diff options
| author | Yu Kuai <yukuai3@huawei.com> | 2025-08-07 11:24:13 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-08-07 06:30:17 -0600 |
| commit | 45fa9f97e65231a9fd4f9429489cb74c10ccd0fd (patch) | |
| tree | b010fb24fda004641443afdd0dd742aea4501957 /lib/sbitmap.c | |
| parent | 42e6c6ce03fd3e41e39a0f93f9b1a1d9fa664338 (diff) | |
lib/sbitmap: make sbitmap_get_shallow() internal
Because it's only used in sbitmap.c
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20250807032413.1469456-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'lib/sbitmap.c')
| -rw-r--r-- | lib/sbitmap.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/lib/sbitmap.c b/lib/sbitmap.c index c07e3cd82e29..4d188d05db15 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -307,7 +307,22 @@ static int __sbitmap_get_shallow(struct sbitmap *sb, return sbitmap_find_bit(sb, shallow_depth, index, alloc_hint, true); } -int sbitmap_get_shallow(struct sbitmap *sb, unsigned long shallow_depth) +/** + * sbitmap_get_shallow() - Try to allocate a free bit from a &struct sbitmap, + * limiting the depth used from each word. + * @sb: Bitmap to allocate from. + * @shallow_depth: The maximum number of bits to allocate from the bitmap. + * + * This rather specific operation allows for having multiple users with + * different allocation limits. E.g., there can be a high-priority class that + * uses sbitmap_get() and a low-priority class that uses sbitmap_get_shallow() + * with a @shallow_depth of (sb->depth >> 1). Then, the low-priority + * class can only allocate half of the total bits in the bitmap, preventing it + * from starving out the high-priority class. + * + * Return: Non-negative allocated bit number if successful, -1 otherwise. + */ +static int sbitmap_get_shallow(struct sbitmap *sb, unsigned long shallow_depth) { int nr; unsigned int hint, depth; @@ -322,7 +337,6 @@ int sbitmap_get_shallow(struct sbitmap *sb, unsigned long shallow_depth) return nr; } -EXPORT_SYMBOL_GPL(sbitmap_get_shallow); bool sbitmap_any_bit_set(const struct sbitmap *sb) { |