base/node / acpi: Change 'node_hmem_attrs' to 'access_coordinates'

Dan Williams suggested changing the struct 'node_hmem_attrs' to
'access_coordinates' [1]. The struct is a container of r/w-latency and
r/w-bandwidth numbers. Moving forward, this container will also be used by
CXL to store the performance characteristics of each link hop in
the PCIE/CXL topology. So, where node_hmem_attrs is just the access
parameters of a memory-node, access_coordinates applies more broadly
to hardware topology characteristics. The observation is that seemed like
an exercise in having the application identify "where" it falls on a
spectrum of bandwidth and latency needs. For the tuple of
read/write-latency and read/write-bandwidth, "coordinates" is not a perfect
fit. Sometimes it is just conveying values in isolation and not a
"location" relative to other performance points, but in the end this data
is used to identify the performance operation point of a given memory-node.
[2]

Link: http://lore.kernel.org/r/64471313421f7_1b66294d5@dwillia2-xfh.jf.intel.com.notmuch/
Link: https://lore.kernel.org/linux-cxl/645e6215ee0de_1e6f2945e@dwillia2-xfh.jf.intel.com.notmuch/
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/170319615734.2212653.15319394025985499185.stgit@djiang5-mobl3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index 9ef5f1bdcfdbcf5d5f09827f4e5fae7e56f6e10b..83bc2b69401bfb8ef0b72123d80ba2282abe240f 100644 (file)
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -63,7 +63,7 @@ struct memory_target {
        unsigned int memory_pxm;
        unsigned int processor_pxm;
        struct resource memregions;
-       struct node_hmem_attrs hmem_attrs[2];
+       struct access_coordinate coord[2];
        struct list_head caches;
        struct node_cache_attrs cache_attrs;
        bool registered;
@@ -228,24 +228,24 @@ static void hmat_update_target_access(struct memory_target *target,
 {
        switch (type) {
        case ACPI_HMAT_ACCESS_LATENCY:
-               target->hmem_attrs[access].read_latency = value;
-               target->hmem_attrs[access].write_latency = value;
+               target->coord[access].read_latency = value;
+               target->coord[access].write_latency = value;
                break;
        case ACPI_HMAT_READ_LATENCY:
-               target->hmem_attrs[access].read_latency = value;
+               target->coord[access].read_latency = value;
                break;
        case ACPI_HMAT_WRITE_LATENCY:
-               target->hmem_attrs[access].write_latency = value;
+               target->coord[access].write_latency = value;
                break;
        case ACPI_HMAT_ACCESS_BANDWIDTH:
-               target->hmem_attrs[access].read_bandwidth = value;
-               target->hmem_attrs[access].write_bandwidth = value;
+               target->coord[access].read_bandwidth = value;
+               target->coord[access].write_bandwidth = value;
                break;
        case ACPI_HMAT_READ_BANDWIDTH:
-               target->hmem_attrs[access].read_bandwidth = value;
+               target->coord[access].read_bandwidth = value;
                break;
        case ACPI_HMAT_WRITE_BANDWIDTH:
-               target->hmem_attrs[access].write_bandwidth = value;
+               target->coord[access].write_bandwidth = value;
                break;
        default:
                break;
@@ -681,7 +681,7 @@ static void hmat_register_target_cache(struct memory_target *target)
 static void hmat_register_target_perf(struct memory_target *target, int access)
 {
        unsigned mem_nid = pxm_to_node(target->memory_pxm);
-       node_set_perf_attrs(mem_nid, &target->hmem_attrs[access], access);
+       node_set_perf_attrs(mem_nid, &target->coord[access], access);
 }
 
 static void hmat_register_target_devices(struct memory_target *target)
@@ -765,7 +765,7 @@ static int hmat_set_default_dram_perf(void)
        int rc;
        int nid, pxm;
        struct memory_target *target;
-       struct node_hmem_attrs *attrs;
+       struct access_coordinate *attrs;
 
        if (!default_dram_type)
                return -EIO;
@@ -775,7 +775,7 @@ static int hmat_set_default_dram_perf(void)
                target = find_mem_target(pxm);
                if (!target)
                        continue;
-               attrs = &target->hmem_attrs[1];
+               attrs = &target->coord[1];
                rc = mt_set_default_dram_perf(nid, attrs, "ACPI HMAT");
                if (rc)
                        return rc;
@@ -789,7 +789,7 @@ static int hmat_calculate_adistance(struct notifier_block *self,
 {
        static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
        struct memory_target *target;
-       struct node_hmem_attrs *perf;
+       struct access_coordinate *perf;
        int *adist = data;
        int pxm;
 
