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2024-09-02dimlib: use *-y instead of *-objs in MakefileAndy Shevchenko1-1/+1
*-objs suffix is reserved rather for (user-space) host programs while usually *-y suffix is used for kernel drivers (although *-objs works for that purpose for now). Let's correct the old usages of *-objs in Makefiles. Link: https://lkml.kernel.org/r/20240821155140.611514-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Florian Fainelli <florian.fainelli@broadcom.com> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tal Gilboa <talgi@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-26dim: add new interfaces for initialization and getting resultsHeng Qi1-0/+68
DIM-related mode and work have been collected in one same place, so new interfaces are added to provide convenience. Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20240621101353.107425-5-hengqi@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-26ethtool: provide customized dim profile managementHeng Qi1-0/+70
The NetDIM library, currently leveraged by an array of NICs, delivers excellent acceleration benefits. Nevertheless, NICs vary significantly in their dim profile list prerequisites. Specifically, virtio-net backends may present diverse sw or hw device implementation, making a one-size-fits-all parameter list impractical. On Alibaba Cloud, the virtio DPU's performance under the default DIM profile falls short of expectations, partly due to a mismatch in parameter configuration. I also noticed that ice/idpf/ena and other NICs have customized profilelist or placed some restrictions on dim capabilities. Motivated by this, I tried adding new params for "ethtool -C" that provides a per-device control to modify and access a device's interrupt parameters. Usage ======== The target NIC is named ethx. Assume that ethx only declares support for rx profile setting (with DIM_PROFILE_RX flag set in profile_flags) and supports modification of usec and pkt fields. 1. Query the currently customized list of the device $ ethtool -c ethx ... rx-profile: {.usec = 1, .pkts = 256, .comps = n/a,}, {.usec = 8, .pkts = 256, .comps = n/a,}, {.usec = 64, .pkts = 256, .comps = n/a,}, {.usec = 128, .pkts = 256, .comps = n/a,}, {.usec = 256, .pkts = 256, .comps = n/a,} tx-profile: n/a 2. Tune $ ethtool -C ethx rx-profile 1,1,n_2,n,n_3,3,n_4,4,n_n,5,n "n" means do not modify this field. $ ethtool -c ethx ... rx-profile: {.usec = 1, .pkts = 1, .comps = n/a,}, {.usec = 2, .pkts = 256, .comps = n/a,}, {.usec = 3, .pkts = 3, .comps = n/a,}, {.usec = 4, .pkts = 4, .comps = n/a,}, {.usec = 256, .pkts = 5, .comps = n/a,} tx-profile: n/a 3. Hint If the device does not support some type of customized dim profiles, the corresponding "n/a" will display. If the "n/a" field is being modified, -EOPNOTSUPP will be reported. Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20240621101353.107425-4-hengqi@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-26linux/dim: move useful macros to .h fileHeng Qi1-6/+0
Useful macros will be used effectively elsewhere. These will be utilized in subsequent patches. Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20240621101353.107425-2-hengqi@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-08lib: Allow for the DIM library to be modularFlorian Fainelli2-2/+5
Allow the Dynamic Interrupt Moderation (DIM) library to be built as a module. This is particularly useful in an Android GKI (Google Kernel Image) configuration where everything is built as a module, including Ethernet controller drivers. Having to build DIMLIB into the kernel image with potentially no user is wasteful. Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20240506175040.410446-1-florian.fainelli@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-09linux/dim: Do nothing if no time delta between samplesRoy Novich3-4/+7
Add return value for dim_calc_stats. This is an indication for the caller if curr_stats was assigned by the function. Avoid using curr_stats uninitialized over {rdma/net}_dim, when no time delta between samples. Coverity reported this potential use of an uninitialized variable. Fixes: 4c4dbb4a7363 ("net/mlx5e: Move dynamic interrupt coalescing code to include/linux") Fixes: cb3c7fd4f839 ("net/mlx5e: Support adaptive RX coalescing") Signed-off-by: Roy Novich <royno@nvidia.com> Reviewed-by: Aya Levin <ayal@nvidia.com> Reviewed-by: Saeed Mahameed <saeedm@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Michal Kubiak <michal.kubiak@intel.com> Link: https://lore.kernel.org/r/20230507135743.138993-1-tariqt@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-05-10dim: initialize all struct fieldsJesse Brandeburg1-22/+22
The W=2 build pointed out that the code wasn't initializing all the variables in the dim_cq_moder declarations with the struct initializers. The net change here is zero since these structs were already static const globals and were initialized with zeros by the compiler, but removing compiler warnings has value in and of itself. lib/dim/net_dim.c: At top level: lib/dim/net_dim.c:54:9: warning: missing initializer for field ‘comps’ of ‘const struct dim_cq_moder’ [-Wmissing-field-initializers] 54 | NET_DIM_RX_EQE_PROFILES, | ^~~~~~~~~~~~~~~~~~~~~~~ In file included from lib/dim/net_dim.c:6: ./include/linux/dim.h:45:13: note: ‘comps’ declared here 45 | u16 comps; | ^~~~~ and repeats for the tx struct, and once you fix the comps entry then the cq_period_mode field needs the same treatment. Use the commonly accepted style to indicate to the compiler that we know what we're doing, and add a comma at the end of each struct initializer to clean up the issue, and use explicit initializers for the fields we are initializing which makes the compiler happy. While here and fixing these lines, clean up the code slightly with a fix for the super long lines by removing the word "_MODERATION" from a couple defines only used in this file. Fixes: f8be17b81d44 ("lib/dim: Fix -Wunused-const-variable warnings") Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Link: https://lore.kernel.org/r/20220507011038.14568-1-jesse.brandeburg@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-18Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"Nick Desaulniers2-3/+3
