reorder write after free checks away from critical region in allocate_small#335
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rdevshp wants to merge 1 commit into
Open
reorder write after free checks away from critical region in allocate_small#335rdevshp wants to merge 1 commit into
rdevshp wants to merge 1 commit into
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jvoisin
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May 27, 2026
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| if (requested_size) { | ||
| write_after_free_check(p, size - canary_size); | ||
| set_canary(metadata, p, size); | ||
| } |
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Don't those operations need to acquired c->lock?
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These operations are done after the c->lock critical region already marked the slot as used with set_used_slot, which means that other concurrent allocations would not touch/allocate this slot.
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In a local multithread benchmark that I ran on x86-64, I was able to get a ~7% speedup with this patch.