freebsd-src/sys/fs/procfs/procfs_status.c
John Baldwin 78c85e8dfc Rework how we store process times in the kernel such that we always store
the raw values including for child process statistics and only compute the
system and user timevals on demand.

- Fix the various kern_wait() syscall wrappers to only pass in a rusage
  pointer if they are going to use the result.
- Add a kern_getrusage() function for the ABI syscalls to use so that they
  don't have to play stackgap games to call getrusage().
- Fix the svr4_sys_times() syscall to just call calcru() to calculate the
  times it needs rather than calling getrusage() twice with associated
  stackgap, etc.
- Add a new rusage_ext structure to store raw time stats such as tick counts
  for user, system, and interrupt time as well as a bintime of the total
  runtime.  A new p_rux field in struct proc replaces the same inline fields
  from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime).  A new p_crux
  field in struct proc contains the "raw" child time usage statistics.
  ruadd() has been changed to handle adding the associated rusage_ext
  structures as well as the values in rusage.  Effectively, the values in
  rusage_ext replace the ru_utime and ru_stime values in struct rusage.  These
  two fields in struct rusage are no longer used in the kernel.
- calcru() has been split into a static worker function calcru1() that
  calculates appropriate timevals for user and system time as well as updating
  the rux_[isu]u fields of a passed in rusage_ext structure.  calcru() uses a
  copy of the process' p_rux structure to compute the timevals after updating
  the runtime appropriately if any of the threads in that process are
  currently executing.  It also now only locks sched_lock internally while
  doing the rux_runtime fixup.  calcru() now only requires the caller to
  hold the proc lock and calcru1() only requires the proc lock internally.
  calcru() also no longer allows callers to ask for an interrupt timeval
  since none of them actually did.
- calcru() now correctly handles threads executing on other CPUs.
- A new calccru() function computes the child system and user timevals by
  calling calcru1() on p_crux.  Note that this means that any code that wants
  child times must now call this function rather than reading from p_cru
  directly.  This function also requires the proc lock.
- This finishes the locking for rusage and friends so some of the Giant locks
  in exit1() and kern_wait() are now gone.
- The locking in ttyinfo() has been tweaked so that a shared lock of the
  proctree lock is used to protect the process group rather than the process
  group lock.  By holding this lock until the end of the function we now
  ensure that the process/thread that we pick to dump info about will no
  longer vanish while we are trying to output its info to the console.

