From patchwork Wed Sep 21 19:26:44 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 115844 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id DB1BD1007D3 for ; Thu, 22 Sep 2011 05:27:04 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751770Ab1IUT1A (ORCPT ); Wed, 21 Sep 2011 15:27:00 -0400 Received: from smtp-out.google.com ([74.125.121.67]:57022 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751584Ab1IUT07 (ORCPT ); Wed, 21 Sep 2011 15:26:59 -0400 Received: from hpaq6.eem.corp.google.com (hpaq6.eem.corp.google.com [172.25.149.6]) by smtp-out.google.com with ESMTP id p8LJQn3Z027940; Wed, 21 Sep 2011 12:26:49 -0700 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=google.com; s=beta; t=1316633209; bh=WPAnglQ1eA/2CC6i4M0G48ivles=; h=Message-Id:Subject:To:Cc:From:Date:MIME-Version:Content-Type: Content-Transfer-Encoding; b=LS7piaHICWHIB6S/ehZSqt66UieCt3mD9LLwFdBt2ZssaOhRPp2cvxdLsGytosoJ8 nbPiHJvdAKcS80MhXa7cQ== DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=message-id:subject:to:cc:from:date:mime-version: content-type:content-transfer-encoding; b=BEBjzuVkehfg7HTbJmevUNcOjaZrLAsiIBOmsIn5YrtMeUbK9jN4+LpwYKtCcrkb7 Wc39z8Hi+NqGfG54vzCsg== Received: from localhost.localdomain (akpm.mtv.corp.google.com [172.18.96.75]) by hpaq6.eem.corp.google.com with ESMTP id p8LJQk0P007038; Wed, 21 Sep 2011 12:26:46 -0700 Message-Id: <201109211926.p8LJQk0P007038@hpaq6.eem.corp.google.com> Subject: [patch 1/1] connector: add comm change event report to proc connector To: davem@davemloft.net Cc: netdev@vger.kernel.org, akpm@google.com, vzapolskiy@gmail.com, zbr@ioremap.net From: akpm@google.com Date: Wed, 21 Sep 2011 12:26:44 -0700 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vladimir Zapolskiy Subject: connector: add comm change event report to proc connector Add an event to monitor comm value changes of tasks. Such an event becomes vital, if someone desires to control threads of a process in different manner. A natural characteristic of threads is its comm value, and helpfully application developers have an opportunity to change it in runtime. Reporting about such events via proc connector allows to fine-grain monitoring and control potentials, for instance a process control daemon listening to proc connector and following comm value policies can place specific threads to assigned cgroup partitions. It might be possible to achieve a pale partial one-shot likeness without this update, if an application changes comm value of a thread generator task beforehand, then a new thread is cloned, and after that proc connector listener gets the fork event and reads new thread's comm value from procfs stat file, but this change visibly simplifies and extends the matter. Signed-off-by: Vladimir Zapolskiy Acked-by: Evgeniy Polyakov Cc: David Miller Signed-off-by: Andrew Morton --- drivers/connector/cn_proc.c | 26 ++++++++++++++++++++++++++ include/linux/cn_proc.h | 11 +++++++++++ kernel/sys.c | 1 + 3 files changed, 38 insertions(+) diff -puN drivers/connector/cn_proc.c~connector-add-comm-change-event-report-to-proc-connector drivers/connector/cn_proc.c --- a/drivers/connector/cn_proc.c~connector-add-comm-change-event-report-to-proc-connector +++ a/drivers/connector/cn_proc.c @@ -205,6 +205,32 @@ void proc_ptrace_connector(struct task_s cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); } +void proc_comm_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + struct timespec ts; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg *)buffer; + ev = (struct proc_event *)msg->data; + get_seq(&msg->seq, &ev->cpu); + ktime_get_ts(&ts); /* get high res monotonic timestamp */ + put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); + ev->what = PROC_EVENT_COMM; + ev->event_data.comm.process_pid = task->pid; + ev->event_data.comm.process_tgid = task->tgid; + get_task_comm(ev->event_data.comm.comm, task); + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + void proc_exit_connector(struct task_struct *task) { struct cn_msg *msg; diff -puN include/linux/cn_proc.h~connector-add-comm-change-event-report-to-proc-connector include/linux/cn_proc.h --- a/include/linux/cn_proc.h~connector-add-comm-change-event-report-to-proc-connector +++ a/include/linux/cn_proc.h @@ -54,6 +54,7 @@ struct proc_event { PROC_EVENT_GID = 0x00000040, PROC_EVENT_SID = 0x00000080, PROC_EVENT_PTRACE = 0x00000100, + PROC_EVENT_COMM = 0x00000200, /* "next" should be 0x00000400 */ /* "last" is the last process event: exit */ PROC_EVENT_EXIT = 0x80000000 @@ -103,6 +104,12 @@ struct proc_event { __kernel_pid_t tracer_tgid; } ptrace; + struct comm_proc_event { + __kernel_pid_t process_pid; + __kernel_pid_t process_tgid; + char comm[16]; + } comm; + struct exit_proc_event { __kernel_pid_t process_pid; __kernel_pid_t process_tgid; @@ -118,6 +125,7 @@ void proc_exec_connector(struct task_str void proc_id_connector(struct task_struct *task, int which_id); void proc_sid_connector(struct task_struct *task); void proc_ptrace_connector(struct task_struct *task, int which_id); +void proc_comm_connector(struct task_struct *task); void proc_exit_connector(struct task_struct *task); #else static inline void proc_fork_connector(struct task_struct *task) @@ -133,6 +141,9 @@ static inline void proc_id_connector(str static inline void proc_sid_connector(struct task_struct *task) {} +static inline void proc_comm_connector(struct task_struct *task) +{} + static inline void proc_ptrace_connector(struct task_struct *task, int ptrace_id) {} diff -puN kernel/sys.c~connector-add-comm-change-event-report-to-proc-connector kernel/sys.c --- a/kernel/sys.c~connector-add-comm-change-event-report-to-proc-connector +++ a/kernel/sys.c @@ -1760,6 +1760,7 @@ SYSCALL_DEFINE5(prctl, int, option, unsi sizeof(me->comm) - 1) < 0) return -EFAULT; set_task_comm(me, comm); + proc_comm_connector(me); return 0; case PR_GET_NAME: get_task_comm(comm, me);