From 6be5ed3fef568ad79f9519db4a336c725a089d51 Mon Sep 17 00:00:00 2001 From: Claudiu Manoil Date: Tue, 19 Mar 2013 07:40:03 +0000 Subject: [PATCH] gianfar: Poll only active Rx queues Split the napi budget fairly among the active queues only, instead of dividing it by the total number of Rx queues assigned to the given interrupt group. Use the h/w indication field RXFi in rstat (receive status register) to identify the active rx queues from the current interrupt group (i.e. receive event occured on ring i, if ring i is part of the current interrupt group). This indication field in rstat, RXFi i=0..7, allows us to find out on which queues of the same interrupt group do we have incomming traffic once we entered the polling routine for the given interrupt group. After servicing the ring i, the corresponding bit RXFi will be written with 1 to clear the active queue indication for that ring. Signed-off-by: Claudiu Manoil Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/gianfar.c | 28 ++++++++++++++++-------- drivers/net/ethernet/freescale/gianfar.h | 4 +++- 2 files changed, 22 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c index 1e555a70b821..3f07dbd01980 100644 --- a/drivers/net/ethernet/freescale/gianfar.c +++ b/drivers/net/ethernet/freescale/gianfar.c @@ -2835,15 +2835,20 @@ static int gfar_poll(struct napi_struct *napi, int budget) int work_done = 0, work_done_per_q = 0; int i, budget_per_q; int has_tx_work; - unsigned long serviced_queues = 0; - int num_queues = gfargrp->num_rx_queues; + unsigned long rstat_rxf; + int num_act_queues; - budget_per_q = budget/num_queues; /* Clear IEVENT, so interrupts aren't called again * because of the packets that have already arrived */ gfar_write(®s->ievent, IEVENT_RTX_MASK); + rstat_rxf = gfar_read(®s->rstat) & RSTAT_RXF_MASK; + + num_act_queues = bitmap_weight(&rstat_rxf, MAX_RX_QS); + if (num_act_queues) + budget_per_q = budget/num_act_queues; + while (1) { has_tx_work = 0; for_each_set_bit(i, &gfargrp->tx_bit_map, priv->num_tx_queues) { @@ -2856,7 +2861,8 @@ static int gfar_poll(struct napi_struct *napi, int budget) } for_each_set_bit(i, &gfargrp->rx_bit_map, priv->num_rx_queues) { - if (test_bit(i, &serviced_queues)) + /* skip queue if not active */ + if (!(rstat_rxf & (RSTAT_CLEAR_RXF0 >> i))) continue; rx_queue = priv->rx_queue[i]; @@ -2866,20 +2872,24 @@ static int gfar_poll(struct napi_struct *napi, int budget) /* finished processing this queue */ if (work_done_per_q < budget_per_q) { - set_bit(i, &serviced_queues); - num_queues--; - if (!num_queues) + /* clear active queue hw indication */ + gfar_write(®s->rstat, + RSTAT_CLEAR_RXF0 >> i); + rstat_rxf &= ~(RSTAT_CLEAR_RXF0 >> i); + num_act_queues--; + + if (!num_act_queues) break; /* recompute budget per Rx queue */ budget_per_q = - (budget - work_done) / num_queues; + (budget - work_done) / num_act_queues; } } if (work_done >= budget) break; - if (!num_queues && !has_tx_work) { + if (!num_act_queues && !has_tx_work) { napi_complete(napi); diff --git a/drivers/net/ethernet/freescale/gianfar.h b/drivers/net/ethernet/freescale/gianfar.h index 63a28d294e20..b1d0c1c77139 100644 --- a/drivers/net/ethernet/freescale/gianfar.h +++ b/drivers/net/ethernet/freescale/gianfar.h @@ -291,7 +291,9 @@ extern const char gfar_driver_version[]; #define RCTRL_PADDING(x) ((x << 16) & RCTRL_PAL_MASK) -#define RSTAT_CLEAR_RHALT 0x00800000 +#define RSTAT_CLEAR_RHALT 0x00800000 +#define RSTAT_CLEAR_RXF0 0x00000080 +#define RSTAT_RXF_MASK 0x000000ff #define TCTRL_IPCSEN 0x00004000 #define TCTRL_TUCSEN 0x00002000 -- 2.20.1