diff options
| author | Julian Wiedmann <jwi@linux.ibm.com> | 2019-08-23 11:48:48 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-08-24 16:39:18 -0700 |
| commit | 313dc689b16c08b081939ee9b87dac3736c780e3 (patch) | |
| tree | 473f175b8e96dd7f404e10872d2353ce4e895838 /drivers/s390/cio/qdio_main.c | |
| parent | 7c47f5afdeef763599f1ae22d29b8c3904c58315 (diff) | |
| download | linux-313dc689b16c08b081939ee9b87dac3736c780e3.tar.bz2 | |
s390/qdio: let drivers opt-out from Output Queue scanning
If a driver wants to use the new Output Queue poll code, then the qdio
layer must disable its internal Queue scanning. Let the driver select
this mode by passing a special scan_threshold of 0.
As the scan_threshold is the same for all Output Queues, also move it
into the main qdio_irq struct. This allows for fast opt-out checking, a
driver is expected to operate either _all_ or none of its Output Queues
in polling mode.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/s390/cio/qdio_main.c')
| -rw-r--r-- | drivers/s390/cio/qdio_main.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c index 5efba0d29190..5b63c505a2f7 100644 --- a/drivers/s390/cio/qdio_main.c +++ b/drivers/s390/cio/qdio_main.c @@ -880,7 +880,7 @@ static inline void qdio_check_outbound_pci_queues(struct qdio_irq *irq) struct qdio_q *out; int i; - if (!pci_out_supported(irq)) + if (!pci_out_supported(irq) || !irq->scan_threshold) return; for_each_output_queue(irq, out, i) @@ -973,7 +973,7 @@ static void qdio_int_handler_pci(struct qdio_irq *irq_ptr) } } - if (!pci_out_supported(irq_ptr)) + if (!pci_out_supported(irq_ptr) || !irq_ptr->scan_threshold) return; for_each_output_queue(irq_ptr, q, i) { @@ -1528,6 +1528,7 @@ set: static int handle_outbound(struct qdio_q *q, unsigned int callflags, int bufnr, int count) { + const unsigned int scan_threshold = q->irq_ptr->scan_threshold; unsigned char state = 0; int used, rc = 0; @@ -1566,8 +1567,12 @@ static int handle_outbound(struct qdio_q *q, unsigned int callflags, rc = qdio_kick_outbound_q(q, 0); } + /* Let drivers implement their own completion scanning: */ + if (!scan_threshold) + return rc; + /* in case of SIGA errors we must process the error immediately */ - if (used >= q->u.out.scan_threshold || rc) + if (used >= scan_threshold || rc) qdio_tasklet_schedule(q); else /* free the SBALs in case of no further traffic */ |