UTRACE_ATTACH_TASK(9) utrace core API UTRACE_ATTACH_TASK(9)NAMEutrace_attach_task - attach new engine, or look up an attached engine
SYNOPSIS
struct utrace_engine * utrace_attach_task(struct task_struct * target,
int flags,
const struct utrace_engine_ops * ops,
void * data);
ARGUMENTS
target
thread to attach to
flags
flag bits combined with OR, see below
ops
callback table for new engine
data
engine private data pointer
DESCRIPTION
The caller must ensure that the target thread does not get freed, i.e.
hold a ref or be its parent. It is always safe to call this on current,
or on the child pointer in a report_clone callback. For most other
cases, it´s easier to use utrace_attach_pid instead.
UTRACE_ATTACH_CREATE
Create a new engine. If UTRACE_ATTACH_CREATE is not specified, you only
look up an existing engine already attached to the thread.
UTRACE_ATTACH_EXCLUSIVE
Attempting to attach a second (matching) engine fails with -EEXIST.
UTRACE_ATTACH_MATCH_OPS
Only consider engines matching ops.
UTRACE_ATTACH_MATCH_DATA
Only consider engines matching data.
Calls with neither UTRACE_ATTACH_MATCH_OPS nor UTRACE_ATTACH_MATCH_DATA
match the first among any engines attached to target. That means that
UTRACE_ATTACH_EXCLUSIVE in such a call fails with -EEXIST if there are
any engines on target at all.
Kernel Hackers Manual 2.6. November 2013 UTRACE_ATTACH_TASK(9)
