• David Howells's avatar
    FS-Cache: Permit cache retrieval ops to be interrupted in the initial wait phase · 5753c441
    David Howells authored
    Permit the operations to retrieve data from the cache or to allocate space in
    the cache for future writes to be interrupted whilst they're waiting for
    permission for the operation to proceed.  Typically this wait occurs whilst the
    cache object is being looked up on disk in the background.
    
    If an interruption occurs, and the operation has not yet been given the
    go-ahead to run, the operation is dequeued and cancelled, and control returns
    to the read operation of the netfs routine with none of the requested pages
    having been read or in any way marked as known by the cache.
    
    This means that the initial wait is done interruptibly rather than
    uninterruptibly.
    
    In addition, extra stats values are made available to show the number of ops
    cancelled and the number of cache space allocations interrupted.
    Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
    5753c441
operation.c 13 KB