* [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation
@ 2023-09-25 2:38 Yury Norov
2023-09-25 2:38 ` [PATCH v5 1/8] bitmap: align __reg_op() wrappers with modern coding style Yury Norov
` (8 more replies)
0 siblings, 9 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
bitmap_{allocate,find_free,release}_region() functions are implemented
on top of _reg_op() machinery. It duplicates existing generic functionality
with no benefits. In fact, generic alternatives may work even better
because they optimized for small_const_nbits() case and overall very well
optimized for performance and code generation.
This series drops _reg_op() entirely.
v2: https://lore.kernel.org/lkml/20230811005732.107718-2-yury.norov@gmail.com/T/
v3: https://lore.kernel.org/lkml/20230815233628.45016-2-yury.norov@gmail.com/T/
v4: https://lore.kernel.org/lkml/20230829023911.64335-1-yury.norov@gmail.com/T/
v5: - fix bitmap_release_region() implementation;
- address nits for commits comments.
Yury Norov (8):
bitmap: align __reg_op() wrappers with modern coding style
bitmap: add test for bitmap_*_region() functions
bitmap: fix opencoded bitmap_allocate_region()
bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set()
bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear()
bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit()
bitmap: drop _reg_op() function
bitmap: move bitmap_*_region() functions to bitmap.h
include/linux/bitmap.h | 63 ++++++++++++++++++-
lib/bitmap.c | 140 -----------------------------------------
lib/test_bitmap.c | 24 +++++++
3 files changed, 84 insertions(+), 143 deletions(-)
--
2.39.2
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH v5 1/8] bitmap: align __reg_op() wrappers with modern coding style
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 2/8] bitmap: add test for bitmap_*_region() functions Yury Norov
` (7 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
Fix comments so that scripts/kernel-doc doesn't warn, and fix for-loop
stype in bitmap_find_free_region().
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/bitmap.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index ddb31015e38a..421f2fc384f4 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1234,8 +1234,8 @@ void bitmap_fold(unsigned long *dst, const unsigned long *orig,
* some size '1 << order' (a power of two), aligned to that same
* '1 << order' power of two.
*
- * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits).
- * Returns 0 in all other cases and reg_ops.
+ * Return: 1 if REG_OP_ISFREE succeeds (region is all zero bits).
+ * 0 in all other cases and reg_ops.
*/
enum {
@@ -1307,14 +1307,14 @@ static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_
* a power (@order) of two, aligned to that power of two, which
* makes the search algorithm much faster.
*
- * Return the bit offset in bitmap of the allocated region,
+ * Return: the bit offset in bitmap of the allocated region,
* or -errno on failure.
*/
int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
{
unsigned int pos, end; /* scans bitmap by regions of size order */
- for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) {
+ for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) {
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
continue;
__reg_op(bitmap, pos, order, REG_OP_ALLOC);
@@ -1332,8 +1332,6 @@ EXPORT_SYMBOL(bitmap_find_free_region);
*
* This is the complement to __bitmap_find_free_region() and releases
* the found region (by clearing it in the bitmap).
- *
- * No return value.
*/
void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
{
@@ -1349,7 +1347,7 @@ EXPORT_SYMBOL(bitmap_release_region);
*
* Allocate (set bits in) a specified region of a bitmap.
*
- * Return 0 on success, or %-EBUSY if specified region wasn't
+ * Return: 0 on success, or %-EBUSY if specified region wasn't
* free (not all bits were zero).
