[PATCH RFC 14/77] bnx2x: Update MSI/MSI-X interrupts enablement code

From: Alexander Gordeev
Date: Wed Oct 02 2013 - 13:29:54 EST


As result of recent re-design of the MSI/MSI-X interrupts enabling
pattern this driver has to be updated to use the new technique to
obtain a optimal number of MSI/MSI-X interrupts required.

Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 54 ++++++++++-------------
1 files changed, 23 insertions(+), 31 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index 61726af..edf31d2 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -1564,7 +1564,7 @@ void bnx2x_free_irq(struct bnx2x *bp)

int bnx2x_enable_msix(struct bnx2x *bp)
{
- int msix_vec = 0, i, rc;
+ int msix_vec = 0, nvec, i, rc;

/* VFs don't have a default status block */
if (IS_PF(bp)) {
@@ -1590,60 +1590,52 @@ int bnx2x_enable_msix(struct bnx2x *bp)
msix_vec++;
}

+ rc = pci_msix_table_size(bp->pdev);
+ if (rc < 0)
+ goto no_msix;
+
+ nvec = min(msix_vec, rc);
+ if (nvec < BNX2X_MIN_MSIX_VEC_CNT(bp))
+ nvec = 1;
+
DP(BNX2X_MSG_SP, "about to request enable msix with %d vectors\n",
msix_vec);

- rc = pci_enable_msix(bp->pdev, &bp->msix_table[0], msix_vec);
+ rc = pci_enable_msix(bp->pdev, &bp->msix_table[0], nvec);
+ if (rc)
+ goto no_msix;

/*
* reconfigure number of tx/rx queues according to available
* MSI-X vectors
*/
- if (rc >= BNX2X_MIN_MSIX_VEC_CNT(bp)) {
- /* how less vectors we will have? */
- int diff = msix_vec - rc;
-
- BNX2X_DEV_INFO("Trying to use less MSI-X vectors: %d\n", rc);
+ if (nvec == 1) {
+ bp->flags |= USING_SINGLE_MSIX_FLAG;

- rc = pci_enable_msix(bp->pdev, &bp->msix_table[0], rc);
+ bp->num_ethernet_queues = 1;
+ bp->num_queues = bp->num_ethernet_queues + bp->num_cnic_queues;
+ } else if (nvec < msix_vec) {
+ /* how less vectors we will have? */
+ int diff = msix_vec - nvec;

- if (rc) {
- BNX2X_DEV_INFO("MSI-X is not attainable rc %d\n", rc);
- goto no_msix;
- }
/*
* decrease number of queues by number of unallocated entries
*/
bp->num_ethernet_queues -= diff;
bp->num_queues = bp->num_ethernet_queues + bp->num_cnic_queues;
+ }

+ if (nvec != msix_vec)
BNX2X_DEV_INFO("New queue configuration set: %d\n",
bp->num_queues);
- } else if (rc > 0) {
- /* Get by with single vector */
- rc = pci_enable_msix(bp->pdev, &bp->msix_table[0], 1);
- if (rc) {
- BNX2X_DEV_INFO("Single MSI-X is not attainable rc %d\n",
- rc);
- goto no_msix;
- }
-
- BNX2X_DEV_INFO("Using single MSI-X vector\n");
- bp->flags |= USING_SINGLE_MSIX_FLAG;
-
- BNX2X_DEV_INFO("set number of queues to 1\n");
- bp->num_ethernet_queues = 1;
- bp->num_queues = bp->num_ethernet_queues + bp->num_cnic_queues;
- } else if (rc < 0) {
- BNX2X_DEV_INFO("MSI-X is not attainable rc %d\n", rc);
- goto no_msix;
- }

bp->flags |= USING_MSIX_FLAG;

return 0;

no_msix:
+ BNX2X_DEV_INFO("MSI-X is not attainable rc %d\n", rc);
+
/* fall to INTx if not enough memory */
if (rc == -ENOMEM)
bp->flags |= DISABLE_MSI_FLAG;
--
1.7.7.6

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