Function report

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:kernel\trace\trace.c Create Date:2022-07-28 12:03:10
Last Modify:2020-03-12 14:18:49 Copyright©Brick
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Annotation kernel can get tool activityDownload SCCTChinese

Name:trace_options_core_write

Proto:static ssize_t trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos)

Type:ssize_t

Parameter:

TypeParameterName
struct file *filp
const char __user *ubuf
size_tcnt
loff_t *ppos
8072  tr_index = needed for tty driver, and maybe others
8078  In order to pass in both the trace_array descriptor as well as the index* to the flag that the trace option file represents, the trace_array* has a character array of trace_flags_index[], which holds the index* of the bit for the flag it represents
8080  ret = kstrtoul_from_user(ubuf, cnt, 10, & val)
8081  If ret Then Return ret
8084  If val != 0 && val != 1 Then Return -EINVAL
8087  mutex_lock( & event_mutex)
8088  mutex_lock( & race_types_lock is used to protect the trace_types list.)
8089  ret = set_tracer_flag(tr, 1 << index, val)
8090  mutex_unlock - release the mutex*@lock: the mutex to be released* Unlock a mutex that has been locked by this task previously.* This function must not be used in interrupt context. Unlocking* of a not locked mutex is not allowed.
8091  mutex_unlock - release the mutex*@lock: the mutex to be released* Unlock a mutex that has been locked by this task previously.* This function must not be used in interrupt context. Unlocking* of a not locked mutex is not allowed.
8093  If ret < 0 Then Return ret
8096  ppos += cnt
8098  Return cnt