selftests/vm: modularize thp collapse memory operations
authorZach O'Keefe <zokeefe@google.com>
Thu, 22 Sep 2022 22:40:42 +0000 (15:40 -0700)
committerAndrew Morton <akpm@linux-foundation.org>
Mon, 3 Oct 2022 21:03:34 +0000 (14:03 -0700)
Modularize operations to setup, cleanup, fault, and check for huge pages,
for a given memory type.  This allows reusing existing tests with
additional memory types by defining new memory operations.  Following
patches will add file and shmem memory types.

Link: https://lkml.kernel.org/r/20220907144521.3115321-7-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220922224046.1143204-7-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Houghton <jthoughton@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
tools/testing/selftests/vm/khugepaged.c

index 235a64b..06ea6f1 100644 (file)
@@ -29,8 +29,16 @@ static int hpage_pmd_nr;
 #define THP_SYSFS "/sys/kernel/mm/transparent_hugepage/"
 #define PID_SMAPS "/proc/self/smaps"
 
+struct mem_ops {
+       void *(*setup_area)(int nr_hpages);
+       void (*cleanup_area)(void *p, unsigned long size);
+       void (*fault)(void *p, unsigned long start, unsigned long end);
+       bool (*check_huge)(void *addr, int nr_hpages);
+};
+
 struct collapse_context {
-       void (*collapse)(const char *msg, char *p, int nr_hpages, bool expect);
+       void (*collapse)(const char *msg, char *p, int nr_hpages,
+                        struct mem_ops *ops, bool expect);
        bool enforce_pte_scan_limits;
 };
 
@@ -354,11 +362,6 @@ static void save_settings(void)
        signal(SIGQUIT, restore_settings);
 }
 
-static bool check_huge(void *addr, int nr_hpages)
-{
-       return check_huge_anon(addr, nr_hpages, hpage_pmd_size);
-}
-
 #define MAX_LINE_LENGTH 500
 static bool check_swap(void *addr, unsigned long size)
 {
@@ -452,18 +455,33 @@ retry:
  * Returns pmd-mapped hugepage in VMA marked VM_HUGEPAGE, filled with
  * validate_memory()'able contents.
  */
-static void *alloc_hpage(void)
+static void *alloc_hpage(struct mem_ops *ops)
 {
-       void *p;
+       void *p = ops->setup_area(1);
 
-       p = alloc_mapping(1);
+       ops->fault(p, 0, hpage_pmd_size);
+
+       /*
+        * VMA should be neither VM_HUGEPAGE nor VM_NOHUGEPAGE.
+        * The latter is ineligible for collapse by MADV_COLLAPSE
+        * while the former might cause MADV_COLLAPSE to race with
+        * khugepaged on low-load system (like a test machine), which
+        * would cause MADV_COLLAPSE to fail with EAGAIN.
+        */
        printf("Allocate huge page...");
-       madvise(p, hpage_pmd_size, MADV_HUGEPAGE);
-       fill_memory(p, 0, hpage_pmd_size);
-       if (check_huge(p, 1))
-               success("OK");
-       else
-               fail("Fail");
+       if (madvise_collapse_retry(p, hpage_pmd_size)) {
+               perror("madvise(MADV_COLLAPSE)");
+               exit(EXIT_FAILURE);
+       }
+       if (!ops->check_huge(p, 1)) {
+               perror("madvise(MADV_COLLAPSE)");
+               exit(EXIT_FAILURE);
+       }
+       if (madvise(p, hpage_pmd_size, MADV_HUGEPAGE)) {
+               perror("madvise(MADV_HUGEPAGE)");
+               exit(EXIT_FAILURE);
+       }
+       success("OK");
        return p;
 }
 
@@ -480,18 +498,40 @@ static void validate_memory(int *p, unsigned long start, unsigned long end)
        }
 }
 
