diff options
Diffstat (limited to 'drivers/infiniband/hw/bnxt_re/main.c')
| -rw-r--r-- | drivers/infiniband/hw/bnxt_re/main.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/bnxt_re/main.c b/drivers/infiniband/hw/bnxt_re/main.c index 13cd84d68e1f..6469811003f6 100644 --- a/drivers/infiniband/hw/bnxt_re/main.c +++ b/drivers/infiniband/hw/bnxt_re/main.c @@ -475,6 +475,125 @@ static void bnxt_re_set_default_pacing_data(struct bnxt_re_dev *rdev) pacing_data->pacing_th * BNXT_RE_PACING_ALARM_TH_MULTIPLE; } +static void __wait_for_fifo_occupancy_below_th(struct bnxt_re_dev *rdev) +{ + u32 read_val, fifo_occup; + + /* loop shouldn't run infintely as the occupancy usually goes + * below pacing algo threshold as soon as pacing kicks in. + */ + while (1) { + read_val = readl(rdev->en_dev->bar0 + rdev->pacing.dbr_db_fifo_reg_off); + fifo_occup = BNXT_RE_MAX_FIFO_DEPTH - + ((read_val & BNXT_RE_DB_FIFO_ROOM_MASK) >> + BNXT_RE_DB_FIFO_ROOM_SHIFT); + /* Fifo occupancy cannot be greater the MAX FIFO depth */ + if (fifo_occup > BNXT_RE_MAX_FIFO_DEPTH) + break; + + if (fifo_occup < rdev->qplib_res.pacing_data->pacing_th) + break; + } +} + +static void bnxt_re_db_fifo_check(struct work_struct *work) +{ + struct bnxt_re_dev *rdev = container_of(work, struct bnxt_re_dev, + dbq_fifo_check_work); + struct bnxt_qplib_db_pacing_data *pacing_data; + u32 pacing_save; + + if (!mutex_trylock(&rdev->pacing.dbq_lock)) + return; + pacing_data = rdev->qplib_res.pacing_data; + pacing_save = rdev->pacing.do_pacing_save; + __wait_for_fifo_occupancy_below_th(rdev); + cancel_delayed_work_sync(&rdev->dbq_pacing_work); + if (pacing_save > rdev->pacing.dbr_def_do_pacing) { + /* Double the do_pacing value during the congestion */ + pacing_save = pacing_save << 1; + } else { + /* + * when a new congestion is detected increase the do_pacing + * by 8 times. And also increase the pacing_th by 4 times. The + * reason to increase pacing_th is to give more space for the + * queue to oscillate down without getting empty, but also more + * room for the queue to increase without causing another alarm. + */ + pacing_save = pacing_save << 3; + pacing_data->pacing_th = rdev->pacing.pacing_algo_th * 4; + } + + if (pacing_save > BNXT_RE_MAX_DBR_DO_PACING) + pacing_save = BNXT_RE_MAX_DBR_DO_PACING; + + pacing_data->do_pacing = pacing_save; + rdev->pacing.do_pacing_save = pacing_data->do_pacing; + pacing_data->alarm_th = + pacing_data->pacing_th * BNXT_RE_PACING_ALARM_TH_MULTIPLE; + schedule_delayed_work(&rdev->dbq_pacing_work, + msecs_to_jiffies(rdev->pacing.dbq_pacing_time)); + mutex_unlock(&rdev->pacing.dbq_lock); +} + +static void bnxt_re_pacing_timer_exp(struct work_struct *work) +{ + struct bnxt_re_dev *rdev = container_of(work, struct bnxt_re_dev, + dbq_pacing_work.work); + struct bnxt_qplib_db_pacing_data *pacing_data; + u32 read_val, fifo_occup; + + if (!mutex_trylock(&rdev->pacing.dbq_lock)) + return; + + pacing_data = rdev->qplib_res.pacing_data; + read_val = readl(rdev->en_dev->bar0 + rdev->pacing.dbr_db_fifo_reg_off); + fifo_occup = BNXT_RE_MAX_FIFO_DEPTH - + ((read_val & BNXT_RE_DB_FIFO_ROOM_MASK) >> + BNXT_RE_DB_FIFO_ROOM_SHIFT); + + if (fifo_occup > pacing_data->pacing_th) + goto restart_timer; + + /* + * Instead of immediately going back to the default do_pacing + * reduce it by 1/8 times and restart the timer. + */ + pacing_data->do_pacing = pacing_data->do_pacing - (pacing_data->do_pacing >> 3); + pacing_data->do_pacing = max_t(u32, rdev->pacing.dbr_def_do_pacing, pacing_data->do_pacing); + if (pacing_data->do_pacing <= rdev->pacing.dbr_def_do_pacing) { + bnxt_re_set_default_pacing_data(rdev); + goto dbq_unlock; + } + +restart_timer: + schedule_delayed_work(&rdev->dbq_pacing_work, + msecs_to_jiffies(rdev->pacing.dbq_pacing_time)); +dbq_unlock: + rdev->pacing.do_pacing_save = pacing_data->do_pacing; + mutex_unlock(&rdev->pacing.dbq_lock); +} + +void bnxt_re_pacing_alert(struct bnxt_re_dev *rdev) +{ + struct bnxt_qplib_db_pacing_data *pacing_data; + + if (!rdev->pacing.dbr_pacing) + return; + mutex_lock(&rdev->pacing.dbq_lock); + pacing_data = rdev->qplib_res.pacing_data; + + /* + * Increase the alarm_th to max so that other user lib instances do not + * keep alerting the driver. + */ + pacing_data->alarm_th = BNXT_RE_MAX_FIFO_DEPTH; + pacing_data->do_pacing = BNXT_RE_MAX_DBR_DO_PACING; + cancel_work_sync(&rdev->dbq_fifo_check_work); + schedule_work(&rdev->dbq_fifo_check_work); + mutex_unlock(&rdev->pacing.dbq_lock); +} + static int bnxt_re_initialize_dbr_pacing(struct bnxt_re_dev *rdev) { if (bnxt_re_hwrm_dbr_pacing_qcfg(rdev)) @@ -506,11 +625,16 @@ static int bnxt_re_initialize_dbr_pacing(struct bnxt_re_dev *rdev) rdev->qplib_res.pacing_data->fifo_room_shift = BNXT_RE_DB_FIFO_ROOM_SHIFT; rdev->qplib_res.pacing_data->grc_reg_offset = rdev->pacing.dbr_db_fifo_reg_off; bnxt_re_set_default_pacing_data(rdev); + /* Initialize worker for DBR Pacing */ + INIT_WORK(&rdev->dbq_fifo_check_work, bnxt_re_db_fifo_check); + INIT_DELAYED_WORK(&rdev->dbq_pacing_work, bnxt_re_pacing_timer_exp); return 0; } static void bnxt_re_deinitialize_dbr_pacing(struct bnxt_re_dev *rdev) { + cancel_work_sync(&rdev->dbq_fifo_check_work); + cancel_delayed_work_sync(&rdev->dbq_pacing_work); if (rdev->pacing.dbr_page) free_page((u64)rdev->pacing.dbr_page); |