x86: Fix slight bug in shared_per_thread cache size calculation.

After:
```
    commit af992e7abd
    Author: Noah Goldstein <goldstein.w.n@gmail.com>
    Date:   Wed Jun 7 13:18:01 2023 -0500

        x86: Increase `non_temporal_threshold` to roughly `sizeof_L3 / 4`
```

Split `shared` (cumulative cache size) from `shared_per_thread` (cache
size per socket), the `shared_per_thread` *can* be slightly off from
the previous calculation.

Previously we added `core` even if `threads_l2` was invalid, and only
used `threads_l2` to divide `core` if it was present. The changed
version only included `core` if `threads_l2` was valid.

This change restores the old behavior if `threads_l2` is invalid by
adding the entire value of `core`.
Reviewed-by: DJ Delorie <dj@redhat.com>
This commit is contained in:
Noah Goldstein 2023-07-17 23:14:33 -05:00
parent 2037f8ad01
commit 47f7472178

View File

@ -614,8 +614,8 @@ get_common_cache_info (long int *shared_ptr, long int * shared_per_thread_ptr, u
/* Account for non-inclusive L2 and L3 caches. */
if (!inclusive_cache)
{
if (threads_l2 > 0)
shared_per_thread += core / threads_l2;
long int core_per_thread = threads_l2 > 0 ? (core / threads_l2) : core;
shared_per_thread += core_per_thread;
shared += core;
}