Modularize the collapse action of khugepaged collapse selftests by
introducing a struct collapse_context which specifies how to collapse a
given memory range and the expected semantics of the collapse. This
can be reused later to test other collapse contexts.
Signed-off-by: Zach O'Keefe <zokeefe@xxxxxxxxxx>
---
tools/testing/selftests/vm/khugepaged.c | 257 +++++++++++-------------
1 file changed, 116 insertions(+), 141 deletions(-)
diff --git a/tools/testing/selftests/vm/khugepaged.c b/tools/testing/selftests/vm/khugepaged.c
index 155120b67a16..c59d832fee96 100644
--- a/tools/testing/selftests/vm/khugepaged.c
+++ b/tools/testing/selftests/vm/khugepaged.c
@@ -23,6 +23,12 @@ static int hpage_pmd_nr;
#define THP_SYSFS "/sys/kernel/mm/transparent_hugepage/"
#define PID_SMAPS "/proc/self/smaps"
+struct collapse_context {
+ const char *name;
+ void (*collapse)(const char *msg, char *p, bool expect);
+ bool enforce_pte_scan_limits;
+};
+
enum thp_enabled {
THP_ALWAYS,
THP_MADVISE,
@@ -528,53 +534,39 @@ static void alloc_at_fault(void)
munmap(p, hpage_pmd_size);
}
-static void collapse_full(void)
+static void collapse_full(struct collapse_context *context)
{
void *p;
p = alloc_mapping();
fill_memory(p, 0, hpage_pmd_size);
- if (wait_for_scan("Collapse fully populated PTE table", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse fully populated PTE table", p, true);
validate_memory(p, 0, hpage_pmd_size);
munmap(p, hpage_pmd_size);
}
-static void collapse_empty(void)
+static void collapse_empty(struct collapse_context *context)
{
void *p;
p = alloc_mapping();
- if (wait_for_scan("Do not collapse empty PTE table", p))
- fail("Timeout");
- else if (check_huge(p))
- fail("Fail");
- else
- success("OK");
+ context->collapse("Do not collapse empty PTE table", p, false);
munmap(p, hpage_pmd_size);
}
-static void collapse_single_pte_entry(void)
+static void collapse_single_pte_entry(struct collapse_context *context)
{
void *p;
p = alloc_mapping();
fill_memory(p, 0, page_size);
- if (wait_for_scan("Collapse PTE table with single PTE entry present", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse PTE table with single PTE entry present", p,
+ true);
validate_memory(p, 0, page_size);
munmap(p, hpage_pmd_size);
}
-static void collapse_max_ptes_none(void)
+static void collapse_max_ptes_none(struct collapse_context *context)
{
int max_ptes_none = hpage_pmd_nr / 2;
struct settings settings = default_settings;
@@ -586,28 +578,23 @@ static void collapse_max_ptes_none(void)
p = alloc_mapping();
fill_memory(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
- if (wait_for_scan("Do not collapse with max_ptes_none exceeded", p))
- fail("Timeout");
- else if (check_huge(p))
- fail("Fail");
- else
- success("OK");
+ context->collapse("Maybe collapse with max_ptes_none exceeded", p,
+ !context->enforce_pte_scan_limits);
validate_memory(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
- fill_memory(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
- if (wait_for_scan("Collapse with max_ptes_none PTEs empty", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
- validate_memory(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
+ if (context->enforce_pte_scan_limits) {
+ fill_memory(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
+ context->collapse("Collapse with max_ptes_none PTEs empty", p,
+ true);
+ validate_memory(p, 0,
+ (hpage_pmd_nr - max_ptes_none) * page_size);
+ }
munmap(p, hpage_pmd_size);
write_settings(&default_settings);
}
-static void collapse_swapin_single_pte(void)
+static void collapse_swapin_single_pte(struct collapse_context *context)
{
void *p;
p = alloc_mapping();
@@ -625,18 +612,14 @@ static void collapse_swapin_single_pte(void)
goto out;
}
- if (wait_for_scan("Collapse with swapping in single PTE entry", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse with swapping in single PTE entry",
+ p, true);
validate_memory(p, 0, hpage_pmd_size);
out:
munmap(p, hpage_pmd_size);
}
-static void collapse_max_ptes_swap(void)
+static void collapse_max_ptes_swap(struct collapse_context *context)
{
int max_ptes_swap = read_num("khugepaged/max_ptes_swap");
void *p;
@@ -656,39 +639,34 @@ static void collapse_max_ptes_swap(void)
goto out;
}
- if (wait_for_scan("Do not collapse with max_ptes_swap exceeded", p))
- fail("Timeout");
- else if (check_huge(p))
- fail("Fail");
- else
- success("OK");
+ context->collapse("Maybe collapse with max_ptes_swap exceeded",
+ p, !context->enforce_pte_scan_limits);
validate_memory(p, 0, hpage_pmd_size);
- fill_memory(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)) {
- perror("madvise(MADV_PAGEOUT)");
- exit(EXIT_FAILURE);
- }
- if (check_swap(p, max_ptes_swap * page_size)) {
- success("OK");
- } else {
- fail("Fail");
- goto out;
- }
+ if (context->enforce_pte_scan_limits) {
+ fill_memory(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)) {
+ perror("madvise(MADV_PAGEOUT)");
+ exit(EXIT_FAILURE);
+ }
+ if (check_swap(p, max_ptes_swap * page_size)) {
+ success("OK");
+ } else {
+ fail("Fail");
+ goto out;
+ }
- if (wait_for_scan("Collapse with max_ptes_swap pages swapped out", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
- validate_memory(p, 0, hpage_pmd_size);
