Commit Graph

85 Commits

Author SHA1 Message Date
Warner Losh
fbbd9655e5 Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00
Bruce Evans
2b7a7ace9e In ddb ps, left justify the non-numeric fields 'state' and 'wmesg' and
the fixed-width numeric field 'wchan', as in ps(1).  They were sort
of centered, although the template shows 'state' as right-justified.
The `wmesg' field very rarely has a prefix of '*' (for lock names)
that is still to the left of the header, and the width of this field
is reduced from 8 to 7 (more than 6 is an error).

The 'wmesg' and 'wchan' fields are still misnamed and poorly handled.
They are named sort of backwards relative to ps(1):
- wmesg in ddb = mwchan in ps
- wmesg in ddb = wchan in ps (if it is a wait channel name, not a lock name)
- wchan in ddb = nwchan in ps
ddb ps wastes lots of space for the unimportant 'wchan' field (20
columns altogether on 64-bit arches).  ps(1) documents using a
compressed format, but the compression only omits leading nybbles of
0 so it has neveqr worked on arches that put the kernel in the top half
of the address space.  It just avoids wasting space for an 0x prefix.
2016-08-14 15:26:40 +00:00
Conrad Meyer
5f00f45775 Fix ddb "show proc" to show full arguments
PR:		200052
Submitted by:	Chang-Hsien Tsai <luke.tw AT gmail.com>
2016-08-01 22:41:50 +00:00
Konstantin Belousov
2d19b736ed Rewrite subr_sleepqueue.c use of callouts to not depend on the
specifics of callout KPI.  Esp., do not depend on the exact interface
of callout_stop(9) return values.

The main change is that instead of requiring precise callouts, code
maintains absolute time to wake up.  Callouts now should ensure that a
wake occurs at the requested moment, but we can tolerate both run-away
callout, and callout_stop(9) lying about running callout either way.

As consequence, it removes the constant source of the bugs where
sleepq_check_timeout() causes uninterruptible thread state where the
thread is detached from CPU, see e.g. r234952 and r296320.

Patch also removes dual meaning of the TDF_TIMEOUT flag, making code
(IMO much) simpler to reason about.

Tested by:	pho
Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
Differential revision:	https://reviews.freebsd.org/D7137
2016-07-28 09:09:55 +00:00
Konstantin Belousov
16952e289f Avoid NULL pointer dereference, for a process which is not (yet) a
member of a process group, e.g. during the system bootstrap.

Submitted by:	Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
MFC after:	1 week
2016-04-15 09:13:01 +00:00
Conrad Meyer
c975a5d359 Add td_swinvoltick to track last involuntary context switch
Expose in DDB via "show thread."

Reviewed by:	markj
Sponsored by:	EMC / Isilon Storage Division
2016-03-25 19:35:29 +00:00
Konstantin Belousov
edc8222303 Make kstack_pages a tunable on arm, x86, and powepc. On i386, the
initial thread stack is not adjusted by the tunable, the stack is
allocated too early to get access to the kernel environment. See
TD0_KSTACK_PAGES for the thread0 stack sizing on i386.

The tunable was tested on x86 only.  From the visual inspection, it
seems that it might work on arm and powerpc.  The arm
USPACE_SVC_STACK_TOP and powerpc USPACE macros seems to be already
incorrect for the threads with non-default kstack size.  I only
changed the macros to use variable instead of constant, since I cannot
test.

On arm64, mips and sparc64, some static data structures are sized by
KSTACK_PAGES, so the tunable is disabled.

Sponsored by:	The FreeBSD Foundation
MFC after:	2 week
2015-08-10 17:18:21 +00:00
Zbigniew Bodek
721555e7ee Fix KSTACK_PAGES issue when the default value was changed in KERNCONF
If KSTACK_PAGES was changed to anything alse than the default,
the value from param.h was taken instead in some places and
the value from KENRCONF in some others. This resulted in
inconsistency which caused corruption in SMP envorinment.

Ensure all places where KSTACK_PAGES are used the opt_kstack_pages.h
is included.

The file opt_kstack_pages.h could not be included in param.h
because was breaking the toolchain compilation.

