From c19eafccb22e1b1ca52439a936908cfd6fd12ff1 Mon Sep 17 00:00:00 2001 From: Rasesh Mody Date: Thu, 11 Apr 2019 18:47:41 -0700 Subject: [PATCH] net/bnx2x: fix race for periodic flags The periodic callout function and the interrupt handler both modify the periodic flags. There is a possible race condition when an application is going through dev_stop()/dev_start() and an interrupt handler is invoked. We also need to ensure that periodic polling is not invoked in interrupt context. This patch handles such case by using separate variable to check for interrupt context. Also, atomically load and store the periodic flag value. Fixes: 0f6ebeee2402 ("net/bnx2x: fix call to link handling periodic function") Cc: stable@dpdk.org Signed-off-by: Rasesh Mody --- drivers/net/bnx2x/bnx2x_ethdev.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/net/bnx2x/bnx2x_ethdev.c b/drivers/net/bnx2x/bnx2x_ethdev.c index f85766c687..3063aea647 100644 --- a/drivers/net/bnx2x/bnx2x_ethdev.c +++ b/drivers/net/bnx2x/bnx2x_ethdev.c @@ -108,14 +108,15 @@ bnx2x_link_update(struct rte_eth_dev *dev) } static void -bnx2x_interrupt_action(struct rte_eth_dev *dev) +bnx2x_interrupt_action(struct rte_eth_dev *dev, int intr_cxt) { struct bnx2x_softc *sc = dev->data->dev_private; uint32_t link_status; bnx2x_intr_legacy(sc); - if (sc->periodic_flags & PERIODIC_GO) + if ((atomic_load_acq_long(&sc->periodic_flags) == PERIODIC_GO) && + !intr_cxt) bnx2x_periodic_callout(sc); link_status = REG_RD(sc, sc->link_params.shmem_base + offsetof(struct shmem_region, @@ -132,9 +133,7 @@ bnx2x_interrupt_handler(void *param) PMD_DEBUG_PERIODIC_LOG(INFO, sc, "Interrupt handled"); - atomic_store_rel_long(&sc->periodic_flags, PERIODIC_STOP); - bnx2x_interrupt_action(dev); - atomic_store_rel_long(&sc->periodic_flags, PERIODIC_GO); + bnx2x_interrupt_action(dev, 1); rte_intr_enable(&sc->pci_dev->intr_handle); } @@ -145,7 +144,7 @@ static void bnx2x_periodic_start(void *param) int ret = 0; atomic_store_rel_long(&sc->periodic_flags, PERIODIC_GO); - bnx2x_interrupt_action(dev); + bnx2x_interrupt_action(dev, 0); if (IS_PF(sc)) { ret = rte_eal_alarm_set(BNX2X_SP_TIMER_PERIOD, bnx2x_periodic_start, (void *)dev); @@ -165,6 +164,8 @@ void bnx2x_periodic_stop(void *param) atomic_store_rel_long(&sc->periodic_flags, PERIODIC_STOP); rte_eal_alarm_cancel(bnx2x_periodic_start, (void *)dev); + + PMD_DRV_LOG(DEBUG, sc, "Periodic poll stopped"); } /* @@ -226,8 +227,10 @@ bnx2x_dev_start(struct rte_eth_dev *dev) PMD_INIT_FUNC_TRACE(sc); /* start the periodic callout */ - if (sc->periodic_flags & PERIODIC_STOP) + if (atomic_load_acq_long(&sc->periodic_flags) == PERIODIC_STOP) { bnx2x_periodic_start(dev); + PMD_DRV_LOG(DEBUG, sc, "Periodic poll re-started"); + } ret = bnx2x_init(sc); if (ret) { -- 2.20.1