diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index f0fea095d16a..8aa98f9bc723 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4414,12 +4414,13 @@ enum mc_target_type { MC_TARGET_NONE = 0, MC_TARGET_PAGE, MC_TARGET_SWAP, + MC_TARGET_DEVICE, }; static struct page *mc_handle_present_pte(struct vm_area_struct *vma, unsigned long addr, pte_t ptent) { - struct page *page = vm_normal_page(vma, addr, ptent); + struct page *page = _vm_normal_page(vma, addr, ptent, true); if (!page || !page_mapped(page)) return NULL; @@ -4436,7 +4437,7 @@ static struct page *mc_handle_present_pte(struct vm_area_struct *vma, return page; } -#ifdef CONFIG_SWAP +#if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE) static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, pte_t ptent, swp_entry_t *entry) { @@ -4445,6 +4446,23 @@ static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, if (!(mc.flags & MOVE_ANON) || non_swap_entry(ent)) return NULL; + + /* + * Handle MEMORY_DEVICE_PRIVATE which are ZONE_DEVICE page belonging to + * a device and because they are not accessible by CPU they are store + * as special swap entry in the CPU page table. + */ + if (is_device_private_entry(ent)) { + page = device_private_entry_to_page(ent); + /* + * MEMORY_DEVICE_PRIVATE means ZONE_DEVICE page and which have + * a refcount of 1 when free (unlike normal page) + */ + if (!page_ref_add_unless(page, 1, 1)) + return NULL; + return page; + } + /* * Because lookup_swap_cache() updates some statistics counter, * we call find_get_page() with swapper_space directly. @@ -4605,6 +4623,12 @@ out: * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a * target for charge migration. if @target is not NULL, the entry is stored * in target->ent. + * 3(MC_TARGET_DEVICE): like MC_TARGET_PAGE but page is MEMORY_DEVICE_PRIVATE + * (so ZONE_DEVICE page and thus not on the lru). For now we such page is + * charge like a regular page would be as for all intent and purposes it is + * just special memory taking the place of a regular page. + * + * See Documentations/vm/hmm.txt and include/linux/hmm.h * * Called with pte lock held. */ @@ -4633,6 +4657,8 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, */ if (page->mem_cgroup == mc.from) { ret = MC_TARGET_PAGE; + if (is_device_private_page(page)) + ret = MC_TARGET_DEVICE; if (target) target->page = page; } @@ -4700,6 +4726,11 @@ static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, ptl = pmd_trans_huge_lock(pmd, vma); if (ptl) { + /* + * Note their can not be MC_TARGET_DEVICE for now as we do not + * support transparent huge page with MEMORY_DEVICE_PUBLIC or + * MEMORY_DEVICE_PRIVATE but this might change. + */ if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) mc.precharge += HPAGE_PMD_NR; spin_unlock(ptl); @@ -4915,6 +4946,14 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, putback_lru_page(page); } put_page(page); + } else if (target_type == MC_TARGET_DEVICE) { + page = target.page; + if (!mem_cgroup_move_account(page, true, + mc.from, mc.to)) { + mc.precharge -= HPAGE_PMD_NR; + mc.moved_charge += HPAGE_PMD_NR; + } + put_page(page); } spin_unlock(ptl); return 0; @@ -4926,12 +4965,16 @@ retry: pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); for (; addr != end; addr += PAGE_SIZE) { pte_t ptent = *(pte++); + bool device = false; swp_entry_t ent; if (!mc.precharge) break; switch (get_mctgt_type(vma, addr, ptent, &target)) { + case MC_TARGET_DEVICE: + device = true; + /* fall through */ case MC_TARGET_PAGE: page = target.page; /* @@ -4942,7 +4985,7 @@ retry: */ if (PageTransCompound(page)) goto put; - if (isolate_lru_page(page)) + if (!device && isolate_lru_page(page)) goto put; if (!mem_cgroup_move_account(page, false, mc.from, mc.to)) { @@ -4950,7 +4993,8 @@ retry: /* we uncharge from mc.from later. */ mc.moved_charge++; } - putback_lru_page(page); + if (!device) + putback_lru_page(page); put: /* get_mctgt_type() gets the page */ put_page(page); break; |