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authorVishal Verma <vishal.l.verma@intel.com>2022-11-17 02:37:37 +0300
committerDan Williams <dan.j.williams@intel.com>2022-11-19 10:55:40 +0300
commit48d4180939e12c4bd2846f984436d895bb9699ed (patch)
tree30a105ea3bbea28a4bb48626503f4fe1faab3920 /drivers/acpi/numa
parent14f16d47561ba9249efc6c2db9d47ed56841f070 (diff)
downloadlinux-48d4180939e12c4bd2846f984436d895bb9699ed.tar.xz
ACPI: HMAT: Fix initiator registration for single-initiator systems
In a system with a single initiator node, and one or more memory-only 'target' nodes, the memory-only node(s) would fail to register their initiator node correctly. i.e. in sysfs: # ls /sys/devices/system/node/node0/access0/targets/ node0 Where as the correct behavior should be: # ls /sys/devices/system/node/node0/access0/targets/ node0 node1 This happened because hmat_register_target_initiators() uses list_sort() to sort the initiator list, but the sort comparision function (initiator_cmp()) is overloaded to also set the node mask's bits. In a system with a single initiator, the list is singular, and list_sort elides the comparision helper call. Thus the node mask never gets set, and the subsequent search for the best initiator comes up empty. Add a new helper to consume the sorted initiator list, and generate the nodemask, decoupling it from the overloaded initiator_cmp() comparision callback. This prevents the singular list corner case naturally, and makes the code easier to follow as well. Cc: <stable@vger.kernel.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Chris Piper <chris.d.piper@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: https://lore.kernel.org/r/20221116-acpi_hmat_fix-v2-2-3712569be691@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/acpi/numa')
-rw-r--r--drivers/acpi/numa/hmat.c26
1 files changed, 20 insertions, 6 deletions
diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index 144a84f429ed..6cceca64a6bc 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -562,17 +562,26 @@ static int initiator_cmp(void *priv, const struct list_head *a,
{
struct memory_initiator *ia;
struct memory_initiator *ib;
- unsigned long *p_nodes = priv;
ia = list_entry(a, struct memory_initiator, node);
ib = list_entry(b, struct memory_initiator, node);
- set_bit(ia->processor_pxm, p_nodes);
- set_bit(ib->processor_pxm, p_nodes);
-
return ia->processor_pxm - ib->processor_pxm;
}
+static int initiators_to_nodemask(unsigned long *p_nodes)
+{
+ struct memory_initiator *initiator;
+
+ if (list_empty(&initiators))
+ return -ENXIO;
+
+ list_for_each_entry(initiator, &initiators, node)
+ set_bit(initiator->processor_pxm, p_nodes);
+
+ return 0;
+}
+
static void hmat_register_target_initiators(struct memory_target *target)
{
static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
@@ -609,7 +618,10 @@ static void hmat_register_target_initiators(struct memory_target *target)
* initiators.
*/
bitmap_zero(p_nodes, MAX_NUMNODES);
- list_sort(p_nodes, &initiators, initiator_cmp);
+ list_sort(NULL, &initiators, initiator_cmp);
+ if (initiators_to_nodemask(p_nodes) < 0)
+ return;
+
if (!access0done) {
for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
loc = localities_types[i];
@@ -643,7 +655,9 @@ static void hmat_register_target_initiators(struct memory_target *target)
/* Access 1 ignores Generic Initiators */
bitmap_zero(p_nodes, MAX_NUMNODES);
- list_sort(p_nodes, &initiators, initiator_cmp);
+ if (initiators_to_nodemask(p_nodes) < 0)
+ return;
+
for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
loc = localities_types[i];
if (!loc)