Using MSI can avoid sharing IRQ and associated overhead. Tested on PCI-X. Signed-off-by: Stephen Hemminger --- drivers/net/chelsio/common.h | 1 + drivers/net/chelsio/cxgb2.c | 20 +++++++++++++++++--- 2 files changed, 18 insertions(+), 3 deletions(-) --- chelsio.orig/drivers/net/chelsio/common.h +++ chelsio/drivers/net/chelsio/common.h @@ -228,6 +228,7 @@ struct adapter_params { unsigned short chip_revision; unsigned char chip_version; unsigned char is_asic; + unsigned char has_msi; }; struct link_config { --- chelsio.orig/drivers/net/chelsio/cxgb2.c +++ chelsio/drivers/net/chelsio/cxgb2.c @@ -107,6 +107,10 @@ static int t1powersave = 1; /* HW defaul module_param(t1powersave, int, 0); MODULE_PARM_DESC(t1powersave, "Enable/Disable T1 powersaving mode"); +static int disable_msi = 0; +module_param(disable_msi, int, 0); +MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)"); + static const char pci_speed[][4] = { "33", "66", "100", "133" }; @@ -215,11 +219,19 @@ static int cxgb_up(struct adapter *adapt } t1_interrupts_clear(adapter); - if ((err = request_irq(adapter->pdev->irq, - t1_select_intr_handler(adapter), IRQF_SHARED, - adapter->name, adapter))) { + + adapter->params.has_msi = !disable_msi && pci_enable_msi(adapter->pdev) == 0; + err = request_irq(adapter->pdev->irq, + t1_select_intr_handler(adapter), + adapter->params.has_msi ? 0 : IRQF_SHARED, + adapter->name, adapter); + if (err) { + if (adapter->params.has_msi) + pci_disable_msi(adapter->pdev); + goto out_err; } + t1_sge_start(adapter->sge); t1_interrupts_enable(adapter); out_err: @@ -234,6 +246,8 @@ static void cxgb_down(struct adapter *ad t1_sge_stop(adapter->sge); t1_interrupts_disable(adapter); free_irq(adapter->pdev->irq, adapter); + if (adapter->params.has_msi) + pci_disable_msi(adapter->pdev); } static int cxgb_open(struct net_device *dev) -- - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html