[PATCH 05/31] add utrace hooks into sig_ignored() and recalc_sigpending()

[Oleg Nesterov]

Add the necessary and somewhat "special" hooks into sig_ignored() and
recalc_sigpending(). Basically this restores _force_sigpending() and
_consider_ignored_signal() tracehook logic.

Signed-off-by: Oleg Nesterov <o...@redhat.com>
---
 include/linux/utrace.h |    2 ++
 kernel/signal.c        |    7 ++++++-
 2 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/include/linux/utrace.h b/include/linux/utrace.h
index f251efe..1b8da1c 100644
--- a/include/linux/utrace.h
+++ b/include/linux/utrace.h
@@ -107,6 +107,8 @@ bool utrace_report_syscall_entry(struct pt_regs *);
 void utrace_report_syscall_exit(struct pt_regs *);
 void utrace_signal_handler(struct task_struct *, int);
 
+#define UTRACE_FLAG(task, ev)  (task_utrace_flags(task) & UTRACE_EVENT(ev))
+
 #ifndef CONFIG_UTRACE
 
 /*
diff --git a/kernel/signal.c b/kernel/signal.c
index d7ef0da..0f9af0b 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -87,7 +87,7 @@ static int sig_ignored(struct task_struct *t, int sig, int 
from_ancestor_ns)
        /*
         * Tracers may want to know about even ignored signals.
         */
-       return !t->ptrace;
+       return !t->ptrace && !UTRACE_FLAG(t, SIGNAL_IGN);
 }
 
 /*
@@ -150,6 +150,11 @@ void recalc_sigpending_and_wake(struct task_struct *t)
 
 void recalc_sigpending(void)
 {
+       if (task_utrace_flags(current) && utrace_interrupt_pending()) {
+               set_thread_flag(TIF_SIGPENDING);
+               return;
+       }
+
        if (!recalc_sigpending_tsk(current) && !freezing(current))
                clear_thread_flag(TIF_SIGPENDING);
 
-- 
1.5.5.1