*/
int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 2/8] bitmap: add test for bitmap_*_region() functions
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
2023-09-25 2:38 ` [PATCH v5 1/8] bitmap: align __reg_op() wrappers with modern coding style Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 3/8] bitmap: fix opencoded bitmap_allocate_region() Yury Norov
` (6 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
Test basic functionality of bitmap_{allocate,release,find_free}_region()
functions.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/test_bitmap.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index f2ea9f30c7c5..65f22c2578b0 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -330,6 +330,29 @@ static void __init test_copy(void)
expect_eq_pbl("0-108,128-1023", bmap2, 1024);
}
+static void __init test_bitmap_region(void)
+{
+ int pos, order;
+
+ DECLARE_BITMAP(bmap, 1000);
+
+ bitmap_zero(bmap, 1000);
+
+ for (order = 0; order < 10; order++) {
+ pos = bitmap_find_free_region(bmap, 1000, order);
+ if (order == 0)
+ expect_eq_uint(pos, 0);
+ else
+ expect_eq_uint(pos, order < 9 ? BIT(order) : -ENOMEM);
+ }
+
+ bitmap_release_region(bmap, 0, 0);
+ for (order = 1; order < 9; order++)
+ bitmap_release_region(bmap, BIT(order), order);
+
+ expect_eq_uint(bitmap_weight(bmap, 1000), 0);
+}
+
#define EXP2_IN_BITS (sizeof(exp2) * 8)
static void __init test_replace(void)
@@ -1227,6 +1250,7 @@ static void __init selftest(void)
test_zero_clear();
test_fill_set();
test_copy();
+ test_bitmap_region();
test_replace();
test_bitmap_arr32();
test_bitmap_arr64();
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 3/8] bitmap: fix opencoded bitmap_allocate_region()
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
2023-09-25 2:38 ` [PATCH v5 1/8] bitmap: align __reg_op() wrappers with modern coding style Yury Norov
2023-09-25 2:38 ` [PATCH v5 2/8] bitmap: add test for bitmap_*_region() functions Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 4/8] bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set() Yury Norov
` (5 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
bitmap_find_region() opencodes bitmap_allocate_region().
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/bitmap.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 421f2fc384f4..cb77b6b0e5e0 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1315,10 +1315,8 @@ int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
unsigned int pos, end; /* scans bitmap by regions of size order */
for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) {
- if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
- continue;
- __reg_op(bitmap, pos, order, REG_OP_ALLOC);
- return pos;
+ if (!bitmap_allocate_region(bitmap, pos, order))
+ return pos;
}
return -ENOMEM;
}
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 4/8] bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set()
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
` (2 preceding siblings ...)
2023-09-25 2:38 ` [PATCH v5 3/8] bitmap: fix opencoded bitmap_allocate_region() Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 5/8] bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear() Yury Norov
` (4 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
_reg_op(REG_OP_ALLOC) duplicates bitmap_set().
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/bitmap.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index cb77b6b0e5e0..a463125560c3 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1350,9 +1350,12 @@ EXPORT_SYMBOL(bitmap_release_region);
*/
int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
{
+ unsigned int len = BIT(order);
+
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
return -EBUSY;
- return __reg_op(bitmap, pos, order, REG_OP_ALLOC);
+ bitmap_set(bitmap, pos, len);
+ return 0;
}
EXPORT_SYMBOL(bitmap_allocate_region);
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 5/8] bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear()
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
` (3 preceding siblings ...)
2023-09-25 2:38 ` [PATCH v5 4/8] bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set() Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 6/8] bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit() Yury Norov
` (3 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
_reg_op(REG_OP_RELEASE) duplicates bitmap_clear().
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/bitmap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index a463125560c3..4dba15f2e970 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1333,7 +1333,7 @@ EXPORT_SYMBOL(bitmap_find_free_region);
*/
void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
{
- __reg_op(bitmap, pos, order, REG_OP_RELEASE);
+ bitmap_clear(bitmap, pos, BIT(order));
}
EXPORT_SYMBOL(bitmap_release_region);
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 6/8] bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit()
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
` (4 preceding siblings ...)
2023-09-25 2:38 ` [PATCH v5 5/8] bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear() Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 7/8] bitmap: drop _reg_op() function Yury Norov
` (2 subsequent siblings)
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
_reg_op(REG_OP_ISFREE) can be trivially replaced with find_next_bit().
