fix check on shrEnergyM0TotalAccum in HCAL-Alpaka kernel [14_0_X]

[missirol]

backport of #45452

PR description:

From the description of #45452:

This PR fixes how the values in the array shrEnergyM0TotalAccum in shared memory are used in one of the HCAL-Alpaka kernels.

The per-channel value of shrEnergyM0TotalAccum[lch] is filled summing values across "samples", and this is done concurrently on GPU. The issue is that the same value is accessed before threads are synchronised. In the examples tested offline, this tends to return almost-always the correct results on GPU, but incorrect ones on CPU (or rather, "serial_sync" backend) as the samples in the latter case are processed one at the time.

This change and related validation (see below) were discussed offline last week with @fwyzard and @kakwok.

PR validation:

See the validation section of #45452.

If this PR is a backport, please specify the original PR and why you need to backport that PR. If this PR will be backported, please specify to which release cycle the backport is meant for:

#45452

Fix relevant to 2024 data-taking.

[cmsbuild]

A new Pull Request was created by @missirol for CMSSW_14_0_X.

It involves the following packages:

• RecoLocalCalo/HcalRecProducers (reconstruction)

@cmsbuild, @jfernan2, @mandrenguyen can you please review it and eventually sign? Thanks.
@abdoulline, @apsallid, @bsunanda, @mariadalfonso, @youyingli this is something you requested to watch as well.
@antoniovilela, @rappoccio, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

• Backported from fix check on shrEnergyM0TotalAccum in HCAL-Alpaka kernel #45452

[cmsbuild]

cms-bot internal usage

[jfernan2]

assign heterogeneous

[cmsbuild]

New categories assigned: heterogeneous

@fwyzard,@makortel you have been requested to review this Pull request/Issue and eventually sign? Thanks

[cmsbuild]

Pull request #45453 was updated. @cmsbuild, @fwyzard, @jfernan2, @makortel, @mandrenguyen can you please check and sign again.

[cmsbuild]

Pull request #45453 was updated. @cmsbuild, @fwyzard, @jfernan2, @makortel, @mandrenguyen can you please check and sign again.

[fwyzard]

+heterogeneous

[fwyzard]

please test

[fwyzard]

urgent

I understood that the release managers will not be available later, so we should get this in the next 14.0.x patch release sooner rather than later.

[cmsbuild]

Pull request #45453 was updated. @jfernan2, @mandrenguyen can you please check and sign again.

[cmsbuild]

Pull request #45453 was updated. @cmsbuild, @fwyzard, @jfernan2, @makortel, @mandrenguyen can you please check and sign again.

[jfernan2]

+1

[cmsbuild]

+1

Size: This PR adds an extra 28KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-0f1ce9/40408/summary.html
COMMIT: 57e9df5
CMSSW: CMSSW_14_0_X_2024-07-15-1100/el8_amd64_gcc12
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/45453/40408/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 112 lines from the logs
• Reco comparison results: 52 differences found in the comparisons
• DQMHistoTests: Total files compared: 48
• DQMHistoTests: Total histograms compared: 3342828
• DQMHistoTests: Total failures: 12
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3342796
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 47 files compared)
• Checked 202 log files, 165 edm output root files, 48 DQM output files
• TriggerResults: no differences found

[fwyzard]

+heterogeneous

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_14_0_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_14_1_X is complete. This pull request will now be reviewed by the release team before it's merged. @rappoccio, @antoniovilela, @mandrenguyen, @sextonkennedy (and backports should be raised in the release meeting by the corresponding L2)

[rappoccio]

+1