perf: Make AUX software double buffering great again

Commit 5768402fd9c6e87 ("perf/ring_buffer: Use high order allocations for
AUX buffers optimistically") overlooked the fact that the previous one page
granularity of the AUX buffer provided an implicit double buffering
capability to the PMU driver, which went away when the entire buffer became
one high-order page.

Always make the full-trace mode AUX allocation at least two-part to preserve
the previous behavior and allow the implicit double buffering to continue.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 5768402fd9c6e87 ("perf/ring_buffer: Use high order allocations for AUX buffers optimistically")
Reported-by: Ammy Yi <ammy.yi@intel.com>
1 file changed