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Commit 55c0d1f8 authored by Roland McGrath's avatar Roland McGrath Committed by Linus Torvalds
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Move sig_kernel_* et al macros to linux/signal.h 

This patch moves the sig_kernel_* and related macros from kernel/signal.c
to linux/signal.h, and cleans them up slightly.  I need the sig_kernel_*
macros for default signal behavior in the utrace code, and want to avoid
duplication or overhead to share the knowledge.
Signed-off-by: default avatarRoland McGrath <roland@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 84963048
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Showing with 125 additions and 119 deletions
include/linux/signal.h
View file @ 55c0d1f8
...@@ -243,6 +243,131 @@ extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, ...@@ -243,6 +243,131 @@ extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
extern struct kmem_cache *sighand_cachep; extern struct kmem_cache *sighand_cachep;
/*
* In POSIX a signal is sent either to a specific thread (Linux task)
* or to the process as a whole (Linux thread group). How the signal
* is sent determines whether it's to one thread or the whole group,
* which determines which signal mask(s) are involved in blocking it
* from being delivered until later. When the signal is delivered,
* either it's caught or ignored by a user handler or it has a default
* effect that applies to the whole thread group (POSIX process).
*
* The possible effects an unblocked signal set to SIG_DFL can have are:
* ignore - Nothing Happens
* terminate - kill the process, i.e. all threads in the group,
* similar to exit_group. The group leader (only) reports
* WIFSIGNALED status to its parent.
* coredump - write a core dump file describing all threads using
* the same mm and then kill all those threads
* stop - stop all the threads in the group, i.e. TASK_STOPPED state
*
* SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.
* Other signals when not blocked and set to SIG_DFL behaves as follows.
* The job control signals also have other special effects.
*
* +--------------------+------------------+
* | POSIX signal | default action |
* +--------------------+------------------+
* | SIGHUP | terminate |
* | SIGINT | terminate |
* | SIGQUIT | coredump |
* | SIGILL | coredump |
* | SIGTRAP | coredump |
* | SIGABRT/SIGIOT | coredump |
* | SIGBUS | coredump |
* | SIGFPE | coredump |
* | SIGKILL | terminate(+) |
* | SIGUSR1 | terminate |
* | SIGSEGV | coredump |
* | SIGUSR2 | terminate |
* | SIGPIPE | terminate |
* | SIGALRM | terminate |
* | SIGTERM | terminate |
* | SIGCHLD | ignore |
* | SIGCONT | ignore(*) |
* | SIGSTOP | stop(*)(+) |
* | SIGTSTP | stop(*) |
* | SIGTTIN | stop(*) |
* | SIGTTOU | stop(*) |
* | SIGURG | ignore |
* | SIGXCPU | coredump |
* | SIGXFSZ | coredump |
* | SIGVTALRM | terminate |
* | SIGPROF | terminate |
* | SIGPOLL/SIGIO | terminate |
* | SIGSYS/SIGUNUSED | coredump |
* | SIGSTKFLT | terminate |
* | SIGWINCH | ignore |
* | SIGPWR | terminate |
* | SIGRTMIN-SIGRTMAX | terminate |
* +--------------------+------------------+
* | non-POSIX signal | default action |
* +--------------------+------------------+
* | SIGEMT | coredump |
* +--------------------+------------------+
*
* (+) For SIGKILL and SIGSTOP the action is "always", not just "default".
* (*) Special job control effects:
* When SIGCONT is sent, it resumes the process (all threads in the group)
* from TASK_STOPPED state and also clears any pending/queued stop signals
* (any of those marked with "stop(*)"). This happens regardless of blocking,
* catching, or ignoring SIGCONT. When any stop signal is sent, it clears
* any pending/queued SIGCONT signals; this happens regardless of blocking,
* catching, or ignored the stop signal, though (except for SIGSTOP) the
* default action of stopping the process may happen later or never.