-static void madvise_collapse(const char *msg, char *p, int nr_hpages,
-                            bool expect)
+static void *anon_setup_area(int nr_hpages)
+{
+       return alloc_mapping(nr_hpages);
+}
+
+static void anon_cleanup_area(void *p, unsigned long size)
+{
+       munmap(p, size);
+}
+
+static void anon_fault(void *p, unsigned long start, unsigned long end)
+{
+       fill_memory(p, start, end);
+}
+
+static bool anon_check_huge(void *addr, int nr_hpages)
+{
+       return check_huge_anon(addr, nr_hpages, hpage_pmd_size);
+}
+
+static struct mem_ops anon_ops = {
+       .setup_area = &anon_setup_area,
+       .cleanup_area = &anon_cleanup_area,
+       .fault = &anon_fault,
+       .check_huge = &anon_check_huge,
+};
+
+static void __madvise_collapse(const char *msg, char *p, int nr_hpages,
+                              struct mem_ops *ops, bool expect)
 {
        int ret;
        struct settings settings = *current_settings();
 
        printf("%s...", msg);
-       /* Sanity check */
-       if (!check_huge(p, 0)) {
-               printf("Unexpected huge page\n");
-               exit(EXIT_FAILURE);
-       }
 
        /*
         * Prevent khugepaged interference and tests that MADV_COLLAPSE
@@ -505,7 +545,7 @@ static void madvise_collapse(const char *msg, char *p, int nr_hpages,
        ret = madvise_collapse_retry(p, nr_hpages * hpage_pmd_size);
        if (((bool)ret) == expect)
                fail("Fail: Bad return value");
-       else if (check_huge(p, nr_hpages) != expect)
+       else if (!ops->check_huge(p, expect ? nr_hpages : 0))
                fail("Fail: check_huge()");
        else
                success("OK");
@@ -513,14 +553,26 @@ static void madvise_collapse(const char *msg, char *p, int nr_hpages,
        pop_settings();
 }
 
+static void madvise_collapse(const char *msg, char *p, int nr_hpages,
+                            struct mem_ops *ops, bool expect)
+{
+       /* Sanity check */
+       if (!ops->check_huge(p, 0)) {
+               printf("Unexpected huge page\n");
+               exit(EXIT_FAILURE);
+       }
+       __madvise_collapse(msg, p, nr_hpages, ops, expect);
+}
+
 #define TICK 500000
-static bool wait_for_scan(const char *msg, char *p, int nr_hpages)
+static bool wait_for_scan(const char *msg, char *p, int nr_hpages,
+                         struct mem_ops *ops)
 {
        int full_scans;
        int timeout = 6; /* 3 seconds */
 
        /* Sanity check */
-       if (!check_huge(p, 0)) {
+       if (!ops->check_huge(p, 0)) {
                printf("Unexpected huge page\n");
                exit(EXIT_FAILURE);
        }
@@ -532,7 +584,7 @@ static bool wait_for_scan(const char *msg, char *p, int nr_hpages)
 
        printf("%s...", msg);
        while (timeout--) {
-               if (check_huge(p, nr_hpages))
+               if (ops->check_huge(p, nr_hpages))
                        break;
                if (read_num("khugepaged/full_scans") >= full_scans)
                        break;
@@ -546,19 +598,20 @@ static bool wait_for_scan(const char *msg, char *p, int nr_hpages)
 }
 
 static void khugepaged_collapse(const char *msg, char *p, int nr_hpages,
-                               bool expect)
+                               struct mem_ops *ops, bool expect)
 {
-       if (wait_for_scan(msg, p, nr_hpages)) {
+       if (wait_for_scan(msg, p, nr_hpages, ops)) {
                if (expect)
                        fail("Timeout");
                else
                        success("OK");
                return;
-       } else if (check_huge(p, nr_hpages) == expect) {
+       }
+
+       if (ops->check_huge(p, expect ? nr_hpages : 0))
                success("OK");
-       } else {
+       else
                fail("Fail");
-       }
 }
 