@@ -802,7 +802,7 @@ static int hmat_calculate_adistance(struct notifier_block *self,
        hmat_update_target_attrs(target, p_nodes, 1);
        mutex_unlock(&target_lock);
 
-       perf = &target->hmem_attrs[1];
+       perf = &target->coord[1];
 
        if (mt_perf_to_adistance(perf, adist))
                return NOTIFY_OK;

diff --git a/drivers/base/node.c b/drivers/base/node.c
index 493d533f8375560a1503167363b42480b4d2b897..cb2b6cc7f6e69fb7d03e960b68dc54e466af2e5a 100644 (file)
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -74,14 +74,14 @@ static BIN_ATTR_RO(cpulist, CPULIST_FILE_MAX_BYTES);
  * @dev:       Device for this memory access class
  * @list_node: List element in the node's access list
  * @access:    The access class rank
- * @hmem_attrs: Heterogeneous memory performance attributes
+ * @coord:     Heterogeneous memory performance coordinates
  */
 struct node_access_nodes {
        struct device           dev;
        struct list_head        list_node;
        unsigned int            access;
 #ifdef CONFIG_HMEM_REPORTING
-       struct node_hmem_attrs  hmem_attrs;
+       struct access_coordinate        coord;
 #endif
 };
 #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
@@ -167,7 +167,7 @@ static ssize_t property##_show(struct device *dev,                  \
                           char *buf)                                   \
 {                                                                      \
        return sysfs_emit(buf, "%u\n",                                  \
-                         to_access_nodes(dev)->hmem_attrs.property);   \
+                         to_access_nodes(dev)->coord.property);        \
 }                                                                      \
 static DEVICE_ATTR_RO(property)
 
@@ -187,10 +187,10 @@ static struct attribute *access_attrs[] = {
 /**
  * node_set_perf_attrs - Set the performance values for given access class
  * @nid: Node identifier to be set
- * @hmem_attrs: Heterogeneous memory performance attributes
+ * @coord: Heterogeneous memory performance coordinates
  * @access: The access class the for the given attributes
  */
-void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
+void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
                         unsigned int access)
 {
        struct node_access_nodes *c;
@@ -205,7 +205,7 @@ void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
        if (!c)
                return;
 
-       c->hmem_attrs = *hmem_attrs;
+       c->coord = *coord;
        for (i = 0; access_attrs[i] != NULL; i++) {
                if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
                                            "initiators")) {

diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h
index 1e39d27bee418c1a7c0a6a966bbc249056f008fd..69e78190008271a94ebdabb9d944612c58acb7e1 100644 (file)
--- a/include/linux/memory-tiers.h
+++ b/include/linux/memory-tiers.h
@@ -33,7 +33,7 @@ struct memory_dev_type {
        struct kref kref;
 };
 
-struct node_hmem_attrs;
+struct access_coordinate;
 
 #ifdef CONFIG_NUMA
 extern bool numa_demotion_enabled;
@@ -45,9 +45,9 @@ void clear_node_memory_type(int node, struct memory_dev_type *memtype);
 int register_mt_adistance_algorithm(struct notifier_block *nb);
 int unregister_mt_adistance_algorithm(struct notifier_block *nb);
 int mt_calc_adistance(int node, int *adist);
-int mt_set_default_dram_perf(int nid, struct node_hmem_attrs *perf,
+int mt_set_default_dram_perf(int nid, struct access_coordinate *perf,
                             const char *source);
-int mt_perf_to_adistance(struct node_hmem_attrs *perf, int *adist);
+int mt_perf_to_adistance(struct access_coordinate *perf, int *adist);
 #ifdef CONFIG_MIGRATION
 int next_demotion_node(int node);
 void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *targets);
@@ -126,13 +126,13 @@ static inline int mt_calc_adistance(int node, int *adist)
        return NOTIFY_DONE;
 }
 
