88 lines · c
1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB2/*3 * Copyright (c) 2019, Mellanox Technologies inc. All rights reserved.4 */5 6#include <linux/dim.h>7 8bool 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}20EXPORT_SYMBOL(dim_on_top);21 22void 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}38EXPORT_SYMBOL(dim_turn);39 40void 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}47EXPORT_SYMBOL(dim_park_on_top);48 49void 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}55EXPORT_SYMBOL(dim_park_tired);56 57bool dim_calc_stats(struct dim_sample *start, struct dim_sample *end,58 struct dim_stats *curr_stats)59{60 /* u32 holds up to 71 minutes, should be enough */61 u32 delta_us = ktime_us_delta(end->time, start->time);62 u32 npkts = BIT_GAP(BITS_PER_TYPE(u32), end->pkt_ctr, start->pkt_ctr);63 u32 nbytes = BIT_GAP(BITS_PER_TYPE(u32), end->byte_ctr,64 start->byte_ctr);65 u32 ncomps = BIT_GAP(BITS_PER_TYPE(u32), end->comp_ctr,66 start->comp_ctr);67 68 if (!delta_us)69 return false;70 71 curr_stats->ppms = DIV_ROUND_UP(npkts * USEC_PER_MSEC, delta_us);72 curr_stats->bpms = DIV_ROUND_UP(nbytes * USEC_PER_MSEC, delta_us);73 curr_stats->epms = DIV_ROUND_UP(DIM_NEVENTS * USEC_PER_MSEC,74 delta_us);75 curr_stats->cpms = DIV_ROUND_UP(ncomps * USEC_PER_MSEC, delta_us);76 if (curr_stats->epms != 0)77 curr_stats->cpe_ratio = DIV_ROUND_DOWN_ULL(78 curr_stats->cpms * 100, curr_stats->epms);79 else80 curr_stats->cpe_ratio = 0;81 82 return true;83}84EXPORT_SYMBOL(dim_calc_stats);85 86MODULE_DESCRIPTION("Dynamic Interrupt Moderation (DIM) library");87MODULE_LICENSE("Dual BSD/GPL");88