# Re: \[PATCH net-next 02/14\] tcp: use windowed min filter library for TCP min\_rtt estimation

- From: kbuild test robot \<hidden\>
- Date: 2016-09-16 19:21:23 
- List: netdev
- Page: https://ratatoskr.run/netdev/2016/09/11029172
- Thread: https://ratatoskr.run/netdev/2016/09/11029154/t.md

```text
Hi Neal,

[auto build test ERROR on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Neal-Cardwell/tcp-BBR-congestion-control-algorithm/20160917-025323
config: x86_64-randconfig-x006-201637 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

>> net/ipv4/tcp_cdg.c:59:8: error: redefinition of 'struct minmax'
    struct minmax {
           ^~~~~~
   In file included from include/linux/tcp.h:22:0,
                    from include/net/tcp.h:24,
                    from net/ipv4/tcp_cdg.c:30:
   include/linux/win_minmax.h:17:8: note: originally defined here
    struct minmax {
           ^~~~~~

vim +59 net/ipv4/tcp_cdg.c

2b0a8c9e Kenneth Klette Jonassen 2015-06-10  43  module_param(window, int, 0444);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  44  MODULE_PARM_DESC(window, "gradient window size (power of two <= 256)");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  45  module_param(backoff_beta, uint, 0644);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  46  MODULE_PARM_DESC(backoff_beta, "backoff beta (0-1024)");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  47  module_param(backoff_factor, uint, 0644);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  48  MODULE_PARM_DESC(backoff_factor, "backoff probability scale factor");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  49  module_param(hystart_detect, uint, 0644);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  50  MODULE_PARM_DESC(hystart_detect, "use Hybrid Slow start "
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  51  		 "(0: disabled, 1: ACK train, 2: delay threshold, 3: both)");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  52  module_param(use_ineff, uint, 0644);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  53  MODULE_PARM_DESC(use_ineff, "use ineffectual backoff detection (threshold)");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  54  module_param(use_shadow, bool, 0644);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  55  MODULE_PARM_DESC(use_shadow, "use shadow window heuristic");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  56  module_param(use_tolerance, bool, 0644);
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  57  MODULE_PARM_DESC(use_tolerance, "use loss tolerance heuristic");
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  58  
2b0a8c9e Kenneth Klette Jonassen 2015-06-10 @59  struct minmax {
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  60  	union {
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  61  		struct {
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  62  			s32 min;
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  63  			s32 max;
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  64  		};
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  65  		u64 v64;
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  66  	};
2b0a8c9e Kenneth Klette Jonassen 2015-06-10  67  };

:::::: The code at line 59 was first introduced by commit
:::::: 2b0a8c9eee81882fc0001ccf6d9af62cdc682f9e tcp: add CDG congestion control

:::::: TO: Kenneth Klette Jonassen [ref]
:::::: CC: David S. Miller [ref]

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
```

## Attachments

- [.config.gz](https://ratatoskr.run/netdev/2016/09/11029172/attachment/0) (application/gzip, 26892 bytes)