| Message ID | a010f2cde3de80132d82acb2812b82343ea54c95.1480412215.git-series.gregory.clement@free-electrons.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
Hi Gregory, Apparently HWBM had a mistake in implementation, please see below. 2016-11-29 10:37 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: > Until now the virtual address of the received buffer were stored in the > cookie field of the rx descriptor. However, this field is 32-bits only > which prevents to use the driver on a 64-bits architecture. > > With this patch the virtual address is stored in an array not shared with > the hardware (no more need to use the DMA API). Thanks to this, it is > possible to use cache contrary to the access of the rx descriptor member. > > The change is done in the swbm path only because the hwbm uses the cookie > field, this also means that currently the hwbm is not usable in 64-bits. > > Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> > --- > drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- > 1 file changed, 81 insertions(+), 12 deletions(-) > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > index 1b84f746d748..32b142d0e44e 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -561,6 +561,9 @@ struct mvneta_rx_queue { > u32 pkts_coal; > u32 time_coal; > > + /* Virtual address of the RX buffer */ > + void **buf_virt_addr; > + > /* Virtual address of the RX DMA descriptors array */ > struct mvneta_rx_desc *descs; > > @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, > > /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ > static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, > - u32 phys_addr, u32 cookie) > + u32 phys_addr, void *virt_addr, > + struct mvneta_rx_queue *rxq) > { > - rx_desc->buf_cookie = cookie; > + int i; > + > rx_desc->buf_phys_addr = phys_addr; > + i = rx_desc - rxq->descs; > + rxq->buf_virt_addr[i] = virt_addr; > } > > /* Decrement sent descriptors counter */ > @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); > > /* Refill processing for SW buffer management */ > static int mvneta_rx_refill(struct mvneta_port *pp, > - struct mvneta_rx_desc *rx_desc) > + struct mvneta_rx_desc *rx_desc, > + struct mvneta_rx_queue *rxq) > > { > dma_addr_t phys_addr; > @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, > return -ENOMEM; > } > > - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); > + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); > return 0; > } > > @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, > > for (i = 0; i < rxq->size; i++) { > struct mvneta_rx_desc *rx_desc = rxq->descs + i; > - void *data = (void *)rx_desc->buf_cookie; > + void *data; > + > + if (!pp->bm_priv) > + data = rxq->buf_virt_addr[i]; > + else > + data = (void *)(uintptr_t)rx_desc->buf_cookie; > > dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr, > MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE); > @@ -1894,12 +1907,13 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, > unsigned char *data; > dma_addr_t phys_addr; > u32 rx_status, frag_size; > - int rx_bytes, err; > + int rx_bytes, err, index; > > rx_done++; > rx_status = rx_desc->status; > rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); > - data = (unsigned char *)rx_desc->buf_cookie; > + index = rx_desc - rxq->descs; > + data = (unsigned char *)rxq->buf_virt_addr[index]; > phys_addr = rx_desc->buf_phys_addr; > > if (!mvneta_rxq_desc_is_first_last(rx_status) || > @@ -1938,7 +1952,7 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, > } > > /* Refill processing */ > - err = mvneta_rx_refill(pp, rx_desc); > + err = mvneta_rx_refill(pp, rx_desc, rxq); > if (err) { > netdev_err(dev, "Linux processing - Can't refill\n"); > rxq->missed++; > @@ -2020,7 +2034,7 @@ static int mvneta_rx_hwbm(struct mvneta_port *pp, int rx_todo, > rx_done++; > rx_status = rx_desc->status; > rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); > - data = (unsigned char *)rx_desc->buf_cookie; > + data = (u8 *)(uintptr_t)rx_desc->buf_cookie; > phys_addr = rx_desc->buf_phys_addr; > pool_id = MVNETA_RX_GET_BM_POOL_ID(rx_desc); > bm_pool = &pp->bm_priv->bm_pools[pool_id]; > @@ -2708,6 +2722,56 @@ static int mvneta_poll(struct napi_struct *napi, int budget) > return rx_done; > } > > +/* Refill processing for HW buffer management */ > +static int mvneta_rx_hwbm_refill(struct mvneta_port *pp, > + struct mvneta_rx_desc *rx_desc) > + > +{ > + dma_addr_t phys_addr; > + void *data; > + > + data = mvneta_frag_alloc(pp->frag_size); > + if (!data) > + return -ENOMEM; > + > + phys_addr = dma_map_single(pp->dev->dev.parent, data, > + MVNETA_RX_BUF_SIZE(pp->pkt_size), > + DMA_FROM_DEVICE); > + if (unlikely(dma_mapping_error(pp->dev->dev.parent, phys_addr))) { > + mvneta_frag_free(pp->frag_size, data); > + return -ENOMEM; > + } > + > + rx_desc->buf_phys_addr = phys_addr; > + rx_desc->buf_cookie = (uintptr_t)data; > + > + return 0; > +} > + > +/* Handle rxq fill: allocates rxq skbs; called when initializing a port */ > +static int mvneta_rxq_bm_fill(struct mvneta_port *pp, > + struct mvneta_rx_queue *rxq, > + int num) > +{ > + int i; > + > + for (i = 0; i < num; i++) { > + memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); > + if (mvneta_rx_hwbm_refill(pp, rxq->descs + i) != 0) { > + netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", > + __func__, rxq->id, i, num); > + break; > + } > + } > + > + /* Add this number of RX descriptors as non occupied (ready to > + * get packets) > + */ > + mvneta_rxq_non_occup_desc_add(pp, rxq, i); > + > + return i; > +} > + > /* Handle rxq fill: allocates rxq skbs; called when initializing a port */ > static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, > int num) > @@ -2716,7 +2780,7 @@ static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, > > for (i = 0; i < num; i++) { > memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); > - if (mvneta_rx_refill(pp, rxq->descs + i) != 0) { > + if (mvneta_rx_refill(pp, rxq->descs + i, rxq) != 0) { > netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", > __func__, rxq->id, i, num); > break; > @@ -2784,14 +2848,14 @@ static int mvneta_rxq_init(struct mvneta_port *pp, > mvneta_rxq_buf_size_set(pp, rxq, > MVNETA_RX_BUF_SIZE(pp->pkt_size)); > mvneta_rxq_bm_disable(pp, rxq); > + mvneta_rxq_fill(pp, rxq, rxq->size); > } else { > mvneta_rxq_bm_enable(pp, rxq); > mvneta_rxq_long_pool_set(pp, rxq); > mvneta_rxq_short_pool_set(pp, rxq); > + mvneta_rxq_bm_fill(pp, rxq, rxq->size); Manual filling descriptors with new buffers is redundant. For HWBM, all buffers are allocated in mvneta_bm_construct() and in runtime they are put into descriptors by hardware. I think it's enough to add here: mvneta_rxq_non_occup_desc_add(pp, rxq, rxq->size); And remove mvneta_rxq_bm_fill and mvneta_rx_hwbm_refill. Best regards, Marcin
Hi Gregory, Another remark below, sorry for noise. 2016-11-29 10:37 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: > Until now the virtual address of the received buffer were stored in the > cookie field of the rx descriptor. However, this field is 32-bits only > which prevents to use the driver on a 64-bits architecture. > > With this patch the virtual address is stored in an array not shared with > the hardware (no more need to use the DMA API). Thanks to this, it is > possible to use cache contrary to the access of the rx descriptor member. > > The change is done in the swbm path only because the hwbm uses the cookie > field, this also means that currently the hwbm is not usable in 64-bits. > > Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> > --- > drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- > 1 file changed, 81 insertions(+), 12 deletions(-) > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > index 1b84f746d748..32b142d0e44e 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -561,6 +561,9 @@ struct mvneta_rx_queue { > u32 pkts_coal; > u32 time_coal; > > + /* Virtual address of the RX buffer */ > + void **buf_virt_addr; > + > /* Virtual address of the RX DMA descriptors array */ > struct mvneta_rx_desc *descs; > > @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, > > /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ > static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, > - u32 phys_addr, u32 cookie) > + u32 phys_addr, void *virt_addr, > + struct