On 11/15 2013 22:11, Christoph Hellwig wrote: > On Fri, Nov 15, 2013 at 12:29:48PM +0800, Jeff Liu wrote: >> Hi Folks, >> >> This patch is trying to introduce a new list helper to retrieve the >> last entry or return NULL if the list is empty corresponding to it, >> which is inspired by Jiri Pirko's list_first_entry_or_null(). > > How did we end up with the stupid _or_null prefix there? I think the > functionality is useful, but the naming is way to verbose, especially > given that a list_first_entry or list_last_entry that optimizes away > that one check doesn't seem useful. > Instead of encoding detailed semantics in the name a good kerneldoc > comment is way better. When it comes to this point, looks the name is really a bit verbose. And yes, they have the same kernel doc to list_first_entry/list_last_entry. But at rculist.h, we have another similar routine with this suffix, i.e, list_fist_or_null_rcu(). Maybe we can figure out a better name and replace the existing code with it as list_first_entry_or_null() has not yet been widely used, it mainly being used in drivers code as per a grep against linux-next tree. $ grep list_first_entry_or_null -r linux-next ./drivers/acpi/acpi_ipmi.c: driver_data.selected_smi = list_first_entry_or_null( ./drivers/base/regmap/regmap.c: async = list_first_entry_or_null(&map->async_free, ./drivers/base/regmap/regmap.c: async = list_first_entry_or_null(&map->async_free, ./drivers/net/team/team.c: port = list_first_entry_or_null(&team->port_list, ./drivers/net/ethernet/sfc/mcdi.c: async = list_first_entry_or_null( ./drivers/net/ethernet/intel/i40e/i40e_main.c: return list_first_entry_or_null(&vsi->mac_filter_list, ./drivers/net/vxlan.c: rd = list_first_entry_or_null(&f->remotes, struct vxlan_rdst, list); ./drivers/of/irq.c: desc = list_first_entry_or_null(&intc_parent_list, ./fs/xfs/xfs_trans_priv.h: return list_first_entry_or_null(&ailp->xa_ail, struct xfs_log_item, ./net/nfc/digital_core.c: cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd, ./net/nfc/digital_core.c: cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd, Thanks, -Jeff _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
