Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759125Ab3DQTzJ (ORCPT ); Wed, 17 Apr 2013 15:55:09 -0400 Received: from terminus.zytor.com ([198.137.202.10]:58305 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758718Ab3DQTzE (ORCPT ); Wed, 17 Apr 2013 15:55:04 -0400 Date: Wed, 17 Apr 2013 12:54:52 -0700 From: tip-bot for Pavel Emelyanov Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, matt.helsley@gmail.com, peterz@infradead.org, xemul@parallels.com, tglx@linutronix.de, mtk.manpages@gmail.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, matt.helsley@gmail.com, peterz@infradead.org, xemul@parallels.com, tglx@linutronix.de, mtk.manpages@gmail.com In-Reply-To: <513DA00D.6070009@parallels.com> References: <513DA00D.6070009@parallels.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/core] posix-timers: Introduce /proc/PID/timers file Git-Commit-ID: 48f6a7a511ef8823fdff39afee0320092d43a8a0 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Wed, 17 Apr 2013 12:54:58 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4481 Lines: 152 Commit-ID: 48f6a7a511ef8823fdff39afee0320092d43a8a0 Gitweb: http://git.kernel.org/tip/48f6a7a511ef8823fdff39afee0320092d43a8a0 Author: Pavel Emelyanov AuthorDate: Mon, 11 Mar 2013 13:12:45 +0400 Committer: Thomas Gleixner CommitDate: Wed, 17 Apr 2013 20:51:01 +0200 posix-timers: Introduce /proc/PID/timers file Currently kernel doesn't provide any API for getting info about what posix timers are configured by processes. It's implied, that a process which configured some timers, knows what it did. However, for external tools it's impossible to get this information. In particular, this is critical for checkpoint-restore project to have this info. Introduce a per-pid proc file with information about posix timers. Since these timers are shared between threads, this file is present on tgid level only, no such thing in tid subdirs. The file format is expected to be the "/proc//smaps"-like, i.e. each timer will occupy seveal lines to allow for future extending. Each new timer entry starts with the ID: line which is added by this patch. Signed-off-by: Pavel Emelyanov Cc: Peter Zijlstra Cc: Michael Kerrisk Cc: Matthew Helsley Link: http://lkml.kernel.org/r/513DA00D.6070009@parallels.com Signed-off-by: Thomas Gleixner --- fs/proc/base.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) diff --git a/fs/proc/base.c b/fs/proc/base.c index 69078c7..01def9f 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -86,6 +86,7 @@ #include #include #include +#include #ifdef CONFIG_HARDWALL #include #endif @@ -2013,6 +2014,85 @@ static const struct file_operations proc_map_files_operations = { .llseek = default_llseek, }; +struct timers_private { + struct pid *pid; + struct task_struct *task; + struct sighand_struct *sighand; + unsigned long flags; +}; + +static void *timers_start(struct seq_file *m, loff_t *pos) +{ + struct timers_private *tp = m->private; + + tp->task = get_pid_task(tp->pid, PIDTYPE_PID); + if (!tp->task) + return ERR_PTR(-ESRCH); + + tp->sighand = lock_task_sighand(tp->task, &tp->flags); + if (!tp->sighand) + return ERR_PTR(-ESRCH); + + return seq_list_start(&tp->task->signal->posix_timers, *pos); +} + +static void *timers_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct timers_private *tp = m->private; + return seq_list_next(v, &tp->task->signal->posix_timers, pos); +} + +static void timers_stop(struct seq_file *m, void *v) +{ + struct timers_private *tp = m->private; + + if (tp->sighand) { + unlock_task_sighand(tp->task, &tp->flags); + tp->sighand = NULL; + } + + if (tp->task) { + put_task_struct(tp->task); + tp->task = NULL; + } +} + +static int show_timer(struct seq_file *m, void *v) +{ + struct k_itimer *timer; + + timer = list_entry((struct list_head *)v, struct k_itimer, list); + seq_printf(m, "ID: %d\n", timer->it_id); + + return 0; +} + +static const struct seq_operations proc_timers_seq_ops = { + .start = timers_start, + .next = timers_next, + .stop = timers_stop, + .show = show_timer, +}; + +static int proc_timers_open(struct inode *inode, struct file *file) +{ + struct timers_private *tp; + + tp = __seq_open_private(file, &proc_timers_seq_ops, + sizeof(struct timers_private)); + if (!tp) + return -ENOMEM; + + tp->pid = proc_pid(inode); + return 0; +} + +static const struct file_operations proc_timers_operations = { + .open = proc_timers_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, +}; #endif /* CONFIG_CHECKPOINT_RESTORE */ static struct dentry *proc_pident_instantiate(struct inode *dir, @@ -2583,6 +2663,9 @@ static const struct pid_entry tgid_base_stuff[] = { REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), #endif +#ifdef CONFIG_CHECKPOINT_RESTORE + REG("timers", S_IRUGO, proc_timers_operations), +#endif }; static int proc_tgid_base_readdir(struct file * filp, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/