*/
#ifdef SIGEMT
#define SIGEMT_MASK rt_sigmask(SIGEMT)
#else
#define SIGEMT_MASK 0
#endif
#if SIGRTMIN > BITS_PER_LONG
#define rt_sigmask(sig) (1ULL << ((sig)-1))
#else
#define rt_sigmask(sig) sigmask(sig)
#endif
#define siginmask(sig, mask) (rt_sigmask(sig) & (mask))
#define SIG_KERNEL_ONLY_MASK (\
rt_sigmask(SIGKILL) | rt_sigmask(SIGSTOP))
#define SIG_KERNEL_STOP_MASK (\
rt_sigmask(SIGSTOP) | rt_sigmask(SIGTSTP) | \
rt_sigmask(SIGTTIN) | rt_sigmask(SIGTTOU) )
#define SIG_KERNEL_COREDUMP_MASK (\
rt_sigmask(SIGQUIT) | rt_sigmask(SIGILL) | \
rt_sigmask(SIGTRAP) | rt_sigmask(SIGABRT) | \
rt_sigmask(SIGFPE) | rt_sigmask(SIGSEGV) | \
rt_sigmask(SIGBUS) | rt_sigmask(SIGSYS) | \
rt_sigmask(SIGXCPU) | rt_sigmask(SIGXFSZ) | \
SIGEMT_MASK )
#define SIG_KERNEL_IGNORE_MASK (\
rt_sigmask(SIGCONT) | rt_sigmask(SIGCHLD) | \
rt_sigmask(SIGWINCH) | rt_sigmask(SIGURG) )
#define sig_kernel_only(sig) \
(((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_ONLY_MASK))
#define sig_kernel_coredump(sig) \
(((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_COREDUMP_MASK))
#define sig_kernel_ignore(sig) \
(((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_IGNORE_MASK))
#define sig_kernel_stop(sig) \
(((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_STOP_MASK))
#define sig_needs_tasklist(sig) ((sig) == SIGCONT)
#define sig_user_defined(t, signr) \
(((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_DFL) && \
((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_IGN))
#define sig_fatal(t, signr) \
(!siginmask(signr, SIG_KERNEL_IGNORE_MASK|SIG_KERNEL_STOP_MASK) && \
(t)->sighand->action[(signr)-1].sa.sa_handler == SIG_DFL)
#endif /* __KERNEL__ */ #endif /* __KERNEL__ */
#endif /* _LINUX_SIGNAL_H */ #endif /* _LINUX_SIGNAL_H */
kernel/signal.c
View file @ 55c0d1f8
...@@ -38,125 +38,6 @@ ...@@ -38,125 +38,6 @@
static struct kmem_cache *sigqueue_cachep; static struct kmem_cache *sigqueue_cachep;
/*
* In POSIX a signal is sent either to a specific thread (Linux task)
* or to the process as a whole (Linux thread group). How the signal
* is sent determines whether it's to one thread or the whole group,
* which determines which signal mask(s) are involved in blocking it
* from being delivered until later. When the signal is delivered,
* either it's caught or ignored by a user handler or it has a default
* effect that applies to the whole thread group (POSIX process).
*
* The possible effects an unblocked signal set to SIG_DFL can have are:
* ignore - Nothing Happens
* terminate - kill the process, i.e. all threads in the group,
* similar to exit_group. The group leader (only) reports
* WIFSIGNALED status to its parent.
* coredump - write a core dump file describing all threads using
* the same mm and then kill all those threads
* stop - stop all the threads in the group, i.e. TASK_STOPPED state
*
* SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.
* Other signals when not blocked and set to SIG_DFL behaves as follows.
* The job control signals also have other special effects.
