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MLX5E_RX_ERR_CQE Macro is used only in data-path, move it to the
appropriate header file.
Signed-off-by: Eran Ben Elisha <eranbe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
SW group counter update function aggregates sw stats out of many
mlx5e_*_stats resides in a given mlx5e_channel_stats struct.
Split the function into a few helper functions.
This will be used later in the series to calculate specific
mlx5e_*_stats which are not defined inside mlx5e_channel_stats.
Signed-off-by: Eran Ben Elisha <eranbe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
The skb fifo push/pop API used pre-defined attributes within the
mlx5e_txqsq.
In order to share the skb fifo API with other non-SQ use cases,
change the API input to get newly defined mlx5e_skb_fifo struct.
Signed-off-by: Eran Ben Elisha <eranbe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
In order to be able to create an SQ outside of a channel context, remove
sq->channel direct pointer. This requires adding a direct pointer to:
netdevice, priv and mlx5_core in order to support SQs that are part of
mlx5e_channel. Use channel_stats from the corresponding CQ.
Signed-off-by: Eran Ben Elisha <eranbe@nvidia.com>
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
In order to be able to create an RQ outside of a channel context, remove
rq->channel direct pointer. This requires adding a direct pointer to:
ICOSQ and priv in order to support RQs that are part of mlx5e_channel.
Use channel_stats from the corresponding CQ.
Signed-off-by: Aya Levin <ayal@nvidia.com>
Signed-off-by: Eran Ben Elisha <eranbe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
In order to be able to create a CQ outside of a channel context, remove
cq->channel direct pointer. This requires adding a direct pointer to
channel statistics, netdevice, priv and to mlx5_core in order to support
CQs that are a part of mlx5e_channel.
In addition, parameters the were previously derived from the channel
like napi, NUMA node, channel stats and index are now assembled in
struct mlx5e_create_cq_param which is given to mlx5e_open_cq() instead
of channel pointer. Generalizing mlx5e_open_cq() allows opening CQ
outside of channel context which will be used in following patches in
the patch-set.
Signed-off-by: Aya Levin <ayal@nvidia.com>
Signed-off-by: Eran Ben Elisha <eranbe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
The drop RQ has very limited objects to be freed, and differs
from regular RQs in the context that it is freed from.
Add a dedicated function for it, use it where needed, and remove
the drop_rq-specific checks in the generic function.
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Saeed Mahameed says:
====================
mlx5-next auxbus support
This pull request is targeting net-next and rdma-next branches.
This series provides mlx5 support for auxiliary bus devices.
It starts with a merge commit of tag 'auxbus-5.11-rc1' from
gregkh/driver-core into mlx5-next, then the mlx5 patches that will convert
mlx5 ulp devices (netdev, rdma, vdpa) to use the proper auxbus
infrastructure instead of the internal mlx5 device and interface management
implementation, which Leon is deleting at the end of this patchset.
Link: https://lore.kernel.org/alsa-devel/20201026111849.1035786-1-leon@kernel.org/
Thanks to everyone for the joint effort !
* 'mlx5-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux:
RDMA/mlx5: Remove IB representors dead code
net/mlx5: Simplify eswitch mode check
net/mlx5: Delete custom device management logic
RDMA/mlx5: Convert mlx5_ib to use auxiliary bus
net/mlx5e: Connect ethernet part to auxiliary bus
vdpa/mlx5: Connect mlx5_vdpa to auxiliary bus
net/mlx5: Register mlx5 devices to auxiliary virtual bus
vdpa/mlx5: Make hardware definitions visible to all mlx5 devices
net/mlx5_core: Clean driver version and name
net/mlx5: Properly convey driver version to firmware
driver core: auxiliary bus: minor coding style tweaks
driver core: auxiliary bus: make remove function return void
driver core: auxiliary bus: move slab.h from include file
Add auxiliary bus support
====================
Link: https://lore.kernel.org/r/20201207053349.402772-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
All usages of the definition MAX_MSIX_P_PORT were removed.
