taskstats.h

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/* taskstats.h - exporting per-task statistics
 *
 * Copyright (C) Shailabh Nagar, IBM Corp. 2006
 *           (C) Balbir Singh,   IBM Corp. 2006
 *           (C) Jay Lan,        SGI, 2006
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2.1 of the GNU Lesser General Public License
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef _LINUX_TASKSTATS_H
#define _LINUX_TASKSTATS_H

#include <linux/types.h>

/* Format for per-task data returned to userland when
 *  - a task exits
 *  - listener requests stats for a task
 *
 * The struct is versioned. Newer versions should only add fields to
 * the bottom of the struct to maintain backward compatibility.
 *
 *
 * To add new fields
 *  a) bump up TASKSTATS_VERSION
 *  b) add comment indicating new version number at end of struct
 *  c) add new fields after version comment; maintain 64-bit alignment
 */


#define TASKSTATS_VERSION   8
#define TS_COMM_LEN     32  /* should be >= TASK_COMM_LEN
                     * in linux/sched.h */

struct taskstats {

    /* The version number of this struct. This field is always set to
     * TAKSTATS_VERSION, which is defined in <linux/taskstats.h>.
     * Each time the struct is changed, the value should be incremented.
     */
    __u16   version;
    __u32   ac_exitcode;        /* Exit status */

    /* The accounting flags of a task as defined in <linux/acct.h>
     * Defined values are AFORK, ASU, ACOMPAT, ACORE, and AXSIG.
     */
    __u8    ac_flag;        /* Record flags */
    __u8    ac_nice;        /* task_nice */

    /* Delay accounting fields start
     *
     * All values, until comment "Delay accounting fields end" are
     * available only if delay accounting is enabled, even though the last
     * few fields are not delays
     *
     * xxx_count is the number of delay values recorded
     * xxx_delay_total is the corresponding cumulative delay in nanoseconds
     *
     * xxx_delay_total wraps around to zero on overflow
     * xxx_count incremented regardless of overflow
     */

    /* Delay waiting for cpu, while runnable
     * count, delay_total NOT updated atomically
     */
    __u64   cpu_count __attribute__((aligned(8)));
    __u64   cpu_delay_total;

    /* Following four fields atomically updated using task->delays->lock */

    /* Delay waiting for synchronous block I/O to complete
     * does not account for delays in I/O submission
     */
    __u64   blkio_count;
    __u64   blkio_delay_total;

    /* Delay waiting for page fault I/O (swap in only) */
    __u64   swapin_count;
    __u64   swapin_delay_total;

    /* cpu "wall-clock" running time
     * On some architectures, value will adjust for cpu time stolen
     * from the kernel in involuntary waits due to virtualization.
     * Value is cumulative, in nanoseconds, without a corresponding count
     * and wraps around to zero silently on overflow
     */
    __u64   cpu_run_real_total;

    /* cpu "virtual" running time
     * Uses time intervals seen by the kernel i.e. no adjustment
     * for kernel's involuntary waits due to virtualization.
     * Value is cumulative, in nanoseconds, without a corresponding count
     * and wraps around to zero silently on overflow
     */
    __u64   cpu_run_virtual_total;
    /* Delay accounting fields end */
    /* version 1 ends here */

    /* Basic Accounting Fields start */
    char    ac_comm[TS_COMM_LEN];   /* Command name */
    __u8    ac_sched __attribute__((aligned(8)));
                    /* Scheduling discipline */
    __u8    ac_pad[3];
    __u32   ac_uid __attribute__((aligned(8)));
                    /* User ID */
    __u32   ac_gid;         /* Group ID */
    __u32   ac_pid;         /* Process ID */
    __u32   ac_ppid;        /* Parent process ID */
    __u32   ac_btime;       /* Begin time [sec since 1970] */
    __u64   ac_etime __attribute__((aligned(8)));
                    /* Elapsed time [usec] */
    __u64   ac_utime;       /* User CPU time [usec] */
    __u64   ac_stime;       /* SYstem CPU time [usec] */
    __u64   ac_minflt;      /* Minor Page Fault Count */
    __u64   ac_majflt;      /* Major Page Fault Count */
    /* Basic Accounting Fields end */

