signal.h File Reference

#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/tracepoint.h>
#include <trace/define_trace.h>

Go to the source code of this file.

Macros
#define	TRACE_SYSTEM   signal
#define	_TRACE_SIGNAL_H
#define	TP_STORE_SIGINFO(__entry, info)

Enumerations
enum	{   TRACE_SIGNAL_DELIVERED, TRACE_SIGNAL_IGNORED, TRACE_SIGNAL_ALREADY_PENDING, TRACE_SIGNAL_OVERFLOW_FAIL,   TRACE_SIGNAL_LOSE_INFO }

Functions
	TRACE_EVENT (signal_generate, TP_PROTO(int sig, struct siginfo *info, struct task_struct *task, int group, int result), TP_ARGS(sig, info, task, group, result), TP_STRUCT__entry(__field(int, sig) __field(int, errno) __field(int, code) __array(char, comm, TASK_COMM_LEN) __field(pid_t, pid) __field(int, group) __field(int, result)), TP_fast_assign(__entry->sig=sig;TP_STORE_SIGINFO(__entry, info);memcpy(__entry->comm, task->comm, TASK_COMM_LEN);__entry->pid=task->pid;__entry->group=group;__entry->result=result;), TP_printk("sig=%d errno=%d code=%d comm=%s pid=%d grp=%d res=%d", __entry->sig, __entry->errno, __entry->code, __entry->comm, __entry->pid, __entry->group, __entry->result))
	TRACE_EVENT (signal_deliver, TP_PROTO(int sig, struct siginfo *info, struct k_sigaction *ka), TP_ARGS(sig, info, ka), TP_STRUCT__entry(__field(int, sig) __field(int, errno) __field(int, code) __field(unsigned long, sa_handler) __field(unsigned long, sa_flags)), TP_fast_assign(__entry->sig=sig;TP_STORE_SIGINFO(__entry, info);__entry->sa_handler=(unsigned long) ka->sa.sa_handler;__entry->sa_flags=ka->sa.sa_flags;), TP_printk("sig=%d errno=%d code=%d sa_handler=%lx sa_flags=%lx", __entry->sig, __entry->errno, __entry->code, __entry->sa_handler, __entry->sa_flags))

Macro Definition Documentation

#define _TRACE_SIGNAL_H

Definition at line 5 of file signal.h.

#define TP_STORE_SIGINFO	(		__entry,
			info
	)

Value:

do {                            \
        if (info == SEND_SIG_NOINFO ||          \
            info == SEND_SIG_FORCED) {          \
            __entry->errno  = 0;            \
            __entry->code   = SI_USER;      \
        } else if (info == SEND_SIG_PRIV) {     \
            __entry->errno  = 0;            \
            __entry->code   = SI_KERNEL;        \
        } else {                    \
            __entry->errno  = info->si_errno;   \
            __entry->code   = info->si_code;    \
        }                       \
    } while (0)

Definition at line 11 of file signal.h.

#define TRACE_SYSTEM   signal

Definition at line 2 of file signal.h.

Enumeration Type Documentation

anonymous enum

Enumerator:

TRACE_SIGNAL_DELIVERED
TRACE_SIGNAL_IGNORED
TRACE_SIGNAL_ALREADY_PENDING
TRACE_SIGNAL_OVERFLOW_FAIL
TRACE_SIGNAL_LOSE_INFO

Definition at line 27 of file signal.h.

Function Documentation

TRACE_EVENT	(	signal_generate	,
		TP_PROTO(int sig, struct siginfo *info, struct task_struct *task, int group, int result)	,
		TP_ARGS(sig, info, task, group, result)	,
		TP_STRUCT__entry(__field(int, sig) __field(int, errno) __field(int, code) __array(char, comm, TASK_COMM_LEN) __field(pid_t, pid) __field(int, group) __field(int, result))	,
		TP_fast_assign(__entry->sig=sig;TP_STORE_SIGINFO(__entry, info);memcpy(__entry->comm, task->comm, TASK_COMM_LEN);__entry->pid=task->pid;__entry->group=group;__entry->result=result;)	,
		TP_printk("sig=%d errno=%d code=%d comm=%s pid=%d grp=%d res=%d", __entry->sig, __entry->errno, __entry->code, __entry->comm, __entry->pid, __entry->group, __entry->result)
	)

signal_generate - called when a signal is generated : signal number : pointer to struct siginfo : pointer to struct task_struct : shared or private

Returns

: TRACE_SIGNAL_*

Current process sends a 'sig' signal to 'task' process with 'info' siginfo. If 'info' is SEND_SIG_NOINFO or SEND_SIG_PRIV, 'info' is not a pointer and you can't access its field. Instead, SEND_SIG_NOINFO means that si_code is SI_USER, and SEND_SIG_PRIV means that si_code is SI_KERNEL.

TRACE_EVENT	(	signal_deliver	,
		TP_PROTO(int sig, struct siginfo *info, struct k_sigaction *ka)	,
		TP_ARGS(sig, info, ka)	,
		TP_STRUCT__entry(__field(int, sig) __field(int, errno) __field(int, code) __field(unsigned long, sa_handler) __field(unsigned long, sa_flags))	,
		TP_fast_assign(__entry->sig=sig;TP_STORE_SIGINFO(__entry, info);__entry->sa_handler=(unsigned long) ka->sa.sa_handler;__entry->sa_flags=ka->sa.sa_flags;)	,
		TP_printk("sig=%d errno=%d code=%d sa_handler=%lx sa_flags=%lx", __entry->sig, __entry->errno, __entry->code, __entry->sa_handler, __entry->sa_flags)
	)

signal_deliver - called when a signal is delivered : signal number : pointer to struct siginfo : pointer to struct k_sigaction

A 'sig' signal is delivered to current process with 'info' siginfo, and it will be handled by 'ka'. ka->sa.sa_handler can be SIG_IGN or SIG_DFL. Note that some signals reported by signal_generate tracepoint can be lost, ignored or modified (by debugger) before hitting this tracepoint. This means, this can show which signals are actually delivered, but matching generated signals and delivered signals may not be correct.