It's not in use anymore. Remove it.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Moshe Shemesh <moshe@mellanox.com>
Link: https://lore.kernel.org/r/20201206091254.12476-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We can remove one of the ifdef blocks here, and instead of setting both
the xfrm hw_features and features flags, then unsetting the feature
flags if not in AB, wait to set the features flags if we're actually in AB
mode.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Link: https://lore.kernel.org/r/20201205174003.578267-1-jarod@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We sometimes run into situations where a soft/hard reset of the adapter
takes a long time or fails to complete. Having additional messages that
include important adapter state info will hopefully help understand what
is happening, reduce the guess work and minimize requests to reproduce
problems with debug patches.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Link: https://lore.kernel.org/r/20201205022235.2414110-1-sukadev@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Julian Wiedmann says:
====================
s390/qeth: updates 2020-12-07
please apply the following patch series for qeth to netdev's net-next tree.
Some sysfs cleanups (with the prep work in ccwgroup acked by Heiko), and
a few improvements to the code that deals with async TX completion
notifications for IQD devices.
This also brings the missing patch from the previous net-next submission.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When qeth_qdio_handle_aob() frees dangling allocations in the notified
TX buffer, there are rare tear-down cases where
qeth_drain_output_queue() would later call qeth_clear_output_buffer()
for the same buffer - and thus end up walking the buffer a second time
to check for dangling kmem_cache allocations.
Luckily current code previously scrubs such a buffer, so
qeth_clear_output_buffer() would find buf->buffer->element[i].addr as
NULL and not do anything. But this is fragile, and we can easily improve
it by consistently clearing the ->is_header flag after freeing the
allocation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reuse the QETH_QDIO_BUF_EMPTY state to indicate that a TX buffer has
been completed with a QAOB notification, and may be cleaned up by
qeth_cleanup_handled_pending().
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For TX buffers that require an additional async notification via QAOB, the
TX completion code can now manage all the necessary processing if the
notification has already occurred (or is occurring concurrently).
In such cases we can avoid replacing the metadata that is associated
with the buffer's slot on the ring, and just keep using the current one.
As qeth_clear_output_buffer() will also handle any kmem cache-allocated
memory that was mapped into the TX buffer, qeth_qdio_handle_aob()
doesn't need to worry about it.
While at it, also remove the unneeded forward declaration for
qeth_init_qdio_out_buf().
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All qeth devices have a minimum set of sysfs attributes, and non-OSN
devices share a group of additional attributes. Depending on whether
the device is forced to use a specific discipline, the device_type then
specifies further attributes.
Shift the common attributes into dev->groups, so that the device_type
only contains the discipline-specific attributes. This avoids exposing
the common attributes to the disciplines, and nicely cleans up our
sysfs code.
While replacing the qeth_l*_*_device_attributes() helpers, switch from
sysfs_*_groups() to the more generic device_*_groups().
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bus drivers have their own way of describing the sysfs attributes that
all devices on a bus should provide.
Switch ccwgroup_attr_groups over to use bus->dev_groups, and thus
free up dev->groups for usage by the ccwgroup device drivers.
While adjusting the attribute naming, use ATTRIBUTE_GROUPS() to get rid
of some boilerplate code.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
INIT_LIST_HEAD() only needs to be called on actual list heads.
While at it clarify the naming of the field.
Suggested-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ido Schimmel says:
====================
mlxsw: Misc updates
This patchset contains miscellaneous patches we gathered in our queue.
Some of them are dependencies of larger patchsets that I will submit
later this cycle.
Patches #1-#3 perform small non-functional changes in mlxsw.
Patch #4 adds more extended ack messages in mlxsw.
Patch #5 adds devlink parameters documentation for mlxsw. To be extended
with more parameters this cycle.
