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authorLinus Torvalds <torvalds@linux-foundation.org>2022-01-23 05:20:44 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2022-01-23 05:20:44 +0100
commit3689f9f8b0c52dfd8f5995e4b58917f8f3ac3ee3 (patch)
treeb9016692f761d50828d745f5bf8c6d727a22134c /lib
parentMerge branch 'akpm' (patches from Andrew) (diff)
parentvsprintf: rework bitmap_list_string (diff)
downloadlinux-3689f9f8b0c52dfd8f5995e4b58917f8f3ac3ee3.tar.xz
linux-3689f9f8b0c52dfd8f5995e4b58917f8f3ac3ee3.zip
Merge tag 'bitmap-5.17-rc1' of git://github.com/norov/linux
Pull bitmap updates from Yury Norov: - introduce for_each_set_bitrange() - use find_first_*_bit() instead of find_next_*_bit() where possible - unify for_each_bit() macros * tag 'bitmap-5.17-rc1' of git://github.com/norov/linux: vsprintf: rework bitmap_list_string lib: bitmap: add performance test for bitmap_print_to_pagebuf bitmap: unify find_bit operations mm/percpu: micro-optimize pcpu_is_populated() Replace for_each_*_bit_from() with for_each_*_bit() where appropriate find: micro-optimize for_each_{set,clear}_bit() include/linux: move for_each_bit() macros from bitops.h to find.h cpumask: replace cpumask_next_* with cpumask_first_* where appropriate tools: sync tools/bitmap with mother linux all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate cpumask: use find_first_and_bit() lib: add find_first_and_bit() arch: remove GENERIC_FIND_FIRST_BIT entirely include: move find.h from asm_generic to linux bitops: move find_bit_*_le functions from le.h to find.h bitops: protect find_first_{,zero}_bit properly
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig3
-rw-r--r--lib/find_bit.c21
-rw-r--r--lib/find_bit_benchmark.c21
-rw-r--r--lib/genalloc.c2
-rw-r--r--lib/test_bitmap.c37
-rw-r--r--lib/vsprintf.c24
6 files changed, 87 insertions, 21 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 51c368a50b16..c80fde816a7e 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -65,9 +65,6 @@ config GENERIC_STRNLEN_USER
config GENERIC_NET_UTILS
bool
-config GENERIC_FIND_FIRST_BIT
- bool
-
source "lib/math/Kconfig"
config NO_GENERIC_PCI_IOPORT_MAP
diff --git a/lib/find_bit.c b/lib/find_bit.c
index 0f8e2e369b1d..1b8e4b2a9cba 100644
--- a/lib/find_bit.c
+++ b/lib/find_bit.c
@@ -89,6 +89,27 @@ unsigned long _find_first_bit(const unsigned long *addr, unsigned long size)
EXPORT_SYMBOL(_find_first_bit);
#endif
+#ifndef find_first_and_bit
+/*
+ * Find the first set bit in two memory regions.
+ */
+unsigned long _find_first_and_bit(const unsigned long *addr1,
+ const unsigned long *addr2,
+ unsigned long size)
+{
+ unsigned long idx, val;
+
+ for (idx = 0; idx * BITS_PER_LONG < size; idx++) {
+ val = addr1[idx] & addr2[idx];
+ if (val)
+ return min(idx * BITS_PER_LONG + __ffs(val), size);
+ }
+
+ return size;
+}
+EXPORT_SYMBOL(_find_first_and_bit);
+#endif
+
#ifndef find_first_zero_bit
/*
* Find the first cleared bit in a memory region.
diff --git a/lib/find_bit_benchmark.c b/lib/find_bit_benchmark.c
index 5637c5711db9..db904b57d4b8 100644
--- a/lib/find_bit_benchmark.c
+++ b/lib/find_bit_benchmark.c
@@ -49,6 +49,25 @@ static int __init test_find_first_bit(void *bitmap, unsigned long len)
return 0;
}
+static int __init test_find_first_and_bit(void *bitmap, const void *bitmap2, unsigned long len)
+{
+ static DECLARE_BITMAP(cp, BITMAP_LEN) __initdata;
+ unsigned long i, cnt;
+ ktime_t time;
+
+ bitmap_copy(cp, bitmap, BITMAP_LEN);
+
+ time = ktime_get();
+ for (cnt = i = 0; i < len; cnt++) {
+ i = find_first_and_bit(cp, bitmap2, len);
+ __clear_bit(i, cp);
+ }
+ time = ktime_get() - time;
+ pr_err("find_first_and_bit: %18llu ns, %6ld iterations\n", time, cnt);
+
+ return 0;
+}
+
static int __init test_find_next_bit(const void *bitmap, unsigned long len)
{
unsigned long i, cnt;
@@ -129,6 +148,7 @@ static int __init find_bit_test(void)
* traverse only part of bitmap to avoid soft lockup.
