| Message ID | 20230927095002.10245-2-ravis.opensrc@micron.com |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: mempolicy: Multi-tier interleaving | expand |
On Wed, 27 Sep 2023 15:20:01 +0530 Ravi Jonnalagadda <ravis.opensrc@micron.com> wrote: > From: Srinivasulu Thanneeru <sthanneeru@micron.com> > > Allocating pages across tiers is accomplished by provisioning > interleave weights for each tier, with the distribution based on > these weight values. > By default, all tiers will have a weight of 1, which means > default standard page allocation. By default all nodes within > tier will have weight of 1. > > Signed-off-by: Srinivasulu Thanneeru <sthanneeru@micron.com> > Co-authored-by: Ravi Jonnalagadda <ravis.opensrc@micron.com> ABI docs? Documentation/ABI/testing/sysfs-kernel-mm-memory-tiers A few trivial comments inline. > --- > include/linux/memory-tiers.h | 2 ++ > mm/memory-tiers.c | 46 +++++++++++++++++++++++++++++++++++- > 2 files changed, 47 insertions(+), 1 deletion(-) > > diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h > index 437441cdf78f..c62d286749d0 100644 > --- a/include/linux/memory-tiers.h > +++ b/include/linux/memory-tiers.h > @@ -19,6 +19,8 @@ > */ > #define MEMTIER_ADISTANCE_DRAM ((4 * MEMTIER_CHUNK_SIZE) + (MEMTIER_CHUNK_SIZE >> 1)) > > +#define MAX_TIER_INTERLEAVE_WEIGHT 100 > + > struct memory_tier; > struct memory_dev_type { > /* list of memory types that are part of same tier as this type */ > diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c > index 37a4f59d9585..7e06c9e0fa41 100644 > --- a/mm/memory-tiers.c > +++ b/mm/memory-tiers.c > @@ -13,6 +13,11 @@ struct memory_tier { > struct list_head list; > /* list of all memory types part of this tier */ > struct list_head memory_types; > + /* > + * By default all tiers will have weight as 1, which means they > + * follow default standard allocation. > + */ > + unsigned short interleave_weight; If you are going to use fixed size, keep it going. u16 (u8 as per below comment probably makes more sense) > /* > * start value of abstract distance. memory tier maps > * an abstract distance range, > @@ -145,8 +150,45 @@ static ssize_t nodelist_show(struct device *dev, > } > static DEVICE_ATTR_RO(nodelist); > > +static ssize_t interleave_weight_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + int ret; > + struct memory_tier *tier = to_memory_tier(dev); > + > + mutex_lock(&memory_tier_lock); > + ret = sysfs_emit(buf, "%u\n", tier->interleave_weight); > + mutex_unlock(&memory_tier_lock); For this one guard(mutex)(&memory_tier_lock); return sysfs_emit()... would perhaps be slightly nicer (see below) > + > + return ret; > +} > + > +static ssize_t interleave_weight_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t size) > +{ > + unsigned short value; > + int ret; > + struct memory_tier *tier = to_memory_tier(dev); > + > + ret = kstrtou16(buf, 0, &value); Why u16? Max is 100. I'd not mind if you just put it in an unsigned int, but seems odd to chose a specific size and pick one that is twice as big as needed! > + > + if (ret) > + return ret; > + if (value > MAX_TIER_INTERLEAVE_WEIGHT) > + return -EINVAL; > + > + mutex_lock(&memory_tier_lock); You could play with the new cleanup.h toys though it doesn't save a lot here. scoped_guard(mutex)(&memory_tier_lock) tier->interleave_weight = value; > + tier->interleave_weight = value; > + mutex_unlock(&memory_tier_lock); > + > + return size; > +} > +static DEVICE_ATTR_RW(interleave_weight); > + > static struct attribute *memtier_dev_attrs[] = { > &dev_attr_nodelist.attr, > + &dev_attr_interleave_weight.attr, > NULL > }; > > @@ -489,8 +531,10 @@ static struct memory_tier *set_node_memory_tier(int node) > memtype = node_memory_types[node].memtype; > node_set(node, memtype->nodes); > memtier = find_create_memory_tier(memtype); > - if (!IS_ERR(memtier)) > + if (!IS_ERR(memtier)) { > rcu_assign_pointer(pgdat->memtier, memtier); > + memtier->interleave_weight = 1; > + } > return memtier; > } >
diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h index 437441cdf78f..c62d286749d0 100644 --- a/include/linux/memory-tiers.h +++ b/include/linux/memory-tiers.h @@ -19,6 +19,8 @@ */ #define MEMTIER_ADISTANCE_DRAM ((4 * MEMTIER_CHUNK_SIZE) + (MEMTIER_CHUNK_SIZE >> 1)) +#define MAX_TIER_INTERLEAVE_WEIGHT 100 + struct memory_tier; struct memory_dev_type { /* list of memory types that are part of same tier as this type */ diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c index 37a4f59d9585..7e06c9e0fa41 100644 --- a/mm/memory-tiers.c +++ b/mm/memory-tiers.c @@ -13,6 +13,11 @@ struct memory_tier { struct list_head list; /* list of all memory types part of this tier */ struct list_head memory_types; + /* + * By default all tiers will have weight as 1, which means they + * follow default standard allocation. + */ + unsigned short interleave_weight; /* * start value of abstract distance. memory tier maps * an abstract distance range, @@ -145,8 +150,45 @@ static ssize_t nodelist_show(struct device *dev, } static DEVICE_ATTR_RO(nodelist); +static ssize_t interleave_weight_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + struct memory_tier *tier = to_memory_tier(dev); + + mutex_lock(&memory_tier_lock); + ret = sysfs_emit(buf, "%u\n", tier->interleave_weight); + mutex_unlock(&memory_tier_lock); + + return ret; +} + +static ssize_t interleave_weight_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + unsigned short value; + int ret; + struct memory_tier *tier = to_memory_tier(dev); + + ret = kstrtou16(buf, 0, &value); + + if (ret) + return ret; + if (value > MAX_TIER_INTERLEAVE_WEIGHT) + return -EINVAL; + + mutex_lock(&memory_tier_lock); + tier->interleave_weight = value; + mutex_unlock(&memory_tier_lock); + + return size; +} +static DEVICE_ATTR_RW(interleave_weight); + static struct attribute *memtier_dev_attrs[] = { &dev_attr_nodelist.attr, + &dev_attr_interleave_weight.attr, NULL }; @@ -489,8 +531,10 @@ static struct memory_tier *set_node_memory_tier(int node) memtype = node_memory_types[node].memtype; node_set(node, memtype->nodes); memtier = find_create_memory_tier(memtype); - if (!IS_ERR(memtier)) + if (!IS_ERR(memtier)) { rcu_assign_pointer(pgdat->memtier, memtier); + memtier->interleave_weight = 1; + } return memtier; }