Messages in this thread | | | Date | Mon, 17 Aug 2009 01:21:50 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH 2/7] kfifo: move out spinlock |
| |
On Mon, 17 Aug 2009 09:08:29 +0100 Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> > > Those wrappers happen to be called kfifo_get and kfifo_put > > > > Those names are wrong. > > We've had them for years
So? It's been wrong for years. This is a chance to fix it.
> > They're wrong because they are the spinlock-specific variant. What are > > we going to call the mutex_lock-specific variant? > > There isn't one.
Oh come on.
> > > > > > But the happens-to-use-spin_lock functions shouldn't be called > > > > kfifo_get(), because that steals namespace from the unlocked functions, > > > > and makes the naming for the happens-to-use-mutex_lock functions look > > > > weird. > > > > > > All over the kernel unlocked function versions have a leading _ name. > > > It's the kernel convention. > > > > tisn't. radix-tree, rbrtee, idr, list_head, prio_tree, flex_array - > > none of them use that convention. > > Some random "10 second grep" examples, and this is also used more > generally for the "without extra goo" variant of things > > __set_special_pids > __sysrq_put_key_op > __sysrq_get_key_op > __handle_sysrq > __audit_getname > __audit_inode > __audit_node_child > > and the without extra goo use includes such minor classics > __get_user > __put_user > > the kernel contains lots and lots of > > __foo() > > foo() > { > spin_lock(bar); > __foo() > spin_unlock(bar) > }
None of those functions are part of general container libraries. All the ones I mentioned _are_ part of general container libraries.
Plus, as I've said enty en times and keep getting ignored: the current naming is wrong. The generic kfifo_get() should not be assuming that the caller wants spinlock-based locking.
> > > The other thing I must say I dislike about these patches is the > > > gratuitious 'let's rename all the functions' approach it takes. The kfifo > > > API is documented, used and random API of the year type changes mess > > > stuff up and cause unneeded churn. > > > > It fixes naming mistakes. Long-term it is the correct thing to do. > > Best to do it now before we get more callers. > > Why don't we fix all the really dumb naming mistakes then - things like > the chrdev interfaces ? Massive churn, massive confusion. Patches are > always being rejected (and rightfully so) for causing such messes.
These patches don't make a mess. Stefani has already fixed all callers in a small number of patches.
> And remember: its very hard to fix existing API documentation and books. > It's doubly dangerous (and IMHO a complete no-no) to change the API of an > interface if you don't change it such that old code will not reliably get > a compile time failure.
The patchet will cause unmigrated code to fail to build, won't it?
| |