 static void alloc_at_fault(void)
@@ -572,7 +625,7 @@ static void alloc_at_fault(void)
        p = alloc_mapping(1);
        *p = 1;
        printf("Allocate huge page on fault...");
-       if (check_huge(p, 1))
+       if (check_huge_anon(p, 1, hpage_pmd_size))
                success("OK");
        else
                fail("Fail");
@@ -581,49 +634,48 @@ static void alloc_at_fault(void)
 
        madvise(p, page_size, MADV_DONTNEED);
        printf("Split huge PMD on MADV_DONTNEED...");
-       if (check_huge(p, 0))
+       if (check_huge_anon(p, 0, hpage_pmd_size))
                success("OK");
        else
                fail("Fail");
        munmap(p, hpage_pmd_size);
 }
 
-static void collapse_full(struct collapse_context *c)
+static void collapse_full(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
        int nr_hpages = 4;
        unsigned long size = nr_hpages * hpage_pmd_size;
 
-       p = alloc_mapping(nr_hpages);
-       fill_memory(p, 0, size);
+       p = ops->setup_area(nr_hpages);
+       ops->fault(p, 0, size);
        c->collapse("Collapse multiple fully populated PTE table", p, nr_hpages,
-                   true);
+                   ops, true);
        validate_memory(p, 0, size);
-       munmap(p, size);
+       ops->cleanup_area(p, size);
 }
 
-static void collapse_empty(struct collapse_context *c)
+static void collapse_empty(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
 
-       p = alloc_mapping(1);
-       c->collapse("Do not collapse empty PTE table", p, 1, false);
-       munmap(p, hpage_pmd_size);
+       p = ops->setup_area(1);
+       c->collapse("Do not collapse empty PTE table", p, 1, ops, false);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_single_pte_entry(struct collapse_context *c)
+static void collapse_single_pte_entry(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
 
-       p = alloc_mapping(1);
-       fill_memory(p, 0, page_size);
+       p = ops->setup_area(1);
+       ops->fault(p, 0, page_size);
        c->collapse("Collapse PTE table with single PTE entry present", p,
-                   1, true);
-       validate_memory(p, 0, page_size);
-       munmap(p, hpage_pmd_size);
+                   1, ops, true);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_max_ptes_none(struct collapse_context *c)
+static void collapse_max_ptes_none(struct collapse_context *c, struct mem_ops *ops)
 {
        int max_ptes_none = hpage_pmd_nr / 2;
        struct settings settings = *current_settings();
@@ -632,30 +684,30 @@ static void collapse_max_ptes_none(struct collapse_context *c)
        settings.khugepaged.max_ptes_none = max_ptes_none;
        push_settings(&settings);
 
-       p = alloc_mapping(1);
+       p = ops->setup_area(1);
 
-       fill_memory(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
+       ops->fault(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
        c->collapse("Maybe collapse with max_ptes_none exceeded", p, 1,
-                   !c->enforce_pte_scan_limits);
+                   ops, !c->enforce_pte_scan_limits);
        validate_memory(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
 
        if (c->enforce_pte_scan_limits) {
-               fill_memory(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
-               c->collapse("Collapse with max_ptes_none PTEs empty", p, 1,
+               ops->fault(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
+               c->collapse("Collapse with max_ptes_none PTEs empty", p, 1, ops,
                            true);
                validate_memory(p, 0,
                                (hpage_pmd_nr - max_ptes_none) * page_size);
        }
-
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
        pop_settings();
 }
 
-static void collapse_swapin_single_pte(struct collapse_context *c)
+static void collapse_swapin_single_pte(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
-       p = alloc_mapping(1);
-       fill_memory(p, 0, hpage_pmd_size);
+
+       p = ops->setup_area(1);
+       ops->fault(p, 0, hpage_pmd_size);
 
        printf("Swapout one page...");
        if (madvise(p, page_size, MADV_PAGEOUT)) {
@@ -669,20 +721,21 @@ static void collapse_swapin_single_pte(struct collapse_context *c)
                goto out;
        }
 
