On Tue, Feb 01, 2022 at 02:00:09PM -0600, Bob Pearson wrote: > as currently written the local variable has a kref obtained from the kref_get in > rxe_lookup_mcg or the kref_init in rxe_init_mcg if it is newly created. This ref is > dropped when the local variable goes out of scope. To protect the mcg when it is > inactive at least one more ref is required. I take an additional ref in rxe_get_mcg > if the mcg is created to protect the pointer in the red-black tree. This persists > for the lifetime of the object until it is destroyed when it is removed from the tree > and has the longest scope. This is enough to keep the object alive (it works fine BTW.) > It is also possible to take ref's representing the pointers in the list but they > wouldn't add anything. I think I got it upside down, but OK this works for me. What was kbuild complaining about? > On the other point. Is it standard practice to user ERRPTRs in the > kernel rather than return arguments? I seem to have seen both styles > used but it may have been my imagination. I don't have any > preference here but sometimes choose one or the other in parallel > flows to make comparable routines in the flows have similar > interfaces. Always prefer errptrs. Jason