Reviewed by:   kib
Obtained from: Semihalf
Sponsored by:  The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3094
2015-07-16 10:46:52 +00:00
Pedro F. Giffuni
cd508278c1 ddb: finish converting boolean values.
The replacement started at r283088 was necessarily incomplete without
replacing boolean_t with bool.  This also involved cleaning some type
mismatches and ansifying old C function declarations.

Pointed out by:	bde
Discussed with:	bde, ian, jhb
2015-05-21 15:16:18 +00:00
Pedro F. Giffuni
2b490bc747 ddb: stop boolean screaming.
TRUE --> true
FALSE--> false

Hinted by:	NetBSD
2015-05-18 22:27:46 +00:00
Pedro F. Giffuni
1549fb22e6 ddb: space/tab fixes.
No functional change.

MFC after:	3 days
2014-10-11 20:25:19 +00:00
Sergey Kandaurov
148ddfed15 Use FOREACH_PROC_IN_SYSTEM instead of using its unrolled form.
Reviewed by:	kib
2011-12-18 15:36:21 +00:00
Konstantin Belousov
9ab83ecbcb Add 'findstack' ddb command to search either the thread kernel stack
or cached stack containing the specified kernel virtual address.

Discussed with:	pho
MFC after:	1 week
2011-12-16 11:44:20 +00:00
John Baldwin
41b1c25960 Trim some additional unnecessary <linker_set.h> includes.
MFC after:	1 week
2011-04-28 17:59:33 +00:00
Edward Tomasz Napierala
3745cc73d0 Replace several instances of 'if (!a & b)' with 'if (!(a &b))' in order
to silence newer GCC versions.
2010-01-08 15:44:49 +00:00
John Baldwin
3538cf0cbe Put square backets ([]) around process names for system processes to patch
the behavior of ps(1).
2009-10-01 19:12:14 +00:00
Attilio Rao
f15b761da5 Print out the container lock when showing the thread state in DDB.
Tested by:	benjsc
2008-06-18 20:42:01 +00:00
Sam Leffler
9e340a6190 enable dynamic addition of "show all" commands
MFC after:	3 weeks
2008-03-25 20:36:32 +00:00
Marcel Moolenaar
a0f4a3a63b Print the stack bounds of the thread. 2007-10-16 17:52:59 +00:00
Jeff Roberson
b61ce5b0e6 - Move all of the PS_ flags into either p_flag or td_flags.
- p_sflag was mostly protected by PROC_LOCK rather than the PROC_SLOCK or
   previously the sched_lock.  These bugs have existed for some time.
 - Allow swapout to try each thread in a process individually and then
   swapin the whole process if any of these fail.  This allows us to move
   most scheduler related swap flags into td_flags.
 - Keep ki_sflag for backwards compat but change all in source tools to
   use the new and more correct location of P_INMEM.

Reported by:	pho
Reviewed by:	attilio, kib
Approved by:	re (kensmith)
2007-09-17 05:31:39 +00:00
Julian Elischer
ad1e7d285a Threading cleanup.. part 2 of several.
Make part of John Birrell's KSE patch permanent..
Specifically, remove:
Any reference of the ksegrp structure. This feature was
never fully utilised and made things overly complicated.
All code in the scheduler that tried to make threaded programs
fair to unthreaded programs.  Libpthread processes will already
do this to some extent and libthr processes already disable it.

Also:
Since this makes such a big change to the scheduler(s), take the opportunity
to rename some structures and elements that had to be moved anyhow.
This makes the code a lot more readable.

The ULE scheduler compiles again but I have no idea if it works.

The 4bsd scheduler still reqires a little cleaning and some functions that now do
ALMOST nothing will go away, but I thought I'd do that as a separate commit.

Tested by David Xu, and Dan Eischen using libthr and libpthread.
2006-12-06 06:34:57 +00:00
John Birrell
8460a577a4 Make KSE a kernel option, turned on by default in all GENERIC
kernel configs except sun4v (which doesn't process signals properly
with KSE).

Reviewed by:	davidxu@
2006-10-26 21:42:22 +00:00
John Baldwin
d25168e14e Fix two nits in the ps header that offset each other making them largely
unnoticable.
2006-08-01 22:30:55 +00:00
John Baldwin
8b6d68671b Some cosmetic tweaks:
- Right justify 'pid' label.
- Move the uid column to the right 2 columns so that the 3 process id
  columns (pid, ppid, pgrp) are grouped together.
- Expand the uid column to 5 chars.
- Don't indent the tid for multithreaded processes.

