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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-15 20:38:15 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-15 20:38:15 -0700 |
commit | 2a3c389a0fde49b241430df806a34276568cfb29 (patch) | |
tree | 9cf35829317e8cc2aaffc4341fb824dad63fce02 /lib/dim/rdma_dim.c | |
parent | 8de262531f5fbb7458463224a7587429800c24bf (diff) | |
parent | 0b043644c0ca601cb19943a81aa1f1455dbe9461 (diff) | |
download | linux-2a3c389a0fde49b241430df806a34276568cfb29.tar.bz2 |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull rdma updates from Jason Gunthorpe:
"A smaller cycle this time. Notably we see another new driver, 'Soft
iWarp', and the deletion of an ancient unused driver for nes.
- Revise and simplify the signature offload RDMA MR APIs
- More progress on hoisting object allocation boiler plate code out
of the drivers
- Driver bug fixes and revisions for hns, hfi1, efa, cxgb4, qib,
i40iw
- Tree wide cleanups: struct_size, put_user_page, xarray, rst doc
conversion
- Removal of obsolete ib_ucm chardev and nes driver
- netlink based discovery of chardevs and autoloading of the modules
providing them
- Move more of the rdamvt/hfi1 uapi to include/uapi/rdma
- New driver 'siw' for software based iWarp running on top of netdev,
much like rxe's software RoCE.
- mlx5 feature to report events in their raw devx format to userspace
- Expose per-object counters through rdma tool
- Adaptive interrupt moderation for RDMA (DIM), sharing the DIM core
from netdev"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (194 commits)
RMDA/siw: Require a 64 bit arch
RDMA/siw: Mark expected switch fall-throughs
RDMA/core: Fix -Wunused-const-variable warnings
rdma/siw: Remove set but not used variable 's'
rdma/siw: Add missing dependencies on LIBCRC32C and DMA_VIRT_OPS
RDMA/siw: Add missing rtnl_lock around access to ifa
rdma/siw: Use proper enumerated type in map_cqe_status
RDMA/siw: Remove unnecessary kthread create/destroy printouts
IB/rdmavt: Fix variable shadowing issue in rvt_create_cq
RDMA/core: Fix race when resolving IP address
RDMA/core: Make rdma_counter.h compile stand alone
IB/core: Work on the caller socket net namespace in nldev_newlink()
RDMA/rxe: Fill in wc byte_len with IB_WC_RECV_RDMA_WITH_IMM
RDMA/mlx5: Set RDMA DIM to be enabled by default
RDMA/nldev: Added configuration of RDMA dynamic interrupt moderation to netlink
RDMA/core: Provide RDMA DIM support for ULPs
linux/dim: Implement RDMA adaptive moderation (DIM)
IB/mlx5: Report correctly tag matching rendezvous capability
docs: infiniband: add it to the driver-api bookset
IB/mlx5: Implement VHCA tunnel mechanism in DEVX
...
Diffstat (limited to 'lib/dim/rdma_dim.c')
-rw-r--r-- | lib/dim/rdma_dim.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/lib/dim/rdma_dim.c b/lib/dim/rdma_dim.c new file mode 100644 index 000000000000..f7e26c7b4749 --- /dev/null +++ b/lib/dim/rdma_dim.c @@ -0,0 +1,108 @@ +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB +/* + * Copyright (c) 2019, Mellanox Technologies inc. All rights reserved. + */ + +#include <linux/dim.h> + +static int rdma_dim_step(struct dim *dim) +{ + if (dim->tune_state == DIM_GOING_RIGHT) { + if (dim->profile_ix == (RDMA_DIM_PARAMS_NUM_PROFILES - 1)) + return DIM_ON_EDGE; + dim->profile_ix++; + dim->steps_right++; + } + if (dim->tune_state == DIM_GOING_LEFT) { + if (dim->profile_ix == 0) + return DIM_ON_EDGE; + dim->profile_ix--; + dim->steps_left++; + } + + return DIM_STEPPED; +} + +static int rdma_dim_stats_compare(struct dim_stats *curr, + struct dim_stats *prev) +{ + /* first stat */ + if (!prev->cpms) + return DIM_STATS_SAME; + + if (IS_SIGNIFICANT_DIFF(curr->cpms, prev->cpms)) + return (curr->cpms > prev->cpms) ? DIM_STATS_BETTER : + DIM_STATS_WORSE; + + if (IS_SIGNIFICANT_DIFF(curr->cpe_ratio, prev->cpe_ratio)) + return (curr->cpe_ratio > prev->cpe_ratio) ? DIM_STATS_BETTER : + DIM_STATS_WORSE; + + return DIM_STATS_SAME; +} + +static bool rdma_dim_decision(struct dim_stats *curr_stats, struct dim *dim) +{ + int prev_ix = dim->profile_ix; + u8 state = dim->tune_state; + int stats_res; + int step_res; + + if (state != DIM_PARKING_ON_TOP && state != DIM_PARKING_TIRED) { + stats_res = rdma_dim_stats_compare(curr_stats, + &dim->prev_stats); + + switch (stats_res) { + case DIM_STATS_SAME: + if (curr_stats->cpe_ratio <= 50 * prev_ix) + dim->profile_ix = 0; + break; + case DIM_STATS_WORSE: + dim_turn(dim); + /* fall through */ + case DIM_STATS_BETTER: + step_res = rdma_dim_step(dim); + if (step_res == DIM_ON_EDGE) + dim_turn(dim); + break; + } + } + + dim->prev_stats = *curr_stats; + + return dim->profile_ix != prev_ix; +} + +void rdma_dim(struct dim *dim, u64 completions) +{ + struct dim_sample *curr_sample = &dim->measuring_sample; + struct dim_stats curr_stats; + u32 nevents; + + dim_update_sample_with_comps(curr_sample->event_ctr + 1, 0, 0, + curr_sample->comp_ctr + completions, + &dim->measuring_sample); + + switch (dim->state) { + case DIM_MEASURE_IN_PROGRESS: + nevents = curr_sample->event_ctr - dim->start_sample.event_ctr; + if (nevents < DIM_NEVENTS) + break; + dim_calc_stats(&dim->start_sample, curr_sample, &curr_stats); + if (rdma_dim_decision(&curr_stats, dim)) { + dim->state = DIM_APPLY_NEW_PROFILE; + schedule_work(&dim->work); + break; + } + /* fall through */ + case DIM_START_MEASURE: + dim->state = DIM_MEASURE_IN_PROGRESS; + dim_update_sample_with_comps(curr_sample->event_ctr, 0, 0, + curr_sample->comp_ctr, + &dim->start_sample); + break; + case DIM_APPLY_NEW_PROFILE: + break; + } +} +EXPORT_SYMBOL(rdma_dim); |