This reverts commit 6a9dc5fd6170 ("lib: Revert use of fallthrough pseudo-keyword in lib/") Now that we can build arch/powerpc/boot/ free of -Wimplicit-fallthrough, re-enable these fixes for lib/. Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Link: https://github.com/ClangBuiltLinux/linux/issues/236 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-25lib: Revert use of fallthrough pseudo-keyword in lib/Gustavo A. R. Silva2-3/+3
The following build error for powerpc64 was reported by Nathan Chancellor: "$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e KERNEL_XZ $ make -skj"$(nproc)" ARCH=powerpc CROSS_COMPILE=powerpc64le-linux- distclean powernv_defconfig zImage ... In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:234, from arch/powerpc/boot/decompress.c:38: arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c: In function 'dec_main': arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c:586:4: error: 'fallthrough' undeclared (first use in this function) 586 | fallthrough; | ^~~~~~~~~~~ This will end up affecting distribution configurations such as Debian and OpenSUSE according to my testing. I am not sure what the solution is, the PowerPC wrapper does not set -D__KERNEL__ so I am not sure that compiler_attributes.h can be safely included." In order to avoid these sort of problems, it seems that the best solution is to use /* fall through */ comments instead of the fallthrough pseudo-keyword macro in lib/, for now. Reported-by: Nathan Chancellor <natechancellor@gmail.com> Fixes: df561f6688fe ("treewide: Use fallthrough pseudo-keyword") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2-3/+3
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2019-07-25lib/dim: Fix -Wunused-const-variable warningsLeon Romanovsky1-0/+56
DIM causes to the following warnings during kernel compilation which indicates that tx_profile and rx_profile are supposed to be declared in *.c and not in *.h files. In file included from ./include/rdma/ib_verbs.h:64, from ./include/linux/mlx5/device.h:37, from ./include/linux/mlx5/driver.h:51, from ./include/linux/mlx5/vport.h:36, from drivers/infiniband/hw/mlx5/ib_virt.c:34: ./include/linux/dim.h:326:1: warning: _tx_profile_ defined but not used [-Wunused-const-variable=] 326 | tx_profile[DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = { | ^~~~~~~~~~ ./include/linux/dim.h:320:1: warning: _rx_profile_ defined but not used [-Wunused-const-variable=] 320 | rx_profile[DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = { | ^~~~~~~~~~ Fixes: 4f75da3666c0 ("linux/dim: Move implementation to .c files") Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Acked-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-25linux/dim: Fix overflow in dim calculationYamin Friedman1-2/+2
While using net_dim, a dim_sample was used without ever initializing the comps value. Added use of DIV_ROUND_DOWN_ULL() to prevent potential overflow, it should not be a problem to save the final result in an int because after the division by epms the value should not be larger than a few thousand. [ 1040.127124] UBSAN: Undefined behaviour in lib/dim/dim.c:78:23 [ 1040.130118] signed integer overflow: [ 1040.131643] 134718714 * 100 cannot be represented in type 'int' Fixes: 398c2b05bbee ("linux/dim: Add completions count to dim_sample") Signed-off-by: Yamin Friedman <yaminf@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Acked-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-08linux/dim: Implement RDMA adaptive moderation (DIM)Yamin Friedman2-4/+110
RDMA DIM implements a different algorithm from net DIM and is based on completions which is how we can implement interrupt moderation in RDMA. The algorithm optimizes for number of completions and ratio between completions and events. In order to avoid long latencies, the implementation performs fast reduction of moderation level when the traffic changes. Signed-off-by: Yamin Friedman <yaminf@mellanox.com> Reviewed-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-06-25linux/dim: Add completions count to dim_sampleYamin Friedman1-0/+9
Added a measurement of completions per/msec to allow for completion based dim algorithms. In order to use dynamic interrupt moderation with RDMA we need to have a different measurment than packets per second. This change is meant to prepare for adding a new DIM method. All drivers that use net_dim and thus do not need a completion count will have the completions set to 0. Signed-off-by: Yamin Friedman <yaminf@mellanox.com> Reviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2019-06-25linux/dim: Move implementation to .c filesTal Gilboa3-0/+273
Moved all logic from dim.h and net_dim.h to dim.c and net_dim.c. This is both more structurally appealing and would allow to only expose externally used functions. Signed-off-by: Tal Gilboa <talgi@mellanox.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>