fault length: 106.60m
Pair: Pair B, fault length: 103.32m
Pair: Pair C, fault length: 104.96m
Pair: Pair D, fault length: 106.60m
1m cable, A/B connected, pair C shorted, D open:
Cable test started for device eth0.
Cable test completed for device eth0.
Pair: Pair A, result: OK
Pair: Pair B, result: OK
Pair: Pair C, result: Short within Pair
Pair: Pair D, result: Open Circuit
Pair: Pair C, fault length: 0.82m
Pair: Pair D, fault length: 1.64m
1m cable, A/B connected, pair C shorted with D:
Cable test started for device eth0.
Cable test completed for device eth0.
Pair: Pair A, result: OK
Pair: Pair B, result: OK
Pair: Pair C, result: Short to another pair
Pair: Pair D, result: Short to another pair
Pair: Pair C, fault length: 1.64m
Pair: Pair D, fault length: 1.64m
The granularity of the length measurement seems to be 82cm.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most modern broadcom PHYs support ECD (enhanced cable diagnostics). Add
support for it in the bcm-phy-lib so they can easily be used in the PHY
driver.
There are two access methods for ECD: legacy by expansion registers and
via the new RDB registers which are exclusive. Provide functions in two
variants where the PHY driver can choose from. To keep things simple for
now, we just switch the register access to expansion registers in the
RDB variant for now. On the flipside, we have to keep a bus lock to
prevent any other non-legacy access on the PHY.
The results of the intra-pair tests are inconclusive (at least for the
BCM54140). Most of the times half the length is reported but sometimes
the length is correct.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the convenience function to do a read-modify-write. This has the
additional benefit of saving one write to the selection register.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add helper to read and write expansion registers without taking the mdio
lock.
Please note, that this changes the semantics of the read and write.
Before there was no lock between selecting the expansion register and
the actual read/write. This may lead to access failures if there are
parallel accesses. Instead take the bus lock during the whole access
cycle.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The GENET controller on the Raspberry Pi 4 (2711) is typically
interfaced with an external Broadcom PHY via a RGMII electrical
interface. To make sure that delays are properly configured at the PHY
side, ensure that we the dedicated Broadcom PHY driver
(CONFIG_BROADCOM_PHY) is enabled for this to happen.
Fixes: 402482a6a7 ("net: bcmgenet: Clear ID_MODE_DIS in EXT_RGMII_OOB_CTRL when not needed")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add initial cable testing support.
This PHY needs only 100usec for this test and it is recommended to run it
before the link is up. For now, provide at least ethtool support, so it
can be tested by more developers.
This patch was tested with TJA1102 PHY with following results:
- No cable, is detected as open
- 1m cable, with no connected other end and detected as open
- a 40m cable (out of spec, max lenght should be 15m) is detected as OK.
Current patch do not provide polarity test support. This test would
indicate not proper wire connection, where "+" wire of main phy is
connected to the "-" wire of the link partner.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tuong Lien says:
====================
tipc: add some patches
This series adds patches to fix some issues in TIPC streaming & service
subscription.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When a service subscription is expired or canceled by user, it needs to
be deleted from the subscription list, so that new subscriptions can be
registered (max = 65535 per net). However, there are two issues in code
that can cause such an unused subscription to persist:
1) The 'tipc_conn_delete_sub()' has a loop on the subscription list but
it makes a break shortly when the 1st subscription differs from the one
specified, so the subscription will not be deleted.
2) In case a subscription is canceled, the code to remove the
'TIPC_SUB_CANCEL' flag from the subscription filter does not work if it
is a local subscription (i.e. the little endian isn't involved). So, it
will be no matches when looking for the subscription to delete later.
The subscription(s) will be removed eventually when the user terminates
its topology connection but that could be a long time later. Meanwhile,
the number of available subscriptions may be exhausted.
This commit fixes the two issues above, so as needed a subscription can
be deleted correctly.
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Upon receipt of a service subscription request from user via a topology
connection, one 'sub' object will be allocated in kernel, so it will be
able to send an event of the service if any to the user correspondingly
then. Also, in case of any failure, the connection will be shutdown and
all the pertaining 'sub' objects will be freed.