Doing that opens room for potential small_const_nbits() optimization.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/bitmap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 4dba15f2e970..9345a6ffe39d 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1352,7 +1352,7 @@ int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
{
unsigned int len = BIT(order);
- if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
+ if (find_next_bit(bitmap, pos + len, pos) < pos + len)
return -EBUSY;
bitmap_set(bitmap, pos, len);
return 0;
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 7/8] bitmap: drop _reg_op() function
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
` (5 preceding siblings ...)
2023-09-25 2:38 ` [PATCH v5 6/8] bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit() Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-09-25 2:38 ` [PATCH v5 8/8] bitmap: move bitmap_*_region() functions to bitmap.h Yury Norov
2023-10-06 16:44 ` [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
Now that all _reg_op() users are switched to alternative functions,
_reg_op() machinery is not needed anymore.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
lib/bitmap.c | 76 ----------------------------------------------------
1 file changed, 76 deletions(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 9345a6ffe39d..cc6180dd6254 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1220,82 +1220,6 @@ void bitmap_fold(unsigned long *dst, const unsigned long *orig,
}
#endif /* CONFIG_NUMA */
-/*
- * Common code for bitmap_*_region() routines.
- * bitmap: array of unsigned longs corresponding to the bitmap
- * pos: the beginning of the region
- * order: region size (log base 2 of number of bits)
- * reg_op: operation(s) to perform on that region of bitmap
- *
- * Can set, verify and/or release a region of bits in a bitmap,
- * depending on which combination of REG_OP_* flag bits is set.
- *
- * A region of a bitmap is a sequence of bits in the bitmap, of
- * some size '1 << order' (a power of two), aligned to that same
- * '1 << order' power of two.
- *
- * Return: 1 if REG_OP_ISFREE succeeds (region is all zero bits).
- * 0 in all other cases and reg_ops.
- */
-
-enum {
- REG_OP_ISFREE, /* true if region is all zero bits */
- REG_OP_ALLOC, /* set all bits in region */
- REG_OP_RELEASE, /* clear all bits in region */
-};
-
-static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op)
-{
- int nbits_reg; /* number of bits in region */
- int index; /* index first long of region in bitmap */
- int offset; /* bit offset region in bitmap[index] */
- int nlongs_reg; /* num longs spanned by region in bitmap */
- int nbitsinlong; /* num bits of region in each spanned long */
- unsigned long mask; /* bitmask for one long of region */
- int i; /* scans bitmap by longs */
- int ret = 0; /* return value */
-
- /*
- * Either nlongs_reg == 1 (for small orders that fit in one long)
- * or (offset == 0 && mask == ~0UL) (for larger multiword orders.)
- */
- nbits_reg = 1 << order;
- index = pos / BITS_PER_LONG;
- offset = pos - (index * BITS_PER_LONG);
- nlongs_reg = BITS_TO_LONGS(nbits_reg);
- nbitsinlong = min(nbits_reg, BITS_PER_LONG);
-
- /*
- * Can't do "mask = (1UL << nbitsinlong) - 1", as that
- * overflows if nbitsinlong == BITS_PER_LONG.
- */
- mask = (1UL << (nbitsinlong - 1));
- mask += mask - 1;
- mask <<= offset;
-
- switch (reg_op) {
- case REG_OP_ISFREE:
- for (i = 0; i < nlongs_reg; i++) {
- if (bitmap[index + i] & mask)
- goto done;
- }
- ret = 1; /* all bits in region free (zero) */
- break;
-
- case REG_OP_ALLOC:
- for (i = 0; i < nlongs_reg; i++)
- bitmap[index + i] |= mask;
- break;
-
- case REG_OP_RELEASE:
- for (i = 0; i < nlongs_reg; i++)
- bitmap[index + i] &= ~mask;
- break;
- }
-done:
- return ret;
-}
-
/**
* bitmap_find_free_region - find a contiguous aligned mem region
* @bitmap: array of unsigned longs corresponding to the bitmap
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v5 8/8] bitmap: move bitmap_*_region() functions to bitmap.h
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
` (6 preceding siblings ...)
