diff options
| -rw-r--r-- | include/linux/damon.h | 10 | ||||
| -rw-r--r-- | mm/damon/Kconfig | 8 | ||||
| -rw-r--r-- | mm/damon/Makefile | 1 | ||||
| -rw-r--r-- | mm/damon/paddr.c | 224 |
4 files changed, 243 insertions, 0 deletions
diff --git a/include/linux/damon.h b/include/linux/damon.h index f301bb53381c..715dadd21f7c 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -351,4 +351,14 @@ void damon_va_set_primitives(struct damon_ctx *ctx); #endif /* CONFIG_DAMON_VADDR */ +#ifdef CONFIG_DAMON_PADDR + +/* Monitoring primitives for the physical memory address space */ +void damon_pa_prepare_access_checks(struct damon_ctx *ctx); +unsigned int damon_pa_check_accesses(struct damon_ctx *ctx); +bool damon_pa_target_valid(void *t); +void damon_pa_set_primitives(struct damon_ctx *ctx); + +#endif /* CONFIG_DAMON_PADDR */ + #endif /* _DAMON_H */ diff --git a/mm/damon/Kconfig b/mm/damon/Kconfig index ba8898c7eb8e..2a5923be631e 100644 --- a/mm/damon/Kconfig +++ b/mm/damon/Kconfig @@ -32,6 +32,14 @@ config DAMON_VADDR This builds the default data access monitoring primitives for DAMON that work for virtual address spaces. +config DAMON_PADDR + bool "Data access monitoring primitives for the physical address space" + depends on DAMON && MMU + select PAGE_IDLE_FLAG + help + This builds the default data access monitoring primitives for DAMON + that works for the physical address space. + config DAMON_VADDR_KUNIT_TEST bool "Test for DAMON primitives" if !KUNIT_ALL_TESTS depends on DAMON_VADDR && KUNIT=y diff --git a/mm/damon/Makefile b/mm/damon/Makefile index 99b1bfe01ff5..8d9b0df79702 100644 --- a/mm/damon/Makefile +++ b/mm/damon/Makefile @@ -2,4 +2,5 @@ obj-$(CONFIG_DAMON) := core.o obj-$(CONFIG_DAMON_VADDR) += prmtv-common.o vaddr.o +obj-$(CONFIG_DAMON_PADDR) += prmtv-common.o paddr.o obj-$(CONFIG_DAMON_DBGFS) += dbgfs.o diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c new file mode 100644 index 000000000000..d7a2ecd09ed0 --- /dev/null +++ b/mm/damon/paddr.c @@ -0,0 +1,224 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON Primitives for The Physical Address Space + * + * Author: SeongJae Park <sj@kernel.org> + */ + +#define pr_fmt(fmt) "damon-pa: " fmt + +#include <linux/mmu_notifier.h> +#include <linux/page_idle.h> +#include <linux/pagemap.h> +#include <linux/rmap.h> + +#include "prmtv-common.h" + +static bool __damon_pa_mkold(struct page *page, struct vm_area_struct *vma, + unsigned long addr, void *arg) +{ + struct page_vma_mapped_walk pvmw = { + .page = page, + .vma = vma, + .address = addr, + }; + + while (page_vma_mapped_walk(&pvmw)) { + addr = pvmw.address; + if (pvmw.pte) + damon_ptep_mkold(pvmw.pte, vma->vm_mm, addr); + else + damon_pmdp_mkold(pvmw.pmd, vma->vm_mm, addr); + } + return true; +} + +static void damon_pa_mkold(unsigned long paddr) +{ + struct page *page = damon_get_page(PHYS_PFN(paddr)); + struct rmap_walk_control rwc = { + .rmap_one = __damon_pa_mkold, + .anon_lock = page_lock_anon_vma_read, + }; + bool need_lock; + + if (!page) + return; + + if (!page_mapped(page) || !page_rmapping(page)) { + set_page_idle(page); + goto out; + } + + need_lock = !PageAnon(page) || PageKsm(page); + if (need_lock && !trylock_page(page)) + goto out; + + rmap_walk(page, &rwc); + + if (need_lock) + unlock_page(page); + +out: + put_page(page); +} + +static void __damon_pa_prepare_access_check(struct damon_ctx *ctx, + struct damon_region *r) +{ + r->sampling_addr = damon_rand(r->ar.start, r->ar.end); + + damon_pa_mkold(r->sampling_addr); +} + +void