However, there is a race condition as follows resulting in memory leak:
receive-work connection send-work
| | |
sub-1 |<------//-------| |
sub-2 |<------//-------| |
| |<---------------| evt for sub-x
sub-3 |<------//-------| |
: : :
: : :
| /--------| |
| | * peer closed |
| | | |
| | |<-------X-------| evt for sub-y
| | |<===============|
sub-n |<------/ X shutdown |
-> orphan | |
That is, the 'receive-work' may get the last subscription request while
the 'send-work' is shutting down the connection due to peer close.
We had a 'lock' on the connection, so the two actions cannot be carried
out simultaneously. If the last subscription is allocated e.g. 'sub-n',
before the 'send-work' closes the connection, there will be no issue at
all, the 'sub' objects will be freed. In contrast the last subscription
will become orphan since the connection was closed, and we released all
references.
This commit fixes the issue by simply adding one test if the connection
remains in 'connected' state right after we obtain the connection lock,
then a subscription object can be created as usual, otherwise we ignore
it.
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Reported-by: Thang Ngo <thang.h.ngo@dektech.com.au>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently when a connection is in Nagle mode, we set the 'ack_required'
bit in the last sending buffer and wait for the corresponding ACK prior
to pushing more data. However, on the receiving side, the ACK is issued
only when application really reads the whole data. Even if part of the
last buffer is received, we will not do the ACK as required. This might
cause an unnecessary delay since the receiver does not always fetch the
message as fast as the sender, resulting in a large latency in the user
message sending, which is: [one RTT + the receiver processing time].
The commit makes Nagle ACK as soon as possible i.e. when a message with
the 'ack_required' arrives in the receiving side's stack even before it
is processed or put in the socket receive queue...
This way, we can limit the streaming latency to one RTT as committed in
Nagle mode.
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Yonghong Song says:
====================
Commit ae24345da5 ("bpf: Implement an interface to register
bpf_iter targets") and its subsequent commits in the same patch set
introduced bpf iterator, a way to run bpf program when iterating
kernel data structures.
This patch set addressed some followup issues. One big change
is to allow target to pass ctx arg register types to verifier
for verification purpose. Please see individual patch for details.
Changelogs:
v1 -> v2:
. add "const" qualifier to struct bpf_iter_reg for
bpf_iter_[un]reg_target, and this results in
additional "const" qualifiers in some other places
. drop the patch which will issue WARN_ONCE if
seq_ops->show() returns a positive value.
If this does happen, code review should spot
this or author does know what he is doing.
In the future, we do want to implement a
mechanism to find out all registered targets
so we will be aware of new additions.
====================
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The code had historically been ignoring these errors, and my recent
refactoring changed that, which broke ssh in some setups.
Fixes: 2618d530dd ("net/scm: cleanup scm_detach_fds")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 5fbc220862 ("tools/libpf: Add offsetof/container_of macro
in bpf_helpers.h") added macros offsetof/container_of to
bpf_helpers.h. Unfortunately, it caused compilation warnings
below for a few samples/bpf programs:
In file included from /data/users/yhs/work/net-next/samples/bpf/sockex2_kern.c:4:
In file included from /data/users/yhs/work/net-next/include/uapi/linux/in.h:24:
In file included from /data/users/yhs/work/net-next/include/linux/socket.h:8:
In file included from /data/users/yhs/work/net-next/include/linux/uio.h:8:
/data/users/yhs/work/net-next/include/linux/kernel.h:992:9: warning: 'container_of' macro redefined [-Wmacro-redefined]
^
/data/users/yhs/work/net-next/tools/lib/bpf/bpf_helpers.h:46:9: note: previous definition is here
^
1 warning generated.
CLANG-bpf samples/bpf/sockex3_kern.o
In all these cases, bpf_helpers.h is included first, followed by other
standard headers. The macro container_of is defined unconditionally
in kernel.h, causing the compiler warning.
