netmap error on -CURRENT with em and igb

[Giuseppe Lettieri]

Hi all,

the "Operation not permitted" is coming from iflib_netmap_register:

	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
	...
	IFDI_INIT(ctx);	// for igb it calls em_if_init()
	...
	return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);

the last line is meant to check that the initialization was successful,
but em_if_init() is not setting IFF_DRV_RUNNING.

Note that the iflib_netmap_register code, and the other netmap register 
functions which it mimicks, have other issues:

- in case of failure on NIOCREGIF, they leaves the NETMAP_ON flag set 
even if the netmap data structures are deleted;
- the 1 was intended as a generic indication of failure, but it 
translates to the rather confusing EPERM;
- they check IFF_DRV_RUNNING flag outside of the lock; I don't know it 
this is safe or not.

I can prepare a patch fixing these issues, but I don't know wether 
em_if_init() is supposed to set the IFF_DRV_RUNNING flag or not.

Cheers,
Giuseppe

Il 16/02/2017 09:35, Eggert, Lars ha scritto:
> Hi,
>
> I can't put em or igb interfaces into netmap mode on a recent -CURRENT (ix interfaces work on the same machines). Here are the pkt-gen and dmesg outputs:
>
> # sudo sysctl dev.netmap.admode=1
> # sudo sysctl dev.netmap.verbose=1
>
> # sudo ./pkt-gen -i em1
> 790.411737 main [2274] interface is em1
> 790.411753 main [2397] running on 1 cpus (have 20)
> 790.411823 extract_ip_range [369] range is 10.0.0.1:0 to 10.0.0.1:0
> 790.411828 extract_ip_range [369] range is 10.1.0.1:0 to 10.1.0.1:0
> 790.625117 nm_open [898] NIOCREGIF failed: Operation not permitted em1
> 790.625126 main [2479] Unable to open netmap:em1: Operation not permitted
> 790.625129 main [2560] aborting
>
> dmesg:
> 790.411868 [1776] netmap_interp_ringid      em1: tx [0,2) rx [0,2) id 0
> 790.419431 [ 551] nm_mem_assign_group       iommu_group 0
> 790.425548 [1148] netmap_config_obj_allocator objsize 1024 clustsize 4096 objects 4
> 790.434368 [1148] netmap_config_obj_allocator objsize 36864 clustsize 36864 objects 1
> 790.443390 [1148] netmap_config_obj_allocator objsize 2048 clustsize 4096 objects 2
> 790.452219 [1270] netmap_finalize_obj_allocator Pre-allocated 25 clusters (4/100KB) for 'netmap_if'
> 790.463605 [1270] netmap_finalize_obj_allocator Pre-allocated 200 clusters (36/7200KB) for 'netmap_ring'
> 790.534919 [1270] netmap_finalize_obj_allocator Pre-allocated 81920 clusters (4/327680KB) for 'netmap_buf'
> 790.546113 [1377] netmap_mem_finalize_all   interfaces 100 KB, rings 7200 KB, buffers 320 MB
> 790.555873 [1380] netmap_mem_finalize_all   Free buffers: 163838
> 790.605325 [1831] netmap_mem_global_deref   active = 0
> 790.612967 [ 949] netmap_close              dev 0xfffff8000a4d7c00 fflag 0x20003 devtype 8192 td 0xfffff8000b899000
>
> # sudo ./pkt-gen -i igb1
> 094.077695 main [2274] interface is igb1
> 094.077711 main [2397] running on 1 cpus (have 10)
> 094.077822 extract_ip_range [369] range is 10.0.0.1:0 to 10.0.0.1:0
> 094.077827 extract_ip_range [369] range is 10.1.0.1:0 to 10.1.0.1:0
> 094.280311 nm_open [898] NIOCREGIF failed: Operation not permitted igb1
> 094.280319 main [2479] Unable to open netmap:igb1: Operation not permitted
> 094.280323 main [2560] aborting
>
> dmesg:
> 094.077866 [1776] netmap_interp_ringid      igb1: tx [0,8) rx [0,8) id 0
> 094.085425 [ 551] nm_mem_assign_group       iommu_group 0
> 094.091449 [1148] netmap_config_obj_allocator objsize 1024 clustsize 4096 objects 4
> 094.100125 [1148] netmap_config_obj_allocator objsize 36864 clustsize 36864 objects 1
> 094.109004 [1148] netmap_config_obj_allocator objsize 2048 clustsize 4096 objects 2
> 094.117705 [1270] netmap_finalize_obj_allocator Pre-allocated 25 clusters (4/100KB) for 'netmap_if'
> 094.128918 [1270] netmap_finalize_obj_allocator Pre-allocated 200 clusters (36/7200KB) for 'netmap_ring'
> 094.199456 [1270] netmap_finalize_obj_allocator Pre-allocated 81920 clusters (4/327680KB) for 'netmap_buf'
> 094.210482 [1377] netmap_mem_finalize_all   interfaces 100 KB, rings 7200 KB, buffers 320 MB
> 094.220078 [1380] netmap_mem_finalize_all   Free buffers: 163838
> 094.260201 [1831] netmap_mem_global_deref   active = 0
> 094.268364 [ 949] netmap_close              dev 0xfffff8000a453000 fflag 0x20003 devtype 8192 td 0xfffff80014d45000
>
> Lars
>


-- 
Dr. Ing. Giuseppe Lettieri
Dipartimento di Ingegneria della Informazione
Universita' di Pisa
Largo Lucio Lazzarino 1, 56122 Pisa - Italy
Ph. : (+39) 050-2217.649 (direct) .599 (switch)
Fax : (+39) 050-2217.600
e-mail: g.lettieri at iet.unipi.it