sysctls exporting swap information. When running on a live kernel,
the sysctl's will now be used instead of kvm_read, allowing consumers of
this interface to run without privilege (setgid kmem). Retain the
ability to run on coredumps, or on a kernel using kmem if explicitly
pointed at one.
A side effect of this change is that kvm_getswapinfo() is faster now in
the general case. If the SWIF_DUMP_TREE flag is given (pstat -ss does
this), the radix tree walker, which still uses kvm_read in any case, is
invoked, and therefore does require privilege.
Submitted by: Thomas Moestl <tmoestl@gmx.net>
Reviewed by: freebsd-audit
no longer contains kernel specific data structures, but rather
only scalar values and structures that are already part of the
kernel/user interface, specifically rusage and rtprio. It no
longer contains proc, session, pcred, ucred, procsig, vmspace,
pstats, mtx, sigiolst, klist, callout, pasleep, or mdproc. If
any of these changed in size, ps, w, fstat, gcore, systat, and
top would all stop working. The new structure has over 200 bytes
of unassigned space for future values to be added, yet is nearly
100 bytes smaller per entry than the structure that it replaced.
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.
and is module aware. Yes, this means that kvm_nlist(3) will find symbols
in loaded modules. The emulation of the nlist struct is pretty crude but
seems to work well enough for all the users in the tree that I found.
This fixes some nasty procfs problems for SMP, makes ps(1) run much faster,
and makes ps(1) even less dependent on /proc which will aid chroot and
jails alike.
To disable this facility and revert to previous behaviour:
sysctl -w kern.ps_arg_cache_limit=0
For full details see the current@FreeBSD.org mail-archives.
for over 5 years since we switched to using procfs for kvm_uread().
This cleanup was motivated by recent breakage of the default swap file
(/dev/drum) when swapon() has not been called.
track.
The $Id$ line is normally at the bottom of the main comment block in the
man page, separated from the rest of the manpage by an empty comment,
like so;
.\" $Id$
.\"
If the immediately preceding comment is a @(#) format ID marker than the
the $Id$ will line up underneath it with no intervening blank lines.
Otherwise, an additional blank line is inserted.
Approved by: bde
Include <machine/ansi.h> so that this file is self-sufficient again.
Rev.1.6 doesn't do this as claimed unless <nlist.h> has nonstandard
pollution.
Cleaned up includes.
This man page may be overdoing the cross references by referencing
man pages that are just links to other pages that are referenced.
kvm_uread() is still completely undocumented in kvm*.3.
<kvm.h> is self-sufficient again.
Moved typedefs and forward struct declarations out of __BEGIN_DECLS/
__END_DECLS.
Don't comment out the prototype for kvm_uread(). This was a 4 year
old kludge for previous breakage of self-sufficiency. The prototypwe
was broken instead.
Fixed bitrot (const poisoning) in the type of kvm_uread().
Fixed order of the declaration of kvm_uread().
fixes a type mismatch in the call to kvm_uread(). The bug has gone
undetected for almost 3 years because kvm_uproc()'s protoype has been
disabled for almost 4 years.
Trust sysctlbyname() to work properly if it succeeds.
Fixed style bugs in revs. 1.19 and 1.22.
loaded systems by retrying the sysctl() with a larger buffer if it
fails with ENOMEM. For good measure, allocate 10% more memory than
sysctl() claims is necessary.
PR: 8275
Reviewed by: David Greenman <dg@freebsd.org>
In some cases replace if (a == null) a = malloc(x); else a =
realloc(a, x); with simple reallocf(a, x). Per ANSI-C, this is
guaranteed to be the same thing.
I've been running these on my system here w/o ill effects for some
time. However, the CTM-express is at part 6 of 34 for the CAM
changes, so I've not been able to do a build world with the CAM in the
tree with these changes. Shouldn't impact anything, but...
know what they're doing if they do that. This will allow ps to use
the kvm_proc.c bits without having access to /dev/mem.
Fix kvm_proc.c to not need /dev/mem for access to argv/envp
are in kvm_uread():
- the setting of errno before checking it in the lseek() was lost.
- EOF handling was lost. kvm_uread() retried forever on EOF. EOF is
not really an error, but report it one as in rev.1.2.
- reporting of errno after a read error was lost.
Fixed style bugs in rev.1.3 and rev.1.12.
Not fixed: errno is not reported after lseek() failures.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
When malloc fails. don't try to memset NULL pointer, it cause core dump
Replace malloc+memset with calloc, theoretically it can do some
optimization of zeroing process internally
Improve error diagnostic
dead kernel debugging. The previous code was a "do nothing".
The most obvious side effect of this is that you can now do things like
this and reasonably expect them to work:
dmesg -M /var/crash/vmcore.3 -N /var/crash/kernel.3
ps -axl -M /var/crash/vmcore.3 -N /var/crash/kernel.3
A good deal of this was lifted from the gdb code to do this, as well as
from NetBSD's libkvm (which has completely different VM macros)
the statically compiled PS_STRINGS and USRSTACK variables. This prevents
programs using setproctitle from coredumping if the kernel VM is increased,
and stops libkvm users (w, ps, etc) from needing to be recompiled if only
the VM layout changes.
static executables that depend on this will need to be relinked (ie: do
this before 'ps'), but the dynamic linked stuff should be OK (ie: 'w')
Obtained from: NetBSD (not much point reinventing the wheel.. :-)
in all other places here.
This is a hack, the interface should be changed to use off_t's
everywhere around, but this will require to update all the programs
that happen to use libkvm.
Given the right circumstances, a call to kvm_open can result in a core
dump.
The diff belows fixes this (note that this change is already in the
NetBSD code). Could somebody apply this?
Gary J.
Submitted by: gj
DANGER WILL ROBINSON!
_PATH_UNIX is currently defined as the literal string "don't use this".
I am of two minds about this myself, but wanted to get something into the
tree as quickly as possible.