-       c->collapse("Collapse with swapping in single PTE entry", p, 1, true);
+       c->collapse("Collapse with swapping in single PTE entry", p, 1, ops,
+                   true);
        validate_memory(p, 0, hpage_pmd_size);
 out:
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_max_ptes_swap(struct collapse_context *c)
+static void collapse_max_ptes_swap(struct collapse_context *c, struct mem_ops *ops)
 {
        int max_ptes_swap = read_num("khugepaged/max_ptes_swap");
        void *p;
 
-       p = alloc_mapping(1);
+       p = ops->setup_area(1);
+       ops->fault(p, 0, hpage_pmd_size);
 
-       fill_memory(p, 0, hpage_pmd_size);
        printf("Swapout %d of %d pages...", max_ptes_swap + 1, hpage_pmd_nr);
        if (madvise(p, (max_ptes_swap + 1) * page_size, MADV_PAGEOUT)) {
                perror("madvise(MADV_PAGEOUT)");
@@ -695,12 +748,12 @@ static void collapse_max_ptes_swap(struct collapse_context *c)
                goto out;
        }
 
-       c->collapse("Maybe collapse with max_ptes_swap exceeded", p, 1,
+       c->collapse("Maybe collapse with max_ptes_swap exceeded", p, 1, ops,
                    !c->enforce_pte_scan_limits);
        validate_memory(p, 0, hpage_pmd_size);
 
        if (c->enforce_pte_scan_limits) {
-               fill_memory(p, 0, hpage_pmd_size);
+               ops->fault(p, 0, hpage_pmd_size);
                printf("Swapout %d of %d pages...", max_ptes_swap,
                       hpage_pmd_nr);
                if (madvise(p, max_ptes_swap * page_size, MADV_PAGEOUT)) {
@@ -715,63 +768,65 @@ static void collapse_max_ptes_swap(struct collapse_context *c)
                }
 
                c->collapse("Collapse with max_ptes_swap pages swapped out", p,
-                           1, true);
+                           1, ops, true);
                validate_memory(p, 0, hpage_pmd_size);
        }
 out:
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_single_pte_entry_compound(struct collapse_context *c)
+static void collapse_single_pte_entry_compound(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
 
-       p = alloc_hpage();
+       p = alloc_hpage(ops);
+
        madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
        printf("Split huge page leaving single PTE mapping compound page...");
        madvise(p + page_size, hpage_pmd_size - page_size, MADV_DONTNEED);
-       if (check_huge(p, 0))
+       if (ops->check_huge(p, 0))
                success("OK");
        else
                fail("Fail");
 
        c->collapse("Collapse PTE table with single PTE mapping compound page",
-                   p, 1, true);
+                   p, 1, ops, true);
        validate_memory(p, 0, page_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_full_of_compound(struct collapse_context *c)
+static void collapse_full_of_compound(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
 
-       p = alloc_hpage();
+       p = alloc_hpage(ops);
        printf("Split huge page leaving single PTE page table full of compound pages...");
        madvise(p, page_size, MADV_NOHUGEPAGE);
        madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
-       if (check_huge(p, 0))
+       if (ops->check_huge(p, 0))
                success("OK");
        else
                fail("Fail");
 
-       c->collapse("Collapse PTE table full of compound pages", p, 1, true);
+       c->collapse("Collapse PTE table full of compound pages", p, 1, ops,
+                   true);
        validate_memory(p, 0, hpage_pmd_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_compound_extreme(struct collapse_context *c)
+static void collapse_compound_extreme(struct collapse_context *c, struct mem_ops *ops)
 {
        void *p;
        int i;
 
