Function report

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:kernel\trace\trace.c Create Date:2022-07-28 12:01:59
Last Modify:2020-03-12 14:18:49 Copyright©Brick
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Annotation kernel can get tool activityDownload SCCTChinese

Name:tracing_total_entries_read

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

Type:ssize_t

Parameter:

TypeParameterName
struct file *filp
char __user *ubuf
size_tcnt
loff_t *ppos
6418  tr = needed for tty driver, and maybe others
6421  size = 0 , expanded_size = 0
6423  mutex_lock( & race_types_lock is used to protect the trace_types list.)
6424  for_each_tracing_cpu(cpu)
6425  size += ({
6425  ({
6425  Do
6425  const void * __vpp_verify = NULL
6425  When 0 cycle
6425  data
6425  })
6425  })->entries >> 10
6426  If Not On boot up, the ring buffer is set to the minimum size, so that* we do not waste memory on systems that are not using tracing. Then expanded_size += trace_buf_size >> 10
6429  If On boot up, the ring buffer is set to the minimum size, so that* we do not waste memory on systems that are not using tracing. Then r = sprintf(buf, "%lu\n", size)
6431  Else r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size)
6433  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.
6435  Return simple_read_from_buffer(ubuf, cnt, ppos, buf, r)