Fixing asan error on mpmc queue

[MaciejKaszynski]

Fixes the ASAN error with the MPMCConcurrentQueue

• Fixes mpmc_concurrent_queue_test excluded from ASan/UBSan due to fake-stack alignment false positive #241

Using manual padding instead of alignas so that ASAN's fake stack can correctly.
Setting the alignment on the class itself didn't fix the asan error as it would just set the alignment for the class itself.

[github-actions]

License Check Results

🚀 The license check job ran with the Bazel command:

bazel run --lockfile_mode=error //:license-check

Status: ⚠️ Needs Review

Click to expand output

[License Check Output]
Extracting Bazel installation...
Starting local Bazel server (8.6.0) and connecting to it...
INFO: Invocation ID: db80632d-326b-4e34-99d6-df26b08cdfa6
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Analyzing: target //:license-check (84 packages loaded, 10 targets configured)

Analyzing: target //:license-check (139 packages loaded, 1041 targets configured)

Analyzing: target //:license-check (152 packages loaded, 5208 targets configured)

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Analyzing: target //:license-check (161 packages loaded, 8240 targets configured)

Analyzing: target //:license-check (164 packages loaded, 8271 targets configured)

Analyzing: target //:license-check (164 packages loaded, 8271 targets configured)

Analyzing: target //:license-check (164 packages loaded, 8271 targets configured)

Analyzing: target //:license-check (167 packages loaded, 10159 targets configured)

Analyzing: target //:license-check (168 packages loaded, 10283 targets configured)

INFO: Analyzed target //:license-check (169 packages loaded, 10409 targets configured).
[12 / 16] JavaToolchainCompileClasses external/rules_java+/toolchains/platformclasspath_classes; 0s disk-cache, processwrapper-sandbox ... (2 actions running)
[14 / 16] JavaToolchainCompileBootClasspath external/rules_java+/toolchains/platformclasspath.jar; 0s disk-cache, processwrapper-sandbox
[15 / 16] Building license.check.license_check.jar (); 0s disk-cache, multiplex-worker
INFO: Found 1 target...
Target //:license.check.license_check up-to-date:
  bazel-bin/license.check.license_check
  bazel-bin/license.check.license_check.jar
INFO: Elapsed time: 24.832s, Critical Path: 2.51s
INFO: 16 processes: 12 internal, 3 processwrapper-sandbox, 1 worker.
INFO: Build completed successfully, 16 total actions
INFO: Running command line: bazel-bin/license.check.license_check ./formatted.txt <args omitted>
usage: org.eclipse.dash.licenses.cli.Main [-batch <int>] [-cd <url>]
       [-confidence <int>] [-ef <url>] [-excludeSources <sources>] [-help] [-lic
       <url>] [-project <shortname>] [-repo <url>] [-review] [-summary <file>]
       [-timeout <seconds>] [-token <token>]

[github-actions]

The created documentation from the pull request is available at: docu-html

[VukPavicRTRK]

Nice fix for the ASan false positive. One thing to call out: CacheLinePaddedAtomic<T> preserves cache-line size but not cache-line alignment, so it weakens the original false-sharing guarantee provided by alignas(CacheLineSize). At minimum, the comments on m_head, m_tail, and m_stopped should be updated since they're no longer strictly "aligned on their own cache line."

[MaciejKaszynski]

Nice fix for the ASan false positive. One thing to call out: CacheLinePaddedAtomic<T> preserves cache-line size but not cache-line alignment, so it weakens the original false-sharing guarantee provided by alignas(CacheLineSize). At minimum, the comments on m_head, m_tail, and m_stopped should be updated since they're no longer strictly "aligned on their own cache line."

So I have done a benchmark and seen that false sharing doesn't actually cause any performance drawbacks. I have committed the benchmark and made the members not aligned at all .

[S-MOHAMD]

Please lnk corresponding issue/bug.
see: https://docs.github.com/en/issues/tracking-your-work-with-issues/using-issues/linking-a-pull-request-to-an-issue