*/
test_find_first_bit(bitmap, BITMAP_LEN / 10);
+ test_find_first_and_bit(bitmap, bitmap2, BITMAP_LEN / 2);
test_find_next_and_bit(bitmap, bitmap2, BITMAP_LEN);
pr_err("\nStart testing find_bit() with sparse bitmap\n");
@@ -145,6 +165,7 @@ static int __init find_bit_test(void)
test_find_next_zero_bit(bitmap, BITMAP_LEN);
test_find_last_bit(bitmap, BITMAP_LEN);
test_find_first_bit(bitmap, BITMAP_LEN);
+ test_find_first_and_bit(bitmap, bitmap2, BITMAP_LEN);
test_find_next_and_bit(bitmap, bitmap2, BITMAP_LEN);
/*
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 9a57257988c7..00fc50d0a640 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -251,7 +251,7 @@ void gen_pool_destroy(struct gen_pool *pool)
list_del(&chunk->next_chunk);
end_bit = chunk_size(chunk) >> order;
- bit = find_next_bit(chunk->bits, end_bit, 0);
+ bit = find_first_bit(chunk->bits, end_bit);
BUG_ON(bit < end_bit);
vfree(chunk);
diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index d33fa5a61b95..0c82f07f74fc 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -446,6 +446,42 @@ static void __init test_bitmap_parselist(void)
}
}
+static void __init test_bitmap_printlist(void)
+{
+ unsigned long *bmap = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ char expected[256];
+ int ret, slen;
+ ktime_t time;
+
+ if (!buf || !bmap)
+ goto out;
+
+ memset(bmap, -1, PAGE_SIZE);
+ slen = snprintf(expected, 256, "0-%ld", PAGE_SIZE * 8 - 1);
+ if (slen < 0)
+ goto out;
+
+ time = ktime_get();
+ ret = bitmap_print_to_pagebuf(true, buf, bmap, PAGE_SIZE * 8);
+ time = ktime_get() - time;
+
+ if (ret != slen + 1) {
+ pr_err("bitmap_print_to_pagebuf: result is %d, expected %d\n", ret, slen);
+ goto out;
+ }
+
+ if (strncmp(buf, expected, slen)) {
+ pr_err("bitmap_print_to_pagebuf: result is %s, expected %s\n", buf, expected);
+ goto out;
+ }
+
+ pr_err("bitmap_print_to_pagebuf: input is '%s', Time: %llu\n", buf, time);
+out:
+ kfree(buf);
+ kfree(bmap);
+}
+
static const unsigned long parse_test[] __initconst = {
BITMAP_FROM_U64(0),
BITMAP_FROM_U64(1),
@@ -818,6 +854,7 @@ static void __init selftest(void)
test_bitmap_arr32();
test_bitmap_parse();
test_bitmap_parselist();
+ test_bitmap_printlist();
test_mem_optimisations();
test_for_each_set_clump8();
test_bitmap_cut();
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 53d6081f9e8b..3b8129dd374c 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1241,20 +1241,13 @@ char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
struct printf_spec spec, const char *fmt)
{
int nr_bits = max_t(int, spec.field_width, 0);
- /* current bit is 'cur', most recently seen range is [rbot, rtop] */
- int cur, rbot, rtop;
bool first = true;
+ int rbot, rtop;
if (check_pointer(&buf, end, bitmap, spec))
return buf;
- rbot = cur = find_first_bit(bitmap, nr_bits);
- while (cur < nr_bits) {
- rtop = cur;
- cur = find_next_bit(bitmap, nr_bits, cur + 1);
- if (cur < nr_bits && cur <= rtop + 1)
- continue;
-
+ for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) {
if (!first) {
if (buf < end)
*buf = ',';
@@ -1263,15 +1256,12 @@ char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
first = false;
buf = number(buf, end, rbot, default_dec_spec);
- if (rbot < rtop) {
- if (buf < end)
- *buf = '-';
- buf++;
-
- buf = number(buf, end, rtop, default_dec_spec);
- }
+ if (rtop == rbot + 1)
+ continue;
- rbot = cur;
+ if (buf < end)
+ *buf = '-';
+ buf = number(++buf, end, rtop - 1, default_dec_spec);
}
return buf;
}