Patches #6-#7 perform small changes in forwarding selftests
infrastructure.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Turned out that mlxsw_sp_ipip_fib_entry_op_gre4() does not need to
figure out the IP address and virtual router id. Those are exactly
the same as in the fib_entry it is called for. So just use that and
reduce mlxsw_sp_ipip_fib_entry_op_gre4() function to only call
mlxsw_sp_ipip_fib_entry_op_gre4_rtdp() make the ipip decap op
code similar to nve.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The indicated version fixes an issue whereby the MOMTE register would by
default enable mirroring of ECN-marked traffic from all traffic classes,
once the ECN mirroring was configured. This fix is necessary for offload
of RED "ecn_mark" qevent.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Suppresses the following coccinelle warning:
drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_keys.c:139:3-7:
WARNING use flexible-array member instead
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Suppresses the following coccinelle warning:
drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:18:15-19: WARNING use flexible-array member instead
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, mlxsw triggers the 'devlink:devlink_hwmsg' tracepoint
whenever a request is sent to the device and whenever a response is
received from it. However, the tracepoint is not triggered when an event
(e.g., port up / down) is received from the device.
Also trace EMAD events in order to log a more complete picture of all
the exchanged hardware messages.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Test that the reference count of a router interface (RIF) configured for
a LAG is incremented / decremented when ports join / leave the LAG. Use
the offload indication on routes configured on the RIF to understand if
it was created / destroyed.
The test fails without the previous patch.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case a router interface (RIF) is configured for a LAG, make sure its
configuration is applied on the new LAG member.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Provide mlx5_core device instead of "priv" pointer while checking
eswith mode.
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
After conversion to use auxiliary bus, all custom device management is
not needed anymore, delete it.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
The conversion to auxiliary bus solves long standing issue with
existing mlx5_ib<->mlx5_core coupling. It required to have both
modules in initramfs if one of them needed for the boot.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Change module registration logic to use auxiliary bus instead of custom
made mlx5 register interface.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Heiner Kallweit says:
====================
r8169: improve rtl_rx and NUM_RX_DESC handling
This series improves rtl_rx() and the handling of NUM_RX_DESC.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
After recent changes there's no need any longer to define NUM_RX_DESC
as an unsigned value.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's no need to check min(budget, NUM_RX_DESC). At first budget
(NAPI_POLL_WEIGHT = 64) is less then NUM_RX_DESC (256).
And more important: Even in case of budget > NUM_RX_DESC we could
safely continue processing descriptors as long as they are owned by
the CPU. In addition replace rx_left with a normal counter variable,
this allows to simplify the code. Last but not least there's no need
any longer to pass the budget as an u32.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- bump version strings, by Simon Wunderlich
- update include for min/max helpers, by Sven Eckelmann
- add infrastructure and netlink functions for routing algo selection,
by Sven Eckelmann (2 patches)
- drop deprecated debugfs and sysfs support and obsoleted
functionality, by Sven Eckelmann (3 patches)
- drop unused include in fragmentation.c, by Simon Wunderlich
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Merge tag 'batadv-next-pullrequest-20201204' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
This cleanup patchset includes the following patches:
- bump version strings, by Simon Wunderlich
- update include for min/max helpers, by Sven Eckelmann
- add infrastructure and netlink functions for routing algo selection,
by Sven Eckelmann (2 patches)
- drop deprecated debugfs and sysfs support and obsoleted
functionality, by Sven Eckelmann (3 patches)
- drop unused include in fragmentation.c, by Simon Wunderlich
* tag 'batadv-next-pullrequest-20201204' of git://git.open-mesh.org/linux-merge:
batman-adv: Drop unused soft-interface.h include in fragmentation.c
batman-adv: Drop legacy code for auto deleting mesh interfaces
batman-adv: Drop deprecated debugfs support
batman-adv: Drop deprecated sysfs support
batman-adv: Allow selection of routing algorithm over rtnetlink
batman-adv: Prepare infrastructure for newlink settings
batman-adv: Add new include for min/max helpers
batman-adv: Start new development cycle
====================
Link: https://lore.kernel.org/r/20201204154631.21063-1-sw@simonwunderlich.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When CONFIG_OF is disabled, there is a harmless warning about
an unused variable:
enetc_pf.c: In function 'enetc_phylink_create':
enetc_pf.c:981:17: error: unused variable 'dev' [-Werror=unused-variable]
Slightly rearrange the code to pass around the of_node as a
function argument, which avoids the problem without hurting
readability.
