• David Howells's avatar
    rxrpc: Obtain RTT data by requesting ACKs on DATA packets · 50235c4b
    David Howells authored
    In addition to sending a PING ACK to gain RTT data, we can set the
    RXRPC_REQUEST_ACK flag on a DATA packet and get a REQUESTED-ACK ACK.  The
    ACK packet contains the serial number of the packet it is in response to,
    so we can look through the Tx buffer for a matching DATA packet.
    
    This requires that the data packets be stamped with the time of
    transmission as a ktime rather than having the resend_at time in jiffies.
    
    This further requires the resend code to do the resend determination in
    ktimes and convert to jiffies to set the timer.
    Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
    50235c4b
ar-internal.h 36.5 KB