2023-09-25 2:38 ` [PATCH v5 7/8] bitmap: drop _reg_op() function Yury Norov
@ 2023-09-25 2:38 ` Yury Norov
2023-10-06 16:44 ` [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
8 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-09-25 2:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Yury Norov, Andy Shevchenko, Rasmus Villemoes
Now that bitmap_*_region() functions are implemented as thin wrappers
around others, it's worth to move them to the header, as it opens room
for compile-time optimizations.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
include/linux/bitmap.h | 63 ++++++++++++++++++++++++++++++++++++++++--
lib/bitmap.c | 63 ------------------------------------------
2 files changed, 60 insertions(+), 66 deletions(-)
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 03644237e1ef..9b097f83d785 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -216,9 +216,6 @@ void bitmap_onto(unsigned long *dst, const unsigned long *orig,
const unsigned long *relmap, unsigned int bits);
void bitmap_fold(unsigned long *dst, const unsigned long *orig,
unsigned int sz, unsigned int nbits);
-int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
-void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
-int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
#ifdef __BIG_ENDIAN
void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
@@ -518,6 +515,66 @@ static inline void bitmap_next_set_region(unsigned long *bitmap,
*re = find_next_zero_bit(bitmap, end, *rs + 1);
}
+/**
+ * bitmap_release_region - release allocated bitmap region
+ * @bitmap: array of unsigned longs corresponding to the bitmap
+ * @pos: beginning of bit region to release
+ * @order: region size (log base 2 of number of bits) to release
+ *
+ * This is the complement to __bitmap_find_free_region() and releases
+ * the found region (by clearing it in the bitmap).
+ */
+static inline void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
+{
+ bitmap_clear(bitmap, pos, BIT(order));
+}
+
+/**
+ * bitmap_allocate_region - allocate bitmap region
+ * @bitmap: array of unsigned longs corresponding to the bitmap
+ * @pos: beginning of bit region to allocate
+ * @order: region size (log base 2 of number of bits) to allocate
+ *
+ * Allocate (set bits in) a specified region of a bitmap.
+ *
+ * Returns: 0 on success, or %-EBUSY if specified region wasn't
+ * free (not all bits were zero).
+ */
+static inline int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
+{
+ unsigned int len = BIT(order);
+
+ if (find_next_bit(bitmap, pos + len, pos) < pos + len)
+ return -EBUSY;
+ bitmap_set(bitmap, pos, len);
+ return 0;
+}
+
+/**
+ * bitmap_find_free_region - find a contiguous aligned mem region
+ * @bitmap: array of unsigned longs corresponding to the bitmap
+ * @bits: number of bits in the bitmap
+ * @order: region size (log base 2 of number of bits) to find
+ *
+ * Find a region of free (zero) bits in a @bitmap of @bits bits and
+ * allocate them (set them to one). Only consider regions of length
+ * a power (@order) of two, aligned to that power of two, which
+ * makes the search algorithm much faster.
+ *
+ * Returns: the bit offset in bitmap of the allocated region,
+ * or -errno on failure.
+ */
+static inline int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
+{
+ unsigned int pos, end; /* scans bitmap by regions of size order */
+
+ for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) {
+ if (!bitmap_allocate_region(bitmap, pos, order))
+ return pos;
+ }
+ return -ENOMEM;
+}
+
/**
* BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap.
