From: Tejun Heo <tj@kernel.org>
To: oleg@redhat.com, jan.kratochvil@redhat.com, vda.linux@googlemail.com
Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
akpm@linux-foundation.org, indan@nul.nu, roland@hack.frob.com,
Tejun Heo <tj@kernel.org>
Subject: [PATCH 11/20] ptrace: Collapse ptrace_untrace() into __ptrace_unlink()
Date: Wed, 23 Mar 2011 11:05:57 +0100 [thread overview]
Message-ID: <1300874766-12941-12-git-send-email-tj@kernel.org> (raw)
In-Reply-To: <1300874766-12941-1-git-send-email-tj@kernel.org>
Remove the extra task_is_traced() check in __ptrace_unlink() and
collapse ptrace_untrace() into __ptrace_unlink(). This is to prepare
for further changes.
While at it, drop the comment on top of ptrace_untrace() and convert
__ptrace_unlink() comment to docbook format. Detailed comment will be
added by the next patch.
This patch doesn't cause any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
---
kernel/ptrace.c | 40 +++++++++++++++-------------------------
1 files changed, 15 insertions(+), 25 deletions(-)
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 745fc2d..e609843 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -37,15 +37,23 @@ void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
child->parent = new_parent;
}
-/*
- * Turn a tracing stop into a normal stop now, since with no tracer there
- * would be no way to wake it up with SIGCONT or SIGKILL. If there was a
- * signal sent that would resume the child, but didn't because it was in
- * TASK_TRACED, resume it now.
- * Requires that irqs be disabled.
+/**
+ * __ptrace_unlink - unlink ptracee and restore its execution state
+ * @child: ptracee to be unlinked
+ *
+ * Remove @child from the ptrace list, move it back to the original parent.
+ *
+ * CONTEXT:
+ * write_lock_irq(tasklist_lock)
*/
-static void ptrace_untrace(struct task_struct *child)
+void __ptrace_unlink(struct task_struct *child)
{
+ BUG_ON(!child->ptrace);
+
+ child->ptrace = 0;
+ child->parent = child->real_parent;
+ list_del_init(&child->ptrace_entry);
+
spin_lock(&child->sighand->siglock);
if (task_is_traced(child)) {
/*
@@ -70,24 +78,6 @@ static void ptrace_untrace(struct task_struct *child)
}
/*
- * unptrace a task: move it back to its original parent and
- * remove it from the ptrace list.
- *
- * Must be called with the tasklist lock write-held.
- */
-void __ptrace_unlink(struct task_struct *child)
-{
- BUG_ON(!child->ptrace);
-
- child->ptrace = 0;
- child->parent = child->real_parent;
- list_del_init(&child->ptrace_entry);
-
- if (task_is_traced(child))
- ptrace_untrace(child);
-}
-
-/*
* Check that we have indeed attached to the thing..
*/
int ptrace_check_attach(struct task_struct *child, int kill)
--
1.7.1
next prev parent reply other threads:[~2011-03-23 10:09 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-23 10:05 [PATCHSET] ptrace,signal: Improve ptrace and job control interaction Tejun Heo
2011-03-23 10:05 ` [PATCH 01/20] signal: Fix SIGCONT notification code Tejun Heo
2011-03-23 10:05 ` [PATCH 02/20] ptrace: Remove the extra wake_up_state() from ptrace_detach() Tejun Heo
2011-03-23 10:05 ` [PATCH 03/20] signal: Remove superflous try_to_freeze() loop in do_signal_stop() Tejun Heo
2011-03-23 10:05 ` [PATCH 04/20] ptrace: Kill tracehook_notify_jctl() Tejun Heo
2011-03-23 10:05 ` [PATCH 05/20] ptrace: Add @why to ptrace_stop() Tejun Heo
2011-03-23 10:05 ` [PATCH 06/20] signal: Fix premature completion of group stop when interfered by ptrace Tejun Heo
2011-03-23 10:05 ` [PATCH 07/20] signal: Use GROUP_STOP_PENDING to stop once for a single group stop Tejun Heo
2011-03-23 10:05 ` [PATCH 08/20] ptrace: Participate in group stop from ptrace_stop() iff the task is trapping for " Tejun Heo
2011-03-23 10:05 ` [PATCH 09/20] ptrace: Make do_signal_stop() use ptrace_stop() if the task is being ptraced Tejun Heo
2011-03-23 10:05 ` [PATCH 10/20] ptrace: Clean transitions between TASK_STOPPED and TRACED Tejun Heo
2011-03-23 10:05 ` Tejun Heo [this message]
2011-03-23 10:05 ` [PATCH 12/20] ptrace: Always put ptracee into appropriate execution state Tejun Heo
2011-03-23 10:05 ` [PATCH 13/20] job control: Don't set group_stop exit_code if re-entering job control stop Tejun Heo
2011-03-23 10:06 ` [PATCH 14/20] job control: Small reorganization of wait_consider_task() Tejun Heo
2011-03-23 10:06 ` [PATCH 15/20] job control: Fix ptracer wait(2) hang and explain notask_error clearing Tejun Heo
2011-03-23 10:06 ` [PATCH 16/20] job control: Allow access to job control events through ptracees Tejun Heo
2011-03-23 10:06 ` [PATCH 17/20] job control: Add @for_ptrace to do_notify_parent_cldstop() Tejun Heo
2011-03-23 10:06 ` [PATCH 18/20] job control: Job control stop notifications should always go to the real parent Tejun Heo
2011-03-23 10:06 ` [PATCH 19/20] job control: Notify the real parent of job control events regardless of ptrace Tejun Heo
2011-03-23 10:06 ` [PATCH 20/20] job control: Don't send duplicate job control stop notification while ptraced Tejun Heo
2011-03-23 18:38 ` [PATCHSET] ptrace,signal: Improve ptrace and job control interaction Oleg Nesterov
2011-03-25 14:26 ` Tejun Heo
2011-03-26 18:25 ` Oleg Nesterov
2011-03-28 8:58 ` Tejun Heo
2011-03-28 12:14 ` Oleg Nesterov
2011-03-28 15:21 ` Tejun Heo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1300874766-12941-12-git-send-email-tj@kernel.org \
--to=tj@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=indan@nul.nu \
--cc=jan.kratochvil@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=oleg@redhat.com \
--cc=roland@hack.frob.com \
--cc=torvalds@linux-foundation.org \
--cc=vda.linux@googlemail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).