-       p = alloc_mapping(1);
+       p = ops->setup_area(1);
        for (i = 0; i < hpage_pmd_nr; i++) {
                printf("\rConstruct PTE page table full of different PTE-mapped compound pages %3d/%d...",
                                i + 1, hpage_pmd_nr);
 
                madvise(BASE_ADDR, hpage_pmd_size, MADV_HUGEPAGE);
-               fill_memory(BASE_ADDR, 0, hpage_pmd_size);
-               if (!check_huge(BASE_ADDR, 1)) {
+               ops->fault(BASE_ADDR, 0, hpage_pmd_size);
+               if (!ops->check_huge(BASE_ADDR, 1)) {
                        printf("Failed to allocate huge page\n");
                        exit(EXIT_FAILURE);
                }
@@ -798,30 +853,30 @@ static void collapse_compound_extreme(struct collapse_context *c)
                }
        }
 
-       munmap(BASE_ADDR, hpage_pmd_size);
-       fill_memory(p, 0, hpage_pmd_size);
-       if (check_huge(p, 0))
+       ops->cleanup_area(BASE_ADDR, hpage_pmd_size);
+       ops->fault(p, 0, hpage_pmd_size);
+       if (!ops->check_huge(p, 1))
                success("OK");
        else
                fail("Fail");
 
        c->collapse("Collapse PTE table full of different compound pages", p, 1,
-                   true);
+                   ops, true);
 
        validate_memory(p, 0, hpage_pmd_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_fork(struct collapse_context *c)
+static void collapse_fork(struct collapse_context *c, struct mem_ops *ops)
 {
        int wstatus;
        void *p;
 
-       p = alloc_mapping(1);
+       p = ops->setup_area(1);
 
        printf("Allocate small page...");
-       fill_memory(p, 0, page_size);
-       if (check_huge(p, 0))
+       ops->fault(p, 0, page_size);
+       if (ops->check_huge(p, 0))
                success("OK");
        else
                fail("Fail");
@@ -832,17 +887,17 @@ static void collapse_fork(struct collapse_context *c)
                skip_settings_restore = true;
                exit_status = 0;
 
-               if (check_huge(p, 0))
+               if (ops->check_huge(p, 0))
                        success("OK");
                else
                        fail("Fail");
 
-               fill_memory(p, page_size, 2 * page_size);
+               ops->fault(p, page_size, 2 * page_size);
                c->collapse("Collapse PTE table with single page shared with parent process",
-                           p, 1, true);
+                           p, 1, ops, true);
 
                validate_memory(p, 0, page_size);
-               munmap(p, hpage_pmd_size);
+               ops->cleanup_area(p, hpage_pmd_size);
                exit(exit_status);
        }
 
@@ -850,27 +905,27 @@ static void collapse_fork(struct collapse_context *c)
        exit_status += WEXITSTATUS(wstatus);
 
        printf("Check if parent still has small page...");
-       if (check_huge(p, 0))
+       if (ops->check_huge(p, 0))
                success("OK");
        else
                fail("Fail");
        validate_memory(p, 0, page_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_fork_compound(struct collapse_context *c)
+static void collapse_fork_compound(struct collapse_context *c, struct mem_ops *ops)
 {
        int wstatus;
        void *p;
 
-       p = alloc_hpage();
+       p = alloc_hpage(ops);
        printf("Share huge page over fork()...");
        if (!fork()) {
                /* Do not touch settings on child exit */
                skip_settings_restore = true;
                exit_status = 0;
 
-               if (check_huge(p, 1))
+               if (ops->check_huge(p, 1))
                        success("OK");
                else
                        fail("Fail");
@@ -878,20 +933,20 @@ static void collapse_fork_compound(struct collapse_context *c)
                printf("Split huge page PMD in child process...");
                madvise(p, page_size, MADV_NOHUGEPAGE);
                madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
-               if (check_huge(p, 0))
+               if (ops->check_huge(p, 0))
                        success("OK");
                else
                        fail("Fail");
-               fill_memory(p, 0, page_size);
+               ops->fault(p, 0, page_size);
 
                write_num("khugepaged/max_ptes_shared", hpage_pmd_nr - 1);
                c->collapse("Collapse PTE table full of compound pages in child",
-                           p, 1, true);
+                           p, 1, ops, true);
                write_num("khugepaged/max_ptes_shared",
                          current_settings()->khugepaged.max_ptes_shared);
 
                validate_memory(p, 0, hpage_pmd_size);
-               munmap(p, hpage_pmd_size);
+               ops->cleanup_area(p, hpage_pmd_size);
                exit(exit_status);
        }
 
