Ar Llu, 2006-09-18 am 20:05 -0500, ysgrifennodd Olof Johansson: > On Mon, 18 Sep 2006 15:56:37 -0700 "Dan Williams" <[email protected]> wrote: > op.src_type = PG; op.src = pg; > op.dest_type = BUF; op.dest = buf; > op.len = len; > dma_async_commit(chan, op); At OLS Linus suggested it should distinguish between sync and async events for locking reasons. if(dma_async_commit(foo) == SYNC_COMPLETE) { finalise_stuff(); } else /* will call foo->callback(foo->dev_id) */ because otherwise you have locking complexities - the callback wants to take locks to guard the object it works on but if it is called synchronously - eg if hardware is busy and we fall back - it might deadlock with the caller of dmaa_async_foo() who also needs to hold the lock. Alan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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