The fix is to move bpf_helpers.h after standard headers.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180223.2949987-1-yhs@fb.com
Commit b121b341e5 ("bpf: Add PTR_TO_BTF_ID_OR_NULL
support") adds a field btf_id_or_null_non0_off to
bpf_prog->aux structure to indicate that the
first ctx argument is PTR_TO_BTF_ID reg_type and
all others are PTR_TO_BTF_ID_OR_NULL.
This approach does not really scale if we have
other different reg types in the future, e.g.,
a pointer to a buffer.
This patch enables bpf_iter targets registering ctx argument
reg types which may be different from the default one.
For example, for pointers to structures, the default reg_type
is PTR_TO_BTF_ID for tracing program. The target can register
a particular pointer type as PTR_TO_BTF_ID_OR_NULL which can
be used by the verifier to enforce accesses.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180221.2949882-1-yhs@fb.com
Change func bpf_iter_unreg_target() parameter from target
name to target reg_info, similar to bpf_iter_reg_target().
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180220.2949737-1-yhs@fb.com
Currently bpf_iter_reg_target takes parameters from target
and allocates memory to save them. This is really not
necessary, esp. in the future we may grow information
passed from targets to bpf_iter manager.
The patch refactors the code so target reg_info
becomes static and bpf_iter manager can just take
a reference to it.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200513180219.2949605-1-yhs@fb.com
Add a short comment in bpf_iter_run_prog() function to
explain how bpf_prog return value is converted to
seq_ops->show() return value:
bpf_prog return seq_ops()->show() return
0 0
1 -EAGAIN
When show() return value is -EAGAIN, the current
bpf_seq_read() will end. If the current seq_file buffer
is empty, -EAGAIN will return to user space. Otherwise,
the buffer will be copied to user space.
In both cases, the next bpf_seq_read() call will
try to show the same object which returned -EAGAIN
previously.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180218.2949517-1-yhs@fb.com
This is to be consistent with tracing and lsm programs
which have prefix "bpf_trace_" and "bpf_lsm_" respectively.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180216.2949387-1-yhs@fb.com
Commit 6879c042e1 ("tools/bpf: selftests: Add bpf_iter selftests")
added self tests for bpf_iter feature. But two subtests
ipv6_route and netlink needs llvm latest 10.x release branch
or trunk due to a bug in llvm BPF backend. This patch added
the file README.rst to document these two failures
so people using llvm 10.0.0 can be aware of them.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200513180215.2949237-1-yhs@fb.com
Martin Blumenstingl says:
====================
dwmac-meson8b Ethernet RX delay configuration
The Ethernet TX performance has been historically bad on Meson8b and
Meson8m2 SoCs because high packet loss was seen. I found out that this
was related (yet again) to the RGMII TX delay configuration.
In the process of discussing the big picture (and not just a single
patch) [0] with Andrew I discovered that the IP block behind the
dwmac-meson8b driver actually seems to support the configuration of the
RGMII RX delay (at least on the Meson8b SoC generation).
Since I sent the first RFC I got additional documentation from Jianxin
(many thanks!). Also I have discovered some more interesting details:
- Meson8b Odroid-C1 requires an RX delay (by either the PHY or the MAC)
Based on the vendor u-boot code (not upstream) I assume that it will
be the same for all Meson8b and Meson8m2 boards
- Khadas VIM2 seems to have the RX delay built into the PCB trace
length. When I enable the RX delay on the PHY or MAC I can't get any
data through. I expect that we will have the same situation on all
GXBB, GXM, AXG, G12A, G12B and SM1 boards. Further clarification is
needed here though (since I can't visually see these lengthened
traces on the PCB). This will be done before sending patches for
these boards.
Dependencies for this series:
There is a soft dependency for patch #2 on commit f22531438f
"dt-bindings: net: dwmac: increase 'maxItems' for 'clocks',
'clock-names' properties" which is currently in Rob's -next tree.
That commit is needed to make the dt-bindings schema validation
pass for patch #2. That patch has been for ~4 weeks in Robs tree,
so I assume that is not going to be dropped.
Changes since RFC v2 at [2]:
- dropped $ref: /schemas/types.yaml#definitions/uint32 from the
"amlogic,rx-delay-ns" in patch #1 ("Don't need to define the
type when in standard units." says Rob - thanks, I learned
something new). Also use "default: 0" for for this property
instead of explaining it in the description text.
