1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB 2 /* 3 * Copyright (c) 2019, Mellanox Technologies inc. All rights reserved. 4 */ 5 6 #include <linux/dim.h> 7 8 bool dim_on_top(struct dim *dim) 9 { 10 switch (dim->tune_state) { 11 case DIM_PARKING_ON_TOP: 12 case DIM_PARKING_TIRED: 13 return true; 14 case DIM_GOING_RIGHT: 15 return (dim->steps_left > 1) && (dim->steps_right == 1); 16 default: /* DIM_GOING_LEFT */ 17 return (dim->steps_right > 1) && (dim->steps_left == 1); 18 } 19 } 20 EXPORT_SYMBOL(dim_on_top); 21 22 void dim_turn(struct dim *dim) 23 { 24 switch (dim->tune_state) { 25 case DIM_PARKING_ON_TOP: 26 case DIM_PARKING_TIRED: 27 break; 28 case DIM_GOING_RIGHT: 29 dim->tune_state = DIM_GOING_LEFT; 30 dim->steps_left = 0; 31 break; 32 case DIM_GOING_LEFT: 33 dim->tune_state = DIM_GOING_RIGHT; 34 dim->steps_right = 0; 35 break; 36 } 37 } 38 EXPORT_SYMBOL(dim_turn); 39 40 void dim_park_on_top(struct dim *dim) 41 { 42 dim->steps_right = 0; 43 dim->steps_left = 0; 44 dim->tired = 0; 45 dim->tune_state = DIM_PARKING_ON_TOP; 46 } 47 EXPORT_SYMBOL(dim_park_on_top); 48 49 void dim_park_tired(struct dim *dim) 50 { 51 dim->steps_right = 0; 52 dim->steps_left = 0; 53 dim->tune_state = DIM_PARKING_TIRED; 54 } 55 EXPORT_SYMBOL(dim_park_tired); 56 57 bool dim_calc_stats(const struct dim_sample *start, 58 const struct dim_sample *end, 59 struct dim_stats *curr_stats) 60 { 61 /* u32 holds up to 71 minutes, should be enough */ 62 u32 delta_us = ktime_us_delta(end->time, start->time); 63 u32 npkts = BIT_GAP(BITS_PER_TYPE(u32), end->pkt_ctr, start->pkt_ctr); 64 u32 nbytes = BIT_GAP(BITS_PER_TYPE(u32), end->byte_ctr, 65 start->byte_ctr); 66 u32 ncomps = BIT_GAP(BITS_PER_TYPE(u32), end->comp_ctr, 67 start->comp_ctr); 68 69 if (!delta_us) 70 return false; 71 72 curr_stats->ppms = DIV_ROUND_UP(npkts * USEC_PER_MSEC, delta_us); 73 curr_stats->bpms = DIV_ROUND_UP(nbytes * USEC_PER_MSEC, delta_us); 74 curr_stats->epms = DIV_ROUND_UP(DIM_NEVENTS * USEC_PER_MSEC, 75 delta_us); 76 curr_stats->cpms = DIV_ROUND_UP(ncomps * USEC_PER_MSEC, delta_us); 77 if (curr_stats->epms != 0) 78 curr_stats->cpe_ratio = DIV_ROUND_DOWN_ULL( 79 curr_stats->cpms * 100, curr_stats->epms); 80 else 81 curr_stats->cpe_ratio = 0; 82 83 return true; 84 } 85 EXPORT_SYMBOL(dim_calc_stats); 86 87 MODULE_DESCRIPTION("Dynamic Interrupt Moderation (DIM) library"); 88 MODULE_LICENSE("Dual BSD/GPL"); 89