Submitted by:	bde (mostly)
MFC after:	1 month
2004-10-05 18:51:11 +00:00

210 lines
5.6 KiB
C

/*
* Copyright (c) 1993 Jan-Simon Pendry
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)procfs_status.c 8.4 (Berkeley) 6/15/94
*
* From:
* $Id: procfs_status.c,v 3.1 1993/12/15 09:40:17 jsp Exp $
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/exec.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/jail.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sbuf.h>
#include <sys/sysent.h>
#include <sys/tty.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_param.h>
#include <fs/pseudofs/pseudofs.h>
#include <fs/procfs/procfs.h>
int
procfs_doprocstatus(PFS_FILL_ARGS)
{
struct session *sess;
struct thread *tdfirst;
struct tty *tp;
struct ucred *cr;
const char *wmesg;
char *pc;
char *sep;
int pid, ppid, pgid, sid;
int i;
pid = p->p_pid;
PROC_LOCK(p);
ppid = p->p_pptr ? p->p_pptr->p_pid : 0;
pgid = p->p_pgrp->pg_id;
sess = p->p_pgrp->pg_session;
SESS_LOCK(sess);
sid = sess->s_leader ? sess->s_leader->p_pid : 0;
/* comm pid ppid pgid sid maj,min ctty,sldr start ut st wmsg
euid ruid rgid,egid,groups[1 .. NGROUPS]
*/
pc = p->p_comm;
do {
if (*pc < 33 || *pc > 126 || *pc == '\\')
sbuf_printf(sb, "\\%03o", *pc);
else
sbuf_putc(sb, *pc);
} while (*++pc);
sbuf_printf(sb, " %d %d %d %d ", pid, ppid, pgid, sid);
if ((p->p_flag & P_CONTROLT) && (tp = sess->s_ttyp))
sbuf_printf(sb, "%d,%d ", major(tp->t_dev), minor(tp->t_dev));
else
sbuf_printf(sb, "%d,%d ", -1, -1);
sep = "";
if (sess->s_ttyvp) {
sbuf_printf(sb, "%sctty", sep);
sep = ",";
}
if (SESS_LEADER(p)) {
sbuf_printf(sb, "%ssldr", sep);
sep = ",";
}
SESS_UNLOCK(sess);
if (*sep != ',') {
sbuf_printf(sb, "noflags");
}
mtx_lock_spin(&sched_lock);
if (p->p_flag & P_SA)
wmesg = "-kse- ";
else {
tdfirst = FIRST_THREAD_IN_PROC(p);
if (tdfirst->td_wchan != NULL) {
KASSERT(tdfirst->td_wmesg != NULL,
("wchan %p has no wmesg", tdfirst->td_wchan));
wmesg = tdfirst->td_wmesg;
} else
wmesg = "nochan";
}
mtx_unlock_spin(&sched_lock);
if (p->p_sflag & PS_INMEM) {
struct timeval start, ut, st;
calcru(p, &ut, &st);
start = p->p_stats->p_start;
timevaladd(&start, &boottime);
sbuf_printf(sb, " %ld,%ld %ld,%ld %ld,%ld",
start.tv_sec, start.tv_usec,
ut.tv_sec, ut.tv_usec,
st.tv_sec, st.tv_usec);
} else {
sbuf_printf(sb, " -1,-1 -1,-1 -1,-1");
}
sbuf_printf(sb, " %s", wmesg);
cr = p->p_ucred;
sbuf_printf(sb, " %lu %lu %lu",
(u_long)cr->cr_uid,
(u_long)cr->cr_ruid,
(u_long)cr->cr_rgid);
/* egid (cr->cr_svgid) is equal to cr_ngroups[0]
see also getegid(2) in /sys/kern/kern_prot.c */
for (i = 0; i < cr->cr_ngroups; i++) {
sbuf_printf(sb, ",%lu", (u_long)cr->cr_groups[i]);
}
if (jailed(p->p_ucred)) {
mtx_lock(&p->p_ucred->cr_prison->pr_mtx);
sbuf_printf(sb, " %s", p->p_ucred->cr_prison->pr_host);
mtx_unlock(&p->p_ucred->cr_prison->pr_mtx);
} else {
sbuf_printf(sb, " -");
}
PROC_UNLOCK(p);
sbuf_printf(sb, "\n");
return (0);
}
int
procfs_doproccmdline(PFS_FILL_ARGS)
{
struct ps_strings pstr;
int error, i;
/*
* If we are using the ps/cmdline caching, use that. Otherwise
* revert back to the old way which only implements full cmdline
* for the currept process and just p->p_comm for all other
* processes.
* Note that if the argv is no longer available, we deliberately
* don't fall back on p->p_comm or return an error: the authentic
* Linux behaviour is to return zero-length in this case.
*/
PROC_LOCK(p);
if (p->p_args && p_cansee(td, p) == 0) {
sbuf_bcpy(sb, p->p_args->ar_args, p->p_args->ar_length);
PROC_UNLOCK(p);
return (0);
}
PROC_UNLOCK(p);
if (p != td->td_proc) {
sbuf_printf(sb, "%.*s", MAXCOMLEN, p->p_comm);
} else {
error = copyin((void *)p->p_sysent->sv_psstrings, &pstr,
sizeof(pstr));
if (error)
return (error);
for (i = 0; i < pstr.ps_nargvstr; i++) {
sbuf_copyin(sb, pstr.ps_argvstr[i], 0);
sbuf_printf(sb, "%c", '\0');
}
}
return (0);
}