Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964938AbVLFCaH (ORCPT ); Mon, 5 Dec 2005 21:30:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964939AbVLFCaG (ORCPT ); Mon, 5 Dec 2005 21:30:06 -0500 Received: from e3.ny.us.ibm.com ([32.97.182.143]:59520 "EHLO e3.ny.us.ibm.com") by vger.kernel.org with ESMTP id S964938AbVLFCaE (ORCPT ); Mon, 5 Dec 2005 21:30:04 -0500 Subject: [RFC][PATCH] Add timestamp to process event connector message From: Matt Helsley To: LKML Cc: Andrew Morton , Jean-Pierre Dion , Guillaume Thouvenin , Badari Pulavarty , Ram Pai , CKRM-Tech , Erich Focht , elsa-devel , ay Lan , Erik Jacobson , Jack Steiner Content-Type: text/plain Date: Mon, 05 Dec 2005 18:21:57 -0800 Message-Id: <1133835717.25202.1317.camel@stark> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4673 Lines: 144 This patch adds a timestamp field to the events sent via the process event connector. The timestamp allows listeners to accurately account the duration(s) between a process' events and offers strong means with which to determine the order of events while also avoiding the addition of per-task data. This alters the size and layout of the event structure and hence would break compatibility if process events connector as it stands in 2.6.15-rc5 were released as a mainline kernel. Signed-off-by: Matt Helsley -- Index: linux-2.6.15-rc5/drivers/connector/cn_proc.c =================================================================== --- linux-2.6.15-rc5.orig/drivers/connector/cn_proc.c +++ linux-2.6.15-rc5/drivers/connector/cn_proc.c @@ -42,10 +42,31 @@ static inline void get_seq(__u32 *ts, in *ts = get_cpu_var(proc_event_counts)++; *cpu = smp_processor_id(); put_cpu_var(proc_event_counts); } +static inline void get_timestamp(struct timespec *ts) +{ + unsigned int seq; + struct timespec wall2mono; + + /* synchronize with settimeofday() changes */ + do { + seq = read_seqbegin(&xtime_lock); + getnstimeofday(ts); + wall2mono = wall_to_monotonic; + } while(read_seqretry(&xtime_lock, seq)); + + /* adjust to monotonicaly-increasing values */ + ts += wall2mono.tv_sec; + ts += wall2mono.tv_nsec; + while ((ts->tv_nsec - NSEC_PER_SEC) >= 0) { + ts->tv_nsec -= NSEC_PER_SEC; + ts->tv_sec++; + } +} + void proc_fork_connector(struct task_struct *task) { struct cn_msg *msg; struct proc_event *ev; __u8 buffer[CN_PROC_MSG_SIZE]; @@ -54,10 +75,11 @@ void proc_fork_connector(struct task_str return; msg = (struct cn_msg*)buffer; ev = (struct proc_event*)msg->data; get_seq(&msg->seq, &ev->cpu); + get_timestamp(&ev->timestamp); ev->what = PROC_EVENT_FORK; ev->event_data.fork.parent_pid = task->real_parent->pid; ev->event_data.fork.parent_tgid = task->real_parent->tgid; ev->event_data.fork.child_pid = task->pid; ev->event_data.fork.child_tgid = task->tgid; @@ -79,10 +101,11 @@ void proc_exec_connector(struct task_str return; msg = (struct cn_msg*)buffer; ev = (struct proc_event*)msg->data; get_seq(&msg->seq, &ev->cpu); + get_timestamp(&ev->timestamp); ev->what = PROC_EVENT_EXEC; ev->event_data.exec.process_pid = task->pid; ev->event_data.exec.process_tgid = task->tgid; memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); @@ -112,10 +135,11 @@ void proc_id_connector(struct task_struc ev->event_data.id.r.rgid = task->gid; ev->event_data.id.e.egid = task->egid; } else return; get_seq(&msg->seq, &ev->cpu); + get_timestamp(&ev->timestamp); 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); @@ -131,10 +155,11 @@ void proc_exit_connector(struct task_str return; msg = (struct cn_msg*)buffer; ev = (struct proc_event*)msg->data; get_seq(&msg->seq, &ev->cpu); + get_timestamp(&ev->timestamp); ev->what = PROC_EVENT_EXIT; ev->event_data.exit.process_pid = task->pid; ev->event_data.exit.process_tgid = task->tgid; ev->event_data.exit.exit_code = task->exit_code; ev->event_data.exit.exit_signal = task->exit_signal; @@ -163,10 +188,11 @@ static void cn_proc_ack(int err, int rcv return; msg = (struct cn_msg*)buffer; ev = (struct proc_event*)msg->data; msg->seq = rcvd_seq; + get_timestamp(&ev->timestamp); ev->cpu = -1; ev->what = PROC_EVENT_NONE; ev->event_data.ack.err = err; memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); msg->ack = rcvd_ack + 1; Index: linux-2.6.15-rc5/include/linux/cn_proc.h =================================================================== --- linux-2.6.15-rc5.orig/include/linux/cn_proc.h +++ linux-2.6.15-rc5/include/linux/cn_proc.h @@ -24,10 +24,11 @@ #ifndef CN_PROC_H #define CN_PROC_H #include +#include #include /* * Userspace sends this enum to register with the kernel that it is listening * for events on the connector. @@ -63,10 +64,11 @@ struct proc_event { /* "next" should be 0x00000400 */ /* "last" is the last process event: exit */ PROC_EVENT_EXIT = 0x80000000 } what; __u32 cpu; + struct timespec timestamp; union { /* must be last field of proc_event struct */ struct { __u32 err; } ack; - 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/