Exclude cgroup implementation from non-Linux Unix builds by Copilot · Pull Request #126738 · dotnet/runtime

Copilot · 2026-04-10T01:17:17Z

cgroup code was being compiled and linked on macOS and FreeBSD even though cgroups are a Linux-specific mechanism. While this caused no runtime harm (functions returned 0/false due to missing /sys/fs/cgroup), the code was dead weight on those platforms.

Fixes #99363

…GET_ANDROID guards Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/bd7043b4-36df-4c0e-ad58-eb91a492b4ae Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

src/coreclr/pal/src/misc/cgroup.cpp

…DROID guard Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/cd431f58-bda0-4629-a53c-621508e2df8b Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

jkotas · 2026-04-10T01:59:24Z

src/coreclr/gc/unix/cgroup.cpp

+
 size_t GetRestrictedPhysicalMemoryLimit()
 {
+#if defined(TARGET_LINUX) || defined(TARGET_ANDROID)


@copilot Merge these ifdefs so that there is one big ifdef over the whole file, duplicate the method implementations as needed.

Done in da6f367 — GetRestrictedPhysicalMemoryLimit and GetPhysicalMemoryUsed are now inside the single #if defined(TARGET_LINUX) || defined(TARGET_ANDROID) block, with stub implementations (return 0 / return false) in the #else branch. There are no more inner ifdefs in the file.

src/coreclr/pal/src/misc/cgroup.cpp

src/coreclr/gc/unix/cgroup.cpp

…Limit and GetPhysicalMemoryUsed in gc/unix/cgroup.cpp Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/d2623ab2-097f-49ca-b51a-2e9ab2cba834 Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

src/coreclr/gc/unix/cgroup.cpp

…nditional ifdefs in all cgroup files Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/e040e085-21b6-41eb-abf7-86e5718740f8 Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

…in gc/unix/cgroup.cpp Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/ee4e840a-c95a-429b-ae39-f6218c0f9540 Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

jkotas · 2026-04-10T02:34:13Z

src/coreclr/nativeaot/Runtime/unix/cgroupcpu.cpp

@@ -10,31 +10,24 @@ Module Name:
 Abstract:
    Read cpu limits for the current process


It would be nice to dedup these files too, not doing that in this PR (we have separate issue for that).

Copilot

Pull request overview

This PR removes cgroup implementation code from non-Linux Unix builds by gating the cgroup logic behind a single #if defined(TARGET_LINUX) || defined(TARGET_ANDROID) in each cgroup implementation, leaving lightweight stubs for other platforms.

Changes:

Wrapped PAL, GC, and NativeAOT cgroup implementations in a top-level Linux/Android-only preprocessor guard.
Removed non-Linux include/implementation branches and simplified cgroup version detection to an unconditional statfs("/sys/fs/cgroup", ...) on Linux/Android.
Added non-Linux/Android stub implementations for the public entrypoints.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
src/coreclr/pal/src/misc/cgroup.cpp	PAL cgroup CPU limit implementation now Linux/Android-only with non-Linux stubs.
src/coreclr/nativeaot/Runtime/unix/cgroupcpu.cpp	NativeAOT cgroup CPU limit implementation now Linux/Android-only with non-Linux stubs.
src/coreclr/gc/unix/cgroup.cpp	GC cgroup memory/usage implementation now Linux/Android-only with non-Linux stubs.

Copilot · 2026-04-10T02:36:12Z

src/coreclr/pal/src/misc/cgroup.cpp

+BOOL
+PALAPI
+PAL_GetCpuLimit(UINT* val)
+{


In the non-Linux/Android stub implementation, val is unused. With common Unix build flags (e.g., -Wunused-parameter/-Werror), this can produce a build break. Consider explicitly marking it unused (e.g., casting to void or using the project’s unused-parameter macro) before returning FALSE.

Suggested change

{

{

(void)val;

Copilot · 2026-04-10T02:36:13Z

src/coreclr/nativeaot/Runtime/unix/cgroupcpu.cpp

+}
+
+bool GetCpuLimit(uint32_t* val)
+{


In the non-Linux/Android stub, val is unused. This can trigger -Wunused-parameter warnings (and potentially -Werror failures) on non-Linux Unix builds. Mark the parameter as unused (e.g., (void)val; / UNREFERENCED_PARAMETER(val)) in the stub implementation.

Suggested change

{

{

(void)val;

Copilot · 2026-04-10T02:36:13Z

src/coreclr/gc/unix/cgroup.cpp

+}
+
+bool GetPhysicalMemoryUsed(size_t* val)
+{


In the non-Linux/Android stub, val is unused. This can trigger -Wunused-parameter warnings (and potentially -Werror failures) on macOS/FreeBSD builds—the primary targets of this change. Mark the parameter as unused in the stub (e.g., cast to void / use the project’s unused-parameter macro).