Fixes: 71b77a7a27 ("enetc: Migrate to PHYLINK and PCS_LYNX")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Link: https://lore.kernel.org/r/20201204120800.17193-1-claudiu.manoil@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The OpenCompute time card is an atomic clock along with
a GPS receiver that provides a Grandmaster clock source
for a PTP enabled network.
More information is available at http://www.timingcard.com/
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Link: https://lore.kernel.org/r/20201204035128.2219252-2-jonathan.lemon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
implement the NCI 2.x initial sequence to support NCI 2.x NFCC.
Since NCI 2.0, CORE_RESET and CORE_INIT sequence have been changed.
If NFCEE supports NCI 2.x, then NCI 2.x initial sequence will work.
In NCI 1.0, Initial sequence and payloads are as below:
(DH) (NFCC)
| -- CORE_RESET_CMD --> |
| <-- CORE_RESET_RSP -- |
| -- CORE_INIT_CMD --> |
| <-- CORE_INIT_RSP -- |
CORE_RESET_RSP payloads are Status, NCI version, Configuration Status.
CORE_INIT_CMD payloads are empty.
CORE_INIT_RSP payloads are Status, NFCC Features,
Number of Supported RF Interfaces, Supported RF Interface,
Max Logical Connections, Max Routing table Size,
Max Control Packet Payload Size, Max Size for Large Parameters,
Manufacturer ID, Manufacturer Specific Information.
In NCI 2.0, Initial Sequence and Parameters are as below:
(DH) (NFCC)
| -- CORE_RESET_CMD --> |
| <-- CORE_RESET_RSP -- |
| <-- CORE_RESET_NTF -- |
| -- CORE_INIT_CMD --> |
| <-- CORE_INIT_RSP -- |
CORE_RESET_RSP payloads are Status.
CORE_RESET_NTF payloads are Reset Trigger,
Configuration Status, NCI Version, Manufacturer ID,
Manufacturer Specific Information Length,
Manufacturer Specific Information.
CORE_INIT_CMD payloads are Feature1, Feature2.
CORE_INIT_RSP payloads are Status, NFCC Features,
Max Logical Connections, Max Routing Table Size,
Max Control Packet Payload Size,
Max Data Packet Payload Size of the Static HCI Connection,
Number of Credits of the Static HCI Connection,
Max NFC-V RF Frame Size, Number of Supported RF Interfaces,
Supported RF Interfaces.
Signed-off-by: Bongsu Jeon <bongsu.jeon@samsung.com>
Link: https://lore.kernel.org/r/20201202223147.3472-1-bongsu.jeon@samsung.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Connect hosts H1 and H2 using two intermediate encapsulation routers
(LER1 and LER2). These routers encapsulate traffic from the hosts,
including the original Ethernet header, into MPLS.
Use ping to test reachability between H1 and H2.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Link: https://lore.kernel.org/r/625f5c1aafa3a8085f8d3e082d680a82e16ffbaa.1606918980.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We add the support to remove a specific node down with 128bit
node identifier, as an alternative to legacy 32-bit node address.
example:
$tipc peer remove identiy <1001002|16777777>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Link: https://lore.kernel.org/r/20201203035045.4564-1-hoang.h.le@dektech.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If there isn't a proper NFC firmware image, Bootloader mode will be
skipped.
Signed-off-by: Bongsu Jeon <bongsu.jeon@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201203225257.2446-1-bongsu.jeon@samsung.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Arjun Roy says:
====================
Perf. optimizations for TCP Recv. Zerocopy
This patchset contains several optimizations for TCP Recv. Zerocopy.
Summarized:
1. It is possible that a read payload is not exactly page aligned -
that there may exist "straggler" bytes that we cannot map into the
caller's address space cleanly. For this, we allow the caller to
provide as argument a "hybrid copy buffer", turning
getsockopt(TCP_ZEROCOPY_RECEIVE) into a "hybrid" operation that allows
the caller to avoid a subsequent recvmsg() call to read the
stragglers.