- added a note to the cover-letter about a hidden dependency for
dt-binding schema validation in patch #2
- Added Andrew's Reviewed-by to patches 1-7. Thank you again for
the quick and detailed reviews, I appreciate this!
- error out if the (optional) timing-adjustment clock is missing
but we're asked to enable the RGMII RX delay. The MAC won't
work in this specific case and either the RX delay has to be
provided by the PHY or the timing-adjustment clock has to be
added.
- dropped the dts patches (#9-11) which were only added to give
an overview how this is going to be used. those will be sent
separately
- dropped the RFC prefix
Changes since RFC v1 at [1]:
- add support for the timing adjustment clock input (dt-bindings and
in the driver) thanks to the input from the unnamed Ethernet engineer
at Amlogic. This is the missing link between the fclk_div2 clock and
the Ethernet controller on Meson8b (no traffic would flow if that
clock was disabled)
- add support fot the amlogic,rx-delay-ns property. The only supported
values so far are 0ns and 2ns. The registers seem to allow more
precise timing adjustments, but I could not make that work so far.
- add more register documentation (for the new RX delay bits) and
unified the placement of existing register documentation. Again,
thanks to Jianxin and the unnamed Ethernet engineer at Amlogic
- DO NOT MERGE: .dts patches to show the conversion of the Meson8b
and Meson8m2 boards to "rgmii-id". I didn't have time for all arm64
patches yet, but these will switch to phy-mode = "rgmii-txid" with
amlogic,rx-delay-ns = <0> (because the delay seems to be provided by
the PCB trace length).
[0] https://patchwork.kernel.org/patch/11309891/
[1] https://patchwork.kernel.org/cover/11310719/
[2] https://patchwork.kernel.org/cover/11518257/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Configure the PRG_ETH0_ADJ_* bits to enable or disable the RX delay
based on the various RGMII PHY modes. For now the only supported RX
delay settings are:
- disabled, use for example for phy-mode "rgmii-id"
- 0ns - this is treated identical to "disabled", used for example on
boards where the PHY provides 2ns TX delay and the PCB trace length
already adds 2ns RX delay
- 2ns - for whenever the PHY cannot add the RX delay and the traces on
the PCB don't add any RX delay
Disabling the RX delay (in case u-boot enables it, which is the case
for example on Meson8b Odroid-C1) simply means that PRG_ETH0_ADJ_ENABLE,
PRG_ETH0_ADJ_SETUP, PRG_ETH0_ADJ_DELAY and PRG_ETH0_ADJ_SKEW should be
disabled (just disabling PRG_ETH0_ADJ_ENABLE may be enough, since that
disables the whole re-timing logic - but I find it makes more sense to
clear the other bits as well since they depend on that setting).
u-boot on Odroid-C1 uses the following steps to enable a 2ns RX delay:
- enabling enabling the timing adjustment clock
- enabling the timing adjustment logic by setting PRG_ETH0_ADJ_ENABLE
- setting the PRG_ETH0_ADJ_SETUP bit
The documentation for the PRG_ETH0_ADJ_DELAY and PRG_ETH0_ADJ_SKEW
registers indicates that we can even set different RX delays. However,
I could not find out how this works exactly, so for now we only support
a 2ns RX delay using the exact same way that Odroid-C1's u-boot does.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The timing adjustment clock will need similar logic as the RGMII clock:
It has to be enabled in the driver conditionally and when the driver is
unloaded it should be disabled again. Extract the existing code for the
RGMII clock into a new function so it can be re-used.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PRG_ETHERNET registers have a built-in timing adjustment circuit
which can provide the RX delay in RGMII mode. This is driven by an
external (to this IP, but internal to the SoC) clock input. Fetch this
clock as optional (even though it's there on all supported SoCs) since
we just learned about it and existing .dtbs don't specify it.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PRG_ETH0_ADJ_* are used for applying the RGMII RX delay. The public
datasheets only have very limited description for these registers, but
Jianxin Pan provided more detailed documentation from an (unnamed)
Amlogic engineer. Add the PRG_ETH0_ADJ_* bits along with the improved
description.
