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The imm_inval_pkey field can hold four different types of data,
depends on the usage, the data could be one of the below:
- Immediate field of the received message
- Invalidate rkey
- Pkey of the packet
- Flow table metadata
Current implementation doesn't reflect the intended usage of the
field at usage time.
Reflect the different types by replace this field with a union,
modify code where this field is used to reflect its intended
usage.
Signed-off-by: Raed Salem <raeds@mellanox.com>
Reviewed-by: Huy Nguyen <huyn@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
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The alignment value is part of the input structure, so use it and spare
extra memory allocation when is not needed.
Now, using the new ability when allocating icm for Direct-Rule
insertion.
Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Signed-off-by: Erez Shitrit <erezsh@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
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Add IPsec offload related IFC structs, layouts and enumerations.
Signed-off-by: Raed Salem <raeds@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
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Add COPY type to modify_header action. IPsec feature is the first
feature that needs COPY steering action.
Signed-off-by: Huy Nguyen <huyn@mellanox.com>
Signed-off-by: Raed Salem <raeds@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
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ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull in Christoph Hellwig's series that changes the sysctl's ->proc_handler
methods to take kernel pointers instead. It gets rid of the set_fs address
space overrides used by BPF. As per discussion, pull in the feature branch
into bpf-next as it relates to BPF sysctl progs.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200427071508.GV23230@ZenIV.linux.org.uk/T/
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It's currently the amba driver's responsibility to initialize the pointer,
dma_parms, for its corresponding struct device. The benefit with this
approach allows us to avoid the initialization and to not waste memory for
the struct device_dma_parameters, as this can be decided on a case by case
basis.
However, it has turned out that this approach is not very practical. Not
only does it lead to open coding, but also to real errors. In principle
callers of dma_set_max_seg_size() doesn't check the error code, but just
assumes it succeeds.
For these reasons, let's do the initialization from the common amba bus at
the device registration point. This also follows the way the PCI devices
are being managed, see pci_device_add().
Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Tested-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200422101013.31267-1-ulf.hansson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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It's currently the platform driver's responsibility to initialize the
pointer, dma_parms, for its corresponding struct device. The benefit with
this approach allows us to avoid the initialization and to not waste memory
for the struct device_dma_parameters, as this can be decided on a case by
case basis.
However, it has turned out that this approach is not very practical. Not
only does it lead to open coding, but also to real errors. In principle
callers of dma_set_max_seg_size() doesn't check the error code, but just
assumes it succeeds.
For these reasons, let's do the initialization from the common platform bus
at the device registration point. This also follows the way the PCI devices
are being managed, see pci_device_add().
Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Tested-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200422100954.31211-1-ulf.hansson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add sysfs interface to set boot health status from user space.
Add API used by this interface to communicate with firmware.
If PMUFW is compiled with CHECK_HEALTHY_BOOT, it will check the
healthy bit on FPD WDT expiration. If healthy bit is set by a user
application running in Linux, PMUFW will do APU only restart. If
healthy bit is not set during FPD WDT expiration, PMUFW will do
system restart.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-26-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The Linux shutdown functionality implemented via PSCI system_off does
not include an option to set a scope, i.e. which parts of the system to
shut down.
This patch creates sysfs that allows to set the shutdown scope for the
next shutdown request. When the next shutdown is performed, the platform
specific portion of PSCI-system_off can use the chosen shutdown scope.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Stefan Krsmanovic <stefan.krsmanovic@aggios.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-25-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add system shutdown API interface which asks firmware to
perform system shutdown/restart.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-24-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add firmware-ggs sysfs interface which provides read/write
interface to global storage registers.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-23-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add APIs to read/write PGGS and GGS registers.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-22-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for fpga related
APIs. Also remove eemi ops structure.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-21-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call for aes engine instead of using eemi ops.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-20-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for
set_requirement.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-19-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for release_node.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-18-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for request_node.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-17-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of eemi ops for set_suspend_mode.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-16-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of eemi ops for init_finalize.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-15-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for
reset_get_status.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-14-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for
reset_assert.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-13-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Remove IOCTL API and use individual APIs for better readability.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-12-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of eemi ops for clock set/get parent.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-11-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of eemi ops for clock set/get rate.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-10-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for
clock_getdivider.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-9-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of using eemi ops for
clock_setdivider.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-8-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of eemi ops for clock_getstate.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-7-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call for clock_disable instead using of eemi ops.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-6-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call for clock_enable instead of eemi ops.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-5-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call for query_data instead of using eemi ops.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-4-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function call instead of eemi ops for get_chipid.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-3-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use direct function calls instead of using eemi ops. So remove
eemi ops for get_api_version and use direct function call.
