kernel/linux.git/include/linux/dim.h, branch v6.12.80

dim: add new interfaces for initialization and getting results

2024-06-26T00:15:06+00:00

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 Reviewed-by: Simon Horman Link: https://patch.msgid.link/20240621101353.107425-5-hengqi@linux.alibaba.com Signed-off-by: Jakub Kicinski

ethtool: provide customized dim profile management

2024-06-26T00:15:06+00:00

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 Reviewed-by: Simon Horman Link: https://patch.msgid.link/20240621101353.107425-4-hengqi@linux.alibaba.com Signed-off-by: Jakub Kicinski

linux/dim: move useful macros to .h file

2024-06-26T00:15:06+00:00

Useful macros will be used effectively elsewhere. These will be utilized in subsequent patches. Signed-off-by: Heng Qi Reviewed-by: Simon Horman Link: https://patch.msgid.link/20240621101353.107425-2-hengqi@linux.alibaba.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 divide by 0 in RDMA DIM

2022-06-28T13:37:25+00:00

Fix a divide 0 error in rdma_dim_stats_compare() when prev->cpe_ratio == 0. CallTrace: Hardware name: H3C R4900 G3/RS33M2C9S, BIOS 2.00.37P21 03/12/2020 task: ffff880194b78000 task.stack: ffffc90006714000 RIP: 0010:backport_rdma_dim+0x10e/0x240 [mlx_compat] RSP: 0018:ffff880c10e83ec0 EFLAGS: 00010202 RAX: 0000000000002710 RBX: ffff88096cd7f780 RCX: 0000000000000064 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000000001d7c6c09 R13: ffff88096cd7f780 R14: ffff880b174fe800 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff880c10e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000a0965b00 CR3: 000000000200a003 CR4: 00000000007606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: ib_poll_handler+0x43/0x80 [ib_core] irq_poll_softirq+0xae/0x110 __do_softirq+0xd1/0x28c irq_exit+0xde/0xf0 do_IRQ+0x54/0xe0 common_interrupt+0x8f/0x8f ? cpuidle_enter_state+0xd9/0x2a0 ? cpuidle_enter_state+0xc7/0x2a0 ? do_idle+0x170/0x1d0 ? cpu_startup_entry+0x6f/0x80 ? start_secondary+0x1b9/0x210 ? secondary_startup_64+0xa5/0xb0 Code: 0f 87 e1 00 00 00 8b 4c 24 14 44 8b 43 14 89 c8 4d 63 c8 44 29 c0 99 31 d0 29 d0 31 d2 48 98 48 8d 04 80 48 8d 04 80 48 c1 e0 02 <49> f7 f1 48 83 f8 0a 0f 86 c1 00 00 00 44 39 c1 7f 10 48 89 df RIP: backport_rdma_dim+0x10e/0x240 [mlx_compat] RSP: ffff880c10e83ec0 Fixes: f4915455dcf0 ("linux/dim: Implement RDMA adaptive moderation (DIM)") Link: https://lore.kernel.org/r/20220627140004.3099-1-thomas.liu@ucloud.cn Signed-off-by: Tao Liu Reviewed-by: Max Gurtovoy Acked-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

DIM: fix dim.h kernel-doc and headers

2019-10-10T02:33:43+00:00

Lots of fixes to kernel-doc in structs, enums, and functions. Also add header files that are being used but not yet #included. Signed-off-by: Randy Dunlap Cc: Yamin Friedman Cc: Tal Gilboa Cc: Saeed Mahameed Cc: Doug Ledford Cc: Jason Gunthorpe Cc: linux-rdma@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Jakub Kicinski

lib/dim: Fix -Wunused-const-variable warnings

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

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 Reviewed-by: Bart Van Assche Acked-by: Saeed Mahameed Signed-off-by: David S. Miller

RDMA/core: Fix -Wunused-const-variable warnings

2019-07-11T14:49:55+00:00

The commit below introduced a few compilation warnings. 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 drivers/net/ethernet/mellanox/mlx5/core/uar.c:36: ./include/linux/dim.h:378:1: warning: 'rdma_dim_prof' defined but not used [-Wunused-const-variable=] rdma_dim_prof[RDMA_DIM_PARAMS_NUM_PROFILES] = { ^~~~~~~~~~~~~ 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 drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:37: ./include/linux/dim.h:378:1: warning: 'rdma_dim_prof' defined but not used [-Wunused-const-variable=] rdma_dim_prof[RDMA_DIM_PARAMS_NUM_PROFILES] = { ^~~~~~~~~~~~~ Since only ib_cq_rdma_dim_work() in drivers/infiniband/core/cq.c uses it, just move the definition over there. Fixes: f4915455dcf0 ("linux/dim: Implement RDMA adaptive moderation (DIM)") Signed-off-by: Qian Cai Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

linux/dim: Implement RDMA adaptive moderation (DIM)

2019-07-08T19:37:21+00:00

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 Reviewed-by: Max Gurtovoy Reviewed-by: Sagi Grimberg Signed-off-by: Saeed Mahameed Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

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