Suggested-by: Jianxin Pan <jianxin.pan@amlogic.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the documentation for the TX delay above the PRG_ETH0_TXDLY_MASK
definition. Future commits will add more registers also with
documentation above their register bit definitions. Move the existing
comment so it will be consistent with the upcoming changes.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use FIELD_PREP() to shift a value to the correct offset based on a
bitmask instead of open-coding the logic.
No functional changes.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PRG_ETHERNET registers can add an RX delay in RGMII mode. This
requires an internal re-timing circuit whose input clock is called
"timing adjustment clock". Document this clock input so the clock can be
enabled as needed.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PRG_ETHERNET registers on Meson8b and newer SoCs can add an RX
delay. Add a property with the known supported values so it can be
configured according to the board layout.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johan Hedberg says:
====================
pull request: bluetooth-next 2020-05-13
Here's a second attempt at a bluetooth-next pull request which
supercedes the one dated 2020-05-09. This should have the issues
discovered by Jakub fixed.
- Add support for Intel Typhoon Peak device (8087:0032)
- Add device tree bindings for Realtek RTL8723BS device
- Add device tree bindings for Qualcomm QCA9377 device
- Add support for experimental features configuration through mgmt
- Add driver hook to prevent wake from suspend
- Add support for waiting for L2CAP disconnection response
- Multiple fixes & cleanups to the btbcm driver
- Add support for LE scatternet topology for selected devices
- A few other smaller fixes & cleanups
Please let me know if there are any issues pulling. Thanks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrii Nakryiko says:
====================
Add generic benchmark runner framework which simplifies writing various
performance benchmarks in a consistent fashion. This framework will be used
in follow up patches to test performance of perf buffer and ring buffer as
well.
Patch #1 extracts parse_num_list to be re-used between test_progs and bench.
Patch #2 adds generic runner implementation and atomic counter benchmarks to
validate benchmark runner's behavior.
Patch #3 implements test_overhead benchmark as part of bench runner. It also
add fmod_ret BPF program type to a set of benchmarks.
Patch #4 tests faster alternatives to set_task_comm() approach, tested in
test_overhead, in search for minimal-overhead way to trigger BPF program
execution from user-space on demand.
v2->v3:
- added --prod-affinity and --cons-affinity (Yonghong);
- removed ringbuf-related options leftovers (Yonghong);
- added more benchmarking results for test_overhead performance discrepancies;
v1->v2:
- moved benchmarks into benchs/ subdir (John);
- added benchmark "suite" scripts (John);
- few small clean ups, change defaults, etc.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
It is sometimes desirable to be able to trigger BPF program from user-space
with minimal overhead. sys_enter would seem to be a good candidate, yet in
a lot of cases there will be a lot of noise from syscalls triggered by other
processes on the system. So while searching for low-overhead alternative, I've
stumbled upon getpgid() syscall, which seems to be specific enough to not
suffer from accidental syscall by other apps.
This set of benchmarks compares tp, raw_tp w/ filtering by syscall ID, kprobe,
fentry and fmod_ret with returning error (so that syscall would not be
executed), to determine the lowest-overhead way. Here are results on my
machine (using benchs/run_bench_trigger.sh script):
base : 9.200 ± 0.319M/s
tp : 6.690 ± 0.125M/s
rawtp : 8.571 ± 0.214M/s
kprobe : 6.431 ± 0.048M/s
fentry : 8.955 ± 0.241M/s
fmodret : 8.903 ± 0.135M/s
So it seems like fmodret doesn't give much benefit for such lightweight
syscall. Raw tracepoint is pretty decent despite additional filtering logic,
but it will be called for any other syscall in the system, which rules it out.
Fentry, though, seems to be adding the least amoung of overhead and achieves
97.3% of performance of baseline no-BPF-attached syscall.
