// Signal tapset
// Copyright (C) 2006 IBM Corp.
// Copyright (C) 2006 Intel Corporation.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.
//
//   Note : Since there are so many signals sent to processes at any give
//          point, it's better to filter the information according to the
//          requirements.  For example, filter only for a particular signal
//          (if sig==2) or filter only for a particular process
//          (if pid_name==stap).
//

/* probe signal.send
 *
 * Fires when a signal is sent to a process.
 *
 */

probe signal.send = _signal.send.*
{
    sig=$sig
    sig_name = _signal_name($sig)
    sig_pid = task_pid(task)
    pid_name = task_execname(task)

    if (sinfo == 2)
        si_code ="SIGSTOP or SIGKILL"
    else if (sinfo > 0)
        si_code="SI_KERNEL (SIGFPE, SIGSEGV, SIGTRAP, SIGCHLD, SIGPOLL)"
    else if (sinfo <= 0)
        si_code="SI_USER or SI_TIMER or SI_ASYNCIO"

    argstr = sprintf("Signal : %s - Process name : %s (%d) - Signal Code : %s",
                     sig_name, sig_pid, pid_name, si_code)
}

probe _signal.send.part1 = kernel.function("__group_send_sig_info")
{
    task = $p
    sinfo = $info
    shared = 1
}

probe _signal.send.part2 = kernel.function("send_group_sigqueue")
{
    task = $p
    sinfo = $q->info
    shared = 1
}

probe _signal.send.part3 = kernel.function("send_sigqueue")
{
    task = $p
    sinfo = $q->info
    shared = 0
}

probe _signal.send.part4 = kernel.function("specific_send_sig_info")
{
    task = $t
    sinfo = $info
    shared = 0
}

/* probe signal.wakeup
 *
 * Wake up the process for new active signals.
 *
 */

probe signal.wakeup = kernel.function("signal_wake_up")
{
    sig_pid = $t->pid
    pid_name = kernel_string($t->comm)
    state   = $resume
    if (state == 0) {
        sig_state = "TASK_INTERRUPTIBLE"
    } else {
        sig_state = "TASK_INTERRUPTIBLE | TASK_STOPPED | TASK_TRACED"
    }
    argstr = sprintf("Wakeup Signal to Process %s (%d) - Process State after the signal : %s",
                     pid_name, sig_pid, sig_state)
}

/* probe signal.ignored
 *
 *  Checks whether the signal is ignored or not.
 *
 */

probe signal.check_ignored = kernel.function("sig_ignored")
{
    sig_pid = $t->pid
    pid_name = kernel_string($t->comm)
    sig_info = $sig
    sig_name = _signal_name($sig)
    argstr = sprintf("Signal : %s is ignored by the Process : %s (%d)",
                     sig_name, pid_name, sig_pid)
}

probe signal.check_ignored.return = kernel.function("sig_ignored").return
{
    name = "sig_ignored"
    retstr = returnstr(1)
}

/* probe signal.handle_stop
 *
 *  Fires when a stop signal is sent to a process.
 *
 */

probe signal.handle_stop = kernel.function("handle_stop_signal")
{
    sig_pid = $p->pid
    pid_name = kernel_string($p->comm)
    sig_info = $sig
    sig_name = _signal_name($sig)
    argstr = sprintf("Handle_Stop_Signal : %s is sent to the process %s (%d)",
                     sig_name, pid_name, sig_pid);
}

/* probe signal.force_segv
 *
 *  Forces SIGSEGV when there are some issues while handling signals for the process.
 *
 */

probe signal.force_segv = kernel.function("force_sigsegv")
{
    sig_pid = $p->pid
    pid_name = kernel_string($p->comm)
    sig_info = $sig
    sig_name = _signal_name($sig)
    argstr = sprintf("Signal < %d > is forced on to the process %s (%d)",
                     sig_name, pid_name, sig_pid);
}

probe signal.force_segv.return = kernel.function("force_sigsegv").return
{
    name = "force_sigsegv"
    retstr = returnstr(1)
}

/* probe signal.syskill
 *
 *  To kill a process, Pass the pid and signal to kill the process.
 *
 */

probe signal.syskill = kernel.function("sys_kill")
{
    sig_pid = $pid
    sig_info = $sig
    argstr = sprintf("Process %d has recieved a Signal %s", sig_pid, sig_name);
}

probe signal.syskill.return = kernel.function("sys_kill").return
{
    name = "sys_kill"
    retstr = returnstr(1)
}

