From b08dbfede911833c7ed8cb5e88e86639f265496a Mon Sep 17 00:00:00 2001
From: laurent <laurent.mazare@gmail.com>
Date: Wed, 2 Oct 2024 23:09:18 +0200
Subject: [PATCH] Fix for cudnn bf16 conv2d.

---
 candle-core/src/cuda_backend/cudnn.rs | 11 ++++++-----
 candle-core/src/cuda_backend/mod.rs   | 13 ++++++++-----
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/candle-core/src/cuda_backend/cudnn.rs b/candle-core/src/cuda_backend/cudnn.rs
index d604863d3..f5b4db902 100644
--- a/candle-core/src/cuda_backend/cudnn.rs
+++ b/candle-core/src/cuda_backend/cudnn.rs
@@ -26,6 +26,7 @@ impl From<cudarc::driver::DriverError> for crate::Error {
 
 pub(crate) fn launch_conv2d<
     T: DeviceRepr + WithDType + ValidAsZeroBits + cudarc::cudnn::CudnnDataType,
+    Y: cudarc::cudnn::CudnnDataType,
 >(
     src: &CudaView<T>,
     src_l: &crate::Layout,
@@ -48,7 +49,7 @@ pub(crate) fn launch_conv2d<
         }
         c
     })?;
-    let conv = cudnn.create_conv2d::<T>(
+    let conv = cudnn.create_conv2d::<Y>(
         /* pad */ [params.padding as i32, params.padding as i32],
         /* stride */ [params.stride as i32, params.stride as i32],
         /* dilation */ [params.dilation as i32, params.dilation as i32],
@@ -62,18 +63,18 @@ pub(crate) fn launch_conv2d<
     ];
     // Note that `src` already starts at the proper offset.
     let x = if src_l.is_contiguous() {
-        cudnn.create_4d_tensor(
+        cudnn.create_4d_tensor::<T>(
             cudarc::cudnn::sys::cudnnTensorFormat_t::CUDNN_TENSOR_NCHW,
             x_shape,
         )?
     } else {
         let s = src_l.stride();
-        cudnn.create_4d_tensor_ex(
+        cudnn.create_4d_tensor_ex::<T>(
             x_shape,
             [s[0] as i32, s[1] as i32, s[2] as i32, s[3] as i32],
         )?
     };
-    let w = cudnn.create_4d_filter(
+    let w = cudnn.create_4d_filter::<T>(
         cudarc::cudnn::sys::cudnnTensorFormat_t::CUDNN_TENSOR_NCHW,
         [
             params.c_out as i32,
@@ -83,7 +84,7 @@ pub(crate) fn launch_conv2d<
         ],
     )?;
     let (w_out, h_out) = (params.out_w() as i32, params.out_h() as i32);
-    let y = cudnn.create_4d_tensor(
+    let y = cudnn.create_4d_tensor::<T>(
         cudarc::cudnn::sys::cudnnTensorFormat_t::CUDNN_TENSOR_NCHW,
         [params.b_size as i32, params.c_out as i32, h_out, w_out],
     )?;
diff --git a/candle-core/src/cuda_backend/mod.rs b/candle-core/src/cuda_backend/mod.rs
index 07bb1785d..f14e00d53 100644
--- a/candle-core/src/cuda_backend/mod.rs
+++ b/candle-core/src/cuda_backend/mod.rs
@@ -1522,7 +1522,7 @@ impl BackendStorage for CudaStorage {
                 let inp = &inp.slice(inp_l.start_offset()..);
                 let k = &k.slice(kernel_l.start_offset()..);
                 let mut out = unsafe { device.alloc::<u8>(dst_el) }.w()?;
-                crate::cudnn::launch_conv2d::<u8>(inp, inp_l, k, &mut out, params, &device)
+                crate::cudnn::launch_conv2d::<u8, u8>(inp, inp_l, k, &mut out, params, &device)
                     .map_err(crate::Error::wrap)?;
                 S::U8(out)
             }
@@ -1530,7 +1530,10 @@ impl BackendStorage for CudaStorage {
                 let inp = &inp.slice(inp_l.start_offset()..);
                 let k = &k.slice(kernel_l.start_offset()..);
                 let mut out = unsafe { device.alloc::<bf16>(dst_el) }.w()?;
-                crate::cudnn::launch_conv2d::<bf16>(inp, inp_l, k, &mut out, params, &device)
+                // Only PSEUDO_BFLOAT16_CONFIG is supported in cudnn, there is no "true bfloat16"
+                // version.
+                // https://docs.nvidia.com/deeplearning/cudnn/latest/api/cudnn-cnn-library.html#id88
+                crate::cudnn::launch_conv2d::<bf16, f32>(inp, inp_l, k, &mut out, params, &device)
                     .map_err(crate::Error::wrap)?;
                 S::BF16(out)
             }
@@ -1538,7 +1541,7 @@ impl BackendStorage for CudaStorage {
                 let inp = &inp.slice(inp_l.start_offset()..);
                 let k = &k.slice(kernel_l.start_offset()..);
                 let mut out = unsafe { device.alloc::<f16>(dst_el) }.w()?;
-                crate::cudnn::launch_conv2d::<f16>(inp, inp_l, k, &mut out, params, &device)
+                crate::cudnn::launch_conv2d::<f16, f16>(inp, inp_l, k, &mut out, params, &device)
                     .map_err(crate::Error::wrap)?;
                 S::F16(out)
             }
@@ -1546,7 +1549,7 @@ impl BackendStorage for CudaStorage {
                 let inp = &inp.slice(inp_l.start_offset()..);
                 let k = &k.slice(kernel_l.start_offset()..);
                 let mut out = unsafe { device.alloc::<f32>(dst_el) }.w()?;
-                crate::cudnn::launch_conv2d::<f32>(inp, inp_l, k, &mut out, params, &device)
+                crate::cudnn::launch_conv2d::<f32, f32>(inp, inp_l, k, &mut out, params, &device)
                     .map_err(crate::Error::wrap)?;
                 S::F32(out)
             }
@@ -1554,7 +1557,7 @@ impl BackendStorage for CudaStorage {
                 let inp = &inp.slice(inp_l.start_offset()..);
                 let k = &k.slice(kernel_l.start_offset()..);
                 let mut out = unsafe { device.alloc::<f64>(dst_el) }.w()?;
-                crate::cudnn::launch_conv2d::<f64>(inp, inp_l, k, &mut out, params, &device)
+                crate::cudnn::launch_conv2d::<f64, f64>(inp, inp_l, k, &mut out, params, &device)
                     .map_err(crate::Error::wrap)?;
                 S::F64(out)
             }