* @n: u64 value
diff --git a/lib/bitmap.c b/lib/bitmap.c
index cc6180dd6254..1c5d1f5d2071 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1220,69 +1220,6 @@ void bitmap_fold(unsigned long *dst, const unsigned long *orig,
}
#endif /* CONFIG_NUMA */
-/**
- * bitmap_find_free_region - find a contiguous aligned mem region
- * @bitmap: array of unsigned longs corresponding to the bitmap
- * @bits: number of bits in the bitmap
- * @order: region size (log base 2 of number of bits) to find
- *
- * Find a region of free (zero) bits in a @bitmap of @bits bits and
- * allocate them (set them to one). Only consider regions of length
- * a power (@order) of two, aligned to that power of two, which
- * makes the search algorithm much faster.
- *
- * Return: the bit offset in bitmap of the allocated region,
- * or -errno on failure.
- */
-int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
-{
- unsigned int pos, end; /* scans bitmap by regions of size order */
-
- for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) {
- if (!bitmap_allocate_region(bitmap, pos, order))
- return pos;
- }
- return -ENOMEM;
-}
-EXPORT_SYMBOL(bitmap_find_free_region);
-
-/**
- * bitmap_release_region - release allocated bitmap region
- * @bitmap: array of unsigned longs corresponding to the bitmap
- * @pos: beginning of bit region to release
- * @order: region size (log base 2 of number of bits) to release
- *
- * This is the complement to __bitmap_find_free_region() and releases
- * the found region (by clearing it in the bitmap).
- */
-void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
-{
- bitmap_clear(bitmap, pos, BIT(order));
-}
-EXPORT_SYMBOL(bitmap_release_region);
-
-/**
- * bitmap_allocate_region - allocate bitmap region
- * @bitmap: array of unsigned longs corresponding to the bitmap
- * @pos: beginning of bit region to allocate
- * @order: region size (log base 2 of number of bits) to allocate
- *
- * Allocate (set bits in) a specified region of a bitmap.
- *
- * Return: 0 on success, or %-EBUSY if specified region wasn't
- * free (not all bits were zero).
- */
-int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
-{
- unsigned int len = BIT(order);
-
- if (find_next_bit(bitmap, pos + len, pos) < pos + len)
- return -EBUSY;
- bitmap_set(bitmap, pos, len);
- return 0;
-}
-EXPORT_SYMBOL(bitmap_allocate_region);
-
/**
* bitmap_copy_le - copy a bitmap, putting the bits into little-endian order.
* @dst: destination buffer
--
2.39.2
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
` (7 preceding siblings ...)
2023-09-25 2:38 ` [PATCH v5 8/8] bitmap: move bitmap_*_region() functions to bitmap.h Yury Norov
@ 2023-10-06 16:44 ` Yury Norov
2023-10-15 2:58 ` Yury Norov
8 siblings, 1 reply; 11+ messages in thread
From: Yury Norov @ 2023-10-06 16:44 UTC (permalink / raw)
To: linux-kernel; +Cc: Andy Shevchenko, Rasmus Villemoes
Ping?
On Sun, Sep 24, 2023 at 07:38:09PM -0700, Yury Norov wrote:
> bitmap_{allocate,find_free,release}_region() functions are implemented
> on top of _reg_op() machinery. It duplicates existing generic functionality
> with no benefits. In fact, generic alternatives may work even better
> because they optimized for small_const_nbits() case and overall very well
> optimized for performance and code generation.
>
> This series drops _reg_op() entirely.
>
> v2: https://lore.kernel.org/lkml/20230811005732.107718-2-yury.norov@gmail.com/T/
> v3: https://lore.kernel.org/lkml/20230815233628.45016-2-yury.norov@gmail.com/T/
> v4: https://lore.kernel.org/lkml/20230829023911.64335-1-yury.norov@gmail.com/T/
> v5: - fix bitmap_release_region() implementation;
> - address nits for commits comments.
