Fix: Add memfence before unsetting bit #283
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psychocoderHPC
requested changes
Feb 6, 2025
| // before we finish. (The latter scenario might be excluded by other mem_fences in the code.) If a read | ||
| // is pending, the old thread might read data from the new thread leading to inconsistent information | ||
| // in the first thread. | ||
| alpaka::mem_fence(acc, alpaka::memory_scope::Device{}); |
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This fence should be moved into destroy() to guard multi page mode allocation too.
We do not have the issue with bitflips in multi page mode but since mallocMC is a caching allocator we are responsible to guarantee that the user can use the allocated memory without side effects.
| // bitmask itself, if the chunk size (and thereby the extent of the bitmask) changes before we finish. | ||
| // (The latter scenario might be excluded by other mem_fences in the code.) If a read is pending, the old | ||
| // thread might read data from the new thread leading to inconsistent information in the first thread. | ||
| alpaka::mem_fence(acc, alpaka::memory_scope::Device{}); |
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some as I write below, the fence should guard multi page deallocations too.
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psychocoderHPC
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Feb 6, 2025
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Second bug fix for making PIConGPU collisions work.