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-2-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The Intel service layer driver has defined error codes for the
specific services, which started from FPGA configuration then RSU
(Remote Status Update).
Intel service layer driver should define the standard error codes
rather than keep adding more error codes for the new services.
The standard error codes will be used by all the clients of Intel service
layer driver.
Replace FPGA and RSU specific error codes with Intel service layer’s
Common error codes.
Signed-off-by: Richard Gong <richard.gong@intel.com>
Link: https://lore.kernel.org/r/1586897274-307-2-git-send-email-richard.gong@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add support for MHI suspend and resume states. While at it, the
mhi_notify() function needs to be exported as well.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200427075829.9304-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When testing whether or not to enable the use of the SMMU, consult the
supported DMA mask rather than the actually configured DMA mask, since
the latter might already have been restricted.
Fixes: 2d9384ff9177 ("drm/tegra: Relax IOMMU usage criteria on old Tegra")
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
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This structure is only really used in tboot.c. The only exception
is a single tboot_enabled check, but for that we don't need an inline
function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200428051703.1625952-1-hch@lst.de
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When adding the 'spimem' field to 'struct spi_nor', a grammar mistake
("point" instead of "pointer") was made -- fix it and convert the SPI
acronym to uppercase and fully spell out "memory", while at it...
Fixes: b35b9a10362 ("mtd: spi-nor: Move m25p80 code in spi-nor.c")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
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When adding the 'info' field to 'struct spi_nor', some acronyms were in
lower case and some in upper case and the JEDEC acronym mistyped -- fix
these issues.
Fixes: 46dde01f6bab ("mtd: spi-nor: add spi_nor_init() function")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
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When adding the '{read|write|reg}_proto' fields to 'struct spi_nor', a
colon was missed in the comment for the spi_nor::reg_proto' -- add it.
Fixes: cfc5604c488c ("mtd: spi-nor: introduce SPI 1-2-2 and SPI 1-4-4 protocols")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
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When embedding 'struct mtd_info' within 'struct spi_nor', the kernel-doc
comment was forgotten. Fix it by dropping the "pointer to" part from the
comment.
Fixes: 1976367173a4 ("mtd: spi-nor: embed struct mtd_info within struct spi_nor")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
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When introducing 'struct spi_nor', a number of issues was added in its
kernel-doc comment:
- double article in the heading kernel-doc comment;
- "point" instead of "pointer" for the 'mtd' and 'dev' fields;
- "a" articles instead of "an" for the 'dev' field;
- acronyms in the lower case for the 'dev' field;
- missing "pointer to" for the 'priv' field.
Fix all of those at once...
Fixes: 6e602ef73334 ("mtd: spi-nor: add the basic data structures")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
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Users can use devm version of of_icc_get() to benefit from automatic
resource release.
Signed-off-by: Akash Asthana <akashast@codeaurora.org>
Reviewed by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1586946198-13912-2-git-send-email-akashast@codeaurora.org
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
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To integrate MRP into the bridge, first the bridge needs to be aware of ports
that are part of an MRP ring and which rings are on the bridge.
Therefore extend bridge interface with the following:
- add new flag(BR_MPP_AWARE) to the net bridge ports, this bit will be
set when the port is added to an MRP instance. In this way it knows if
the frame was received on MRP ring port
- add new flag(BR_MRP_LOST_CONT) to the net bridge ports, this bit will be set
when the port lost the continuity of MRP Test frames.
- add a list of MRP instances
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When using -Wextra, gcc complains about torture_preempt_schedule()
when its definition is empty (i.e., when CONFIG_PREEMPTION is not
set/enabled). Fix these warnings by adding an empty do-while block
for that macro when CONFIG_PREEMPTION is not set.
Fixes these build warnings:
../kernel/locking/locktorture.c:119:29: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../kernel/locking/locktorture.c:166:29: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../kernel/locking/locktorture.c:337:29: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../kernel/locking/locktorture.c:490:29: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../kernel/locking/locktorture.c:528:29: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../kernel/locking/locktorture.c:553:29: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
I have verified that there is no object code change (with gcc 7.5.0).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: "Paul E. McKenney" <paulmck@kernel.org>
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This commit provides a new TASKS_TRACE_RCU_READ_MB Kconfig option that
enables use of read-side memory barriers by both rcu_read_lock_trace()
and rcu_read_unlock_trace() when the are executed with the
current->trc_reader_special.b.need_mb flag set. This flag is currently
never set. Doing that is the subject of a later commit.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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This commit splits ->trc_reader_need_end by using the rcu_special union.