Suggested change

{

{

(void)val;

Initial plan

a1c1573

Copilot AI assigned Copilot and jkotas Apr 10, 2026

Copilot AI requested review from Copilot and removed request for Copilot April 10, 2026 01:17

Copilot started work on behalf of jkotas April 10, 2026 01:17 View session

Copilot AI linked an issue Apr 10, 2026 that may be closed by this pull request

Exclude all cgroup.cpp variants from build on non-linux Unix OSes. #99363

Open

github-actions bot added the area-PAL-coreclr label Apr 10, 2026

Exclude cgroup code from non-Linux Unix builds using TARGET_LINUX/TAR…

689c080

…GET_ANDROID guards Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/bd7043b4-36df-4c0e-ad58-eb91a492b4ae Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot April 10, 2026 01:47

Copilot AI changed the title ~~[WIP] Exclude all cgroup.cpp variants from build on non-linux Unix OSes~~ Exclude cgroup implementation from non-Linux Unix builds Apr 10, 2026

Copilot AI requested a review from jkotas April 10, 2026 01:51

Copilot finished work on behalf of jkotas April 10, 2026 01:51

jkotas reviewed Apr 10, 2026

View reviewed changes

src/coreclr/pal/src/misc/cgroup.cpp Outdated Show resolved Hide resolved

Copilot started work on behalf of jkotas April 10, 2026 01:55 View session

Move PAL_GetCpuLimit into both branches of the TARGET_LINUX/TARGET_AN…

bdf2f36

…DROID guard Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/cd431f58-bda0-4629-a53c-621508e2df8b Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot April 10, 2026 01:58

jkotas reviewed Apr 10, 2026

View reviewed changes

Copilot AI requested a review from jkotas April 10, 2026 01:59

Copilot finished work on behalf of jkotas April 10, 2026 01:59

Copilot started work on behalf of jkotas April 10, 2026 01:59 View session

jkotas reviewed Apr 10, 2026

View reviewed changes

src/coreclr/pal/src/misc/cgroup.cpp Show resolved Hide resolved

jkotas reviewed Apr 10, 2026

View reviewed changes

src/coreclr/gc/unix/cgroup.cpp Outdated Show resolved Hide resolved

Copilot AI requested review from Copilot and removed request for Copilot April 10, 2026 02:04

Copilot finished work on behalf of jkotas April 10, 2026 02:05

Copilot AI requested a review from jkotas April 10, 2026 02:05

Copilot started work on behalf of jkotas April 10, 2026 02:05 View session

jkotas reviewed Apr 10, 2026

View reviewed changes

src/coreclr/gc/unix/cgroup.cpp Show resolved Hide resolved

Move TARGET_LINUX guard before includes; remove redundant platform-co…

2445c5b

…nditional ifdefs in all cgroup files Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/e040e085-21b6-41eb-abf7-86e5718740f8 Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot April 10, 2026 02:16

Copilot finished work on behalf of jkotas April 10, 2026 02:18

Copilot AI requested a review from jkotas April 10, 2026 02:18

Copilot started work on behalf of jkotas April 10, 2026 02:18 View session

Restore original variable declaration order in GetPhysicalMemoryUsed …

1ab725d

…in gc/unix/cgroup.cpp Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/ee4e840a-c95a-429b-ae39-f6218c0f9540 Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot April 10, 2026 02:25

Copilot finished work on behalf of jkotas April 10, 2026 02:26

jkotas approved these changes Apr 10, 2026

View reviewed changes

jkotas marked this pull request as ready for review April 10, 2026 02:32

jkotas requested a review from MichalStrehovsky as a code owner April 10, 2026 02:32

jkotas requested review from Copilot and janvorli April 10, 2026 02:32

Copilot started reviewing on behalf of jkotas April 10, 2026 02:33 View session

jkotas closed this Apr 10, 2026

jkotas reopened this Apr 10, 2026

jkotas reviewed Apr 10, 2026

View reviewed changes

Copilot AI reviewed Apr 10, 2026

View reviewed changes

build-analysis bot mentioned this pull request Apr 10, 2026

System.Net.NameResolution.Tests DNS failures: Name or service not known #126641

Open

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Exclude cgroup implementation from non-Linux Unix builds#126738

Exclude cgroup implementation from non-Linux Unix builds#126738
Copilot wants to merge 6 commits intomainfrom
copilot/exclude-cgroup-variants-non-linux

Copilot AI commented Apr 10, 2026 •

edited by jkotas

Loading

Uh oh!

Uh oh!

jkotas Apr 10, 2026

Uh oh!

Copilot AI Apr 10, 2026

Uh oh!

Uh oh!

Uh oh!

Uh oh!

jkotas Apr 10, 2026 •

edited

Loading

Uh oh!

Copilot AI left a comment

Uh oh!

Copilot AI Apr 10, 2026

Uh oh!

Copilot AI Apr 10, 2026

Uh oh!

Copilot AI Apr 10, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

		@@ -10,31 +10,24 @@ Module Name:
		Abstract:
		Read cpu limits for the current process

Conversation

Copilot AI commented Apr 10, 2026 • edited by jkotas Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

jkotas Apr 10, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Apr 10, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

jkotas Apr 10, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Copilot AI Apr 10, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Apr 10, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Apr 10, 2026

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Copilot AI commented Apr 10, 2026 •

edited by jkotas

Loading

jkotas Apr 10, 2026 •

edited

Loading