Before safecopies, the IO_ENDPT and DL_ENDPT message fields were needed
to know which actual process to copy data from/to, as that process may
not always be the caller. Now that we have full safecopy support, these
fields have become useless for that purpose: the owner of the grant is
*always* the caller. Allowing the caller to supply another endpoint is
in fact dangerous, because the callee may then end up using a grant
from a third party. One could call this a variant of the confused
deputy problem.
From now on, safecopy calls should always use the caller's endpoint as
grant owner. This fully obsoletes the DL_ENDPT field in the
inet/ethernet protocol. IO_ENDPT has other uses besides identifying the
grant owner though. This patch renames IO_ENDPT to USER_ENDPT, not only
because that is a more fitting name (it should never be used for I/O
after all), but also in order to intentionally break any old system
source code outside the base system. If this patch breaks your code,
fixing it is fairly simple:
- DL_ENDPT should be replaced with m_source;
- IO_ENDPT should be replaced with m_source when used for safecopies;
- IO_ENDPT should be replaced with USER_ENDPT for any other use, e.g.
when setting REP_ENDPT, matching requests in CANCEL calls, getting
DEV_SELECT flags, and retrieving of the real user process's endpoint
in DEV_OPEN.
The changes in this patch are binary backward compatible.
asynchronous message resulted in an error.
The model here is that:
- Iff a sender wishes to be notified, the sender MUST check for errors
BEFORE sending another asynchronous message.
The reason is that in order to remember the error code, we can't clean up
the message table and hence we risk running out of table space. This is
less of a problem when the sender enables notifications only for errors.
This library includes various random and minix-specific functions
included in the Minix libc. Most of them should be part of libsys,
and in general it would be nice to extinguish this library over
time.
- Remove sanity checks for initialized mutexes and condition variables. This
significantly boosts performance. The checks can be turned back on by
compiling libmthread with MTHREAD_STRICT. According to POSIX operations on
uninitialized variables are a MAY fail if, therefore allowing this
optimization.
- Test59 has to be accommodated to the lack of sanity checks on uninitialized
variables in the library. It specifically tests for them and will run into
segfaults when the checks are absent in the library.
- Fix a few bugs related to the scheduler
- Do some general code cleanups
This patch fixes some wrong error code number in nbsd libc's sys/errno.h
and adds new ones.
As in NetBSD the errno.h is used to automatically generate errlist.c array,
EBADCPU set to 1000 to be a bit too large, so we instruct the awk script
to stop at EDEADEPT (ELAST).
This patch changes the NBSD libc stat implemenation and adds
fstat (and headers), taken from current libc.
It also adds weaks alias to functions in the resolver that
were removed from public use in NetBSD but that are still
used by Minix, and fixes a NetBSD non-REENTRANT bug in
in gen/initdir.c.
This patch add a few weak_alias forgotten, so that non-internal
symbols are defined to be used from application.
Modifying only the minix-specific part, this patch needs no update
to minix-port.patch.
This patch mainly copies and modifies files existing in
the current libc implementing minix specific functions.
To keep consisten with the NetBSD libc, we remove
namespace stubs and we use "namespace.h" and weak
links.
This patch contains changes to NetBSD libc code base to make it
compile and work on Minix. Some of them are due to actual NetBSD
libc bugs, as we're compiling it in non-reentrant mode and with
a.out support, something not exactly frequent in NetBSD.
Others are proper fixes to port it to Minix (mostly sa_len
parameter missing in socket and a few mmap from files).
This patch imports the unmodified current version of NetBSD libc.
The NetBSD includes are in /nbsd_include, while the libc code itself is
split between lib/nbsd_libc and common/lib/libc.
M include/Makefile
A include/minix/input.h
M include/minix/com.h
M drivers/tty/keyboard.c
M drivers/tty/tty.c
M drivers/tty/tty.h
M include/minix/syslib.h
M lib/libsys/Makefile
A lib/libsys/input.c
this is a fix for e.g. the situation where lots of processes die
instantly, and PM has to send an asyn msg for each one to VFS, and
panics if there are too many. there are likely more situations in
which this table should be dependent on the no. of processes.
reported by pikpik on #minix3.
Before, the 'main thread' of a process was never taken into account anywhere in
the library, causing mutexes not to work properly (and consequently, neither
did the condition variables). For example, if the 'main thread' (that is, the
thread which is started at the beginning of a process; not a spawned thread by
the library) would lock a mutex, it wasn't actually locked.
