• Jan Glauber's avatar
    [S390] qdio: 2nd stage retry on SIGA-W busy conditions · be8d97a5
    Jan Glauber authored
    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: default avatarJan Glauber <jang@linux.vnet.ibm.com>
    Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
    be8d97a5
qdio_main.c 40.9 KB