Commit Graph

141 Commits

Author SHA1 Message Date
jkim
06b6c2769b Use type-specific inline function imax() instead of deprecated macro MAX().
Prodded by:	bde
2010-07-12 15:32:45 +00:00
jkim
93b88a93da Implement optional 'precision' for numbers. Previously, it was parsed but
ignored.  Some third-party modules (e.g., APCICA) prefer this format over
zero padding flag '0'.
2010-07-08 22:13:23 +00:00
ed
da18b1b80b Make /dev/klog and kern.msgbuf* MPSAFE.
Normally msgbufp is locked using Giant. Switch it to use the
msgbuf_lock. Instead of changing the tsleep() calls to msleep(), just
convert it to condvar(9).

In my opinion the locking around msgbuf_peekbytes() still remains
questionable. It looks like locks are dropped while performing copies of
multiple blocks to userspace, which may cause the msgbuf to be reset in
the mean time. At least getting it underneath from Giant should make it
a little easier for us to figure out how to solve that.

Reminded by:	rdivacky
2009-11-03 21:06:19 +00:00
ed
f02ef8e872 Remove redundant code in printf() and vprintf().
printf() and vprintf() are exactly the same, except the way arguments
are passed. Just like we see in other pieces of code (i.e. libc's
printf()), implement printf() using vprintf().

Submitted by:	Christoph Mallon <christoph mallon gmx de>
2009-02-27 13:28:54 +00:00
ed
2078a09b34 Revert previous commit to subr_prf.c and make it more tidy.
As mentioned by bz and bde, the change I made wasn't the proper way to
fix. Inspired by bde's patch, perform some small cleanups to uprintf().

Reviewed by:	bz
2009-02-27 12:50:25 +00:00
ed
280ef3dd23 Remove redundant assignment of `p'.
`p' is already initialized with `td->td_proc'. Because td is always
curthread, it is safe to initialize it without any locks.

Found by:	LLVM's scan-build
2009-02-26 12:12:34 +00:00
imp
82f181ca79 Use NULL in preference to 0 for pointers. 2009-02-03 07:51:11 +00:00
ed
c48b61a389 Revert r185891.
In r185891 I removed the newlines from messages written to /dev/console,
because it made startup messages from rc-scripts harder to read. This,
unfortunately, causes the kernel message that is printed after a
non-terminated log message to be concatenated.

This could be fixed, but on short term it's better to just revert the
change.

Reported by:	Jaakko Heinonen <jh saunalahti fi>
2008-12-21 21:54:01 +00:00
ed
4400e3e134 Remove added newlines from logged messages written to /dev/console.
The /dev/console device node logs all strings that are written to it.
When the string does not contain a trailing newline, it appends one. I
can imagine this was useful a long time ago, but with our current
rc-scripts, it generates a whole bunch of messages that look like:

| Configuring syscons:
|  blanktime
| .

By not appending the newlines, the output of `dmesg -a' is now (almost?)
exactly the same as what the user will see on the console device
(syscons, uart).
2008-12-10 21:48:05 +00:00
delphij
39ade9204d Obey signedness flag in %z case.
MFC after:	2 months
2008-11-17 23:57:40 +00:00
ed
cc3116a938 Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

  The old TTY layer has a driver model that is not abstract enough to
  make it friendly to use. A good example is the output path, where the
  device drivers directly access the output buffers. This means that an
  in-kernel PPP implementation must always convert network buffers into
  TTY buffers.

  If a PPP implementation would be built on top of the new TTY layer
  (still needs a hooks layer, though), it would allow the PPP
  implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

  With the old TTY layer, it isn't entirely safe to destroy TTY's from
  the system. This implementation has a two-step destructing design,
  where the driver first abandons the TTY. After all threads have left
  the TTY, the TTY layer calls a routine in the driver, which can be
  used to free resources (unit numbers, etc).