+ context->collapse("Collapse with max_ptes_swap pages swapped out",
+ p, true);
+ validate_memory(p, 0, hpage_pmd_size);
+ }
out:
munmap(p, hpage_pmd_size);
}
-static void collapse_single_pte_entry_compound(void)
+static void collapse_single_pte_entry_compound(struct collapse_context *context)
{
void *p;
@@ -710,17 +688,13 @@ static void collapse_single_pte_entry_compound(void)
else
fail("Fail");
- if (wait_for_scan("Collapse PTE table with single PTE mapping compound page", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse PTE table with single PTE mapping compound page",
+ p, true);
validate_memory(p, 0, page_size);
munmap(p, hpage_pmd_size);
}
-static void collapse_full_of_compound(void)
+static void collapse_full_of_compound(struct collapse_context *context)
{
void *p;
@@ -742,17 +716,12 @@ static void collapse_full_of_compound(void)
else
fail("Fail");
- if (wait_for_scan("Collapse PTE table full of compound pages", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse PTE table full of compound pages", p, true);
validate_memory(p, 0, hpage_pmd_size);
munmap(p, hpage_pmd_size);
}
-static void collapse_compound_extreme(void)
+static void collapse_compound_extreme(struct collapse_context *context)
{
void *p;
int i;
@@ -798,18 +767,14 @@ static void collapse_compound_extreme(void)
else
fail("Fail");
- if (wait_for_scan("Collapse PTE table full of different compound pages", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse PTE table full of different compound pages",
+ p, true);
validate_memory(p, 0, hpage_pmd_size);
munmap(p, hpage_pmd_size);
}
-static void collapse_fork(void)
+static void collapse_fork(struct collapse_context *context)
{
int wstatus;
void *p;
@@ -835,13 +800,8 @@ static void collapse_fork(void)
fail("Fail");
fill_memory(p, page_size, 2 * page_size);
-
- if (wait_for_scan("Collapse PTE table with single page shared with parent process", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse PTE table with single page shared with parent process",
+ p, true);
validate_memory(p, 0, page_size);
munmap(p, hpage_pmd_size);
@@ -860,7 +820,7 @@ static void collapse_fork(void)
munmap(p, hpage_pmd_size);
}
-static void collapse_fork_compound(void)
+static void collapse_fork_compound(struct collapse_context *context)
{
int wstatus;
void *p;
@@ -896,14 +856,10 @@ static void collapse_fork_compound(void)
fill_memory(p, 0, page_size);
write_num("khugepaged/max_ptes_shared", hpage_pmd_nr - 1);
- if (wait_for_scan("Collapse PTE table full of compound pages in child", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Collapse PTE table full of compound pages in child",
+ p, true);
write_num("khugepaged/max_ptes_shared",
- default_settings.khugepaged.max_ptes_shared);
+ default_settings.khugepaged.max_ptes_shared);
validate_memory(p, 0, hpage_pmd_size);
munmap(p, hpage_pmd_size);
@@ -922,7 +878,7 @@ static void collapse_fork_compound(void)
munmap(p, hpage_pmd_size);
}
-static void collapse_max_ptes_shared()
+static void collapse_max_ptes_shared(struct collapse_context *context)
{
int max_ptes_shared = read_num("khugepaged/max_ptes_shared");
int wstatus;
@@ -957,28 +913,22 @@ static void collapse_max_ptes_shared()
else
fail("Fail");
- if (wait_for_scan("Do not collapse with max_ptes_shared exceeded", p))
- fail("Timeout");
- else if (!check_huge(p))
- success("OK");
- else
- fail("Fail");
-
- 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) * page_size);
- if (!check_huge(p))
- success("OK");
- else
- fail("Fail");
-
-
- if (wait_for_scan("Collapse with max_ptes_shared PTEs shared", p))
- fail("Timeout");
- else if (check_huge(p))
- success("OK");
- else
- fail("Fail");
+ context->collapse("Maybe collapse with max_ptes_shared exceeded",
+ p, !context->enforce_pte_scan_limits);
+
+ if (context->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) *
+ page_size);
+ if (!check_huge(p))
+ success("OK");
+ else
+ fail("Fail");
+
+ context->collapse("Collapse with max_ptes_shared PTEs shared",
+ p, true);
+ }
validate_memory(p, 0, hpage_pmd_size);
munmap(p, hpage_pmd_size);
@@ -997,8 +947,27 @@ static void collapse_max_ptes_shared()
munmap(p, hpage_pmd_size);
}
+static void khugepaged_collapse(const char *msg, char *p, bool expect)
+{
+ if (wait_for_scan(msg, p))
+ fail("Timeout");
+ else if (check_huge(p) == expect)
+ success("OK");
+ else
+ fail("Fail");
+}
+
int main(void)
{
+ struct collapse_context contexts[] = {
+ {
+ .name = "khugepaged",
+ .collapse = &khugepaged_collapse,
+ .enforce_pte_scan_limits = true,
+ },
+ };
+ int i;
+
setbuf(stdout, NULL);
page_size = getpagesize();
@@ -1014,18 +983,24 @@ int main(void)
adjust_settings();
alloc_at_fault();
- collapse_full();
- collapse_empty();
- collapse_single_pte_entry();
- collapse_max_ptes_none();
- collapse_swapin_single_pte();
- collapse_max_ptes_swap();
- collapse_single_pte_entry_compound();
- collapse_full_of_compound();
- collapse_compound_extreme();
- collapse_fork();
- collapse_fork_compound();
- collapse_max_ptes_shared();
+
+ for (i = 0; i < sizeof(contexts) / sizeof(contexts[0]); ++i) {
+ struct collapse_context *c = &contexts[i];
+
+ printf("\n*** Testing context: %s ***\n", c->name);
+ 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);
+ }
restore_settings(0);
}
--
2.35.1.1178.g4f1659d476-goog
