The patch titled
ITIMER_REAL: convert to use struct pid
has been added to the -mm tree. Its filename is
itimer_real-convert-to-use-struct-pid.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: ITIMER_REAL: convert to use struct pid
From: Oleg Nesterov <oleg@xxxxxxxxxx>
signal_struct->tsk points to the ->group_leader and thus we have the nasty
code in de_thread() which has to change it and restart ->real_timer if the
leader is changed.
Use "struct pid *leader_pid" instead. This also allows us to kill now
unneeded send_group_sig_info().
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: Davide Libenzi <davidel@xxxxxxxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxx>
Acked-by: Roland McGrath <roland@xxxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/exec.c | 22 ++--------------------
include/linux/sched.h | 3 +--
kernel/fork.c | 2 +-
kernel/itimer.c | 2 +-
kernel/signal.c | 14 --------------
5 files changed, 5 insertions(+), 38 deletions(-)
diff -puN fs/exec.c~itimer_real-convert-to-use-struct-pid fs/exec.c
--- a/fs/exec.c~itimer_real-convert-to-use-struct-pid
+++ a/fs/exec.c
@@ -782,26 +782,8 @@ static int de_thread(struct task_struct
zap_other_threads(tsk);
read_unlock(&tasklist_lock);
- /*
- * Account for the thread group leader hanging around:
- */
- count = 1;
- if (!thread_group_leader(tsk)) {
- count = 2;
- /*
- * The SIGALRM timer survives the exec, but needs to point
- * at us as the new group leader now. We have a race with
- * a timer firing now getting the old leader, so we need to
- * synchronize with any firing (by calling del_timer_sync)
- * before we can safely let the old group leader die.
- */
- sig->tsk = tsk;
- spin_unlock_irq(lock);
- if (hrtimer_cancel(&sig->real_timer))
- hrtimer_restart(&sig->real_timer);
- spin_lock_irq(lock);
- }
-
+ /* Account for the thread group leader hanging around: */
+ count = thread_group_leader(tsk) ? 1 : 2;
sig->notify_count = count;
while (atomic_read(&sig->count) > count) {
__set_current_state(TASK_UNINTERRUPTIBLE);
diff -puN include/linux/sched.h~itimer_real-convert-to-use-struct-pid include/linux/sched.h
--- a/include/linux/sched.h~itimer_real-convert-to-use-struct-pid
+++ a/include/linux/sched.h
@@ -453,7 +453,7 @@ struct signal_struct {
/* ITIMER_REAL timer for the process */
struct hrtimer real_timer;
- struct task_struct *tsk;
+ struct pid *leader_pid;
ktime_t it_real_incr;
/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
@@ -1663,7 +1663,6 @@ extern void block_all_signals(int (*noti
extern void unblock_all_signals(void);
extern void release_task(struct task_struct * p);
extern int send_sig_info(int, struct siginfo *, struct task_struct *);
-extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
extern int force_sigsegv(int, struct task_struct *);
extern int force_sig_info(int, struct siginfo *, struct task_struct *);
extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
diff -puN kernel/fork.c~itimer_real-convert-to-use-struct-pid kernel/fork.c
--- a/kernel/fork.c~itimer_real-convert-to-use-struct-pid
+++ a/kernel/fork.c
@@ -883,7 +883,6 @@ static int copy_signal(unsigned long clo
hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
sig->it_real_incr.tv64 = 0;
sig->real_timer.function = it_real_fn;
- sig->tsk = tsk;
sig->it_virt_expires = cputime_zero;
sig->it_virt_incr = cputime_zero;
@@ -1308,6 +1307,7 @@ static struct task_struct *copy_process(
if (clone_flags & CLONE_NEWPID)
p->nsproxy->pid_ns->child_reaper = p;
+ p->signal->leader_pid = pid;
p->signal->tty = current->signal->tty;
set_task_pgrp(p, task_pgrp_nr(current));
set_task_session(p, task_session_nr(current));
diff -puN kernel/itimer.c~itimer_real-convert-to-use-struct-pid kernel/itimer.c
--- a/kernel/itimer.c~itimer_real-convert-to-use-struct-pid
+++ a/kernel/itimer.c
@@ -132,7 +132,7 @@ enum hrtimer_restart it_real_fn(struct h
struct signal_struct *sig =
container_of(timer, struct signal_struct, real_timer);
- send_group_sig_info(SIGALRM, SEND_SIG_PRIV, sig->tsk);
+ kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid);
return HRTIMER_NORESTART;
}
diff -puN kernel/signal.c~itimer_real-convert-to-use-struct-pid kernel/signal.c
--- a/kernel/signal.c~itimer_real-convert-to-use-struct-pid
+++ a/kernel/signal.c
@@ -1204,20 +1204,6 @@ send_sig(int sig, struct task_struct *p,
return send_sig_info(sig, __si_special(priv), p);
}
-/*
- * This is the entry point for "process-wide" signals.