2. Similarly, for "small" read payloads that are either below the size
of a page, or small enough that remapping pages is not a performance
win - we allow the user to short-circuit the remapping operations
entirely and simply copy into the buffer provided.
Some of the patches in the middle of this set are refactors to support
this "short-circuiting" optimization.
3. We allow the user to provide a hint that performing a page zap
operation (and the accompanying TLB shootdown) may not be necessary,
for the provided region that the kernel will attempt to map pages
into. This allows us to avoid this expensive operation while holding
the socket lock, which provides a significant performance advantage.
With all of these changes combined, "medium" sized receive traffic
(multiple tens to few hundreds of KB) see significant efficiency gains
when using TCP receive zerocopy instead of regular recvmsg(). For
example, with RPC-style traffic with 32KB messages, there is a roughly
15% efficiency improvement when using zerocopy. Without these changes,
there is a roughly 60-70% efficiency reduction with such messages when
employing zerocopy.
====================
Link: https://lore.kernel.org/r/20201202225349.935284-1-arjunroy.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Zapping pages is required only if we are calling vm_insert_page into a
region where pages had previously been mapped. Receive zerocopy allows
reusing such regions, and hitherto called zap_page_range() before
calling vm_insert_page() in that range.
zap_page_range() can also be triggered from userspace with
madvise(MADV_DONTNEED). If userspace is configured to call this before
reusing a segment, or if there was nothing mapped at this virtual
address to begin with, we can avoid calling zap_page_range() under the
socket lock. That said, if userspace does not do that, then we are
still responsible for calling zap_page_range().
This patch adds a flag that the user can use to hint to the kernel
that a zap is not required. If the flag is not set, or if an older
user application does not have a flags field at all, then the kernel
calls zap_page_range as before. Also, if the flag is set but a zap is
still required, the kernel performs that zap as necessary. Thus
incorrectly indicating that a zap can be avoided does not change the
correctness of operation. It also increases the batchsize for
vm_insert_pages and prefetches the page struct for the batch since
we're about to bump the refcount.
An alternative mechanism could be to not have a flag, assume by
default a zap is not needed, and fall back to zapping if needed.
However, this would harm performance for older applications for which
a zap is necessary, and thus we implement it with an explicit flag
so newer applications can opt in.
When using RPC-style traffic with medium sized (tens of KB) RPCs, this
change yields an efficency improvement of about 30% for QPS/CPU usage.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Set zerocopy hint, event when falling back to copy, so that the
pending data can be efficiently received using zerocopy when
possible.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sometimes, we may call tcp receive zerocopy when inq is 0,
or inq < PAGE_SIZE, or inq is generally small enough that
it is cheaper to copy rather than remap pages.
In these cases, we may want to either return early (inq=0) or
attempt to use the provided copy buffer to simply copy
the received data.
This allows us to save both system call overhead and
the latency of acquiring mmap_sem in read mode for cases where
it would be useless to do so.
This patchset enables this behaviour by:
1. Returning quickly if inq is 0.
2. Attempting to perform a regular copy if a hybrid copybuffer is
provided and it is large enough to absorb all available bytes.
3. Return quickly if no such buffer was provided and there are less
than PAGE_SIZE bytes available.
For small RPC ping-pong workloads, normally we would have
1 getsockopt(), 1 recvmsg() and 1 sendmsg() call per RPC. With this
change, we remove the recvmsg() call entirely, reducing the syscall
overhead by about 33%. In testing with small (hundreds of bytes)
RPC traffic, this yields a syscall reduction of about 33% and
an efficiency gain of about 3-5% when defined as QPS/CPU Util.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sometimes, we may call tcp receive zerocopy when inq is 0,
or inq < PAGE_SIZE, in which case we cannot remap pages. In this case,
simply return the appropriate hint for regular copying without taking
mmap_sem.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>