aha/include/linux/taskstats.h
Balbir Singh 7e40f2ab0a Taskstats fix the structure members alignment issue
We broke the the alignment of members of taskstats to the 8 byte boundary
with the CSA patches.  In the current kernel, the taskstats structure is
not suitable for use by 32 bit applications in a 64 bit kernel.

On x86_64

Offsets of taskstats' members (64 bit kernel, 64 bit application)

@taskstats'offsetof[@taskstats'indices] = (
        0,      # version
        4,      # ac_exitcode
        8,      # ac_flag
        9,      # ac_nice
        16,     # cpu_count
        24,     # cpu_delay_total
        32,     # blkio_count
        40,     # blkio_delay_total
        48,     # swapin_count
        56,     # swapin_delay_total
        64,     # cpu_run_real_total
        72,     # cpu_run_virtual_total
        80,     # ac_comm
        112,    # ac_sched
        113,    # ac_pad
        116,    # ac_uid
        120,    # ac_gid
        124,    # ac_pid
        128,    # ac_ppid
        132,    # ac_btime
        136,    # ac_etime
        144,    # ac_utime
        152,    # ac_stime
        160,    # ac_minflt
        168,    # ac_majflt
        176,    # coremem
        184,    # virtmem
        192,    # hiwater_rss
        200,    # hiwater_vm
        208,    # read_char
        216,    # write_char
        224,    # read_syscalls
        232,    # write_syscalls
        240,    # read_bytes
        248,    # write_bytes
        256,    # cancelled_write_bytes
    );

Offsets of taskstats' members (64 bit kernel, 32 bit application)

@taskstats'offsetof[@taskstats'indices] = (
        0,      # version
        4,      # ac_exitcode
        8,      # ac_flag
        9,      # ac_nice
        12,     # cpu_count
        20,     # cpu_delay_total
        28,     # blkio_count
        36,     # blkio_delay_total
        44,     # swapin_count
        52,     # swapin_delay_total
        60,     # cpu_run_real_total
        68,     # cpu_run_virtual_total
        76,     # ac_comm
        108,    # ac_sched
        109,    # ac_pad
        112,    # ac_uid
        116,    # ac_gid
        120,    # ac_pid
        124,    # ac_ppid
        128,    # ac_btime
        132,    # ac_etime
        140,    # ac_utime
        148,    # ac_stime
        156,    # ac_minflt
        164,    # ac_majflt
        172,    # coremem
        180,    # virtmem
        188,    # hiwater_rss
        196,    # hiwater_vm
        204,    # read_char
        212,    # write_char
        220,    # read_syscalls
        228,    # write_syscalls
        236,    # read_bytes
        244,    # write_bytes
        252,    # cancelled_write_bytes
    );

This is one way to solve the problem without re-arranging structure members
is to pack the structure.  The patch adds an __attribute__((aligned(8))) to
the taskstats structure members so that 32 bit applications using taskstats
can work with a 64 bit kernel.

Using __attribute__((packed)) would break the 64 bit alignment of members.

The fix was tested on x86_64. After the fix, we got

Offsets of taskstats' members (64 bit kernel, 64 bit application)

@taskstats'offsetof[@taskstats'indices] = (
        0,      # version
        4,      # ac_exitcode
        8,      # ac_flag
        9,      # ac_nice
        16,     # cpu_count
        24,     # cpu_delay_total
        32,     # blkio_count
        40,     # blkio_delay_total
        48,     # swapin_count
        56,     # swapin_delay_total
        64,     # cpu_run_real_total
        72,     # cpu_run_virtual_total
        80,     # ac_comm
        112,    # ac_sched
        113,    # ac_pad
        120,    # ac_uid
        124,    # ac_gid
        128,    # ac_pid
        132,    # ac_ppid
        136,    # ac_btime
        144,    # ac_etime
        152,    # ac_utime
        160,    # ac_stime
        168,    # ac_minflt
        176,    # ac_majflt
        184,    # coremem
        192,    # virtmem
        200,    # hiwater_rss
        208,    # hiwater_vm
        216,    # read_char
        224,    # write_char
        232,    # read_syscalls
        240,    # write_syscalls
        248,    # read_bytes
        256,    # write_bytes
        264,    # cancelled_write_bytes
    );

Offsets of taskstats' members (64 bit kernel, 32 bit application)

@taskstats'offsetof[@taskstats'indices] = (
        0,      # version
        4,      # ac_exitcode
        8,      # ac_flag
        9,      # ac_nice
        16,     # cpu_count
        24,     # cpu_delay_total
        32,     # blkio_count
        40,     # blkio_delay_total
        48,     # swapin_count
        56,     # swapin_delay_total
        64,     # cpu_run_real_total
        72,     # cpu_run_virtual_total
        80,     # ac_comm
        112,    # ac_sched
        113,    # ac_pad
        120,    # ac_uid
        124,    # ac_gid
        128,    # ac_pid
        132,    # ac_ppid
        136,    # ac_btime
        144,    # ac_etime
        152,    # ac_utime
        160,    # ac_stime
        168,    # ac_minflt
        176,    # ac_majflt
        184,    # coremem
        192,    # virtmem
        200,    # hiwater_rss
        208,    # hiwater_vm
        216,    # read_char
        224,    # write_char
        232,    # read_syscalls
        240,    # write_syscalls
        248,    # read_bytes
        256,    # write_bytes
        264,    # cancelled_write_bytes
    );

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-24 08:23:08 -07:00

198 lines
6.3 KiB
C

/* 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
/* 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 4
#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 */
};
/*
* 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_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 */