damon_pa_prepare_access_checks(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct damon_region *r; + + damon_for_each_target(t, ctx) { + damon_for_each_region(r, t) + __damon_pa_prepare_access_check(ctx, r); + } +} + +struct damon_pa_access_chk_result { + unsigned long page_sz; + bool accessed; +}; + +static bool __damon_pa_young(struct page *page, struct vm_area_struct *vma, + unsigned long addr, void *arg) +{ + struct damon_pa_access_chk_result *result = arg; + struct page_vma_mapped_walk pvmw = { + .page = page, + .vma = vma, + .address = addr, + }; + + result->accessed = false; + result->page_sz = PAGE_SIZE; + while (page_vma_mapped_walk(&pvmw)) { + addr = pvmw.address; + if (pvmw.pte) { + result->accessed = pte_young(*pvmw.pte) || + !page_is_idle(page) || + mmu_notifier_test_young(vma->vm_mm, addr); + } else { +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + result->accessed = pmd_young(*pvmw.pmd) || + !page_is_idle(page) || + mmu_notifier_test_young(vma->vm_mm, addr); + result->page_sz = ((1UL) << HPAGE_PMD_SHIFT); +#else + WARN_ON_ONCE(1); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ + } + if (result->accessed) { + page_vma_mapped_walk_done(&pvmw); + break; + } + } + + /* If accessed, stop walking */ + return !result->accessed; +} + +static bool damon_pa_young(unsigned long paddr, unsigned long *page_sz) +{ + struct page *page = damon_get_page(PHYS_PFN(paddr)); + struct damon_pa_access_chk_result result = { + .page_sz = PAGE_SIZE, + .accessed = false, + }; + struct rmap_walk_control rwc = { + .arg = &result, + .rmap_one = __damon_pa_young, + .anon_lock = page_lock_anon_vma_read, + }; + bool need_lock; + + if (!page) + return false; + + if (!page_mapped(page) || !page_rmapping(page)) { + if (page_is_idle(page)) + result.accessed = false; + else + result.accessed = true; + put_page(page); + goto out; + } + + need_lock = !PageAnon(page) || PageKsm(page); + if (need_lock && !trylock_page(page)) { + put_page(page); + return NULL; + } + + rmap_walk(page, &rwc); + + if (need_lock) + unlock_page(page); + put_page(page); + +out: + *page_sz = result.page_sz; + return result.accessed; +} + +static void __damon_pa_check_access(struct damon_ctx *ctx, + struct damon_region *r) +{ + static unsigned long last_addr; + static unsigned long last_page_sz = PAGE_SIZE; + static bool last_accessed; + + /* If the region is in the last checked page, reuse the result */ + if (ALIGN_DOWN(last_addr, last_page_sz) == + ALIGN_DOWN(r->sampling_addr, last_page_sz)) { + if (last_accessed) + r->nr_accesses++; + return; + } + + last_accessed = damon_pa_young(r->sampling_addr, &last_page_sz); + if (last_accessed) + r->nr_accesses++; + + last_addr = r->sampling_addr; +} + +unsigned int damon_pa_check_accesses(struct damon_ctx *ctx) +{ + struct damon_target *t; + struct damon_region *r; + unsigned int max_nr_accesses = 0; + + damon_for_each_target(t, ctx) { + damon_for_each_region(r, t) { + __damon_pa_check_access(ctx, r); + max_nr_accesses = max(r->nr_accesses, max_nr_accesses); + } + } + + return max_nr_accesses; +} + +bool damon_pa_target_valid(void *t) +{ + return true; +} + +void damon_pa_set_primitives(struct damon_ctx *ctx) +{ + ctx->primitive.init = NULL; + ctx->primitive.update = NULL; + ctx->primitive.prepare_access_checks = damon_pa_prepare_access_checks; + ctx->primitive.check_accesses = damon_pa_check_accesses; + ctx->primitive.reset_aggregated = NULL; + ctx->primitive.target_valid = damon_pa_target_valid; + ctx->primitive.cleanup = NULL; + ctx->primitive.apply_scheme = NULL; +} |