Refactor representation of thread local state. #751
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nwf
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nwf
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nwf
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Only found time to make it into "Restrict ThreadAlloc usage to globalalloc", but so far so great. Thanks for nwfifying the commit stack. :D |
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src/snmalloc/mem/localalloc.h
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| return self->alloc_not_small<zero_mem, CheckInitDefault>(size); | ||
| }, | ||
| size, | ||
| this); |
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It's a bit of a pity that something so formulaic can't, AFAIK, be templated away.
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The check init code was tightly integrated into LocalAllocator. This commit pull that code out into ThreadAlloc, and passes a template parameter into the remaining LocalAllocator to perform the relevant TLS manipulations. This removes some of the awkward layering around register_clean_up.
Fully disable lotsofthreads test Need to investigate if the test is unreliable, or we have actually regressed perf. A quick mimalloc-bench didn't show any regressions.
This introduces one additional branch on when processing a batch of messages, but it is likely to only be hit when a lot of messages are processed.
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This combines the notion of CoreAlloc, LocalAlloc and LocalCache into a single class. Previously, these were separated so that a more complex structure would be stored directly in the TLS. This however, proved to be bad for compatibility if the allocator is part of the libc implementation. This commit collapses all the stages of the allocator into a single class. This simplifies the sequencing and overall is a nice reduction in complexity.
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Change thread local state to be a single pointer to a backend allocated structure. Previously, the TLS contained a complex structure, but that didn't interact well with loading numerous copies at once.