Messages in this thread | | | From | Lai Jiangshan <> | Date | Thu, 17 Mar 2022 00:18:12 +0800 | Subject | Re: [PATCH V3 4/7] x86/entry: move PUSH_AND_CLEAR_REGS out of error_entry |
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On Wed, Mar 16, 2022 at 11:07 PM Peter Zijlstra <peterz@infradead.org> wrote:
> > So I don't much care about the orc data, that's only used when > unwinding, a relatively rare occasion, anyway. But the text increase > does bother me a little, this can blow up I$ misses on syscall heavy > workloads.
It has nothing to do with the syscall.
It does add a lot in I$. But it is fortunate that the footprint is the same (before and after the patch) for a single exception vector. For example heavy #PF workloads.
Footprint will increase after this patch when two or more exception vectors happen heavily at the same time, for example when #PF and timer are occurring heavily.
We can put PUSH_AND_CLEAR_REGS in a single function to reduce the footprint for heavy multi-exception workloads. What do you think?
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