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bits.bpf.h
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bits.bpf.h
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/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
#ifndef __BITS_BPF_H
#define __BITS_BPF_H
#define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
#define WRITE_ONCE(x, val) ((*(volatile typeof(x) *)&(x)) = val)
static __always_inline u64 log2(u32 v)
{
u32 shift, r;
r = (v > 0xFFFF) << 4; v >>= r;
shift = (v > 0xFF) << 3; v >>= shift; r |= shift;
shift = (v > 0xF) << 2; v >>= shift; r |= shift;
shift = (v > 0x3) << 1; v >>= shift; r |= shift;
r |= (v >> 1);
return r;
}
static __always_inline u64 log2l(u64 v)
{
u32 hi = v >> 32;
if (hi)
return log2(hi) + 32;
else
return log2(v);
}
#endif /* __BITS_BPF_H */