>
> Yury Norov (8):
> bitmap: align __reg_op() wrappers with modern coding style
> bitmap: add test for bitmap_*_region() functions
> bitmap: fix opencoded bitmap_allocate_region()
> bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set()
> bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear()
> bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit()
> bitmap: drop _reg_op() function
> bitmap: move bitmap_*_region() functions to bitmap.h
>
> include/linux/bitmap.h | 63 ++++++++++++++++++-
> lib/bitmap.c | 140 -----------------------------------------
> lib/test_bitmap.c | 24 +++++++
> 3 files changed, 84 insertions(+), 143 deletions(-)
>
> --
> 2.39.2
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation
2023-10-06 16:44 ` [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
@ 2023-10-15 2:58 ` Yury Norov
0 siblings, 0 replies; 11+ messages in thread
From: Yury Norov @ 2023-10-15 2:58 UTC (permalink / raw)
To: linux-kernel; +Cc: Andy Shevchenko, Rasmus Villemoes
OK, if no objections, moving this to bitmap-for-next.
On Fri, Oct 06, 2023 at 09:44:04AM -0700, Yury Norov wrote:
> Ping?
>
> On Sun, Sep 24, 2023 at 07:38:09PM -0700, Yury Norov wrote:
> > bitmap_{allocate,find_free,release}_region() functions are implemented
> > on top of _reg_op() machinery. It duplicates existing generic functionality
> > with no benefits. In fact, generic alternatives may work even better
> > because they optimized for small_const_nbits() case and overall very well
> > optimized for performance and code generation.
> >
> > This series drops _reg_op() entirely.
> >
> > v2: https://lore.kernel.org/lkml/20230811005732.107718-2-yury.norov@gmail.com/T/
> > v3: https://lore.kernel.org/lkml/20230815233628.45016-2-yury.norov@gmail.com/T/
> > v4: https://lore.kernel.org/lkml/20230829023911.64335-1-yury.norov@gmail.com/T/
> > v5: - fix bitmap_release_region() implementation;
> > - address nits for commits comments.
> >
> > Yury Norov (8):
> > bitmap: align __reg_op() wrappers with modern coding style
> > bitmap: add test for bitmap_*_region() functions
> > bitmap: fix opencoded bitmap_allocate_region()
> > bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set()
> > bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear()
> > bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit()
> > bitmap: drop _reg_op() function
> > bitmap: move bitmap_*_region() functions to bitmap.h
> >
> > include/linux/bitmap.h | 63 ++++++++++++++++++-
> > lib/bitmap.c | 140 -----------------------------------------
> > lib/test_bitmap.c | 24 +++++++
> > 3 files changed, 84 insertions(+), 143 deletions(-)
> >
> > --
> > 2.39.2
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2023-10-15 2:58 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-09-25 2:38 [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
2023-09-25 2:38 ` [PATCH v5 1/8] bitmap: align __reg_op() wrappers with modern coding style Yury Norov
2023-09-25 2:38 ` [PATCH v5 2/8] bitmap: add test for bitmap_*_region() functions Yury Norov
2023-09-25 2:38 ` [PATCH v5 3/8] bitmap: fix opencoded bitmap_allocate_region() Yury Norov
2023-09-25 2:38 ` [PATCH v5 4/8] bitmap: replace _reg_op(REG_OP_ALLOC) with bitmap_set() Yury Norov
2023-09-25 2:38 ` [PATCH v5 5/8] bitmap: replace _reg_op(REG_OP_RELEASE) with bitmap_clear() Yury Norov
2023-09-25 2:38 ` [PATCH v5 6/8] bitmap: replace _reg_op(REG_OP_ISFREE) with find_next_bit() Yury Norov
2023-09-25 2:38 ` [PATCH v5 7/8] bitmap: drop _reg_op() function Yury Norov
2023-09-25 2:38 ` [PATCH v5 8/8] bitmap: move bitmap_*_region() functions to bitmap.h Yury Norov
2023-10-06 16:44 ` [PATCH v5 0/8] bitmap: cleanup bitmap_*_region() implementation Yury Norov
2023-10-15 2:58 ` Yury Norov
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