[PATCH 0/6] perf: Reduce stack usage (and misc bits)

[Peter Zijlstra]

Hi,

Steve reported an NMI stack overflow when running perf and function tracing
together. Thomas found that we had 4 copies of struct perf_sample_data
on-stack.

These here patches reduce that to 2 copies and half the size of it.

So just for perf_sample_data we go from 4*384=1536 to 2*192=384 bytes of stack.
Also remove one struct pt_regs instance from __intel_pmu_pebs_event(); it has
another instance in struct x86_perf_regs which I haven't yet managed to
offload.

Perf seems to still work... :-)