This change permits readers to check to see if a memory barrier is
required without any added overhead in the common case where no such
barrier is required. This commit also adds the read-side checking.
Later commits will add the machinery to properly set the new
->trc_reader_special.b.need_mb field.
This commit also makes rcu_read_unlock_trace_special() tolerate nested
read-side critical sections within interrupt and NMI handlers.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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This commit makes the calls to rcu_tasks_qs() detect and report
quiescent states for RCU tasks trace. If the task is in a quiescent
state and if ->trc_reader_checked is not yet set, the task sets its own
->trc_reader_checked. This will cause the grace-period kthread to
remove it from the holdout list if it still remains there.
[ paulmck: Fix conditional compilation per kbuild test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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Because RCU does not watch exception early-entry/late-exit, idle-loop,
or CPU-hotplug execution, protection of tracing and BPF operations is
needlessly complicated. This commit therefore adds a variant of
Tasks RCU that:
o Has explicit read-side markers to allow finite grace periods in
the face of in-kernel loops for PREEMPT=n builds. These markers
are rcu_read_lock_trace() and rcu_read_unlock_trace().
o Protects code in the idle loop, exception entry/exit, and
CPU-hotplug code paths. In this respect, RCU-tasks trace is
similar to SRCU, but with lighter-weight readers.
o Avoids expensive read-side instruction, having overhead similar
to that of Preemptible RCU.
There are of course downsides:
o The grace-period code can send IPIs to CPUs, even when those
CPUs are in the idle loop or in nohz_full userspace. This is
mitigated by later commits.
o It is necessary to scan the full tasklist, much as for Tasks RCU.
o There is a single callback queue guarded by a single lock,
again, much as for Tasks RCU. However, those early use cases
that request multiple grace periods in quick succession are
expected to do so from a single task, which makes the single
lock almost irrelevant. If needed, multiple callback queues
can be provided using any number of schemes.
Perhaps most important, this variant of RCU does not affect the vanilla
flavors, rcu_preempt and rcu_sched. The fact that RCU Tasks Trace
readers can operate from idle, offline, and exception entry/exit in no
way enables rcu_preempt and rcu_sched readers to do so.
The memory ordering was outlined here:
https://lore.kernel.org/lkml/20200319034030.GX3199@paulmck-ThinkPad-P72/
This effort benefited greatly from off-list discussions of BPF
requirements with Alexei Starovoitov and Andrii Nakryiko. At least
some of the on-list discussions are captured in the Link: tags below.
In addition, KCSAN was quite helpful in finding some early bugs.
Link: https://lore.kernel.org/lkml/20200219150744.428764577@infradead.org/
Link: https://lore.kernel.org/lkml/87mu8p797b.fsf@nanos.tec.linutronix.de/
Link: https://lore.kernel.org/lkml/20200225221305.605144982@linutronix.de/
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andriin@fb.com>
[ paulmck: Apply feedback from Steve Rostedt and Joel Fernandes. ]
[ paulmck: Decrement trc_n_readers_need_end upon IPI failure. ]
[ paulmck: Fix locking issue reported by rcutorture. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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This commit adds a "rude" variant of RCU-tasks that has as quiescent
states schedule(), cond_resched_tasks_rcu_qs(), userspace execution,
and (in theory, anyway) cond_resched(). In other words, RCU-tasks rude
readers are regions of code with preemption disabled, but excluding code
early in the CPU-online sequence and late in the CPU-offline sequence.
Updates make use of IPIs and force an IPI and a context switch on each
online CPU. This variant is useful in some situations in tracing.
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
[ paulmck: Apply EXPORT_SYMBOL_GPL() feedback from Qiujun Huang. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Apply review feedback from Steve Rostedt. ]
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This commit splits out generic processing from RCU-tasks-specific
processing in order to allow additional flavors to be added. It also
adds a def_bool TASKS_RCU_GENERIC to enable the common RCU-tasks
infrastructure code.
This is primarily, but not entirely, a code-movement commit.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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