From 716ca530e1c4515d8683c9d5be3d56b301758b66 Mon Sep 17 00:00:00 2001 From: James <> Date: Wed, 4 Nov 2015 11:49:21 +0000 Subject: trunk-47381 --- ...-interrupts-disabled-as-long-as-there-is-.patch | 87 ++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch (limited to 'target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch') diff --git a/target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch b/target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch new file mode 100644 index 0000000..3bbe9ea --- /dev/null +++ b/target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch @@ -0,0 +1,87 @@ +From: Felix Fietkau +Date: Sun, 12 Apr 2015 10:08:04 +0200 +Subject: [PATCH] bgmac: leave interrupts disabled as long as there is work + to do + +Always poll rx and tx during NAPI poll instead of relying on the status +of the first interrupt. This prevents bgmac_poll from leaving unfinished +work around until the next IRQ. +In my tests this makes bridging/routing throughput under heavy load more +stable and ensures that no new IRQs arrive as long as bgmac_poll uses up +the entire budget. + +Signed-off-by: Felix Fietkau +--- + +--- a/drivers/net/ethernet/broadcom/bgmac.c ++++ b/drivers/net/ethernet/broadcom/bgmac.c +@@ -1109,8 +1109,6 @@ static void bgmac_chip_reset(struct bgma + bgmac_phy_init(bgmac); + + netdev_reset_queue(bgmac->net_dev); +- +- bgmac->int_status = 0; + } + + static void bgmac_chip_intrs_on(struct bgmac *bgmac) +@@ -1225,14 +1223,13 @@ static irqreturn_t bgmac_interrupt(int i + if (!int_status) + return IRQ_NONE; + +- /* Ack */ +- bgmac_write(bgmac, BGMAC_INT_STATUS, int_status); ++ int_status &= ~(BGMAC_IS_TX0 | BGMAC_IS_RX); ++ if (int_status) ++ bgmac_err(bgmac, "Unknown IRQs: 0x%08X\n", int_status); + + /* Disable new interrupts until handling existing ones */ + bgmac_chip_intrs_off(bgmac); + +- bgmac->int_status = int_status; +- + napi_schedule(&bgmac->napi); + + return IRQ_HANDLED; +@@ -1241,25 +1238,17 @@ static irqreturn_t bgmac_interrupt(int i + static int bgmac_poll(struct napi_struct *napi, int weight) + { + struct bgmac *bgmac = container_of(napi, struct bgmac, napi); +- struct bgmac_dma_ring *ring; + int handled = 0; + +- if (bgmac->int_status & BGMAC_IS_TX0) { +- ring = &bgmac->tx_ring[0]; +- bgmac_dma_tx_free(bgmac, ring); +- bgmac->int_status &= ~BGMAC_IS_TX0; +- } ++ /* Ack */ ++ bgmac_write(bgmac, BGMAC_INT_STATUS, ~0); + +- if (bgmac->int_status & BGMAC_IS_RX) { +- ring = &bgmac->rx_ring[0]; +- handled += bgmac_dma_rx_read(bgmac, ring, weight); +- bgmac->int_status &= ~BGMAC_IS_RX; +- } ++ bgmac_dma_tx_free(bgmac, &bgmac->tx_ring[0]); ++ handled += bgmac_dma_rx_read(bgmac, &bgmac->rx_ring[0], weight); + +- if (bgmac->int_status) { +- bgmac_err(bgmac, "Unknown IRQs: 0x%08X\n", bgmac->int_status); +- bgmac->int_status = 0; +- } ++ /* Poll again if more events arrived in the meantime */ ++ if (bgmac_read(bgmac, BGMAC_INT_STATUS) & (BGMAC_IS_TX0 | BGMAC_IS_RX)) ++ return handled; + + if (handled < weight) { + napi_complete(napi); +--- a/drivers/net/ethernet/broadcom/bgmac.h ++++ b/drivers/net/ethernet/broadcom/bgmac.h +@@ -452,7 +452,6 @@ struct bgmac { + + /* Int */ + u32 int_mask; +- u32 int_status; + + /* Current MAC state */ + int mac_speed; -- cgit v1.2.3