@@ -899,59 +954,59 @@ static void collapse_fork_compound(struct collapse_context *c)
        exit_status += WEXITSTATUS(wstatus);
 
        printf("Check if parent still has huge page...");
-       if (check_huge(p, 1))
+       if (ops->check_huge(p, 1))
                success("OK");
        else
                fail("Fail");
        validate_memory(p, 0, hpage_pmd_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void collapse_max_ptes_shared(struct collapse_context *c)
+static void collapse_max_ptes_shared(struct collapse_context *c, struct mem_ops *ops)
 {
        int max_ptes_shared = read_num("khugepaged/max_ptes_shared");
        int wstatus;
        void *p;
 
-       p = alloc_hpage();
+       p = alloc_hpage(ops);
        printf("Share huge page over fork()...");
        if (!fork()) {
                /* Do not touch settings on child exit */
                skip_settings_restore = true;
                exit_status = 0;
 
-               if (check_huge(p, 1))
+               if (ops->check_huge(p, 1))
                        success("OK");
                else
                        fail("Fail");
 
                printf("Trigger CoW on page %d of %d...",
                                hpage_pmd_nr - max_ptes_shared - 1, hpage_pmd_nr);
-               fill_memory(p, 0, (hpage_pmd_nr - max_ptes_shared - 1) * page_size);
-               if (check_huge(p, 0))
+               ops->fault(p, 0, (hpage_pmd_nr - max_ptes_shared - 1) * page_size);
+               if (ops->check_huge(p, 0))
                        success("OK");
                else
                        fail("Fail");
 
                c->collapse("Maybe collapse with max_ptes_shared exceeded", p,
-                           1, !c->enforce_pte_scan_limits);
+                           1, ops, !c->enforce_pte_scan_limits);
 
                if (c->enforce_pte_scan_limits) {
                        printf("Trigger CoW on page %d of %d...",
                               hpage_pmd_nr - max_ptes_shared, hpage_pmd_nr);
-                       fill_memory(p, 0, (hpage_pmd_nr - max_ptes_shared) *
+                       ops->fault(p, 0, (hpage_pmd_nr - max_ptes_shared) *
                                    page_size);
-                       if (check_huge(p, 0))
+                       if (ops->check_huge(p, 0))
                                success("OK");
                        else
                                fail("Fail");
 
                        c->collapse("Collapse with max_ptes_shared PTEs shared",
-                                   p, 1,  true);
+                                   p, 1, ops, true);
                }
 
                validate_memory(p, 0, hpage_pmd_size);
-               munmap(p, hpage_pmd_size);
+               ops->cleanup_area(p, hpage_pmd_size);
                exit(exit_status);
        }
 
@@ -959,42 +1014,28 @@ static void collapse_max_ptes_shared(struct collapse_context *c)
        exit_status += WEXITSTATUS(wstatus);
 
        printf("Check if parent still has huge page...");
-       if (check_huge(p, 1))
+       if (ops->check_huge(p, 1))
                success("OK");
        else
                fail("Fail");
        validate_memory(p, 0, hpage_pmd_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
-static void madvise_collapse_existing_thps(void)
+static void madvise_collapse_existing_thps(struct collapse_context *c,
+                                          struct mem_ops *ops)
 {
        void *p;
-       int err;
 
-       p = alloc_mapping(1);
-       fill_memory(p, 0, hpage_pmd_size);
+       p = ops->setup_area(1);
+       ops->fault(p, 0, hpage_pmd_size);
+       c->collapse("Collapse fully populated PTE table...", p, 1, ops, true);
+       validate_memory(p, 0, hpage_pmd_size);
 
