diff options
| author | Pierre Gondois | 2023-04-14 10:14:49 +0200 |
|---|---|---|
| committer | Sudeep Holla | 2023-04-14 10:13:38 +0100 |
| commit | 7a306e3eabf2b2fd8cffa69b87b32dbf814d79ce (patch) | |
| tree | 399f075ff94d390091eac2fe8cf83c7c5d2495e2 /drivers/base | |
| parent | e103d55465db06c5344201fd5fa11bb19bc479c5 (diff) | |
cacheinfo: Check sib_leaf in cache_leaves_are_shared()
If there is no ACPI/DT information, it is assumed that L1 caches
are private and L2 (and higher) caches are shared. A cache is
'shared' between two CPUs if it is accessible from these two
CPUs.
Each CPU owns a representation (i.e. has a dedicated cacheinfo struct)
of the caches it has access to. cache_leaves_are_shared() tries to
identify whether two representations are designating the same actual
cache.
In cache_leaves_are_shared(), if 'this_leaf' is a L2 cache (or higher)
and 'sib_leaf' is a L1 cache, the caches are detected as shared as
only this_leaf's cache level is checked.
This is leads to setting sib_leaf as being shared with another CPU,
which is incorrect as this is a L1 cache.
Check 'sib_leaf->level'. Also update the comment as the function is
called when populating 'shared_cpu_map'.
Fixes: f16d1becf96f ("cacheinfo: Use cache identifiers to check if the caches are shared if available")
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230414081453.244787-2-pierre.gondois@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/cacheinfo.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 6e0a44bad305..ba14c7872e4a 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -38,11 +38,10 @@ static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf, { /* * For non DT/ACPI systems, assume unique level 1 caches, - * system-wide shared caches for all other levels. This will be used - * only if arch specific code has not populated shared_cpu_map + * system-wide shared caches for all other levels. */ if (!(IS_ENABLED(CONFIG_OF) || IS_ENABLED(CONFIG_ACPI))) - return !(this_leaf->level == 1); + return (this_leaf->level != 1) && (sib_leaf->level != 1); if ((sib_leaf->attributes & CACHE_ID) && (this_leaf->attributes & CACHE_ID)) |