On 12.06.25 20:13, Bijan Tabatabai wrote:
From: Bijan Tabatabai <bijantabatab@xxxxxxxxxx> This patch adds the DAMOS_INTERLEAVE action. It interleaves pages inside of a given region according to the weights in the iw_table. To reuse existing interleaving code, the target nid for a folio is determined by calling policy_nodemask, therefore only folios belonging to processes using the MPOL_WEIGHTED_INTERLEAVE policy will have their pages migrated. Below is an example of its usage where pages are initially interleaved at a 1:1 ratio and then changed to be interleaved at a 2:1 ratio. The alloc_data program simply allocates 1GB of data then sleeps. $ cd /sys/kernel/mm/damon/admin/kdamonds/0 $ sudo cat ./contexts/0/schemes/0/action interleave $ echo 1 | sudo tee /sys/kernel/mm/mempolicy/weighted_interleave/node0 $ echo 1 | sudo tee /sys/kernel/mm/mempolicy/weighted_interleave/node1 $ numactl -w 0,1 ~/alloc_data 1G & $ numastat -c -p alloc_data Per-node process memory usage (in MBs) for PID 18473 (alloc_data) Node 0 Node 1 Total ------ ------ ----- Huge 0 0 0 Heap 0 0 0 Stack 0 0 0 Private 514 514 1027 ------- ------ ------ ----- Total 514 514 1028 $ echo 2 | sudo tee /sys/kernel/mm/mempolicy/weighted_interleave/node0 $ numastat -c -p alloc_data Per-node process memory usage (in MBs) for PID 18473 (alloc_data) Node 0 Node 1 Total ------ ------ ----- Huge 0 0 0 Heap 0 0 0 Stack 0 0 0 Private 684 343 1027 ------- ------ ------ ----- Total 684 343 1027 Signed-off-by: Bijan Tabatabai <bijantabatab@xxxxxxxxxx> --- Documentation/mm/damon/design.rst | 2 + include/linux/damon.h | 2 + mm/damon/paddr.c | 112 ++++++++++++++++++++++++++++++ mm/damon/sysfs-schemes.c | 1 + 4 files changed, 117 insertions(+) diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst index ddc50db3afa4..c50d2105cea0 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -455,6 +455,8 @@ that supports each action are as below. Supported by ``paddr`` operations set. - ``migrate_cold``: Migrate the regions prioritizing colder regions. Supported by ``paddr`` operations set. + - ``interleave``: Interleave the regions according to the weighted interleave weights. + Supported by ``paddr`` operations set. - ``stat``: Do nothing but count the statistics. Supported by all operations sets.diff --git a/include/linux/damon.h b/include/linux/damon.hindex a4011726cb3b..81d26a203337 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -117,6 +117,7 @@ struct damon_target { * @DAMOS_LRU_DEPRIO: Deprioritize the region on its LRU lists. * @DAMOS_MIGRATE_HOT: Migrate the regions prioritizing warmer regions. * @DAMOS_MIGRATE_COLD: Migrate the regions prioritizing colder regions. + * @DAMOS_INTERLEAVE: Interleave the regions by the weighted interleave ratio * @DAMOS_STAT: Do nothing but count the stat. * @NR_DAMOS_ACTIONS: Total number of DAMOS actions * @@ -136,6 +137,7 @@ enum damos_action { DAMOS_LRU_DEPRIO, DAMOS_MIGRATE_HOT, DAMOS_MIGRATE_COLD, + DAMOS_INTERLEAVE, DAMOS_STAT, /* Do nothing but only record the stat */ NR_DAMOS_ACTIONS, }; diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c index 4102a8c5f992..e989464635cd 100644 --- a/mm/damon/paddr.c +++ b/mm/damon/paddr.c @@ -535,6 +535,114 @@ static unsigned long damon_pa_migrate(struct damon_region *r, struct damos *s, return applied * PAGE_SIZE; }+#if defined(CONFIG_MEMCG) && defined(CONFIG_NUMA)+struct damos_interleave_private { + struct list_head *folio_migration_list; + bool putback_lru; +}; + +static bool damon_pa_interleave_rmap(struct folio *folio, struct vm_area_struct *vma, + unsigned long addr, void *arg) +{ + struct mempolicy *pol; + struct task_struct *task; + pgoff_t ilx; + int target_nid; + struct damos_interleave_private *priv = arg; + + task = rcu_dereference(vma->vm_mm->owner); + if (!task) + return true; + + pol = get_task_policy(task); + if (!pol) + return true;
Why is this not using get_vma_policy(), which will fallback to the task policy in case there is no per-vma policy>
-- Cheers, David / dhildenb
