On Tue, Jun 01, 2021 at 12:45:16PM +0300, Adrian Hunter wrote:

On 1/06/21 12:17 pm, Peter Zijlstra wrote:

quoted

On Tue, Jun 01, 2021 at 12:07:31PM +0300, Adrian Hunter wrote:

quoted

__sync_xxx_compare_and_swap is out-of-date now. This page:

https://gcc.gnu.org/onlinedocs/gcc/_005f_005fsync-Builtins.html#g_t_005f_005fsync-Builtins

recommends '__atomic' builtins instead.

perf doesn't seem to use that.

I guess we could drop support for the compat case; add validation:

"Error, 32-bit perf cannot record AUX area traces from a 64-bit kernel.
Please use a 64-bit version of perf instead."

For AUX, possibly, sadly the exact same problem exists for the normal
buffer IIRC.