Using getpgid() seems to be preferable to set_task_comm() approach from
test_overhead, as it's about 2.35x faster in a baseline performance.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200512192445.2351848-5-andriin@fb.com
Add fmod_ret BPF program to existing test_overhead selftest. Also re-implement
user-space benchmarking part into benchmark runner to compare results. Results
with ./bench are consistently somewhat lower than test_overhead's, but relative
performance of various types of BPF programs stay consisten (e.g., kretprobe is
noticeably slower). This slowdown seems to be coming from the fact that
test_overhead is single-threaded, while benchmark always spins off at least
one thread for producer. This has been confirmed by hacking multi-threaded
test_overhead variant and also single-threaded bench variant. Resutls are
below. run_bench_rename.sh script from benchs/ subdirectory was used to
produce results for ./bench.
Single-threaded implementations
===============================
/* bench: single-threaded, atomics */
base : 4.622 ± 0.049M/s
kprobe : 3.673 ± 0.052M/s
kretprobe : 2.625 ± 0.052M/s
rawtp : 4.369 ± 0.089M/s
fentry : 4.201 ± 0.558M/s
fexit : 4.309 ± 0.148M/s
fmodret : 4.314 ± 0.203M/s
/* selftest: single-threaded, no atomics */
task_rename base 4555K events per sec
task_rename kprobe 3643K events per sec
task_rename kretprobe 2506K events per sec
task_rename raw_tp 4303K events per sec
task_rename fentry 4307K events per sec
task_rename fexit 4010K events per sec
task_rename fmod_ret 3984K events per sec
Multi-threaded implementations
==============================
/* bench: multi-threaded w/ atomics */
base : 3.910 ± 0.023M/s
kprobe : 3.048 ± 0.037M/s
kretprobe : 2.300 ± 0.015M/s
rawtp : 3.687 ± 0.034M/s
fentry : 3.740 ± 0.087M/s
fexit : 3.510 ± 0.009M/s
fmodret : 3.485 ± 0.050M/s
/* selftest: multi-threaded w/ atomics */
task_rename base 3872K events per sec
task_rename kprobe 3068K events per sec
task_rename kretprobe 2350K events per sec
task_rename raw_tp 3731K events per sec
task_rename fentry 3639K events per sec
task_rename fexit 3558K events per sec
task_rename fmod_ret 3511K events per sec
/* selftest: multi-threaded, no atomics */
task_rename base 3945K events per sec
task_rename kprobe 3298K events per sec
task_rename kretprobe 2451K events per sec
task_rename raw_tp 3718K events per sec
task_rename fentry 3782K events per sec
task_rename fexit 3543K events per sec
task_rename fmod_ret 3526K events per sec
Note that the fact that ./bench benchmark always uses atomic increments for
counting, while test_overhead doesn't, doesn't influence test results all that
much.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200512192445.2351848-4-andriin@fb.com
While working on BPF ringbuf implementation, testing, and benchmarking, I've
developed a pretty generic and modular benchmark runner, which seems to be
generically useful, as I've already used it for one more purpose (testing
fastest way to trigger BPF program, to minimize overhead of in-kernel code).
This patch adds generic part of benchmark runner and sets up Makefile for
extending it with more sets of benchmarks.
Benchmarker itself operates by spinning up specified number of producer and
consumer threads, setting up interval timer sending SIGALARM signal to
application once a second. Every second, current snapshot with hits/drops
counters are collected and stored in an array. Drops are useful for
producer/consumer benchmarks in which producer might overwhelm consumers.
Once test finishes after given amount of warm-up and testing seconds, mean and
stddev are calculated (ignoring warm-up results) and is printed out to stdout.
This setup seems to give consistent and accurate results.
To validate behavior, I added two atomic counting tests: global and local.
For global one, all the producer threads are atomically incrementing same
counter as fast as possible. This, of course, leads to huge drop of
performance once there is more than one producer thread due to CPUs fighting
for the same memory location.
Local counting, on the other hand, maintains one counter per each producer
thread, incremented independently. Once per second, all counters are read and
added together to form final "counting throughput" measurement. As expected,
such setup demonstrates linear scalability with number of producers (as long
as there are enough physical CPU cores, of course). See example output below.