mvneta_rx_queue *rxq) > { > - rx_desc->buf_cookie = cookie; > + int i; > + > rx_desc->buf_phys_addr = phys_addr; > + i = rx_desc - rxq->descs; > + rxq->buf_virt_addr[i] = virt_addr; > } > > /* Decrement sent descriptors counter */ > @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); > > /* Refill processing for SW buffer management */ > static int mvneta_rx_refill(struct mvneta_port *pp, > - struct mvneta_rx_desc *rx_desc) > + struct mvneta_rx_desc *rx_desc, > + struct mvneta_rx_queue *rxq) > > { > dma_addr_t phys_addr; > @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, > return -ENOMEM; > } > > - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); > + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); > return 0; > } > > @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, > > for (i = 0; i < rxq->size; i++) { > struct mvneta_rx_desc *rx_desc = rxq->descs + i; > - void *data = (void *)rx_desc->buf_cookie; > + void *data; > + > + if (!pp->bm_priv) > + data = rxq->buf_virt_addr[i]; > + else > + data = (void *)(uintptr_t)rx_desc->buf_cookie; Dropping packets for HWBM (in fact returning dropped buffers to the pool) is done a couple of lines above. This point will never be reached with HWBM enabled (and it's also incorrect). Best regards, Marcin
Hi Marcin, On mar., nov. 29 2016, Marcin Wojtas <mw@semihalf.com> wrote: > Hi Gregory, > > Apparently HWBM had a mistake in implementation, please see below. > > 2016-11-29 10:37 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: >> Until now the virtual address of the received buffer were stored in the >> cookie field of the rx descriptor. However, this field is 32-bits only >> which prevents to use the driver on a 64-bits architecture. >> >> With this patch the virtual address is stored in an array not shared with >> the hardware (no more need to use the DMA API). Thanks to this, it is >> possible to use cache contrary to the access of the rx descriptor member. >> >> The change is done in the swbm path only because the hwbm uses the cookie >> field, this also means that currently the hwbm is not usable in 64-bits. >> >> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> >> --- >> drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- >> 1 file changed, 81 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c >> index 1b84f746d748..32b142d0e44e 100644 >> --- a/drivers/net/ethernet/marvell/mvneta.c >> +++ b/drivers/net/ethernet/marvell/mvneta.c >> @@ -561,6 +561,9 @@ struct mvneta_rx_queue { >> u32 pkts_coal; >> u32 time_coal; >> >> + /* Virtual address of the RX buffer */ >> + void **buf_virt_addr; >> + >> /* Virtual address of the RX DMA descriptors array */ >> struct mvneta_rx_desc *descs; >> >> @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, >> >> /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ >> static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, >> - u32 phys_addr, u32 cookie) >> + u32 phys_addr, void *virt_addr, >> + struct mvneta_rx_queue *rxq) >> { >> - rx_desc->buf_cookie = cookie; >> + int i; >> + >> rx_desc->buf_phys_addr = phys_addr; >> + i = rx_desc - rxq->descs; >> + rxq->buf_virt_addr[i] = virt_addr; >> } >> >> /* Decrement sent descriptors counter */ >> @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); >> >> /* Refill processing for SW buffer management */ >> static int mvneta_rx_refill(struct mvneta_port *pp, >> - struct mvneta_rx_desc *rx_desc) >> + struct mvneta_rx_desc *rx_desc, >> + struct mvneta_rx_queue *rxq) >> >> { >> dma_addr_t phys_addr; >> @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, >> return -ENOMEM; >> } >> >> - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); >> + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); >> return 0; >> } >> >> @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, >> >> for (i = 0; i < rxq->size; i++) { >> struct mvneta_rx_desc *rx_desc = rxq->descs + i; >> - void *data = (void *)rx_desc->buf_cookie; >> + void *data; >> + >> + if (!pp->bm_priv) >> + data = rxq->buf_virt_addr[i]; >> + else >> + data = (void *)(uintptr_t)rx_desc->buf_cookie; >> >> dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr, >> MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE); >> @@ -1894,12 +1907,13 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, >> unsigned char *data; >> dma_addr_t phys_addr; >> u32 rx_status, frag_size; >> - int rx_bytes, err; >> + int rx_bytes, err, index; >> >> rx_done++; >> rx_status = rx_desc->status; >> rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); >> - data = (unsigned char *)rx_desc->buf_cookie; >> + index = rx_desc - rxq->descs; >> + data = (unsigned char *)rxq->buf_virt_addr[index]; >> phys_addr = rx_desc->buf_phys_addr; >> >> if (!mvneta_rxq_desc_is_first_last(rx_status) || >> @@ -1938,7 +1952,7 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, >> } >> >> /* Refill processing */ >> - err = mvneta_rx_refill(pp, rx_desc); >> + err = mvneta_rx_refill(pp, rx_desc, rxq); >> if (err) { >> netdev_err(dev, "Linux processing - Can't refill\n"); >> rxq->missed++; >> @@ -2020,7 +2034,7 @@ static int mvneta_rx_hwbm(struct mvneta_port *pp, int rx_todo, >> rx_done++; >> rx_status = rx_desc->status; >> rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); >> - data = (unsigned char *)rx_desc->buf_cookie; >> + data = (u8 *)(uintptr_t)rx_desc->buf_cookie; >> phys_addr = rx_desc->buf_phys_addr; >> pool_id = MVNETA_RX_GET_BM_POOL_ID(rx_desc); >> bm_pool = &pp->bm_priv->bm_pools[pool_id]; >> @@ -2708,6 +2722,56 @@ static int mvneta_poll(struct napi_struct *napi, int budget) >> return rx_done; >> } >> >> +/* Refill processing for HW buffer management */ >> +static int mvneta_rx_hwbm_refill(struct mvneta_port *pp, >> + struct mvneta_rx_desc *rx_desc) >> + >> +{ >> + dma_addr_t phys_addr; >> + void *data; >> + >> + data = mvneta_frag_alloc(pp->frag_size); >> + if (!data) >> + return -ENOMEM; >> + >> + phys_addr = dma_map_single(pp->dev->dev.parent, data, >> + MVNETA_RX_BUF_SIZE(pp->pkt_size), >> + DMA_FROM_DEVICE); >> + if (unlikely(dma_mapping_error(pp->dev->dev.parent, phys_addr))) { >> + mvneta_frag_free(pp->frag_size, data); >> + return -ENOMEM; >> + } >> + >> + rx_desc->buf_phys_addr = phys_addr; >> + rx_desc->buf_cookie = (uintptr_t)data; >> + >> + return 0; >> +} >> + >> +/* Handle rxq fill: allocates rxq skbs; called when initializing a port */ >> +static int mvneta_rxq_bm_fill(struct mvneta_port *pp, >> + struct mvneta_rx_queue *rxq, >> + int num) >> +{ >> + int i; >> + >> + for (i = 0; i < num; i++) { >> + memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); >> + if (mvneta_rx_hwbm_refill(pp, rxq->descs + i) != 0) { >> + netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", >> + __func__, rxq->id, i, num); >> + break; >> + } >> + } >> + >> + /* Add this number of RX descriptors as non occupied (ready to >> + * get packets) >> + */ >> + mvneta_rxq_non_occup_desc_add(pp, rxq, i); >> + >> + return i; >> +} >> + >> /* Handle rxq fill: allocates rxq skbs; called when initializing a port */ >> static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, >> int num) >> @@ -2716,7 +2780,7 @@ static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, >> >> for (i = 0; i < num; i++) { >> memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); >> - if (mvneta_rx_refill(pp, rxq->descs + i) != 0) { >> + if (mvneta_rx_refill(pp, rxq->descs + i, rxq) != 0) { >> netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", >> __func__, rxq->id, i, num); >> break; >> @@ -2784,14 +2848,14 @@ static int mvneta_rxq_init(struct mvneta_port *pp, >> mvneta_rxq_buf_size_set(pp, rxq, >> MVNETA_RX_BUF_SIZE(pp->pkt_size)); >> mvneta_rxq_bm_disable(pp, rxq); >> + mvneta_rxq_fill(pp, rxq, rxq->size); >> } else { >> mvneta_rxq_bm_enable(pp, rxq); >> mvneta_rxq_long_pool_set(pp, rxq); >> mvneta_rxq_short_pool_set(pp, rxq); >> + mvneta_rxq_bm_fill(pp, rxq, rxq->size); > > Manual filling descriptors with new buffers is redundant. For HWBM, > all buffers are allocated in mvneta_bm_construct() and in runtime they > are put into descriptors by hardware. I think it's enough to add here: > mvneta_rxq_non_occup_desc_add(pp, rxq, rxq->size); > > And remove mvneta_rxq_bm_fill and mvneta_rx_hwbm_refill. You're right. I will do it it will simplify the code. Thanks, Gregory > > Best regards, > Marcin
