mm: use leaf entries in debug pgtable + remove is_swap_pte()

Remove invocations of is_swap_pte() in mm/debug_vm_pgtable.c and use
softleaf_from_pte() and softleaf_is_swap() as necessary to replace this
usage.

We update the test code to use a 'true' swap entry throughout so we are
guaranteed this is not a non-swap entry, so all asserts continue to
operate correctly.

With this change in place, we no longer use is_swap_pte() anywhere, so
remove it.

Link: https://lkml.kernel.org/r/222f352e7a99191b4bdfa77e835f2fc0dd83fa72.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index 0a4b3f51ecf559ab6ac04a82d2ecdbd58b1f53ff..a66ac4f2105c55ab7f53a465e17692216862ef1c 100644 (file)
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -120,12 +120,6 @@ static inline unsigned long swp_offset_pfn(swp_entry_t entry)
        return swp_offset(entry) & SWP_PFN_MASK;
 }
 
-/* check whether a pte points to a swap entry */
-static inline int is_swap_pte(pte_t pte)
-{
-       return !pte_none(pte) && !pte_present(pte);
-}
-
 /*
  * Convert the arch-dependent pte representation of a swp_entry_t into an
  * arch-independent swp_entry_t.

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 055e0e025b42d366d6730f5ac919ed4d626b4b35..fff3118309598f64f1d1ccbfbc96f78fa2e904c6 100644 (file)
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -25,7 +25,7 @@
 #include <linux/random.h>
 #include <linux/spinlock.h>
 #include <linux/swap.h>
-#include <linux/swapops.h>
+#include <linux/leafops.h>
 #include <linux/start_kernel.h>
 #include <linux/sched/mm.h>
 #include <linux/io.h>
@@ -714,14 +714,16 @@ static void __init pte_soft_dirty_tests(struct pgtable_debug_args *args)
 static void __init pte_swap_soft_dirty_tests(struct pgtable_debug_args *args)
 {
        pte_t pte;
+       softleaf_t entry;
 
        if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY))
                return;
 
        pr_debug("Validating PTE swap soft dirty\n");
        pte = swp_entry_to_pte(args->swp_entry);
-       WARN_ON(!is_swap_pte(pte));
+       entry = softleaf_from_pte(pte);
 
+       WARN_ON(!softleaf_is_swap(entry));
        WARN_ON(!pte_swp_soft_dirty(pte_swp_mksoft_dirty(pte)));
        WARN_ON(pte_swp_soft_dirty(pte_swp_clear_soft_dirty(pte)));
 }
@@ -768,40 +770,47 @@ static void __init pmd_swap_soft_dirty_tests(struct pgtable_debug_args *args) {
 
 static void __init pte_swap_exclusive_tests(struct pgtable_debug_args *args)
 {
-       swp_entry_t entry, entry2;
+       swp_entry_t entry;
+       softleaf_t softleaf;
        pte_t pte;
 
        pr_debug("Validating PTE swap exclusive\n");
        entry = args->swp_entry;
 
        pte = swp_entry_to_pte(entry);
+       softleaf = softleaf_from_pte(pte);
+
        WARN_ON(pte_swp_exclusive(pte));
-       WARN_ON(!is_swap_pte(pte));
-       entry2 = pte_to_swp_entry(pte);
-       WARN_ON(memcmp(&entry, &entry2, sizeof(entry)));
+       WARN_ON(!softleaf_is_swap(softleaf));
+       WARN_ON(memcmp(&entry, &softleaf, sizeof(entry)));
 
        pte = pte_swp_mkexclusive(pte);
+       softleaf = softleaf_from_pte(pte);
+
        WARN_ON(!pte_swp_exclusive(pte));
-       WARN_ON(!is_swap_pte(pte));
+       WARN_ON(!softleaf_is_swap(softleaf));
        WARN_ON(pte_swp_soft_dirty(pte));
-       entry2 = pte_to_swp_entry(pte);
-       WARN_ON(memcmp(&entry, &entry2, sizeof(entry)));
+       WARN_ON(memcmp(&entry, &softleaf, sizeof(entry)));
 
        pte = pte_swp_clear_exclusive(pte);
+       softleaf = softleaf_from_pte(pte);
+
        WARN_ON(pte_swp_exclusive(pte));
-       WARN_ON(!is_swap_pte(pte));
-       entry2 = pte_to_swp_entry(pte);
-       WARN_ON(memcmp(&entry, &entry2, sizeof(entry)));
+       WARN_ON(!softleaf_is_swap(softleaf));
+       WARN_ON(memcmp(&entry, &softleaf, sizeof(entry)));
 }
 
 static void __init pte_swap_tests(struct pgtable_debug_args *args)
 {
        swp_entry_t arch_entry;
+       softleaf_t entry;
        pte_t pte1, pte2;
 
        pr_debug("Validating PTE swap\n");
        pte1 = swp_entry_to_pte(args->swp_entry);
-       WARN_ON(!is_swap_pte(pte1));
+       entry = softleaf_from_pte(pte1);
+
+       WARN_ON(!softleaf_is_swap(entry));
 
        arch_entry = __pte_to_swp_entry(pte1);
        pte2 = __swp_entry_to_pte(arch_entry);
@@ -1218,8 +1227,8 @@ static int __init init_args(struct pgtable_debug_args *args)
 
        /* See generic_max_swapfile_size(): probe the maximum offset */
        max_swap_offset = swp_offset(pte_to_swp_entry(swp_entry_to_pte(swp_entry(0, ~0UL))));
-       /* Create a swp entry with all possible bits set */
-       args->swp_entry = swp_entry((1 << MAX_SWAPFILES_SHIFT) - 1, max_swap_offset);
+       /* Create a swp entry with all possible bits set while still being swap. */
+       args->swp_entry = swp_entry(MAX_SWAPFILES - 1, max_swap_offset);
 
        /*
         * Allocate (huge) pages because some of the tests need to access