- profile --nmi | --rtc sets the profiling mode
- --rtc is default, uses BIOS RTC, cannot profile kernel the presetted
frequency values apply
- --nmi is only available in APIC mode as it uses the NMI watchdog, -f
allows any frequency in Hz
- both modes use compatible data structures
- sys_schedule can change only selected values, -1 means that the
current value should be kept unchanged. For instance we mostly want
to change the scheduling quantum and priority but we want to keep
the process at the current cpu
- RS can hand off its processes to scheduler
- service can read the destination cpu from system.conf
- RS can pass the information farther
- Remove unused includes.
- Add include guards to headers.
- Use unsigned variables in case they're never going to hold a negative
value. This causes GCC's complaints to disappear and should make flexelint
a lot happier, too.
- Make functions private when they're used only within a module.
- Remove unused variables.
- Add casts where appropriate.
-Makefile updates
-Update mkdep
-Build fixes/warning cleanups for some programs
-Restore leading underscores on global syms in kernel asm files
-Increase ramdisk size
In this second phase, scheduling is moved from PM to its own
scheduler (see r6557 for phase one). In the next phase we hope to a)
include useful information in the "out of quantum" message and b)
create some simple scheduling policy that makes use of that
information.
When the system starts up, PM will iterate over its process table and
ask SCHED to take over scheduling unprivileged processes. This is
done by sending a SCHEDULING_START message to SCHED. This message
includes the processes endpoint, the parent's endpoint and its nice
level. The scheduler adds this process to its schedproc table, issues
a schedctl, and returns its own endpoint to PM - as the endpoint of
the effective scheduler. When a process terminates, a SCHEDULING_STOP
message is sent to the scheduler.
The reason for this effective endpoint is for future compatibility.
Some day, we may have a scheduler that, instead of scheduling the
process itself, forwards the SCHEDULING_START message on to another
scheduler.
PM has information on who schedules whom. As such, scheduling
messages from user-land are sent through PM. An example is when
processes change their priority, using nice(). In that case, a
getsetpriority message is sent to PM, which then sends a
SCHEDULING_SET_NICE to the process's effective scheduler.
When a process is forked through PM, it inherits its parent's
scheduler, but is spawned with an empty quantum. As before, a request
to fork a process flows through VM before returning to PM, which then
wakes up the child process. This flow has been modified slightly so
that PM notifies the scheduler of the new process, before waking up
the child process. If the scheduler fails to take over scheduling,
the child process is torn down and the fork fails with an erroneous
value.
Process priority is entirely decided upon using nice levels. PM
stores a copy of each process's nice level and when a child is
forked, its parent's nice level is sent in the SCHEDULING_START
message. How this level is mapped to a priority queue is up to the
scheduler. It should be noted that the nice level is used to
determine the max_priority and the parent could have been in a lower
priority when it was spawned. To prevent a CPU intensive process from
hawking the CPU by continuously forking children that get scheduled
in the max_priority, the scheduler should determine in which queue
the parent is currently scheduled, and schedule the child in that
same queue.
Other fixes: The USER_Q in kernel/proc.h was incorrectly defined as
NR_SCHED_QUEUES/2. That results in a "off by one" error when
converting priority->nice->priority for nice=0. This also had the
side effect that if someone were to set the MAX_USER_Q to something
else than 0, then USER_Q would be off.
model to an instance-based model. Each ethernet driver instance is now
responsible for exactly one network interface card. The port field in
/etc/inet.conf now acts as an instance field instead.
This patch also updates the data link protocol. This update:
- eliminates the concept of ports entirely;
- eliminates DL_GETNAME entirely;
- standardizes on using m_source for IPC and DL_ENDPT for safecopies;
- removes error codes from TASK/STAT replies, as they were unused;
- removes a number of other old or unused fields;
- names and renames a few other fields.
All ethernet drivers have been changed to:
- conform to the new protocol, and exactly that;
- take on an instance number based on a given "instance" argument;
- skip that number of PCI devices in probe iterations;
- use config tables and environment variables based on that number;
- no longer be limited to a predefined maximum of cards in any way;
- get rid of any leftover non-safecopy support and other ancient junk;
- have a correct banner protocol figure, or none at all.
Other changes:
* Inet.conf is now taken to be line-based, and supports #-comments.
No existing installations are expected to be affected by this.
* A new, select-based asynchio library replaces the old one.
Kindly contributed by Kees J. Bot.
* Inet now supports use of select() on IP devices.
Combined, the last two changes together speed up dhcpd
considerably in the presence of multiple interfaces.
* A small bug has been fixed in nonamed.
