On 7/16/19 3:28 PM, Gerd Rausch wrote:
In the context of FRMR (ib_frmr.c): Memory regions make it onto the "clean_list" via "rds_ib_flush_mr_pool", after the memory region has been posted for invalidation via "rds_ib_post_inv". At that point in time, "fr_state" may still be in state "FRMR_IS_INUSE", since the only place where "fr_state" transitions to "FRMR_IS_FREE" is in "rds_ib_mr_cqe_handler", which is triggered by a tasklet. So in case we notice that "fr_state != FRMR_IS_FREE" (see below), we wait for "fr_inv_done" to trigger with a maximum of 10msec. Then we check again, and only put the memory region onto the drop_list (via "rds_ib_free_frmr") in case the situation remains unchanged. This avoids the problem of memory-regions bouncing between "clean_list" and "drop_list" before they even have a chance to be properly invalidated. Signed-off-by: Gerd Rausch <gerd.rausch@xxxxxxxxxx> ---
Thanks for the update. Acked-by: Santosh Shilimkar <santosh.shilimkar@xxxxxxxxxx>