  The pts(4) driver also implements this feature, which means
  posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

  One of the major improvements is the per-TTY mutex, which is expected
  to improve scalability when compared to the old Giant locking.
  Another change is the unbuffered copying to userspace, which is both
  used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from:		//depot/projects/mpsafetty/...
Approved by:		philip (ex-mentor)
Discussed:		on the lists, at BSDCan, at the DevSummit
Sponsored by:		Snow B.V., the Netherlands
dcons(4) fixed by:	kan
2008-08-20 08:31:58 +00:00
julian
80d6cde009 Instead of doing comparisons using the pcpu area to see if
a thread is an idle thread, just see if it has the IDLETD
flag set. That flag will probably move to the pflags word
as it's permenent and never chenges for the life of the
system so it doesn't need locking.
2007-03-08 06:44:34 +00:00
jb
01bbbf558e Flushing the buffer is conditional on actually using the buffer. Oops. 2006-11-30 07:25:52 +00:00
jb
da35e3e55f Turn console printf buffering into a kernel option and only on
by default for sun4v where it is absolutely required.

This change moves the buffer from struct pcpu to the stack to avoid
using the critical section which created a LOR in a couple of cases
due to interaction with the tty code and kqueue. The LOR can't be
fixed with the critical section and the pcpu buffer can't be used
without the critical section.

Putting the buffer on the stack was my initial solution, but it was
pointed out that the stress on the stack might cause problems
depending on the call path. We don't have a way of creating tests
for those possible cases, so it's best to leave this as an option
for the time being. In time we may get enough data to enable this
option more generally.
2006-11-30 04:17:05 +00:00
rwatson
10d0d9cf47 Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
jb
d2bd807356 Add a cnputs() function to write a string to the console with
a lock to prevent interspersed strings written from different CPUs
at the same time.

To avoid putting a buffer on the stack or having to malloc one,
space is incorporated in the per-cpu structure. The buffer
size if 128 bytes; chosen because it's the next power of 2 size
up from 80 characters.

String writes to the console are buffered up the end of the line
or until the buffer fills. Then the buffer is flushed to all
console devices.

Existing low level console output via cnputc() is unaffected by
this change. ithread calls to log() are also unaffected to avoid
blocking those threads.

A minor change to the behaviour in a panic situation is that
console output will still be buffered, but won't be written to
a tty as before. This should prevent interspersed panic output
as a number of CPUs panic before we end up single threaded
running ddb.

Reviewed by:	scottl, jhb
MFC after:	2 weeks
2006-11-01 04:54:51 +00:00
rwatson
8b3f7ca1ce Declare security and security.bsd sysctl hierarchies in sysctl.h along
with other commonly used sysctl name spaces, rather than declaring them
all over the place.

MFC after:	1 month
Sponsored by:	nCircle Network Security, Inc.
2006-09-17 20:00:36 +00:00
jhb
a72b0bcd7f Simplify the pager support in DDB. Allowing different db commands to
install custom pager functions didn't actually happen in practice (they
all just used the simple pager and passed in a local quit pointer).  So,
just hardcode the simple pager as the only pager and make it set a global
db_pager_quit flag that db commands can check when the user hits 'q' (or a
suitable variant) at the pager prompt.  Also, now that it's easy to do so,
enable paging by default for all ddb commands.  Any command that wishes to
honor the quit flag can do so by checking db_pager_quit.  Note that the
pager can also be effectively disabled by setting $lines to 0.

Other fixes:
- 'show idt' on i386 and pc98 now actually checks the quit flag and
  terminates early.
- 'show intr' now actually checks the quit flag and terminates early.
2006-07-12 21:22:44 +00:00
jkim
7e4fc3b8f9 Implement printf 'X' conversion for both libstand and kernel. 2006-03-09 22:37:34 +00:00
scottl
2144501c63 Always print a newline char at the end of the line. 2006-02-25 16:20:22 +00:00
rwatson
0106e151c3 Acquire Giant in uprintf() and tprintf() rather than asserting it. In
the vast majority of cases, these functions are called without mutexes
held, meaning that in all but two cases, there will be no ordering
issues with doing this, and it will eliminate the need for changes in
the caller.  In two cases, mutexes are held, so Giant must be acquired
before those mutexes such that uprintf() and tprintf() recurse Giant
rather than generating a lock order reversal.

Suggested by:	bde
2005-09-26 08:02:24 +00:00
rwatson
8448d393fa Correct an incorrect comment from the dawn of time: neither tprintf()
nor uprintf() is believed to perform tsleep() or msleep() as written,
as ttycheckoutq() is called with '0' as its sleep argument.