Requested by:	bde (1, 2, 4)
2006-08-01 15:29:46 +00:00
John Baldwin
19e9205a23 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
John Baldwin
10fd453475 Use __LP64__ rather than the PTR64 hack.
Suggested by:	ru
2006-05-11 21:59:55 +00:00
John Baldwin
a421d57149 Sort includes. 2006-04-27 22:09:18 +00:00
John Baldwin
eefcd2a1e6 A whitespace fix.
Submitted by:	bde
2006-04-27 22:02:27 +00:00
John Baldwin
60b0d00999 Drop locking comments. ddb functions should never use locking anyway and
no other ddb functions try to annotate what locking would otherwise be
appropriate in comments.

Prodded by:	bde
2006-04-27 21:59:43 +00:00
John Baldwin
c9a08d1cad - Overhaul the 'ps' command in ddb to be mostly readable again. :) It is
now back to using fixed-size columns for output and each line of output
  should fit in 80 columns on both 32-bit and 64-bit architectures.  In
  general the output is close to that of the userland ps(1) with the
  exception that the 'wmesg' field is mostly similar to the "state" field
  in top(1) in that it will show either a wmesg, a lock name (prefixed with
  an *), "CPU xx" (for a running thread), or nothing if none of those three
  conditions are true.  It also respects td_name when listing threads in
  a multithreaded process.  There is a somewhat evilly-defined PTR64 macro
  I use to make account for the change in the size of the 'wchan' column
  in the formatted output (wchan is now the only pointer in the ps output
  and is available so it can be passed to 'show sleepq', 'show turnstile',
  or 'show lock').
- Add two new commands "show proc [process]" and "show thread [thread]"
  that show details about the specified process or thread (specified
  either by pid/tid or pointer), respectively.  If an address it not
  specified, it uses the current kdb thread.
2006-04-25 20:34:04 +00:00
David Schultz
626ff2081f Remove the uarea column from the DDB 'ps' display, and from grog's gdb
scripts.

Reviewed by:	arch@
2004-11-20 02:32:42 +00:00
John Baldwin
d39d4a6e64 - Change the ddb paging "support" to use a variable (db_lines_per_page) to
control the number of lines per page rather than a constant.  The variable
  can be examined and changed in ddb as '$lines'.  Setting the variable to
  0 will effectively turn off paging.
- Change db_putchar() to force out pending whitespace before outputting
  newlines and carriage returns so that one can rub out content on the
  current line via '\r     \r' type strings.
- Change the simple pager to rub out the --More-- prompt explicitly when
  the routine exits.
- Add some aliases to the simple pager to make it more compatible with
  more(1): 'e' and 'j' do a single line.  'd' does half a page, and
  'f' does a full page.

MFC after:	1 month
Inspired by:	kris
2004-11-01 22:15:15 +00:00
Julian Elischer
ed062c8d66 Refactor a bunch of scheduler code to give basically the same behaviour
but with slightly cleaned up interfaces.

The KSE structure has become the same as the "per thread scheduler
private data" structure. In order to not make the diffs too great
one is #defined as the other at this time.

The KSE (or td_sched) structure is  now allocated per thread and has no
allocation code of its own.

Concurrency for a KSEGRP is now kept track of via a simple pair of counters
rather than using KSE structures as tokens.

Since the KSE structure is different in each scheduler, kern_switch.c
is now included at the end of each scheduler. Nothing outside the
scheduler knows the contents of the KSE (aka td_sched) structure.

The fields in the ksegrp structure that are to do with the scheduler's
queueing mechanisms are now moved to the kg_sched structure.
(per ksegrp scheduler private data structure). In other words how the
scheduler queues and keeps track of threads is no-one's business except
the scheduler's. This should allow people to write experimental
schedulers with completely different internal structuring.

