On Thu, Jan 21, 2021 at 02:27:20PM +0200, Mike Rapoport wrote:
From: Mike Rapoport rppt@linux.ibm.com
Account memory consumed by secretmem to memcg. The accounting is updated when the memory is actually allocated and freed.
I think this is wrong. It fails to account subsequent allocators from the same PMD. If you want to track like this, you need separate pools per memcg.
I think you shouldn't try to track like this; better to just track on a per-page basis. After all, the page allocator doesn't track order-10 pages to the memcg that initially caused them to be split.
Signed-off-by: Mike Rapoport rppt@linux.ibm.com Acked-by: Roman Gushchin guro@fb.com Reviewed-by: Shakeel Butt shakeelb@google.com Cc: Alexander Viro viro@zeniv.linux.org.uk Cc: Andy Lutomirski luto@kernel.org Cc: Arnd Bergmann arnd@arndb.de Cc: Borislav Petkov bp@alien8.de Cc: Catalin Marinas catalin.marinas@arm.com Cc: Christopher Lameter cl@linux.com Cc: Dan Williams dan.j.williams@intel.com Cc: Dave Hansen dave.hansen@linux.intel.com Cc: David Hildenbrand david@redhat.com Cc: Elena Reshetova elena.reshetova@intel.com Cc: Hagen Paul Pfeifer hagen@jauu.net Cc: "H. Peter Anvin" hpa@zytor.com Cc: Ingo Molnar mingo@redhat.com Cc: James Bottomley jejb@linux.ibm.com Cc: "Kirill A. Shutemov" kirill@shutemov.name Cc: Mark Rutland mark.rutland@arm.com Cc: Matthew Wilcox willy@infradead.org Cc: Michael Kerrisk mtk.manpages@gmail.com Cc: Palmer Dabbelt palmer@dabbelt.com Cc: Palmer Dabbelt palmerdabbelt@google.com Cc: Paul Walmsley paul.walmsley@sifive.com Cc: Peter Zijlstra peterz@infradead.org Cc: Rick Edgecombe rick.p.edgecombe@intel.com Cc: Shuah Khan shuah@kernel.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Tycho Andersen tycho@tycho.ws Cc: Will Deacon will@kernel.org
mm/filemap.c | 3 ++- mm/secretmem.c | 36 +++++++++++++++++++++++++++++++++++- 2 files changed, 37 insertions(+), 2 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c index 2d0c6721879d..bb28dd6d9e22 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -42,6 +42,7 @@ #include <linux/psi.h> #include <linux/ramfs.h> #include <linux/page_idle.h> +#include <linux/secretmem.h> #include "internal.h" #define CREATE_TRACE_POINTS @@ -839,7 +840,7 @@ noinline int __add_to_page_cache_locked(struct page *page, page->mapping = mapping; page->index = offset;
- if (!huge) {
- if (!huge && !page_is_secretmem(page)) { error = mem_cgroup_charge(page, current->mm, gfp); if (error) goto error;
diff --git a/mm/secretmem.c b/mm/secretmem.c index 469211c7cc3a..05026460e2ee 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -18,6 +18,7 @@ #include <linux/memblock.h> #include <linux/pseudo_fs.h> #include <linux/secretmem.h> +#include <linux/memcontrol.h> #include <linux/set_memory.h> #include <linux/sched/signal.h> @@ -44,6 +45,32 @@ struct secretmem_ctx { static struct cma *secretmem_cma; +static int secretmem_account_pages(struct page *page, gfp_t gfp, int order) +{
- int err;
- err = memcg_kmem_charge_page(page, gfp, order);
- if (err)
return err;- /*
* seceremem caches are unreclaimable kernel allocations, so treat* them as unreclaimable slab memory for VM statistics purposes*/- mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE_B,
PAGE_SIZE << order);- return 0;
+}
+static void secretmem_unaccount_pages(struct page *page, int order) +{
- mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE_B,
-PAGE_SIZE << order);- memcg_kmem_uncharge_page(page, order);
+}
static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER); @@ -56,6 +83,10 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) if (!page) return -ENOMEM;
- err = secretmem_account_pages(page, gfp, PMD_PAGE_ORDER);
- if (err)
goto err_cma_release;- /*
- clear the data left from the prevoius user before dropping the
- pages from the direct map
@@ -65,7 +96,7 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) err = set_direct_map_invalid_noflush(page, nr_pages); if (err)
goto err_cma_release;
goto err_memcg_uncharge;addr = (unsigned long)page_address(page); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); @@ -83,6 +114,8 @@ 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_unaccount_pages(page, PMD_PAGE_ORDER);
err_cma_release: cma_release(secretmem_cma, page, nr_pages); return err; @@ -314,6 +347,7 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, int i; set_direct_map_default_noflush(page, nr_pages);
- secretmem_unaccount_pages(page, PMD_PAGE_ORDER);
for (i = 0; i < nr_pages; i++) clear_highpage(page + i); -- 2.28.0