Hi Marcin, On mar., nov. 29 2016, Marcin Wojtas <mw@semihalf.com> wrote: > Hi Gregory, > > Another remark below, sorry for noise. > > 2016-11-29 10:37 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: >> Until now the virtual address of the received buffer were stored in the >> cookie field of the rx descriptor. However, this field is 32-bits only >> which prevents to use the driver on a 64-bits architecture. >> >> With this patch the virtual address is stored in an array not shared with >> the hardware (no more need to use the DMA API). Thanks to this, it is >> possible to use cache contrary to the access of the rx descriptor member. >> >> The change is done in the swbm path only because the hwbm uses the cookie >> field, this also means that currently the hwbm is not usable in 64-bits. >> >> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> >> --- >> drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- >> 1 file changed, 81 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c >> index 1b84f746d748..32b142d0e44e 100644 >> --- a/drivers/net/ethernet/marvell/mvneta.c >> +++ b/drivers/net/ethernet/marvell/mvneta.c >> @@ -561,6 +561,9 @@ struct mvneta_rx_queue { >> u32 pkts_coal; >> u32 time_coal; >> >> + /* Virtual address of the RX buffer */ >> + void **buf_virt_addr; >> + >> /* Virtual address of the RX DMA descriptors array */ >> struct mvneta_rx_desc *descs; >> >> @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, >> >> /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ >> static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, >> - u32 phys_addr, u32 cookie) >> + u32 phys_addr, void *virt_addr, >> + struct mvneta_rx_queue *rxq) >> { >> - rx_desc->buf_cookie = cookie; >> + int i; >> + >> rx_desc->buf_phys_addr = phys_addr; >> + i = rx_desc - rxq->descs; >> + rxq->buf_virt_addr[i] = virt_addr; >> } >> >> /* Decrement sent descriptors counter */ >> @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); >> >> /* Refill processing for SW buffer management */ >> static int mvneta_rx_refill(struct mvneta_port *pp, >> - struct mvneta_rx_desc *rx_desc) >> + struct mvneta_rx_desc *rx_desc, >> + struct mvneta_rx_queue *rxq) >> >> { >> dma_addr_t phys_addr; >> @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, >> return -ENOMEM; >> } >> >> - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); >> + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); >> return 0; >> } >> >> @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, >> >> for (i = 0; i < rxq->size; i++) { >> struct mvneta_rx_desc *rx_desc = rxq->descs + i; >> - void *data = (void *)rx_desc->buf_cookie; >> + void *data; >> + >> + if (!pp->bm_priv) >> + data = rxq->buf_virt_addr[i]; >> + else >> + data = (void *)(uintptr_t)rx_desc->buf_cookie; > > Dropping packets for HWBM (in fact returning dropped buffers to the > pool) is done a couple of lines above. This point will never be indeed I changed the code at every place the buf_cookie was used and missed the fact that for HWBM this code was never reached. > reached with HWBM enabled (and it's also incorrect). What is incorrect? Gregory > > Best regards, > Marcin
Gregory, 2016-11-29 11:19 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: > Hi Marcin, > > On mar., nov. 29 2016, Marcin Wojtas <mw@semihalf.com> wrote: > >> Hi Gregory, >> >> Another remark below, sorry for noise. >> >> 2016-11-29 10:37 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: >>> Until now the virtual address of the received buffer were stored in the >>> cookie field of the rx descriptor. However, this field is 32-bits only >>> which prevents to use the driver on a 64-bits architecture. >>> >>> With this patch the virtual address is stored in an array not shared with >>> the hardware (no more need to use the DMA API). Thanks to this, it is >>> possible to use cache contrary to the access of the rx descriptor member. >>> >>> The change is done in the swbm path only because the hwbm uses the cookie >>> field, this also means that currently the hwbm is not usable in 64-bits. >>> >>> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> >>> --- >>> drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- >>> 1 file