kernel/linux.git/lib/dim/dim.c, branch v6.12.80

lib: Allow for the DIM library to be modular

2024-05-07T23:42:45+00:00

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 Reviewed-by: Alexander Lobakin Link: https://lore.kernel.org/r/20240506175040.410446-1-florian.fainelli@broadcom.com Signed-off-by: Jakub Kicinski

linux/dim: Do nothing if no time delta between samples

2023-05-09T09:06:45+00:00

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 Reviewed-by: Aya Levin Reviewed-by: Saeed Mahameed Signed-off-by: Tariq Toukan Reviewed-by: Leon Romanovsky Reviewed-by: Michal Kubiak Link: https://lore.kernel.org/r/20230507135743.138993-1-tariqt@nvidia.com Signed-off-by: Paolo Abeni

linux/dim: Fix overflow in dim calculation

2019-07-25T18:34:39+00:00

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 Signed-off-by: Leon Romanovsky Acked-by: Saeed Mahameed Signed-off-by: David S. Miller

linux/dim: Add completions count to dim_sample

2019-06-25T20:46:40+00:00

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 Reviewed-by: Max Gurtovoy Signed-off-by: Saeed Mahameed

linux/dim: Move implementation to .c files

2019-06-25T20:46:39+00:00

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 Signed-off-by: Saeed Mahameed