1. 09 Sep, 2010 9 commits
    • Andy Grover's avatar
      RDS: Explicitly allocate rm in sendmsg() · fc445084
      Andy Grover authored
      r_m_copy_from_user used to allocate the rm as well as kernel
      buffers for the data, and then copy the data in. Now, sendmsg()
      allocates the rm, although the data buffer alloc still happens
      in r_m_copy_from_user.
      
      SGs are still allocated with rm, but now r_m_alloc_sgs() is
      used to reserve them. This allows multiple SG lists to be
      allocated from the one rm -- this is important once we also
      want to alloc our rdma sgl from this pool.
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      fc445084
    • Andy Grover's avatar
      RDS: cleanup/fix rds_rdma_unuse · 3ef13f3c
      Andy Grover authored
      First, it looks to me like the atomic_inc is wrong.
      We should be decrementing refcount only once here, no? It's
      already being done by the mr_put() at the end.
      
      Second, simplify the logic a bit by bailing early (with a warning)
      if !mr.
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      3ef13f3c
    • Andy Grover's avatar
      RDS: break out rdma and data ops into nested structs in rds_message · e779137a
      Andy Grover authored
      Clearly separate rdma-related variables in rm from data-related ones.
      This is in anticipation of adding atomic support.
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      e779137a
    • Andy Grover's avatar
      RDS: cleanup: remove "== NULL"s and "!= NULL"s in ptr comparisons · 8690bfa1
      Andy Grover authored
      Favor "if (foo)" style over "if (foo != NULL)".
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      8690bfa1
    • Andy Grover's avatar
      RDS: move rds_shutdown_worker impl. to rds_conn_shutdown · 2dc39357
      Andy Grover authored
      This fits better in connection.c, rather than threads.c.
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      2dc39357
    • Andy Grover's avatar
      RDS: Fix locking in send on m_rs_lock · 9de0864c
      Andy Grover authored
      Do not nest m_rs_lock under c_lock
      
      Disable interrupts in {rdma,atomic}_send_complete
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      9de0864c
    • Andy Grover's avatar
      RDS: Rewrite rds_send_drop_to() for clarity · 7c82eaf0
      Andy Grover authored
      This function has been the source of numerous bugs; it's just
      too complicated. Simplified to nest spinlocks cleanly within
      the second loop body, and kick out early if there are no
      rms to drop.
      
      This will be a little slower because conn lock is grabbed for
      each entry instead of "caching" the lock across rms, but this
      should be entirely irrelevant to fastpath performance.
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      7c82eaf0
    • Tina Yang's avatar
      RDS: Fix corrupted rds_mrs · 35b52c70
      Tina Yang authored
      On second look at this bug (OFED #2002), it seems that the
      collision is not with the retransmission queue (packet acked
      by the peer), but with the local send completion.  A theoretical
      sequence of events (from time t0 to t3) is thought to be as
      follows,
      
      Thread #1
      t0:
          sock_release
          rds_release
          rds_send_drop_to /* wait on send completion */
      t2:
          rds_rdma_drop_keys()   /* destroy & free all mrs */
      
      Thread #2
      t1:
          rds_ib_send_cq_comp_handler
          rds_ib_send_unmap_rm
          rds_message_unmapped   /* wake up #1 @ t0 */
      t3:
          rds_message_put
          rds_message_purge
          rds_mr_put   /* memory corruption detected */
      
      The problem with the rds_rdma_drop_keys() is it could
      remove a mr's refcount more than its due (i.e. repeatedly
      as long as it still remains in the tree (mr->r_refcount > 0)).
      Theoretically it should remove only one reference - reference
      by the tree.
      
              /* Release any MRs associated with this socket */
              while ((node = rb_first(&rs->rs_rdma_keys))) {
                      mr = container_of(node, struct rds_mr, r_rb_node);
                      if (mr->r_trans == rs->rs_transport)
                              mr->r_invalidate = 0;
                      rds_mr_put(mr);
              }
      
      I think the correct way of doing it is to remove the mr from
      the tree and rds_destroy_mr it first, then a rds_mr_put()
      to decrement its reference count by one.  Whichever thread
      holds the last reference will free the mr via rds_mr_put().
      Signed-off-by: default avatarTina Yang <tina.yang@oracle.com>
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      35b52c70
    • Andy Grover's avatar
      RDS: Fix BUG_ONs to not fire when in a tasklet · 9e2effba
      Andy Grover authored
      in_interrupt() is true in softirqs. The BUG_ONs are supposed
      to check for if irqs are disabled, so we should use
      BUG_ON(irqs_disabled()) instead, duh.
      Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
      9e2effba
  2. 07 Sep, 2010 31 commits