Skip to content

add contiguous inside rmsnorm kernel #95

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
jikunshang merged 1 commit into from
Dec 16, 2025
Merged

add contiguous inside rmsnorm kernel #95

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions csrc/layernorm.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -204,6 +204,12 @@ void rms_norm(
torch::Tensor& input,
torch::Tensor& weight,
double epsilon) {
TORCH_CHECK(out.is_contiguous());
if (input.stride(-1) != 1) {
input = input.contiguous();
}
TORCH_CHECK(input.stride(-1) == 1);
Copy link

Copilot AI Dec 12, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The check at line 211 is redundant. After the contiguous() call on line 209, the stride(-1) is guaranteed to be 1. This assertion will never fail and can be removed.

Suggested change
TORCH_CHECK(input.stride(-1) == 1);

Copilot uses AI. Check for mistakes.
TORCH_CHECK(weight.is_contiguous());
VLLM_DISPATCH_FLOATING_TYPES(
input.scalar_type(), "call_rms_norm_kernel", [&] {
vllm::call_rms_norm_kernel<scalar_t>(out, input, weight, epsilon);
Comment on lines +208 to 215
Copy link

Copilot AI Dec 12, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Modifying the input parameter silently may lead to unexpected behavior for callers. Consider either making input non-const to signal this modification is possible, or document this behavior clearly, or make a copy to avoid mutating the caller's reference.

Suggested change
if (input.stride(-1) != 1) {
input = input.contiguous();
}
TORCH_CHECK(input.stride(-1) == 1);
TORCH_CHECK(weight.is_contiguous());
VLLM_DISPATCH_FLOATING_TYPES(
input.scalar_type(), "call_rms_norm_kernel", [&] {
vllm::call_rms_norm_kernel<scalar_t>(out, input, weight, epsilon);
auto input_ = input;
if (input_.stride(-1) != 1) {
input_ = input_.contiguous();
}
TORCH_CHECK(input_.stride(-1) == 1);
TORCH_CHECK(weight.is_contiguous());
VLLM_DISPATCH_FLOATING_TYPES(
input_.scalar_type(), "call_rms_norm_kernel", [&] {
vllm::call_rms_norm_kernel<scalar_t>(out, input_, weight, epsilon);

Copilot uses AI. Check for mistakes.
Expand Down