Remove recently added WITNESS warnings for sleep as the comment was
incorrect.  This should silence a warning from the nfs_timer() code.

Discussed with:	bde
2005-09-20 09:55:36 +00:00
rwatson
c479a90eb8 Add GIANT_REQUIRED and WITNESS sleep warnings to uprintf() and tprintf(),
as they both interact with the tty code (!MPSAFE) and may sleep if the
tty buffer is full (per comment).

Modify all consumers of uprintf() and tprintf() to hold Giant around
calls into these functions.  In most cases, this means adding an
acquisition of Giant immediately around the function.  In some cases
(nfs_timer()), it means acquiring Giant higher up in the callout.

With these changes, UFS no longer panics on SMP when either blocks are
exhausted or inodes are exhausted under load due to races in the tty
code when running without Giant.

NB: Some reduction in calls to uprintf() in the svr4 code is probably
desirable.

NB: In the case of nfs_timer(), calling uprintf() while holding a mutex,
or even in a callout at all, is a bad idea, and will generate warnings
and potential upset.  This needs to be fixed, but was a problem before
this change.

NB: uprintf()/tprintf() sleeping is generally a bad ideas, as is having
non-MPSAFE tty code.

MFC after:	1 week
2005-09-19 16:51:43 +00:00
delphij
5f683ee68d When padding with zero, do pad after prefixes rather than padding
before prefixes.

Use cases:
	printf("%05d", -42);   -->   "00-42"   (should be "-0042")
	printf("%#05x", 12);   -->   "000xc"   (should be "0x00c")

Submitted by:	Oliver Fromme
PR:		kern/85520
MFC After:	1 week
2005-09-04 18:03:45 +00:00
phk
40bead9126 If we ignore an unknown % sequence, we must stop interpreting the
remaining % arguments because the varargs are now out of sync and
there is a risk that we might for instance dereference an integer
in a %s argument.

Sponsored by: Napatech.com
2005-09-03 10:28:08 +00:00
dwhite
1d894721d3 Make "show msgbuf" use the pager instead of blasting the whole thing out.
MFC after:	3 days
2005-06-06 22:18:32 +00:00
phk
46c303a78b Constify hexdump() harder. 2005-04-06 10:14:13 +00:00
phk
d6c8765efc In stange circumstances we may end up being the last reference to a
session in tprintf().   SESSRELE() needs to properly dispose of the
sessions mutex.

Add sessrele() which does the proper cleanup and have SESSRELE() call it.

Use SESSRELE also in pgdelete().

Found by:	Coverity (ID:526)
2005-03-17 08:44:41 +00:00
marcel
54e2d39fa0 Update for the KDB framework:
o  Check kdb_active instead of db_active and do so unconditionally.
2004-07-10 21:43:23 +00:00
phk
b9f13e4266 Clean up and wash struct iovec and struct uio handling.
Add copyiniov() which copies a struct iovec array in from userland into
a malloc'ed struct iovec.  Caller frees.

Change uiofromiov() to malloc the uio (caller frees) and name it
copyinuio() which is more appropriate.

Add cloneuio() which returns a malloc'ed copy.  Caller frees.

Use them throughout.
2004-07-10 15:42:16 +00:00
green
e57eac4be2 Add a sysctl/tunable, "kern.always_console_output", that lets you set
output to permanently (not ephemerally) go to the console.  It is also
sent to any other console specified by TIOCCONS as normal.

While I'm here, document the kern.log_console_output sysctl.
2004-06-18 20:12:42 +00:00
imp
74cf37bd00 Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core
2004-04-05 21:03:37 +00:00
njl
a3ce894968 Add support for 'h' and 'hh' modifiers for printf(9).
Submitted by:	Bruno Ducrot <ducrot AT poupinou.org>
Reviewed by:	bde
2004-02-19 05:29:39 +00:00
scottl
2b68e67c6d Re-arrange and consolidate some random debugging stuff 2003-12-07 05:04:49 +00:00
phk
eb30c92e49 Revert stuff which accidentally ended up in the previous commit. 2003-07-22 10:36:36 +00:00
phk
c4a9334fa6 Don't attempt to inline large functions mb_alloc() and mb_free(),
it more than doubles the text size of this file.

