diff mbox series

[v5,07/19] cacheinfo: Use cache identifiers to check if the caches are shared if available

Message ID 20220627165047.336669-8-sudeep.holla@arm.com (mailing list archive)
State New, archived
Headers show
Series arch_topology: Updates to add socket support and fix cluster ids | expand

Commit Message

Sudeep Holla June 27, 2022, 4:50 p.m. UTC 
The cache identifiers is an optional property on most of the platforms.
The presence of one must be indicated by the CACHE_ID valid bit in the
attributes.

We can use the cache identifiers provided by the firmware to check if
any two cpus share the same cache instead of relying on the fw_token
generated and set in the OS.

Link: https://lore.kernel.org/r/20220621192034.3332546-8-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/base/cacheinfo.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
index 2aa9e8e341b7..167abfa6f37d 100644
--- a/drivers/base/cacheinfo.c
+++ b/drivers/base/cacheinfo.c
@@ -44,6 +44,10 @@  static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
 	if (!(IS_ENABLED(CONFIG_OF) || IS_ENABLED(CONFIG_ACPI)))
 		return !(this_leaf->level == 1);
 
+	if ((sib_leaf->attributes & CACHE_ID) &&
+	    (this_leaf->attributes & CACHE_ID))
+		return sib_leaf->id == this_leaf->id;
+
 	return sib_leaf->fw_token == this_leaf->fw_token;
 }
 
@@ -56,7 +60,8 @@  bool last_level_cache_is_valid(unsigned int cpu)
 
 	llc = per_cpu_cacheinfo_idx(cpu, cache_leaves(cpu) - 1);
 
-	return !!llc->fw_token;
+	return (llc->attributes & CACHE_ID) || !!llc->fw_token;
+
 }
 
 bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y)