On 12/03/2009 10:59 AM, Boaz Harrosh wrote: > On 12/01/2009 05:36 PM, Boaz Harrosh wrote: >> >> So libosd has decided to sacrifice some code simplicity for the sake of >> a clean API. One of these things is the possibility for users to call >> osd_end_request, in any condition at any state. This opens up some >> problems with calling blk_put_request when out-side of the completion >> callback but calling __blk_put_request when detecting a from-completion >> state. >> >> The current hack was working just fine until exofs decided to operate on >> all devices in parallel and wait for the sum of the requests, before >> deallocating all osd-requests at once. There are two new possible cases >> 1. All request in a group are deallocated as part of the last request's >> async-done, request_queue is locked. >> 2. All request in a group where executed asynchronously, but >> de-allocation was delayed to after the async-done, in the context of >> another thread. Async execution but request_queue is not locked. >> >> The solution I chose was to separate the deallocation of the osd_request >> which has the information users need, from the deallocation of the >> internal(2) requests which impose the locking problem. The internal >> block-requests are freed unconditionally inside the async-done-callback, >> when we know the queue is always locked. If at osd_end_request time we >> still have a bock-request, then we know it did not come from within an >> async-done-callback and we can call the regular blk_put_request. >> >> The internal requests were used for carrying error information after >> execution. This information is now copied to osd_request members for >> later analysis by user code. >> >> The external API and behaviour was unchanged, except now it really >> supports what was previously advertised. >> >> Reported-by: Vineet Agarwal <checkout.vineet@xxxxxxxxx> >> Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx> > > James Hi > > Linus has locked the 2.6.32 Kernel. I absolutely must have this patch > submitted in this merge window. The all of exofs patches depend on it. > Please submit ASAP > > Boaz > James I'm reminding you of this patch. If you do not have another round of patches for the merge window, then please submit it through rc-fixes. It is a very important bug-fix for exofs. Thanks Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
