函数逻辑报告

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:include\linux\percpu-refcount.h Create Date:2022-07-27 06:40:35
Last Modify:2020-03-12 14:18:49 Copyright©Brick
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函数名称：percpu_ref_tryget_live - try to increment a live percpu refcount*@ref: percpu_ref to try-get* Increment a percpu refcount unless it has already been killed

函数原型：static inline bool percpu_ref_tryget_live(struct percpu_ref *ref)

返回类型：bool

参数：

类型参数名称
struct percpu_ref *ref
257  __percpu乘percpu_count
258  bool ret = false
260  _read_lock() - mark the beginning of an RCU read-side critical section* When synchronize_rcu() is invoked on one CPU while other CPUs* are within RCU read-side critical sections, then the* synchronize_rcu() is guaranteed to block until after all the other
262  如果Internal helper. Don't use outside percpu-refcount proper. The* function doesn't return the pointer and let the caller test it for NULL* because doing so forces the compiler to generate two conditional则
263  this_cpu_inc( * percpu_count)
264  ret = true
265  否则如果非* The low bit of the pointer indicates whether the ref is in percpu * mode; if set, then get/put will manipulate the atomic_t.按位与__PERCPU_REF_DEAD的值则
266  ret等于atomic_long_inc_not_zero( & count)
269  _read_unlock() - marks the end of an RCU read-side critical section.* In most situations, rcu_read_unlock() is immune from deadlock.* However, in kernels built with CONFIG_RCU_BOOST, rcu_read_unlock()
271  返回:ret
调用者
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lookup_ioctx
hd_struct_try_get
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