79c8264e44
As is_power_of_two takes unsigned long, it's not safe on 32bit architectures, but we could pass any u64 value in seveal places. Add a separate helper and also an alias that better expresses the purpose for which the helper is used. Signed-off-by: David Sterba <dsterba@suse.com>
62 lines
1.3 KiB
C
62 lines
1.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef BTRFS_MISC_H
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#define BTRFS_MISC_H
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#include <linux/sched.h>
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#include <linux/wait.h>
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#include <asm/div64.h>
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#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
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static inline void cond_wake_up(struct wait_queue_head *wq)
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{
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/*
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* This implies a full smp_mb barrier, see comments for
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* waitqueue_active why.
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*/
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if (wq_has_sleeper(wq))
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wake_up(wq);
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}
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static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
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{
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/*
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* Special case for conditional wakeup where the barrier required for
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* waitqueue_active is implied by some of the preceding code. Eg. one
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* of such atomic operations (atomic_dec_and_return, ...), or a
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* unlock/lock sequence, etc.
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*/
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if (waitqueue_active(wq))
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wake_up(wq);
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}
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static inline u64 div_factor(u64 num, int factor)
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{
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if (factor == 10)
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return num;
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num *= factor;
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return div_u64(num, 10);
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}
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static inline u64 div_factor_fine(u64 num, int factor)
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{
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if (factor == 100)
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return num;
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num *= factor;
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return div_u64(num, 100);
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}
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/* Copy of is_power_of_two that is 64bit safe */
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static inline bool is_power_of_two_u64(u64 n)
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{
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return n != 0 && (n & (n - 1)) == 0;
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}
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static inline bool has_single_bit_set(u64 n)
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{
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return is_power_of_two_u64(n);
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}
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#endif
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