/* probe signal.sys_tgkill
 *
 *  Sends a signal to one specific thread.
 *
 */

probe signal.systgkill = kernel.function("sys_tgkill")
{
    sig_tgid = $tgid
    sig_pid = $pid
    sig_info = $sig
    sig_name = _signal_name($sig)
    argstr = sprintf("Signal %s is sent to Process ID : %d under the Thread Group ID : %d",
                     sig_name, sig_pid, sig_tgid);
}

probe signal.systgkill.return = kernel.function("sys_tgkill").return
{
    name = "sys_tgkill"
    retstr = returnstr(1)
}


/* probe signal.sys_tkill
 *
 *  Sends a signal to one specific task.
 *
 */

probe signal.systkill = kernel.function("sys_tkill")
{
    sig_pid = $pid
    sig_info = $sig
    sig_name = _signal_name($sig)
    argstr = sprintf("Signal %s is sent to Process ID : %d", sig_name, sig_pid);
}

probe signal.systkill.return = kernel.function("sys_tkill").return
{
    name = "sys_tkill"
    retstr = returnstr(1)
}

/* probe signal.send_sig_queue
 *
 * Queue signal to a process.
 *
 */
probe signal.send_sig_queue =
        kernel.function("send_sigqueue"),
        kernel.function("send_group_sigqueue")
{
    sig_info = $sig
    sig_name = _signal_name($sig)
    sig_pid = $p->pid
    pid_name = kernel_string($p->comm)
    user_id = $q->uid
    nos_process = $q->processes
    nos_pending_sig = $q->sigpending
}

probe signal.send_sig_queue.return =
        kernel.function("send_sigqueue").return,
        kernel.function("send_group_sigqueue").return
{
    retstr = returnstr(1)
}

/* probe signal.pend
 *
 * Used to Suspend signals
 *
 * long do_sigpending(void __user *set, unsigned long sigsetsize)
 */

probe signal.pend = kernel.function("do_sigpending")
{
    uspace_add=$set
    sset_size=$sigsetsize
}

probe signal.pend.return = kernel.function("do_sigpending").return
{
    retstr = returnstr(1)
}


/* probe signal.handle
 *
 * Used to invoke signals
 *
 * static int handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 *					sigset_t *oldset, struct pt_regs * regs)
 * Argument :-
 *  sig    : Signal number
 *  info   : address of siginfo table.
 *  ka     : Address of the k_sigaction table associated with the signal
 *  oldset : Address of a bit mask array of blocked signals
 *  regs   : Address in the Kernel Mode stack area w
 *
 */

probe signal.handle = kernel.function("handle_signal")?,
        kernel.inline("handle_signal")?
{
    sig = $sig
    sig_name = _signal_name($sig)
    siginfo_add=$info
    sig_stack_add=$ka
    bitmask_add=$oldset
    kernmode_stack_add=$regs
}

probe signal.handle.return = kernel.function("handle_signal").return
{
    retstr = returnstr(1)
}

/* probe signal.do_action
 *
 * Called by sys_sigaction() to copy the new new_ka table into the entry at the sig-1 position.
 *
 * int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact)
 *
 * Argument :-
 *  sig    : Signal number
 *  act    : Address of the sigaction table associated with the signal
 *  oact   : Address of a previous sigaction table
 *
 */
probe signal.do_action = kernel.function("do_sigaction")
{
    sig = $sig
    siginfo_add=$info
    sig_stack_add=$ka
    bitmask_add=$oldset
    kernmode_stack_add=$regs
}

probe signal.do_action.return = kernel.function("do_sigaction").return
{
    retstr = returnstr(1)
}

/* probe signal.procmask
 *
 * Allows processes to modify the set of blocked signals.
 *
 * int sigprocmask(int how, sigset_t *set, sigset_t *oldset)
 *
 * Argument :-
 *  how    : Flag having one of the values (SIG_BLOCK, SIG_UNBLOCK, SIG_SETMASK)
 *  set    : Address of the process address space to a bit array.
 *  oldset : Address of the process address space where the previous bit mask must be stored.
 *
 */

probe signal.procmask = kernel.function("sigprocmask")
{
    stemp=$how
    sigset=$set
    sigoset=$oldset

    if (stemp == 0)
        sig_how ="SIG_BLOCK"
    else if (stemp ==  1)
        sig_how="SIG_UNBLOCK"
    else if (sinfo == 2)
        sig_how="SIG_SETMASK"
}

probe signal.procmask.return = kernel.function("sigprocmask").return
{
    retstr = returnstr(1)
}