On 10/2/2018 4:57 AM, Sudeep Holla wrote:
On Thu, Sep 27, 2018 at 08:57:57PM -0600, Jeffrey Hugo wrote:
The type of a cache might not be specified by architectural mechanisms (ie
system registers), but its type might be specified in the PPTT. In this
case, we should populate the type of the cache, rather than leave it
undefined.
This fixes the issue where the cacheinfo driver will not populate sysfs
for such caches, resulting in the information missing from utilities like
lstopo and lscpu, thus degrading the user experience.
Fixes: 2bd00bcd73e5 (ACPI/PPTT: Add Processor Properties Topology Table parsing)
Reported-by: Vijaya Kumar K <vkilari@xxxxxxxxxxxxxx>
Signed-off-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
---
drivers/acpi/pptt.c | 30 +++++++++++++-----------------
1 file changed, 13 insertions(+), 17 deletions(-)
diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
index d1e26cb..38ac30e 100644
--- a/drivers/acpi/pptt.c
+++ b/drivers/acpi/pptt.c
@@ -357,25 +357,15 @@ static void update_cache_properties(struct cacheinfo *this_leaf,
struct acpi_pptt_cache *found_cache,
struct acpi_pptt_processor *cpu_node)
{
- int valid_flags = 0;
-
this_leaf->fw_token = cpu_node;
- if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID) {
+ if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID)
this_leaf->size = found_cache->size;
- valid_flags++;
- }
- if (found_cache->flags & ACPI_PPTT_LINE_SIZE_VALID) {
+ if (found_cache->flags & ACPI_PPTT_LINE_SIZE_VALID)
this_leaf->coherency_line_size = found_cache->line_size;
- valid_flags++;
- }
- if (found_cache->flags & ACPI_PPTT_NUMBER_OF_SETS_VALID) {
+ if (found_cache->flags & ACPI_PPTT_NUMBER_OF_SETS_VALID)
this_leaf->number_of_sets = found_cache->number_of_sets;
- valid_flags++;
- }
- if (found_cache->flags & ACPI_PPTT_ASSOCIATIVITY_VALID) {
+ if (found_cache->flags & ACPI_PPTT_ASSOCIATIVITY_VALID)
this_leaf->ways_of_associativity = found_cache->associativity;
- valid_flags++;
- }
if (found_cache->flags & ACPI_PPTT_WRITE_POLICY_VALID) {
switch (found_cache->attributes & ACPI_PPTT_MASK_WRITE_POLICY) {
case ACPI_PPTT_CACHE_POLICY_WT:
@@ -402,11 +392,17 @@ static void update_cache_properties(struct cacheinfo *this_leaf,
}
}
/*
- * If the above flags are valid, and the cache type is NOCACHE
- * update the cache type as well.
+ * If cache type is NOCACHE, then the cache hasn't been specified
+ * via other mechanisms. Update the type if a cache type has been
+ * provided.
+ *
+ * Note, we assume such caches are unified based on conventional system
+ * design and known examples. Significant work is required elsewhere to
+ * fully support data/instruction only type caches which are only
+ * specified in PPTT.
*/
if (this_leaf->type == CACHE_TYPE_NOCACHE &&
- valid_flags == PPTT_CHECKED_ATTRIBUTES)
I don't think we use PPTT_CHECKED_ATTRIBUTES elsewhere.
If so, can we drop that ?
Other than that:
Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>
Whoops, you are right. For some reason I thought that came from the
standard ACPICA definitions. Let me drop that.
--
Jeffrey Hugo
Qualcomm Datacenter Technologies as an affiliate of Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.