GCC has wisely ignored us on this previously
2003-07-22 10:24:41 +00:00
iedowse
768b08c167 When DDB is active, always send printf() output directly to the
console, even if there is a TIOCCONS console tty. We were already
doing this after a panic, but it's also useful when entering DDB
for some other reason too.
2003-06-22 03:20:24 +00:00
iedowse
65000a220a Use a new message buffer `consmsgbuf' to forward messages to a
TIOCCONS console (e.g. xconsole) via a timeout routine instead of
calling into the tty code directly from printf(). This fixes a
number of cases where calling printf() at the wrong time (such as
with locks held) would cause a panic if xconsole is running.

The TIOCCONS message buffer is 8k in size by default, but this can
be changed with the kern.consmsgbuf_size sysctl. By default, messages
are checked for 5 times per second. The timer runs and the buffer
memory remains allocated only at times when a TIOCCONS console is
active.

Discussed on:	freebsd-arch
2003-06-22 02:54:33 +00:00
iedowse
6bb0e5cb46 Replace the code for reading and writing the kernel message buffer
with a new implementation that has a mostly reentrant "addchar"
routine, supports multiple message buffers in the kernel, and hides
the implementation details from callers.

The new code uses a kind of sequence number to represend the current
read and write positions in the buffer. This approach (suggested
mainly by bde) permits the read and write pointers to be maintained
separately, which reduces the number of atomic operations that are
required. The "mostly reentrant" above refers to the way that while
it is now always safe to have any number of concurrent writers,
readers could see the message buffer after a writer has advanced
the pointers but before it has witten the new character.

Discussed on:	freebsd-arch
2003-06-22 02:18:31 +00:00
obrien
3b8fff9e4c Use __FBSDID(). 2003-06-11 00:56:59 +00:00
phk
145891d899 Remove unused variable(s).
Remove break after goto

Found by:       FlexeLint
2003-05-31 20:11:33 +00:00
jhb
872336ea36 Don't assume that p_session hasn't changed out from under us after unlocking
the process and session.  Instead, cache a true reference to the session
when we do the hold and release our reference on that session.  This avoids
the need for the proc lock when dropping the reference.
2003-04-17 22:30:43 +00:00
iedowse
b399d5ecbd Add a checksum to the kernel message buffer, and update it every
time a character is written. Use this at boot time to reject the
existing buffer contents if they are corrupt. This fixes a problem
seen on some hardware (especially laptops) where the message buffer
gets partially corrupted during a short power cycle or reset, but
the msgbuf structure is left intact so it gets reused, resulting
in random junk and control characters appearing in dmesg and
/var/log/messages.

PR:		kern/28497
2003-03-28 02:50:10 +00:00
phk
e059b79437 Including <sys/stdint.h> is (almost?) universally only to be able to use
%j in printfs, so put a newsted include in <sys/systm.h> where the printf
prototype lives and save everybody else the trouble.
2003-03-18 08:45:25 +00:00
imp
cf874b345d Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
phk
1abb95308b Add vsnrprintf() which is just like vsnprintf() but takes a "radix"
argument for the kernel-special %r format.
2003-02-04 10:00:34 +00:00
alfred
bf8e8a6e8f Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
jhb
09a741fae6 Cast the integer read as the first argument for %b to an unsigned integer
so it's value is not sign extended when assigned to the uintmax_t variable
used internally by printf.  For example, if bit 31 is set in the cpuid
feature word, then %b would print out the initial value as a 16 character
hexadecimal value.  Now it only prints out an 8 character value.

Reviewed by:	bde
2003-01-07 18:17:18 +00:00
phk
bc8317a9cc Move #include of ddb/ddb.h up with the rest. 2003-01-04 20:15:32 +00:00
tmm
6bce41dbe0 Make the msg_size, msg_bufx and msg_bufr memebers of struct msgbuf
signed, since they describe a ring buffer and signed arithmetic is
performed on them. This avoids some evilish casts.

Since this changes all but two members of this structure, style(9)
those remaining ones, too.

Requested by:	bde
Reviewed by:	bde (earlier version)
2002-11-14 16:11:12 +00:00