On 11/13/06, David Miller <davem@xxxxxxxxxxxxx> wrote:
From: "Arnaldo Carvalho de Melo" <arnaldo.melo@xxxxxxxxx> Date: Fri, 10 Nov 2006 16:32:16 -0200 > On 11/10/06, James Morris <jmorris@xxxxxxxxx> wrote: > > On Fri, 10 Nov 2006, James Morris wrote: > > > > > I wonder if this facility can be integrated more generally into the kernel > > > protocol which people are developing. > > > > Ugh, editor screwup. That was meant to be > > > > I wonder if this facility can be integrated more generally into the kernel > > as a kernel hacking option, as this is not the only protocol which people > > are developing. > > > > See: > http://www.erg.abdn.ac.uk/users/gerrit/dccp/patch-backlog/09a_release_ctl_socket_at_exit.diff > > This one requires a bit more thinking, so I'm postponing it for now to > get the simple bits in Gerrit's patch queue cherrypicked and sent for > Dave. One possible way to handle this is to flag certain sockets such that no refrence counting is done for them against the module. It is an indication that the module will take care of such sockets on cleanup. It seems that this would limit the cost to a test at socket create and destroy time.
Yes, but this is not the case currently with Gerrit's proposed patch, I'm postponing it for now, as one has to be very very careful to monitor the TW sockets with iproute2's ss before rmmoding with --force, have to revisit the old unload hack to combine its ideas with SCTP/Gerrit's approach, the old one was ugly, but at least refused to unload before all the TW sockets were gone. - Arnaldo [root@qemu ~]# rmmod dccp_ipv4 ERROR: Module dccp_ipv4 is in use by [unsafe] [root@qemu ~]# rmmod --force dccp_ipv4 [ 128.264180] slab error in kmem_cache_destroy(): cache `tw_sock_DCCP': Can't free all objects [ 128.265284] [<c0141ea7>] kmem_cache_destroy+0x77/0xd0 [ 128.266133] [<c0201dcf>] proto_unregister+0x8f/0xb0 [ 128.267222] [<d085005c>] dccp_v4_exit+0x3c/0x5b [dccp_ipv4] [ 128.268050] [<c0128458>] sys_delete_module+0x158/0x1d0 [ 128.268527] [<c0269ada>] do_page_fault+0x4ea/0x640 [ 128.269014] [<c0102abf>] syscall_call+0x7/0xb [ 128.269472] ======================= [root@qemu ~]# rmmod dccp [ 141.267175] slab error in kmem_cache_destroy(): cache `dccp_bind_bucket': Can't free all objects [ 141.268392] [<c0141ea7>] kmem_cache_destroy+0x77/0xd0 [ 141.268950] [<d0847e93>] dccp_fini+0x63/0x70 [dccp] [ 141.270046] [<c0128458>] sys_delete_module+0x158/0x1d0 [ 141.270530] [<c013b6e4>] do_munmap+0x1c4/0x230 [ 141.270964] [<c0102abf>] syscall_call+0x7/0xb [ 141.271414] ======================= Followed by: <BIG SNIP> [ 147.347021] ======================= [ 147.359334] Code: c3 08 e9 69 ff ff ff eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 90 55 89 cd 57 56 89 c6 53 8d 04 ca 83 ec 08 8b 10 89 e7 89 14 24 <89> 62 04 8b 50 04 89 22 89 54 24 04 89 00 8b 14 24 89 40 04 39 [ 147.395025] EIP: [<c0115b05>] cascade+0x15/0x60 SS:ESP 0068:c0304fa4 [ 147.403619] <0>Kernel panic - not syncing: Fatal exception in interrupt [ 147.482149] - To unsubscribe from this list: send the line "unsubscribe dccp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