Also, this setup can nicely demonstrate disastrous effects of false sharing,
if care is not taken to take those per-producer counters apart into
independent cache lines.
Demo output shows global counter first with 1 producer, then with 4. Both
total and per-producer performance significantly drop. The last run is local
counter with 4 producers, demonstrating near-perfect scalability.
$ ./bench -a -w1 -d2 -p1 count-global
Setting up benchmark 'count-global'...
Benchmark 'count-global' started.
Iter 0 ( 24.822us): hits 148.179M/s (148.179M/prod), drops 0.000M/s
Iter 1 ( 37.939us): hits 149.308M/s (149.308M/prod), drops 0.000M/s
Iter 2 (-10.774us): hits 150.717M/s (150.717M/prod), drops 0.000M/s
Iter 3 ( 3.807us): hits 151.435M/s (151.435M/prod), drops 0.000M/s
Summary: hits 150.488 ± 1.079M/s (150.488M/prod), drops 0.000 ± 0.000M/s
$ ./bench -a -w1 -d2 -p4 count-global
Setting up benchmark 'count-global'...
Benchmark 'count-global' started.
Iter 0 ( 60.659us): hits 53.910M/s ( 13.477M/prod), drops 0.000M/s
Iter 1 (-17.658us): hits 53.722M/s ( 13.431M/prod), drops 0.000M/s
Iter 2 ( 5.865us): hits 53.495M/s ( 13.374M/prod), drops 0.000M/s
Iter 3 ( 0.104us): hits 53.606M/s ( 13.402M/prod), drops 0.000M/s
Summary: hits 53.608 ± 0.113M/s ( 13.402M/prod), drops 0.000 ± 0.000M/s
$ ./bench -a -w1 -d2 -p4 count-local
Setting up benchmark 'count-local'...
Benchmark 'count-local' started.
Iter 0 ( 23.388us): hits 640.450M/s (160.113M/prod), drops 0.000M/s
Iter 1 ( 2.291us): hits 605.661M/s (151.415M/prod), drops 0.000M/s
Iter 2 ( -6.415us): hits 607.092M/s (151.773M/prod), drops 0.000M/s
Iter 3 ( -1.361us): hits 601.796M/s (150.449M/prod), drops 0.000M/s
Summary: hits 604.849 ± 2.739M/s (151.212M/prod), drops 0.000 ± 0.000M/s
Benchmark runner supports setting thread affinity for producer and consumer
threads. You can use -a flag for default CPU selection scheme, where first
consumer gets CPU #0, next one gets CPU #1, and so on. Then producer threads
pick up next CPU and increment one-by-one as well. But user can also specify
a set of CPUs independently for producers and consumers with --prod-affinity
1,2-10,15 and --cons-affinity <set-of-cpus>. The latter allows to force
producers and consumers to share same set of CPUs, if necessary.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200512192445.2351848-3-andriin@fb.com
Add testing_helpers.c, which will contain generic helpers for test runners and
tests needing some common generic functionality, like parsing a set of
numbers.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200512192445.2351848-2-andriin@fb.com
Ursula Braun says:
====================
s390/net: updates 2020-05-13
please apply the fix from Wei Yongjun to netdev's net tree and
add Karsten Graul as co-maintainer for drivers/s390/net.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Add Karsten as additional maintainer for drivers/s390/net .
One of his focal points is the ism driver.
Cc: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix to return negative error code -ENOMEM from the smcd_alloc_dev()
error handling case instead of 0, as done elsewhere in this function.
Fixes: 684b89bc39 ("s390/ism: add device driver for internal shared memory")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since there can only be one of in_fence/exec_fence, just use the single
in_fence local.
v2: Consolidate lookup
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513180937.28992-1-chris@chris-wilson.co.uk
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
The output buffer used in mlx5_cmd_exec_inout() was wrongly changed from
pre-allocated srq_out pointer to an input "out" point. That leads to
unpredictable results in the get_srqc() call later.
Fixes: 31578defe4 ("RDMA/mlx5: Update mlx5_ib to use new cmd interface")
Link: https://lore.kernel.org/r/20200513100809.246315-1-leon@kernel.org
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
