You are right, cq_lock will result into dead lock. Should there be a additional compl_handler spin_lock? I was measuring performance impact for adding it, and, irq_save() and irq_restore() variant showed additional 200 cycles, which I believe should be o.k.?
Parav -----Original Message----- From: Steve Wise [mailto:sw...@opengridcomputing.com] Sent: Thursday, October 20, 2011 9:52 PM To: Roland Dreier Cc: Pandit, Parav; kuma...@chelsio.com; linux-rdma@vger.kernel.org; d...@chelsio.com Subject: Re: [PATCH] RDMA/cxgb4: Unblock reads on comp_channel On 10/20/2011 11:06 AM, Roland Dreier wrote: > On Thu, Oct 20, 2011 at 2:11 AM,<parav.pan...@emulex.com> wrote: >> http://lxr.linux.no/#linux+v3.0.4/Documentation/infiniband/core_locking.txt >> >> Line no 66 to 97 states that - at a given point of time, there should be >> only one callback per CQ should be active. >> Is this ensured? >> >> compl_handler() is invoked from multiple places flush_qp() and >> post_qp_event() to my mind. > Yes, does look like an issue with this patch :( > And I think this bug exists in the T3 driver too. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
