Line data    Source code

       1             : /*   SPDX-License-Identifier: BSD-3-Clause
       2             :  *   Copyright (C) 2021 Intel Corporation.
       3             :  *   All rights reserved.
       4             :  */
       5             : 
       6             : #include "spdk/stdinc.h"
       7             : #include "spdk/likely.h"
       8             : 
       9             : #include "spdk_internal/event.h"
      10             : #include "spdk/thread.h"
      11             : 
      12             : #include "spdk/log.h"
      13             : #include "spdk/env.h"
      14             : #include "spdk/scheduler.h"
      15             : 
      16             : static uint32_t g_max_threshold = 99;
      17             : static uint32_t g_adjust_threshold = 50;
      18             : static uint32_t g_min_threshold = 1;
      19             : 
      20             : static int
      21           0 : init(void)
      22             : {
      23           0 :         return spdk_governor_set("dpdk_governor");
      24             : }
      25             : 
      26             : static void
      27           0 : deinit(void)
      28             : {
      29           0 :         spdk_governor_set(NULL);
      30           0 : }
      31             : 
      32             : static uint32_t
      33           0 : calculate_busy_pct(struct spdk_scheduler_core_info *core)
      34             : {
      35           0 :         uint64_t total_tsc;
      36             : 
      37           0 :         total_tsc = core->current_busy_tsc + core->current_idle_tsc;
      38           0 :         if (total_tsc == 0) {
      39           0 :                 return 0;
      40             :         } else {
      41           0 :                 return core->current_busy_tsc * 100 / total_tsc;
      42             :         }
      43           0 : }
      44             : 
      45             : struct check_sibling_ctx {
      46             :         struct spdk_scheduler_core_info *cores;
      47             :         uint32_t busy_pct;
      48             : };
      49             : 
      50             : static void
      51           0 : check_sibling(void *_ctx, uint32_t i)
      52             : {
      53           0 :         struct check_sibling_ctx *ctx = _ctx;
      54           0 :         struct spdk_scheduler_core_info *core = &ctx->cores[i];
      55           0 :         uint32_t busy_pct = calculate_busy_pct(core);
      56             : 
      57           0 :         ctx->busy_pct = spdk_max(ctx->busy_pct, busy_pct);
      58           0 : }
      59             : 
      60             : static void
      61           0 : balance(struct spdk_scheduler_core_info *cores, uint32_t core_count)
      62             : {
      63           0 :         struct spdk_governor *governor;
      64           0 :         struct spdk_scheduler_core_info *core;
      65           0 :         struct spdk_governor_capabilities capabilities;
      66           0 :         uint32_t busy_pct;
      67           0 :         uint32_t i;
      68           0 :         int rc;
      69             : 
      70           0 :         governor = spdk_governor_get();
      71           0 :         assert(governor != NULL);
      72             : 
      73             :         /* Gather active/idle statistics */
      74           0 :         SPDK_ENV_FOREACH_CORE(i) {
      75           0 :                 struct spdk_cpuset smt_siblings = {};
      76           0 :                 core = &cores[i];
      77             : 
      78           0 :                 rc = governor->get_core_capabilities(core->lcore, &capabilities);
      79           0 :                 if (rc < 0) {
      80           0 :                         SPDK_ERRLOG("failed to get capabilities for core: %u\n", core->lcore);
      81           0 :                         return;
      82             :                 }
      83             : 
      84           0 :                 busy_pct = calculate_busy_pct(core);
      85           0 :                 if (spdk_env_core_get_smt_cpuset(&smt_siblings, i)) {
      86           0 :                         struct check_sibling_ctx ctx = {.cores = cores, .busy_pct = busy_pct};
      87             : 
      88           0 :                         spdk_cpuset_for_each_cpu(&smt_siblings, check_sibling, &ctx);
      89           0 :                         busy_pct = ctx.busy_pct;
      90           0 :                 }
      91             : 
      92           0 :                 if (busy_pct < g_min_threshold) {
      93           0 :                         rc = governor->set_core_freq_min(core->lcore);
      94           0 :                         if (rc < 0) {
      95           0 :                                 SPDK_ERRLOG("setting to minimal frequency for core %u failed\n", core->lcore);
      96           0 :                         }
      97           0 :                 } else if (busy_pct < g_adjust_threshold) {
      98           0 :                         rc = governor->core_freq_down(core->lcore);
      99           0 :                         if (rc < 0) {
     100           0 :                                 SPDK_ERRLOG("lowering frequency for core %u failed\n", core->lcore);
     101           0 :                         }
     102           0 :                 } else if (busy_pct >= g_max_threshold) {
     103           0 :                         rc = governor->set_core_freq_max(core->lcore);
     104           0 :                         if (rc < 0) {
     105           0 :                                 SPDK_ERRLOG("setting to maximal frequency for core %u failed\n", core->lcore);
     106           0 :                         }
     107           0 :                 } else {
     108           0 :                         rc = governor->core_freq_up(core->lcore);
     109           0 :                         if (rc < 0) {
     110           0 :                                 SPDK_ERRLOG("increasing frequency for core %u failed\n", core->lcore);
     111           0 :                         }
     112             :                 }
     113           0 :         }
     114           0 : }
     115             : 
     116             : static struct spdk_scheduler gscheduler = {
     117             :         .name = "gscheduler",
     118             :         .init = init,
     119             :         .deinit = deinit,
     120             :         .balance = balance,
     121             : };
     122             : 
     123           0 : SPDK_SCHEDULER_REGISTER(gscheduler);