summaryrefslogtreecommitdiff
path: root/lib/dim
AgeCommit message (Collapse)Author
2023-05-09linux/dim: Do nothing if no time delta between samplesRoy Novich
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>
2022-05-09dim: initialize all struct fieldsJesse Brandeburg
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 Desaulniers
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>
2020-08-24lib: Revert use of fallthrough pseudo-keyword in lib/Gustavo A. R. Silva
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>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
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 Romanovsky
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 Friedman
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 Friedman
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 Friedman
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 Gilboa
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>