A scheduler call sched_set_concurrency(kg, N) has been added that
notifies teh scheduler that no more than N threads from that ksegrp
should be allowed to be on concurrently scheduled. This is also
used to enforce 'fainess' at this time so that a ksegrp with
10000 threads can not swamp a the run queue and force out a process
with 1 thread, since the current code will not set the concurrency above
NCPU, and both schedulers will not allow more than that many
onto the system run queue at a time. Each scheduler should eventualy develop
their own methods to do this now that they are effectively separated.

Rejig libthr's kernel interface to follow the same code paths as
linkse for scope system threads. This has slightly hurt libthr's performance
but I will work to recover as much of it as I can.

Thread exit code has been cleaned up greatly.
exit and exec code now transitions a process back to
'standard non-threaded mode' before taking the next step.
Reviewed by:	scottl, peter
MFC after:	1 week
2004-09-05 02:09:54 +00:00
Marcel Moolenaar
37224cd3fc Mega update for the KDB framework: turn DDB into a KDB backend.
Most of the changes are a direct result of adding thread awareness.
Typically, DDB_REGS is gone. All registers are taken from the
trapframe and backtraces use the PCB based contexts. DDB_REGS was
defined to be a trapframe on all platforms anyway.
Thread awareness introduces the following new commands:
	thread X	switch to thread X (where X is the TID),
	show threads	list all threads.

The backtrace code has been made more flexible so that one can
create backtraces for any thread by giving the thread ID as an
argument to trace.

With this change, ia64 has support for breakpoints.
2004-07-10 23:47:20 +00:00
Warner Losh
f36cfd49ad Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson
2004-04-07 20:46:16 +00:00
John Baldwin
44f3b09204 Switch the sleep/wakeup and condition variable implementations to use the
sleep queue interface:
- Sleep queues attempt to merge some of the benefits of both sleep queues
  and condition variables.  Having sleep qeueus in a hash table avoids
  having to allocate a queue head for each wait channel.  Thus, struct cv
  has shrunk down to just a single char * pointer now.  However, the
  hash table does not hold threads directly, but queue heads.  This means
  that once you have located a queue in the hash bucket, you no longer have
  to walk the rest of the hash chain looking for threads.  Instead, you have
  a list of all the threads sleeping on that wait channel.
- Outside of the sleepq code and the sleep/cv code the kernel no longer
  differentiates between cv's and sleep/wakeup.  For example, calls to
  abortsleep() and cv_abort() are replaced with a call to sleepq_abort().
  Thus, the TDF_CVWAITQ flag is removed.  Also, calls to unsleep() and
  cv_waitq_remove() have been replaced with calls to sleepq_remove().
- The sched_sleep() function no longer accepts a priority argument as
  sleep's no longer inherently bump the priority.  Instead, this is soley
  a propery of msleep() which explicitly calls sched_prio() before
  blocking.
- The TDF_ONSLEEPQ flag has been dropped as it was never used.  The
  associated TDF_SET_ONSLEEPQ and TDF_CLR_ON_SLEEPQ macros have also been
  dropped and replaced with a single explicit clearing of td_wchan.
  TD_SET_ONSLEEPQ() would really have only made sense if it had taken
  the wait channel and message as arguments anyway.  Now that that only
  happens in one place, a macro would be overkill.
2004-02-27 18:52:44 +00:00
Poul-Henning Kamp
71b797c176 Label the uarea address as such in DDB's ps output 2003-08-30 19:06:57 +00:00
John Baldwin
3f2a1b0656 Update the 'ps', 'show pci', and 'show ktr' ddb commands to use the new
pager callout instead of homerolling their own paging facility.
2003-07-31 17:29:42 +00:00
John Baldwin
cb075651f8 Whitespace nit. 2003-07-30 20:59:36 +00:00
David Xu
0e2a4d3aeb Rename P_THREADED to P_SA. P_SA means a process is using scheduler
activations.
2003-06-15 00:31:24 +00:00
David E. O'Brien
753960f7c4 Use __FBSDID(). 2003-06-10 22:09:23 +00:00
Julian Elischer
b410626185 Attempt to crunch down the thread state info so that it is more likely to
fit on one line. Account for threads better.