- * They will go to an appropriate thread in the thread group.
- */
-int
-send_group_sig_info(int sig, struct siginfo *info, struct task_struct *p)
-{
- int ret;
- read_lock(&tasklist_lock);
- ret = group_send_sig_info(sig, info, p);
- read_unlock(&tasklist_lock);
- return ret;
-}
-
void
force_sig(int sig, struct task_struct *p)
{
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
__group_complete_signal-fix-coredump-with-group-stop-race.patch
remove-handle_group_stop-in-favor-of-do_signal_stop.patch
exec-rework-the-group-exit-and-fix-the-race-with-kill.patch
use-__set_task_state-for-traced-stopped-tasks.patch
add-task_wakekill.patch
do_wait-remove-one-else-if-branch.patch
proc-implement-proc_single_file_operations.patch
proc-rewrite-do_task_stat-to-correctly-handle-pid-namespaces.patch
proc-seqfile-convert-proc_pid_statm.patch
proc-proper-pidns-handling-for-proc-self.patch
proc-fix-the-threaded-proc-self.patch
kill-pt_attached.patch
kill-my_ptrace_child.patch
ptrace_check_attach-remove-unneeded-signal-=-null-check.patch
ptrace_stop-fix-the-race-with-ptrace-detachattach.patch
wait_task_stopped-simplify-and-fix-races-with-sigcont-sigkill-untrace.patch
do_wait-factor-out-retval-=-0-checks.patch
ptrace_stop-fix-racy-nonstop_code-setting.patch
wait_task_stopped-remove-unneeded-delay_group_leader-check.patch
do_wait-cleanup-delay_group_leader-usage.patch
do_wait-fix-security-checks.patch
do_wait-fix-security-checks-fix.patch
wait_task_continued-zombie-dont-use-task_pid_nr_ns-lockless.patch
wait_task_zombie-remove-exit_state-exit_signal-checks-for-wnowait.patch
sys_setpgid-simplify-pid-ns-interaction.patch
fix-setsid-for-sub-namespace-sbin-init.patch
teach-set_special_pids-to-use-struct-pid.patch
move-daemonized-kernel-threads-into-the-swappers-session.patch
start-the-global-sbin-init-with-00-special-pids.patch
fix-group-stop-with-exit-race.patch
sys_setsid-remove-now-unneeded-session-=-1-check.patch
move-the-related-code-from-exit_notify-to-exit_signals.patch
pid-sys_wait-fixes-v2.patch
pid-extend-fix-pid_vnr.patch
sys_getsid-dont-use-nsproxy-directly.patch
pid-fix-mips-irix-emulation-pid-usage.patch
pid-fix-solaris_procids.patch
uglify-kill_pid_info-to-fix-kill-vs-exec-race.patch
uglify-while_each_pid_task-to-make-sure-we-dont-count-the-execing-pricess-twice.patch
itimer_real-convert-to-use-struct-pid.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
