diff options
author | Jon Mason <jon.mason@intel.com> | 2013-04-19 00:59:44 (GMT) |
---|---|---|
committer | Jon Mason <jon.mason@intel.com> | 2013-11-20 16:57:34 (GMT) |
commit | e8aeb60c389c2aa48d345bcf717f8cb7edf67680 (patch) | |
tree | 3610f55a47e8f0bc722397ec8063c9a4f4091f9b /drivers/ntb/ntb_hw.c | |
parent | 78958433db077b339f3a039890148561086574e4 (diff) | |
download | linux-e8aeb60c389c2aa48d345bcf717f8cb7edf67680.tar.xz |
NTB: Disable interrupts and poll under high load
Disable interrupts and poll under high load
Signed-off-by: Jon Mason <jon.mason@intel.com>
Diffstat (limited to 'drivers/ntb/ntb_hw.c')
-rw-r--r-- | drivers/ntb/ntb_hw.c | 42 |
1 files changed, 37 insertions, 5 deletions
diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c index 80505ae..170e8e6 100644 --- a/drivers/ntb/ntb_hw.c +++ b/drivers/ntb/ntb_hw.c @@ -141,6 +141,24 @@ void ntb_unregister_event_callback(struct ntb_device *ndev) ndev->event_cb = NULL; } +static void ntb_irq_work(unsigned long data) +{ + struct ntb_db_cb *db_cb = (struct ntb_db_cb *)data; + int rc; + + rc = db_cb->callback(db_cb->data, db_cb->db_num); + if (rc) + tasklet_schedule(&db_cb->irq_work); + else { + struct ntb_device *ndev = db_cb->ndev; + unsigned long mask; + + mask = readw(ndev->reg_ofs.ldb_mask); + clear_bit(db_cb->db_num * ndev->bits_per_vector, &mask); + writew(mask, ndev->reg_ofs.ldb_mask); + } +} + /** * ntb_register_db_callback() - register a callback for doorbell interrupt * @ndev: pointer to ntb_device instance @@ -155,7 +173,7 @@ void ntb_unregister_event_callback(struct ntb_device *ndev) * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx, - void *data, void (*func)(void *data, int db_num)) + void *data, int (*func)(void *data, int db_num)) { unsigned long mask; @@ -166,6 +184,10 @@ int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx, ndev->db_cb[idx].callback = func; ndev->db_cb[idx].data = data; + ndev->db_cb[idx].ndev = ndev; + + tasklet_init(&ndev->db_cb[idx].irq_work, ntb_irq_work, + (unsigned long) &ndev->db_cb[idx]); /* unmask interrupt */ mask = readw(ndev->reg_ofs.ldb_mask); @@ -194,6 +216,8 @@ void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx) set_bit(idx * ndev->bits_per_vector, &mask); writew(mask, ndev->reg_ofs.ldb_mask); + tasklet_disable(&ndev->db_cb[idx].irq_work); + ndev->db_cb[idx].callback = NULL; } @@ -955,12 +979,16 @@ static irqreturn_t bwd_callback_msix_irq(int irq, void *data) { struct ntb_db_cb *db_cb = data; struct ntb_device *ndev = db_cb->ndev; + unsigned long mask; dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq, db_cb->db_num); - if (db_cb->callback) - db_cb->callback(db_cb->data, db_cb->db_num); + mask = readw(ndev->reg_ofs.ldb_mask); + set_bit(db_cb->db_num * ndev->bits_per_vector, &mask); + writew(mask, ndev->reg_ofs.ldb_mask); + + tasklet_schedule(&db_cb->irq_work); /* No need to check for the specific HB irq, any interrupt means * we're connected. @@ -976,12 +1004,16 @@ static irqreturn_t xeon_callback_msix_irq(int irq, void *data) { struct ntb_db_cb *db_cb = data; struct ntb_device *ndev = db_cb->ndev; + unsigned long mask; dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq, db_cb->db_num); - if (db_cb->callback) - db_cb->callback(db_cb->data, db_cb->db_num); + mask = readw(ndev->reg_ofs.ldb_mask); + set_bit(db_cb->db_num * ndev->bits_per_vector, &mask); + writew(mask, ndev->reg_ofs.ldb_mask); + + tasklet_schedule(&db_cb->irq_work); /* On Sandybridge, there are 16 bits in the interrupt register * but only 4 vectors. So, 5 bits are assigned to the first 3 |