From: SeongJae Park Date: Thu, 28 Aug 2025 17:12:32 +0000 (-0700) Subject: mm/damon/core: add damon_ctx->addr_unit X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=64ca8b8301de50f6a407550d3a12a15c306b0200;p=users%2Fjedix%2Flinux-maple.git mm/damon/core: add damon_ctx->addr_unit Patch series "mm/damon: support ARM32 with LPAE", v3. Previously, DAMON's physical address space monitoring only supported memory ranges below 4GB on LPAE-enabled systems. This was due to the use of 'unsigned long' in 'struct damon_addr_range', which is 32-bit on ARM32 even with LPAE enabled[1]. To add DAMON support for ARM32 with LPAE enabled, a new core layer parameter called 'addr_unit' was introduced[2]. Operations set layer can translate a core layer address to the real address by multiplying the parameter value to the core layer address. Support of the parameter is up to each operations layer implementation, though. For example, operations set implementations for virtual address space can simply ignore the parameter. Add the support on paddr, which is the DAMON operations set implementation for the physical address space, as we have a clear use case for that. This patch (of 11): In some cases, some of the real address that handled by the underlying operations set cannot be handled by DAMON since it uses only 'unsinged long' as the address type. Using DAMON for physical address space monitoring of 32 bit ARM devices with large physical address extension (LPAE) is one example[1]. Add a parameter name 'addr_unit' to core layer to help such cases. DAMON core API callers can set it as the scale factor that will be used by the operations set for translating the core layer's addresses to the real address by multiplying the parameter value to the core layer address. Support of the parameter is up to each operations set layer. The support from the physical address space operations set (paddr) will be added with following commits. Link: https://lkml.kernel.org/r/20250828171242.59810-1-sj@kernel.org Link: https://lkml.kernel.org/r/20250828171242.59810-2-sj@kernel.org Link: https://lore.kernel.org/20250408075553.959388-1-zuoze1@huawei.com [1] Link: https://lore.kernel.org/all/20250416042551.158131-1-sj@kernel.org/ [2] Signed-off-by: SeongJae Park Signed-off-by: Quanmin Yan Reviewed-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Kefeng Wang Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: ze zuo Signed-off-by: Andrew Morton --- diff --git a/include/linux/damon.h b/include/linux/damon.h index 71721df9385f..43d997aad254 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -748,7 +748,7 @@ struct damon_attrs { * Accesses to other fields must be protected by themselves. * * @ops: Set of monitoring operations for given use cases. - * + * @addr_unit: Scale factor for core to ops address conversion. * @adaptive_targets: Head of monitoring targets (&damon_target) list. * @schemes: Head of schemes (&damos) list. */ @@ -790,6 +790,7 @@ struct damon_ctx { struct mutex kdamond_lock; struct damon_operations ops; + unsigned long addr_unit; struct list_head adaptive_targets; struct list_head schemes; diff --git a/mm/damon/core.c b/mm/damon/core.c index c7838ff0c081..9776891cbfa4 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -544,6 +544,8 @@ struct damon_ctx *damon_new_ctx(void) ctx->attrs.min_nr_regions = 10; ctx->attrs.max_nr_regions = 1000; + ctx->addr_unit = 1; + INIT_LIST_HEAD(&ctx->adaptive_targets); INIT_LIST_HEAD(&ctx->schemes); @@ -1245,6 +1247,7 @@ int damon_commit_ctx(struct damon_ctx *dst, struct damon_ctx *src) return err; } dst->ops = src->ops; + dst->addr_unit = src->addr_unit; return 0; }