[PATCH v8 6/9] secretmem: add memcg accounting
From: Mike Rapoport <rppt@kernel.org>
Date: 2020-11-10 15:16:06
Also in:
linux-arch, linux-arm-kernel, linux-fsdevel, linux-kselftest, linux-mm, linux-riscv, lkml, nvdimm
Subsystem:
memory management, memory management - secretmem, page cache, the rest · Maintainers:
Andrew Morton, Mike Rapoport, Matthew Wilcox, Jan Kara, Linus Torvalds
From: Mike Rapoport <redacted> Account memory consumed by secretmem to memcg. The accounting is updated when the memory is actually allocated and freed. Signed-off-by: Mike Rapoport <redacted> --- mm/filemap.c | 2 +- mm/secretmem.c | 42 +++++++++++++++++++++++++++++++++++++++++- 2 files changed, 42 insertions(+), 2 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 249cf489f5df..11387a077373 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c@@ -844,7 +844,7 @@ static noinline int __add_to_page_cache_locked(struct page *page, page->mapping = mapping; page->index = offset; - if (!huge) { + if (!huge && !page->memcg_data) { error = mem_cgroup_charge(page, current->mm, gfp); if (error) goto error;
diff --git a/mm/secretmem.c b/mm/secretmem.c
index 1aa2b7cffe0d..1eb7667016fa 100644
--- a/mm/secretmem.c
+++ b/mm/secretmem.c@@ -17,6 +17,7 @@ #include <linux/syscalls.h> #include <linux/memblock.h> #include <linux/pseudo_fs.h> +#include <linux/memcontrol.h> #include <linux/set_memory.h> #include <linux/sched/signal.h>
@@ -49,6 +50,38 @@ struct secretmem_ctx { static struct cma *secretmem_cma; +static int secretmem_memcg_charge(struct page *page, gfp_t gfp, int order) +{ + unsigned long nr_pages = (1 << order); + int i, err; + + err = memcg_kmem_charge_page(page, gfp, order); + if (err) + return err; + + for (i = 1; i < nr_pages; i++) { + struct page *p = page + i; + + p->memcg_data = page->memcg_data; + } + + return 0; +} + +static void secretmem_memcg_uncharge(struct page *page, int order) +{ + unsigned long nr_pages = (1 << order); + int i; + + for (i = 1; i < nr_pages; i++) { + struct page *p = page + i; + + p->memcg_data = 0; + } + + memcg_kmem_uncharge_page(page, PMD_PAGE_ORDER); +} + static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER);
@@ -61,10 +94,14 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) if (!page) return -ENOMEM; - err = set_direct_map_invalid_noflush(page, nr_pages); + err = secretmem_memcg_charge(page, gfp, PMD_PAGE_ORDER); if (err) goto err_cma_release; + err = set_direct_map_invalid_noflush(page, nr_pages); + if (err) + goto err_memcg_uncharge; + addr = (unsigned long)page_address(page); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); if (err)
@@ -81,6 +118,8 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) * won't fail */ set_direct_map_default_noflush(page, nr_pages); +err_memcg_uncharge: + secretmem_memcg_uncharge(page, PMD_PAGE_ORDER); err_cma_release: cma_release(secretmem_cma, page, nr_pages); return err;
@@ -310,6 +349,7 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, int i; set_direct_map_default_noflush(page, nr_pages); + secretmem_memcg_uncharge(page, PMD_PAGE_ORDER); for (i = 0; i < nr_pages; i++) clear_highpage(page + i);
--
2.28.0