On 4/3/24 2:37 AM, Song, Xiongwei wrote: >> >> >> It could be tempting to use >= instead of > to achieve the same effect but >> that would have unintended performance effects that would best be evaluated >> separately. > > I can run a test to measure Amean changes. But in terms of x86 assembly, there > should not be extra instructions with ">=". > > Did a simple test, for ">=" it uses "jle" instruction, while "jl" instruction is used for ">". > No more instructions involved. So there should not be performance effects on x86. Right, I didn't mean the code of the test, but how the difference of the comparison affects how many cpu partial slabs would be put on the cpu partial list here. > Thanks, > Xiongwei > >> >> > >> > + put_cpu_partial(s, slab, 0); >> > + stat(s, CPU_PARTIAL_NODE); >> > + partial_slabs++; >> > + >> > + if (partial_slabs > slub_get_cpu_partial(s) / 2) >> > + break; >> > } >> > spin_unlock_irqrestore(&n->list_lock, flags); >> > return partial; >