* No need to report that it is on a sleep queue if it is actually sleeping
* "Normal" state is almost ubiquitous.. only report abnormal states.
* increment the #lines count for each separate thread shown in threaded
  programs.

makes it less likely that a threaded program will make all the data
on a screen overflow off the top of the screen.
2003-06-06 20:28:11 +00:00
John Baldwin
a85b6f827b Handle the TDS_INACTIVE state by printing '[INACTIVE]' instead of
panic'ing.  Also, for unknown thread states, print out the value rather
than panic.  Panic'ing in the debugger is pointless at best.
2003-06-06 17:20:47 +00:00
John Baldwin
ac39898e7e Whitespace nits. 2003-06-06 17:19:27 +00:00
Julian Elischer
060563ec50 Move the _oncpu entry from the KSE to the thread.
The entry in the KSE still exists but it's purpose will change a bit
when we add the ability to lock a KSE to a cpu.
2003-04-10 17:35:44 +00:00
Julian Elischer
ac2e415327 Change the process flags P_KSES to be P_THREADED.
This is just a cosmetic change but I've been meaning to do it for about a year.
2003-02-27 02:05:19 +00:00
Jeff Roberson
5215b1872f - Split the struct kse into struct upcall and struct kse. struct kse will
soon be visible only to schedulers.  This greatly simplifies much the
   KSE code.

Submitted by:	davidxu
2003-02-17 05:14:26 +00:00
Julian Elischer
6f8132a867 Reversion of commit by Davidxu plus fixes since applied.
I'm not convinced there is anything major wrong with the patch but
them's the rules..

I am using my "David's mentor" hat to revert this as he's
offline for a while.
2003-02-01 12:17:09 +00:00
David Xu
0dbb100b9b Move UPCALL related data structure out of kse, introduce a new
data structure called kse_upcall to manage UPCALL. All KSE binding
and loaning code are gone.

A thread owns an upcall can collect all completed syscall contexts in
its ksegrp, turn itself into UPCALL mode, and takes those contexts back
to userland. Any thread without upcall structure has to export their
contexts and exit at user boundary.

Any thread running in user mode owns an upcall structure, when it enters
kernel, if the kse mailbox's current thread pointer is not NULL, then
when the thread is blocked in kernel, a new UPCALL thread is created and
the upcall structure is transfered to the new UPCALL thread. if the kse
mailbox's current thread pointer is NULL, then when a thread is blocked
in kernel, no UPCALL thread will be created.

Each upcall always has an owner thread. Userland can remove an upcall by
calling kse_exit, when all upcalls in ksegrp are removed, the group is
atomatically shutdown. An upcall owner thread also exits when process is
in exiting state. when an owner thread exits, the upcall it owns is also
removed.

KSE is a pure scheduler entity. it represents a virtual cpu. when a thread
is running, it always has a KSE associated with it. scheduler is free to
assign a KSE to thread according thread priority, if thread priority is changed,
KSE can be moved from one thread to another.

When a ksegrp is created, there is always N KSEs created in the group. the
N is the number of physical cpu in the current system. This makes it is
possible that even an userland UTS is single CPU safe, threads in kernel still
can execute on different cpu in parallel. Userland calls kse_create to add more
upcall structures into ksegrp to increase concurrent in userland itself, kernel
is not restricted by number of upcalls userland provides.

The code hasn't been tested under SMP by author due to lack of hardware.

Reviewed by: julian
2003-01-26 11:41:35 +00:00
Julian Elischer
93a7aa79d6 Add code to ddb to allow backtracing an arbitrary thread.
(show thread {address})

Remove the IDLE kse state and replace it with a change in
the way threads sahre KSEs. Every KSE now has a thread, which is
considered its "owner" however a KSE may also be lent to other
threads in the same group to allow completion of in-kernel work.
n this case the owner remains the same and the KSE will revert to the
owner when the other work has been completed.

All creations of upcalls etc. is now done from
kse_reassign() which in turn is called from mi_switch or
thread_exit(). This means that special code can be removed from
msleep() and cv_wait().

kse_release() does not leave a KSE with no thread any more but
converts the existing thread into teh KSE's owner, and sets it up
for doing an upcall. It is just inhibitted from being scheduled until
there is some reason to do an upcall.

Remove all trace of the kse_idle queue since it is no-longer needed.
"Idle" KSEs are now on the loanable queue.
2002-12-28 01:23:07 +00:00