CuDNN 7 cases added, warnings removed

[gineshidalgo99]

Added some cuDNN 7 support.

Now it works without any warnings in both cuDNN 7 and cuDNN < 7.

Otherwise, it pop ups the following warnings in cuDNN 7 (I'm enabling all warnings):

In file included from ./include/caffe/util/device_alternate.hpp:40:0,
                 from ./include/caffe/common.hpp:19,
                 from ./include/caffe/blob.hpp:8,
                 from ./include/caffe/layers/loss_layer.hpp:6,
                 from src/caffe/layers/loss_layer.cpp:3:
./include/caffe/util/cudnn.hpp: In function ‘const char* cudnnGetErrorString(cudnnStatus_t)’:
./include/caffe/util/cudnn.hpp:21:10: warning: enumeration value ‘CUDNN_STATUS_RUNTIME_IN_PROGRESS’ not handled in switch [-Wswitch]
   switch (status) {
          ^
./include/caffe/util/cudnn.hpp:21:10: warning: enumeration value ‘CUDNN_STATUS_RUNTIME_FP_OVERFLOW’ not handled in switch [-Wswitch]
CXX src/caffe/layers/absval_layer.cpp
In file included from ./include/caffe/util/device_alternate.hpp:40:0,
                 from ./include/caffe/common.hpp:19,
                 from ./include/caffe/blob.hpp:8,
                 from ./include/caffe/layer.hpp:8,
                 from ./include/caffe/layers/parameter_layer.hpp:6,
                 from src/caffe/layers/parameter_layer.cpp:1:

The code difference is adding these cases:

#if CUDNN_VERSION_MIN(7, 0, 0)
    case CUDNN_STATUS_RUNTIME_IN_PROGRESS:
      return "CUDNN_STATUS_RUNTIME_IN_PROGRESS";
    case CUDNN_STATUS_RUNTIME_FP_OVERFLOW:
      return "CUDNN_STATUS_RUNTIME_FP_OVERFLOW";
#endif

Highly tested and it's being currently used in OpenPose

[gineshidalgo99]

Travis builds worked nicely. I only added the case for cuDNN > 7. And I used #if #endif in order to avoid crashing in cuDNN < 7 (tested in 5.1, 6 and 7)

[gineshidalgo99]

Side note: I've been using it for the last 2 weeks (and I have 2 servers, one with cuDNN 7 and one with 5.1), and the same code works nicely in both versions.

[Noiredd]

@shelhamer We've got 3 PRs for cuDNN 7 support: this one (which was first), #5879 (which also adds grouped convolution) and #5972 (which also updates installation instructions and Travis dependencies). Personally, I think the combination of the latter two would be best - what do you think?

[Noiredd]

I decided to merge #5972 instead, as it also changes Travis to test with cuDNN 7. Offering any support for the new version is too important to keep us waiting for review of #5879.

Still, thank you for your contribution @gineshidalgo99!

[cheyuanxiaozi]

when using cudnn 7 , the variables in 'cudnn.h' are not defined in all of cudnn layers. Is there anyone see this error?