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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
sched_ext: Add time helpers for BPF schedulers
The following functions are added for BPF schedulers:
- time_delta(after, before)
- time_after(a, b)
- time_before(a, b)
- time_after_eq(a, b)
- time_before_eq(a, b)
- time_in_range(a, b, c)
- time_in_range_open(a, b, c)
Signed-off-by: Changwoo Min <changwoo@igalia.com>
Acked-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
authored by
Changwoo Min
and committed by
Tejun Heo
d07be814
2e1ce39f
+94
+94
tools/sched_ext/include/scx/common.bpf.h
+94
tools/sched_ext/include/scx/common.bpf.h
···
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void bpf_rcu_read_lock(void) __ksym;
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void bpf_rcu_read_unlock(void) __ksym;
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/*
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* Time helpers, most of which are from jiffies.h.
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*/
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/**
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* time_delta - Calculate the delta between new and old time stamp
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* @after: first comparable as u64
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* @before: second comparable as u64
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*
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* Return: the time difference, which is >= 0
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*/
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static inline s64 time_delta(u64 after, u64 before)
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{
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return (s64)(after - before) > 0 ? : 0;
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}
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/**
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* time_after - returns true if the time a is after time b.
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* @a: first comparable as u64
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* @b: second comparable as u64
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*
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* Do this with "<0" and ">=0" to only test the sign of the result. A
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* good compiler would generate better code (and a really good compiler
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* wouldn't care). Gcc is currently neither.
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*
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* Return: %true is time a is after time b, otherwise %false.
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*/
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static inline bool time_after(u64 a, u64 b)
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{
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return (s64)(b - a) < 0;
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}
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/**
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* time_before - returns true if the time a is before time b.
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* @a: first comparable as u64
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* @b: second comparable as u64
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*
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* Return: %true is time a is before time b, otherwise %false.
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*/
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static inline bool time_before(u64 a, u64 b)
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{
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return time_after(b, a);
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}
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/**
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* time_after_eq - returns true if the time a is after or the same as time b.
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* @a: first comparable as u64
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* @b: second comparable as u64
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*
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* Return: %true is time a is after or the same as time b, otherwise %false.
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*/
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static inline bool time_after_eq(u64 a, u64 b)
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{
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return (s64)(a - b) >= 0;
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}
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/**
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* time_before_eq - returns true if the time a is before or the same as time b.
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* @a: first comparable as u64
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* @b: second comparable as u64
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*
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* Return: %true is time a is before or the same as time b, otherwise %false.
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*/
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static inline bool time_before_eq(u64 a, u64 b)
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{
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return time_after_eq(b, a);
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}
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/**
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* time_in_range - Calculate whether a is in the range of [b, c].
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* @a: time to test
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* @b: beginning of the range
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* @c: end of the range
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*
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* Return: %true is time a is in the range [b, c], otherwise %false.
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*/
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static inline bool time_in_range(u64 a, u64 b, u64 c)
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{
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return time_after_eq(a, b) && time_before_eq(a, c);
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}
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/**
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* time_in_range_open - Calculate whether a is in the range of [b, c).
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* @a: time to test
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* @b: beginning of the range
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* @c: end of the range
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*
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* Return: %true is time a is in the range [b, c), otherwise %false.
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*/
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static inline bool time_in_range_open(u64 a, u64 b, u64 c)
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{
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return time_after_eq(a, b) && time_before(a, c);
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}
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/*
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* Other helpers