changed, 81 insertions(+), 12 deletions(-) >>> >>> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c >>> index 1b84f746d748..32b142d0e44e 100644 >>> --- a/drivers/net/ethernet/marvell/mvneta.c >>> +++ b/drivers/net/ethernet/marvell/mvneta.c >>> @@ -561,6 +561,9 @@ struct mvneta_rx_queue { >>> u32 pkts_coal; >>> u32 time_coal; >>> >>> + /* Virtual address of the RX buffer */ >>> + void **buf_virt_addr; >>> + >>> /* Virtual address of the RX DMA descriptors array */ >>> struct mvneta_rx_desc *descs; >>> >>> @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, >>> >>> /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ >>> static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, >>> - u32 phys_addr, u32 cookie) >>> + u32 phys_addr, void *virt_addr, >>> + struct mvneta_rx_queue *rxq) >>> { >>> - rx_desc->buf_cookie = cookie; >>> + int i; >>> + >>> rx_desc->buf_phys_addr = phys_addr; >>> + i = rx_desc - rxq->descs; >>> + rxq->buf_virt_addr[i] = virt_addr; >>> } >>> >>> /* Decrement sent descriptors counter */ >>> @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); >>> >>> /* Refill processing for SW buffer management */ >>> static int mvneta_rx_refill(struct mvneta_port *pp, >>> - struct mvneta_rx_desc *rx_desc) >>> + struct mvneta_rx_desc *rx_desc, >>> + struct mvneta_rx_queue *rxq) >>> >>> { >>> dma_addr_t phys_addr; >>> @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, >>> return -ENOMEM; >>> } >>> >>> - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); >>> + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); >>> return 0; >>> } >>> >>> @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, >>> >>> for (i = 0; i < rxq->size; i++) { >>> struct mvneta_rx_desc *rx_desc = rxq->descs + i; >>> - void *data = (void *)rx_desc->buf_cookie; >>> + void *data; >>> + >>> + if (!pp->bm_priv) >>> + data = rxq->buf_virt_addr[i]; >>> + else >>> + data = (void *)(uintptr_t)rx_desc->buf_cookie; >> >> Dropping packets for HWBM (in fact returning dropped buffers to the >> pool) is done a couple of lines above. This point will never be > > indeed I changed the code at every place the buf_cookie was used and > missed the fact that for HWBM this code was never reached. > >> reached with HWBM enabled (and it's also incorrect). > > What is incorrect? > Possible dma_unmapping + mvneta_frag_free for buffers in HWBM, when dropping packets. Thanks, Marcin
Hi Marcin, On mar., nov. 29 2016, Marcin Wojtas <mw@semihalf.com> wrote: > Gregory, > > 2016-11-29 11:19 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: >> Hi Marcin, >> >> On mar., nov. 29 2016, Marcin Wojtas <mw@semihalf.com> wrote: >> >>> Hi Gregory, >>> >>> Another remark below, sorry for noise. >>> >>> 2016-11-29 10:37 GMT+01:00 Gregory CLEMENT <gregory.clement@free-electrons.com>: >>>> Until now the virtual address of the received buffer were stored in the >>>> cookie field of the rx descriptor. However, this field is 32-bits only >>>> which prevents to use the driver on a 64-bits architecture. >>>> >>>> With this patch the virtual address is stored in an array not shared with >>>> the hardware (no more need to use the DMA API). Thanks to this, it is >>>> possible to use cache contrary to the access of the rx descriptor member. >>>> >>>> The change is done in the swbm path only because the hwbm uses the cookie >>>> field, this also means that currently the hwbm is not usable in 64-bits. >>>> >>>> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> >>>> --- >>>> drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- >>>> 1 file changed, 81 insertions(+), 12 deletions(-) >>>> >>>> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c >>>> index 1b84f746d748..32b142d0e44e 100644 >>>> --- a/drivers/net/ethernet/marvell/mvneta.c >>>> +++ b/drivers/net/ethernet/marvell/mvneta.c >>>> @@ -561,6 +561,9 @@ struct mvneta_rx_queue { >>>> u32 pkts_coal; >>>> u32 time_coal; >>>> >>>> + /* Virtual address of the RX buffer */ >>>> + void **buf_virt_addr; >>>> + >>>> /* Virtual address of the RX DMA descriptors array */ >>>> struct mvneta_rx_desc *descs; >>>> >>>> @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, >>>> >>>> /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ >>>> static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, >>>> - u32 phys_addr, u32 cookie) >>>> + u32 phys_addr, void *virt_addr, >>>> + struct mvneta_rx_queue *rxq) >>>> { >>>> - rx_desc->buf_cookie = cookie; >>>> + int i; >>>> + >>>> rx_desc->buf_phys_addr = phys_addr; >>>> + i = rx_desc - rxq->descs; >>>> + rxq->buf_virt_addr[i] = virt_addr; >>>> } >>>> >>>> /* Decrement sent descriptors counter */ >>>> @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); >>>> >>>> /* Refill processing for SW buffer management */ >>>> static int mvneta_rx_refill(struct mvneta_port *pp, >>>> - struct mvneta_rx_desc *rx_desc) >>>> + struct mvneta_rx_desc *rx_desc, >>>> + struct mvneta_rx_queue *rxq) >>>> >>>> { >>>> dma_addr_t phys_addr; >>>> @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, >>>> return -ENOMEM; >>>> } >>>> >>>> - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); >>>> + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); >>>> return 0; >>>> } >>>> >>>> @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, >>>> >>>> for (i = 0; i < rxq->size; i++) { >>>> struct mvneta_rx_desc *rx_desc = rxq->descs + i; >>>> - void *data = (void *)rx_desc->buf_cookie; >>>> + void *data; >>>> + >>>> + if (!pp->bm_priv) >>>> + data = rxq->buf_virt_addr[i]; >>>> + else >>>> + data = (void *)(uintptr_t)rx_desc->buf_cookie; >>> >>> Dropping packets for HWBM (in fact returning dropped buffers to the >>> pool) is done a couple of lines above. This point will never be >> >> indeed I changed the code at every place the buf_cookie was used and >> missed the fact that for HWBM this code was never reached. >> >>> reached with HWBM enabled (and it's also incorrect). >> >> What is incorrect? >> > > Possible dma_unmapping + mvneta_frag_free for buffers in HWBM, when > dropping packets. Yes sure, but as you mentioned this code is never reached when HWBM is enabled. I thought there was other part of the code to fix. Thanks, Gregory > > Thanks, > Marcin
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 1b84f746d748..32b142d0e44e 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -561,6 +561,9 @@ struct mvneta_rx_queue { u32 pkts_coal; u32 time_coal; + /* Virtual address of the RX buffer */ + void **buf_virt_addr; + /* Virtual address of the RX DMA descriptors array */ struct mvneta_rx_desc *descs; @@ -1573,10 +1576,14 @@ static void mvneta_tx_done_pkts_coal_set(struct mvneta_port *pp, /* Handle rx descriptor fill by setting buf_cookie and buf_phys_addr */ static void mvneta_rx_desc_fill(struct mvneta_rx_desc *rx_desc, - u32 phys_addr, u32 cookie) + u32 phys_addr, void *virt_addr, + struct mvneta_rx_queue *rxq) { - rx_desc->buf_cookie = cookie; + int i; + rx_desc->buf_phys_addr = phys_addr; + i = rx_desc - rxq->descs; + rxq->buf_virt_addr[i] = virt_addr; } /* Decrement sent descriptors counter */ @@ -1781,7 +1788,8 @@ EXPORT_SYMBOL_GPL(mvneta_frag_free); /* Refill processing for SW buffer management */ static int mvneta_rx_refill(struct mvneta_port *pp, - struct mvneta_rx_desc *rx_desc) + struct mvneta_rx_desc *rx_desc, + struct mvneta_rx_queue *rxq) { dma_addr_t phys_addr; @@ -1799,7 +1807,7 @@ static int mvneta_rx_refill(struct mvneta_port *pp, return -ENOMEM; } - mvneta_rx_desc_fill(rx_desc, phys_addr, (u32)data); + mvneta_rx_desc_fill(rx_desc, phys_addr, data, rxq); return 0; } @@ -1861,7 +1869,12 @@ static void mvneta_rxq_drop_pkts(struct mvneta_port *pp, for (i = 0; i < rxq->size; i++) { struct mvneta_rx_desc *rx_desc = rxq->descs + i; - void *data = (void *)rx_desc->buf_cookie; + void *data; + + if (!pp->bm_priv) + data = rxq->buf_virt_addr[i]; + else + data = (void *)(uintptr_t)rx_desc->buf_cookie; dma_unmap_single(pp->dev->dev.parent, rx_desc->buf_phys_addr, MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE); @@ -1894,12 +1907,13 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, unsigned char *data; dma_addr_t phys_addr; u32 rx_status, frag_size; - int rx_bytes, err; + int rx_bytes, err, index; rx_done++; rx_status = rx_desc->status; rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); - data = (unsigned char *)rx_desc->buf_cookie; + index = rx_desc - rxq->descs; + data = (unsigned char *)rxq->buf_virt_addr[index]; phys_addr = rx_desc->buf_phys_addr; if (!mvneta_rxq_desc_is_first_last(rx_status) || @@ -1938,7 +1952,7 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int rx_todo, } /* Refill processing */ - err = mvneta_rx_refill(pp, rx_desc); + err = mvneta_rx_refill(pp, rx_desc, rxq); if (err) { netdev_err(dev, "Linux processing - Can't refill\n"); rxq->missed++; @@ -2020,7 +2034,7 @@ static int mvneta_rx_hwbm(struct mvneta_port *pp, int rx_todo, rx_done++; rx_status = rx_desc->status; rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE); - data = (unsigned char *)rx_desc->buf_cookie; + data = (u8 *)(uintptr_t)rx_desc->buf_cookie; phys_addr = rx_desc->buf_phys_addr; pool_id = MVNETA_RX_GET_BM_POOL_ID(rx_desc); bm_pool = &pp->bm_priv->bm_pools[pool_id]; @@ -2708,6 +2722,56 @@ static int mvneta_poll(struct napi_struct *napi, int budget) return rx_done; } +/* Refill processing for HW buffer management */ +static int mvneta_rx_hwbm_refill(struct mvneta_port *pp, + struct mvneta_rx_desc *rx_desc) + +{ + dma_addr_t phys_addr; + void *data; + + data = mvneta_frag_alloc(pp->frag_size); + if (!data) + return -ENOMEM; + + phys_addr = dma_map_single(pp->dev->dev.parent, data, + MVNETA_RX_BUF_SIZE(pp->pkt_size), + DMA_FROM_DEVICE); + if (unlikely(dma_mapping_error(pp->dev->dev.parent, phys_addr))) { + mvneta_frag_free(pp->frag_size, data); + return -ENOMEM; + } + + rx_desc->buf_phys_addr = phys_addr; + rx_desc->buf_cookie = (uintptr_t)data; + + return 0; +} + +/* Handle rxq fill: allocates rxq skbs; called when initializing a port */ +static int mvneta_rxq_bm_fill(struct mvneta_port *pp, + struct mvneta_rx_queue *rxq, + int num) +{ + int i; + + for (i = 0; i < num; i++) { + memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); + if (mvneta_rx_hwbm_refill(pp, rxq->descs + i) != 0) { + netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", + __func__, rxq->id, i, num); + break; + } + } + + /* Add this number of RX descriptors as non occupied (ready to + * get packets) + */ + mvneta_rxq_non_occup_desc_add(pp, rxq, i); + + return i; +} + /* Handle rxq fill: allocates rxq skbs; called when initializing a port */ static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, int num) @@ -2716,7 +2780,7 @@ static int mvneta_rxq_fill(struct mvneta_port *pp, struct mvneta_rx_queue *rxq, for (i = 0; i < num; i++) { memset(rxq->descs + i, 0, sizeof(struct mvneta_rx_desc)); - if (mvneta_rx_refill(pp, rxq->descs + i) != 0) { + if (mvneta_rx_refill(pp, rxq->descs + i, rxq) != 0) { netdev_err(pp->dev, "%s:rxq %d, %d of %d buffs filled\n", __func__, rxq->id, i, num); break; @@ -2784,14 +2848,14 @@ static int mvneta_rxq_init(struct mvneta_port *pp, mvneta_rxq_buf_size_set(pp, rxq, MVNETA_RX_BUF_SIZE(pp->pkt_size)); mvneta_rxq_bm_disable(pp, rxq); + mvneta_rxq_fill(pp, rxq, rxq->size); } else { mvneta_rxq_bm_enable(pp, rxq); mvneta_rxq_long_pool_set(pp, rxq); mvneta_rxq_short_pool_set(pp, rxq); + mvneta_rxq_bm_fill(pp, rxq, rxq->size); } - mvneta_rxq_fill(pp, rxq, rxq->size); - return 0; } @@ -3865,6 +3929,11 @@ static int mvneta_init(struct device *dev, struct mvneta_port *pp) rxq->size = pp->rx_ring_size; rxq->pkts_coal = MVNETA_RX_COAL_PKTS; rxq->time_coal = MVNETA_RX_COAL_USEC; + rxq->buf_virt_addr = devm_kmalloc(pp->dev->dev.parent, + rxq->size * sizeof(void *), + GFP_KERNEL); + if (!rxq->buf_virt_addr) + return -ENOMEM; } return 0;
Until now the virtual address of the received buffer were stored in the cookie field of the rx descriptor. However, this field is 32-bits only which prevents to use the driver on a 64-bits architecture. With this patch the virtual address is stored in an array not shared with the hardware (no more need to use the DMA API). Thanks to this, it is possible to use cache contrary to the access of the rx descriptor member. The change is done in the swbm path only because the hwbm uses the cookie field, this also means that currently the hwbm is not usable in 64-bits. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> --- drivers/net/ethernet/marvell/mvneta.c | 93 ++++++++++++++++++++++++---- 1 file changed, 81 insertions(+), 12 deletions(-)