Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
mm/damon/vaddr: do not split regions for min_nr_regions
The previous commit made DAMON core split regions at the beginning for
min_nr_regions. The virtual address space operation set (vaddr) does
similar work on its own, for a case user delegates entire initial
monitoring regions setup to vaddr. It is unnecessary now, as DAMON core
will do similar work for any case. Remove the duplicated work in vaddr.
Also, remove a helper function that was being used only for the work, and
the test code of the helper function.
Link: https://lkml.kernel.org/r/20260228222831.7232-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
authored by
SeongJae Park
and committed by
Andrew Morton
442d87c7
b1029f29
+2
-144
-76
mm/damon/tests/vaddr-kunit.h
-76
mm/damon/tests/vaddr-kunit.h
···
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new_three_regions, expected, ARRAY_SIZE(expected));
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}
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-
static void damon_test_split_evenly_fail(struct kunit *test,
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-
unsigned long start, unsigned long end, unsigned int nr_pieces)
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-
{
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struct damon_target *t = damon_new_target();
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struct damon_region *r;
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-
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if (!t)
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kunit_skip(test, "target alloc fail");
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-
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r = damon_new_region(start, end);
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if (!r) {
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damon_free_target(t);
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kunit_skip(test, "region alloc fail");
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-
}
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-
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damon_add_region(r, t);
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-
KUNIT_EXPECT_EQ(test,
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damon_va_evenly_split_region(t, r, nr_pieces), -EINVAL);
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KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u);
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-
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-
damon_for_each_region(r, t) {
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KUNIT_EXPECT_EQ(test, r->ar.start, start);
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KUNIT_EXPECT_EQ(test, r->ar.end, end);
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}
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damon_free_target(t);
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}
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static void damon_test_split_evenly_succ(struct kunit *test,
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unsigned long start, unsigned long end, unsigned int nr_pieces)
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{
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struct damon_target *t = damon_new_target();
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struct damon_region *r;
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unsigned long expected_width = (end - start) / nr_pieces;
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unsigned long i = 0;
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-
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if (!t)
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kunit_skip(test, "target alloc fail");
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r = damon_new_region(start, end);
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if (!r) {
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damon_free_target(t);
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kunit_skip(test, "region alloc fail");
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}
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damon_add_region(r, t);
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KUNIT_EXPECT_EQ(test,
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damon_va_evenly_split_region(t, r, nr_pieces), 0);
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KUNIT_EXPECT_EQ(test, damon_nr_regions(t), nr_pieces);
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-
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damon_for_each_region(r, t) {
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-
if (i == nr_pieces - 1) {
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KUNIT_EXPECT_EQ(test,
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r->ar.start, start + i * expected_width);
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KUNIT_EXPECT_EQ(test, r->ar.end, end);
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break;
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}
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-
KUNIT_EXPECT_EQ(test,
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r->ar.start, start + i++ * expected_width);
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KUNIT_EXPECT_EQ(test, r->ar.end, start + i * expected_width);
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}
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damon_free_target(t);
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-
}
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-
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static void damon_test_split_evenly(struct kunit *test)
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{
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KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5),
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-EINVAL);
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-
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damon_test_split_evenly_fail(test, 0, 100, 0);
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damon_test_split_evenly_succ(test, 0, 100, 10);
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damon_test_split_evenly_succ(test, 5, 59, 5);
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damon_test_split_evenly_succ(test, 4, 6, 1);
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damon_test_split_evenly_succ(test, 0, 3, 2);
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damon_test_split_evenly_fail(test, 5, 6, 2);
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}
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-
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255
static struct kunit_case damon_test_cases[] = {
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KUNIT_CASE(damon_test_three_regions_in_vmas),
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KUNIT_CASE(damon_test_apply_three_regions1),
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KUNIT_CASE(damon_test_apply_three_regions2),
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KUNIT_CASE(damon_test_apply_three_regions3),
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KUNIT_CASE(damon_test_apply_three_regions4),
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KUNIT_CASE(damon_test_split_evenly),
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{},
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};
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+2
-68
mm/damon/vaddr.c
+2
-68
mm/damon/vaddr.c
···
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return mm;
54
54
}
55
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56
-
/*
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* Functions for the initial monitoring target regions construction
58
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*/
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-
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/*
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* Size-evenly split a region into 'nr_pieces' small regions
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*
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* Returns 0 on success, or negative error code otherwise.
64
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*/
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static int damon_va_evenly_split_region(struct damon_target *t,
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struct damon_region *r, unsigned int nr_pieces)
67
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{
68
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unsigned long sz_orig, sz_piece, orig_end;
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struct damon_region *n = NULL, *next;
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unsigned long start;
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unsigned int i;
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-
73
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if (!r || !nr_pieces)
74
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return -EINVAL;
75
-
76
-
if (nr_pieces == 1)
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return 0;
78
-
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orig_end = r->ar.end;
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sz_orig = damon_sz_region(r);
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sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION_SZ);
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-
83
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if (!sz_piece)
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return -EINVAL;
85
-
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r->ar.end = r->ar.start + sz_piece;
87
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next = damon_next_region(r);
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for (start = r->ar.end, i = 1; i < nr_pieces; start += sz_piece, i++) {
89
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n = damon_new_region(start, start + sz_piece);
90
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if (!n)
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return -ENOMEM;
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damon_insert_region(n, r, next, t);
93
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r = n;
94
-
}
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/* complement last region for possible rounding error */
96
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if (n)
97
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n->ar.end = orig_end;
98
-
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return 0;
100
-
}
101
-
102
56
static unsigned long sz_range(struct damon_addr_range *r)
103
57
{
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return r->end - r->start;
···
194
240
struct damon_target *t)
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{
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struct damon_target *ti;
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-
struct damon_region *r;
198
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struct damon_addr_range regions[3];
199
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unsigned long sz = 0, nr_pieces;
200
-
int i, tidx = 0;
244
+
int tidx = 0;
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202
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if (damon_va_three_regions(t, regions)) {
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damon_for_each_target(ti, ctx) {
···
207
255
return;
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256
}
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-
for (i = 0; i < 3; i++)
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sz += regions[i].end - regions[i].start;
212
-
if (ctx->attrs.min_nr_regions)
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sz /= ctx->attrs.min_nr_regions;
214
-
if (sz < DAMON_MIN_REGION_SZ)
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-
sz = DAMON_MIN_REGION_SZ;
216
-
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/* Set the initial three regions of the target */
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for (i = 0; i < 3; i++) {
219
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r = damon_new_region(regions[i].start, regions[i].end);
220
-
if (!r) {
221
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pr_err("%d'th init region creation failed\n", i);
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-
return;
223
-
}
224
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damon_add_region(r, t);
225
-
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-
nr_pieces = (regions[i].end - regions[i].start) / sz;
227
-
damon_va_evenly_split_region(t, r, nr_pieces);
228
-
}
258
+
damon_set_regions(t, regions, 3, DAMON_MIN_REGION_SZ);
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259
}
230
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/* Initialize '->regions_list' of every target (task) */