On Tue, Jan 20, 2009 at 12:29:30PM +1100, Greg Banks wrote: > > As mentioned in the recent discussion on NFS trace points on the NFS & > SystemTap mailing lists. This patch allows field support staff and > kernel developers debug kernel problems, by enabling them to treat > dprintks as precise trace points rather than syslog spamming tools. > > This is a forward ported (from 2.6.16), updated, and split version > of a patch that has been used in SGI's internal development tree for > the last few months. The very first version of this was used about > eighteen months ago when debugging NFS/RDMA, which has an enormous > number of dprintks and no other way to debug it. > > Jason Baron suggested I post it here for review and contrast with > his dynamic dprintk feature. > yes, these two patch sets are very similar in the problem that they are addressing. For me, one of the core differences, is that 'dprintk' has per-debug statement control, while my solution, 'dynamic debug' has a more per-module focused control. 'dprintk' thus checks a different variable per-debug line to see if its enabled. On the other hand 'dynamic debug' can check 1 global variable (in the most common cases), to see if its enabled or not. I think we can layer per-line check on top of the 1 global variable check and have a more efficient solution that still allows for fine-grained debugging. 'dprintk' also has a richer user interface, which allows for file, line, module, and statement control. Thus, I think Greg and I can work together and combine the best features of both patches. We will re-post a combined solution. thanks, -Jason -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