    /* Extended accounting fields start */
    /* Accumulated RSS usage in duration of a task, in MBytes-usecs.
     * The current rss usage is added to this counter every time
     * a tick is charged to a task's system time. So, at the end we
     * will have memory usage multiplied by system time. Thus an
     * average usage per system time unit can be calculated.
     */
    __u64   coremem;        /* accumulated RSS usage in MB-usec */
    /* Accumulated virtual memory usage in duration of a task.
     * Same as acct_rss_mem1 above except that we keep track of VM usage.
     */
    __u64   virtmem;        /* accumulated VM  usage in MB-usec */

    /* High watermark of RSS and virtual memory usage in duration of
     * a task, in KBytes.
     */
    __u64   hiwater_rss;        /* High-watermark of RSS usage, in KB */
    __u64   hiwater_vm;     /* High-water VM usage, in KB */

    /* The following four fields are I/O statistics of a task. */
    __u64   read_char;      /* bytes read */
    __u64   write_char;     /* bytes written */
    __u64   read_syscalls;      /* read syscalls */
    __u64   write_syscalls;     /* write syscalls */
    /* Extended accounting fields end */

#define TASKSTATS_HAS_IO_ACCOUNTING
    /* Per-task storage I/O accounting starts */
    __u64   read_bytes;     /* bytes of read I/O */
    __u64   write_bytes;        /* bytes of write I/O */
    __u64   cancelled_write_bytes;  /* bytes of cancelled write I/O */

    __u64  nvcsw;           /* voluntary_ctxt_switches */
    __u64  nivcsw;          /* nonvoluntary_ctxt_switches */

    /* time accounting for SMT machines */
    __u64   ac_utimescaled;     /* utime scaled on frequency etc */
    __u64   ac_stimescaled;     /* stime scaled on frequency etc */
    __u64   cpu_scaled_run_real_total; /* scaled cpu_run_real_total */

    /* Delay waiting for memory reclaim */
    __u64   freepages_count;
    __u64   freepages_delay_total;
};


/*
 * Commands sent from userspace
 * Not versioned. New commands should only be inserted at the enum's end
 * prior to __TASKSTATS_CMD_MAX
 */

enum {
    TASKSTATS_CMD_UNSPEC = 0,   /* Reserved */
    TASKSTATS_CMD_GET,      /* user->kernel request/get-response */
    TASKSTATS_CMD_NEW,      /* kernel->user event */
    __TASKSTATS_CMD_MAX,
};

#define TASKSTATS_CMD_MAX (__TASKSTATS_CMD_MAX - 1)

enum {
    TASKSTATS_TYPE_UNSPEC = 0,  /* Reserved */
    TASKSTATS_TYPE_PID,     /* Process id */
    TASKSTATS_TYPE_TGID,        /* Thread group id */
    TASKSTATS_TYPE_STATS,       /* taskstats structure */
    TASKSTATS_TYPE_AGGR_PID,    /* contains pid + stats */
    TASKSTATS_TYPE_AGGR_TGID,   /* contains tgid + stats */
    TASKSTATS_TYPE_NULL,        /* contains nothing */
    __TASKSTATS_TYPE_MAX,
};

#define TASKSTATS_TYPE_MAX (__TASKSTATS_TYPE_MAX - 1)

enum {
    TASKSTATS_CMD_ATTR_UNSPEC = 0,
    TASKSTATS_CMD_ATTR_PID,
    TASKSTATS_CMD_ATTR_TGID,
    TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
    TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
    __TASKSTATS_CMD_ATTR_MAX,
};

#define TASKSTATS_CMD_ATTR_MAX (__TASKSTATS_CMD_ATTR_MAX - 1)

/* NETLINK_GENERIC related info */

#define TASKSTATS_GENL_NAME "TASKSTATS"
#define TASKSTATS_GENL_VERSION  0x1

#endif /* _LINUX_TASKSTATS_H */