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| author | Jan Glauber <jang@linux.vnet.ibm.com> | 2011-08-03 16:44:17 +0200 |
|---|---|---|
| committer | Heiko Carstens <heiko.carstens@de.ibm.com> | 2011-08-03 16:44:19 +0200 |
| commit | be8d97a540cec5d272b1e08e27741a3c3aa38f66 (patch) | |
| tree | 39fc55cde3cdf81aea341dd1de1d2957988b97b1 /drivers/s390/cio/qdio.h | |
| parent | ed8f37370d83e695c0a4fa5d5fc7a83ecb947526 (diff) | |
| download | linux-be8d97a540cec5d272b1e08e27741a3c3aa38f66.tar.bz2 | |
[S390] qdio: 2nd stage retry on SIGA-W busy conditions
The SIGA-W may return with the busy bit set which means the device was
blocked. The busy loop which retries the SIGA-W for 100us may not be
long enough when running under a heavily loaded hypervisor.
Extend the retry mechanism by adding a longer second stage which retries
the SIGA-W for up to 10s. In difference to the first retry loop the second
stage is using mdelay to stop the cpu between the retries and thereby
avoid additional preassure in on the hypervisor.
If the second stage retry is successfull a device reset is avoided.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio/qdio.h')
| -rw-r--r-- | drivers/s390/cio/qdio.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/s390/cio/qdio.h b/drivers/s390/cio/qdio.h index 7bc643f3f5ab..e5c966462c5a 100644 --- a/drivers/s390/cio/qdio.h +++ b/drivers/s390/cio/qdio.h @@ -14,6 +14,8 @@ #include "chsc.h" #define QDIO_BUSY_BIT_PATIENCE (100 << 12) /* 100 microseconds */ +#define QDIO_BUSY_BIT_RETRY_DELAY 10 /* 10 milliseconds */ +#define QDIO_BUSY_BIT_RETRIES 1000 /* = 10s retry time */ #define QDIO_INPUT_THRESHOLD (500 << 12) /* 500 microseconds */ /* |