-       printf("Collapse fully populated PTE table...");
-       /*
-        * Note that we don't set MADV_HUGEPAGE here, which
-        * also tests that VM_HUGEPAGE isn't required for
-        * MADV_COLLAPSE in "madvise" mode.
-        */
-       err = madvise(p, hpage_pmd_size, MADV_COLLAPSE);
-       if (err == 0 && check_huge(p, 1)) {
-               success("OK");
-               printf("Re-collapse PMD-mapped hugepage");
-               err = madvise(p, hpage_pmd_size, MADV_COLLAPSE);
-               if (err == 0 && check_huge(p, 1))
-                       success("OK");
-               else
-                       fail("Fail");
-       } else {
-               fail("Fail");
-       }
+       /* c->collapse() will find a hugepage and complain - call directly. */
+       __madvise_collapse("Re-collapse PMD-mapped hugepage", p, 1, ops, true);
        validate_memory(p, 0, hpage_pmd_size);
-       munmap(p, hpage_pmd_size);
+       ops->cleanup_area(p, hpage_pmd_size);
 }
 
 int main(int argc, const char **argv)
@@ -1034,37 +1075,37 @@ int main(int argc, const char **argv)
                c.collapse = &khugepaged_collapse;
                c.enforce_pte_scan_limits = true;
 
-               collapse_full(&c);
-               collapse_empty(&c);
-               collapse_single_pte_entry(&c);
-               collapse_max_ptes_none(&c);
-               collapse_swapin_single_pte(&c);
-               collapse_max_ptes_swap(&c);
-               collapse_single_pte_entry_compound(&c);
-               collapse_full_of_compound(&c);
-               collapse_compound_extreme(&c);
-               collapse_fork(&c);
-               collapse_fork_compound(&c);
-               collapse_max_ptes_shared(&c);
+               collapse_full(&c, &anon_ops);
+               collapse_empty(&c, &anon_ops);
+               collapse_single_pte_entry(&c, &anon_ops);
+               collapse_max_ptes_none(&c, &anon_ops);
+               collapse_swapin_single_pte(&c, &anon_ops);
+               collapse_max_ptes_swap(&c, &anon_ops);
+               collapse_single_pte_entry_compound(&c, &anon_ops);
+               collapse_full_of_compound(&c, &anon_ops);
+               collapse_compound_extreme(&c, &anon_ops);
+               collapse_fork(&c, &anon_ops);
+               collapse_fork_compound(&c, &anon_ops);
+               collapse_max_ptes_shared(&c, &anon_ops);
        }
        if (!strcmp(tests, "madvise") || !strcmp(tests, "all")) {
                printf("\n*** Testing context: madvise ***\n");
                c.collapse = &madvise_collapse;
                c.enforce_pte_scan_limits = false;
 
-               collapse_full(&c);
-               collapse_empty(&c);
-               collapse_single_pte_entry(&c);
-               collapse_max_ptes_none(&c);
-               collapse_swapin_single_pte(&c);
-               collapse_max_ptes_swap(&c);
-               collapse_single_pte_entry_compound(&c);
-               collapse_full_of_compound(&c);
-               collapse_compound_extreme(&c);
-               collapse_fork(&c);
-               collapse_fork_compound(&c);
-               collapse_max_ptes_shared(&c);
-               madvise_collapse_existing_thps();
+               collapse_full(&c, &anon_ops);
+               collapse_empty(&c, &anon_ops);
+               collapse_single_pte_entry(&c, &anon_ops);
+               collapse_max_ptes_none(&c, &anon_ops);
+               collapse_swapin_single_pte(&c, &anon_ops);
+               collapse_max_ptes_swap(&c, &anon_ops);
+               collapse_single_pte_entry_compound(&c, &anon_ops);
+               collapse_full_of_compound(&c, &anon_ops);
+               collapse_compound_extreme(&c, &anon_ops);
+               collapse_fork(&c, &anon_ops);
+               collapse_fork_compound(&c, &anon_ops);
+               collapse_max_ptes_shared(&c, &anon_ops);
+               madvise_collapse_existing_thps(&c, &anon_ops);
        }
 
        restore_settings(0);