-static inline int mt_set_default_dram_perf(int nid, struct node_hmem_attrs *perf,
+static inline int mt_set_default_dram_perf(int nid, struct access_coordinate *perf,
                                           const char *source)
 {
        return -EIO;
 }
 
-static inline int mt_perf_to_adistance(struct node_hmem_attrs *perf, int *adist)
+static inline int mt_perf_to_adistance(struct access_coordinate *perf, int *adist)
 {
        return -EIO;
 }

diff --git a/include/linux/node.h b/include/linux/node.h
index 427a5975cf405045ded741ed4c1b4b9eaca1ffec..25b66d705ee2ec754021d5ea2e2f1bce15ef7dbe 100644 (file)
--- a/include/linux/node.h
+++ b/include/linux/node.h
@@ -20,14 +20,14 @@
 #include <linux/list.h>
 
 /**
- * struct node_hmem_attrs - heterogeneous memory performance attributes
+ * struct access_coordinate - generic performance coordinates container
  *
  * @read_bandwidth:    Read bandwidth in MB/s
  * @write_bandwidth:   Write bandwidth in MB/s
  * @read_latency:      Read latency in nanoseconds
  * @write_latency:     Write latency in nanoseconds
  */
-struct node_hmem_attrs {
+struct access_coordinate {
        unsigned int read_bandwidth;
        unsigned int write_bandwidth;
        unsigned int read_latency;
@@ -65,7 +65,7 @@ struct node_cache_attrs {
 
 #ifdef CONFIG_HMEM_REPORTING
 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
-void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
+void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
                         unsigned access);
 #else
 static inline void node_add_cache(unsigned int nid,
@@ -74,7 +74,7 @@ static inline void node_add_cache(unsigned int nid,
 }
 
 static inline void node_set_perf_attrs(unsigned int nid,
-                                      struct node_hmem_attrs *hmem_attrs,
+                                      struct access_coordinate *coord,
                                       unsigned access)
 {
 }

diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c
index 8d5291add2bce6df6849165b725e73ab04dff557..5462d9e3c84c7d41af4e29f00c16cd00efb0ace3 100644 (file)
--- a/mm/memory-tiers.c
+++ b/mm/memory-tiers.c
@@ -109,7 +109,7 @@ static struct demotion_nodes *node_demotion __read_mostly;
 static BLOCKING_NOTIFIER_HEAD(mt_adistance_algorithms);
 
 static bool default_dram_perf_error;
-static struct node_hmem_attrs default_dram_perf;
+static struct access_coordinate default_dram_perf;
 static int default_dram_perf_ref_nid = NUMA_NO_NODE;
 static const char *default_dram_perf_ref_source;
 
@@ -601,15 +601,15 @@ void clear_node_memory_type(int node, struct memory_dev_type *memtype)
 }
 EXPORT_SYMBOL_GPL(clear_node_memory_type);
 
-static void dump_hmem_attrs(struct node_hmem_attrs *attrs, const char *prefix)
+static void dump_hmem_attrs(struct access_coordinate *coord, const char *prefix)
 {
        pr_info(
 "%sread_latency: %u, write_latency: %u, read_bandwidth: %u, write_bandwidth: %u\n",
-               prefix, attrs->read_latency, attrs->write_latency,
-               attrs->read_bandwidth, attrs->write_bandwidth);
+               prefix, coord->read_latency, coord->write_latency,
+               coord->read_bandwidth, coord->write_bandwidth);
 }
 
-int mt_set_default_dram_perf(int nid, struct node_hmem_attrs *perf,
+int mt_set_default_dram_perf(int nid, struct access_coordinate *perf,
                             const char *source)
 {
        int rc = 0;
@@ -666,7 +666,7 @@ out:
        return rc;
 }
 
-int mt_perf_to_adistance(struct node_hmem_attrs *perf, int *adist)
+int mt_perf_to_adistance(struct access_coordinate *perf, int *adist)
 {
        if (default_dram_perf_error)
                return -EIO;