*
* +--------------------+------------------+
* | POSIX signal | default action |
* +--------------------+------------------+
* | SIGHUP | terminate |
* | SIGINT | terminate |
* | SIGQUIT | coredump |
* | SIGILL | coredump |
* | SIGTRAP | coredump |
* | SIGABRT/SIGIOT | coredump |
* | SIGBUS | coredump |
* | SIGFPE | coredump |
* | SIGKILL | terminate(+) |
* | SIGUSR1 | terminate |
* | SIGSEGV | coredump |
* | SIGUSR2 | terminate |
* | SIGPIPE | terminate |
* | SIGALRM | terminate |
* | SIGTERM | terminate |
* | SIGCHLD | ignore |
* | SIGCONT | ignore(*) |
* | SIGSTOP | stop(*)(+) |
* | SIGTSTP | stop(*) |
* | SIGTTIN | stop(*) |
* | SIGTTOU | stop(*) |
* | SIGURG | ignore |
* | SIGXCPU | coredump |
* | SIGXFSZ | coredump |
* | SIGVTALRM | terminate |
* | SIGPROF | terminate |
* | SIGPOLL/SIGIO | terminate |
* | SIGSYS/SIGUNUSED | coredump |
* | SIGSTKFLT | terminate |
* | SIGWINCH | ignore |
* | SIGPWR | terminate |
* | SIGRTMIN-SIGRTMAX | terminate |
* +--------------------+------------------+
* | non-POSIX signal | default action |
* +--------------------+------------------+
* | SIGEMT | coredump |
* +--------------------+------------------+
*
* (+) For SIGKILL and SIGSTOP the action is "always", not just "default".
* (*) Special job control effects:
* When SIGCONT is sent, it resumes the process (all threads in the group)
* from TASK_STOPPED state and also clears any pending/queued stop signals
* (any of those marked with "stop(*)"). This happens regardless of blocking,
* catching, or ignoring SIGCONT. When any stop signal is sent, it clears
* any pending/queued SIGCONT signals; this happens regardless of blocking,
* catching, or ignored the stop signal, though (except for SIGSTOP) the
* default action of stopping the process may happen later or never.
*/
#ifdef SIGEMT
#define M_SIGEMT M(SIGEMT)
#else
#define M_SIGEMT 0
#endif
#if SIGRTMIN > BITS_PER_LONG
#define M(sig) (1ULL << ((sig)-1))
#else
#define M(sig) (1UL << ((sig)-1))
#endif
#define T(sig, mask) (M(sig) & (mask))
#define SIG_KERNEL_ONLY_MASK (\
M(SIGKILL) | M(SIGSTOP) )
#define SIG_KERNEL_STOP_MASK (\
M(SIGSTOP) | M(SIGTSTP) | M(SIGTTIN) | M(SIGTTOU) )
#define SIG_KERNEL_COREDUMP_MASK (\
M(SIGQUIT) | M(SIGILL) | M(SIGTRAP) | M(SIGABRT) | \
M(SIGFPE) | M(SIGSEGV) | M(SIGBUS) | M(SIGSYS) | \
M(SIGXCPU) | M(SIGXFSZ) | M_SIGEMT )
#define SIG_KERNEL_IGNORE_MASK (\
M(SIGCONT) | M(SIGCHLD) | M(SIGWINCH) | M(SIGURG) )
#define sig_kernel_only(sig) \
(((sig) < SIGRTMIN) && T(sig, SIG_KERNEL_ONLY_MASK))
#define sig_kernel_coredump(sig) \
(((sig) < SIGRTMIN) && T(sig, SIG_KERNEL_COREDUMP_MASK))
#define sig_kernel_ignore(sig) \
(((sig) < SIGRTMIN) && T(sig, SIG_KERNEL_IGNORE_MASK))
#define sig_kernel_stop(sig) \
(((sig) < SIGRTMIN) && T(sig, SIG_KERNEL_STOP_MASK))
#define sig_needs_tasklist(sig) ((sig) == SIGCONT)
#define sig_user_defined(t, signr) \
(((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_DFL) && \
((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_IGN))
#define sig_fatal(t, signr) \
(!T(signr, SIG_KERNEL_IGNORE_MASK|SIG_KERNEL_STOP_MASK) && \
(t)->sighand->action[(signr)-1].sa.sa_handler == SIG_DFL)
static int sig_ignored(struct task_struct *t, int sig) static int sig_ignored(struct task_struct *t, int sig)
{ {
......
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