Commit graph

27 commits

Author SHA1 Message Date
Cristiano Giuffrida
0f353411d7 Set IPC status code only for RECEIVE 2010-04-26 14:43:59 +00:00
Tomas Hruby
b4cf88a04f Userspace scheduling
- cotributed by Bjorn Swift

- In this first phase, scheduling is moved from the kernel to the PM
  server. The next steps are to a) moving scheduling to its own server
  and b) include useful information in the "out of quantum" message,
  so that the scheduler can make use of this information.

- The kernel process table now keeps record of who is responsible for
  scheduling each process (p_scheduler). When this pointer is NULL,
  the process will be scheduled by the kernel. If such a process runs
  out of quantum, the kernel will simply renew its quantum an requeue
  it.

- When PM loads, it will take over scheduling of all running
  processes, except system processes, using sys_schedctl().
  Essentially, this only results in taking over init. As children
  inherit a scheduler from their parent, user space programs forked by
  init will inherit PM (for now) as their scheduler.

 - Once a process has been assigned a scheduler, and runs out of
   quantum, its RTS_NO_QUANTUM flag will be set and the process
   dequeued. The kernel will send a message to the scheduler, on the
   process' behalf, informing the scheduler that it has run out of
   quantum. The scheduler can take what ever action it pleases, based
   on its policy, and then reschedule the process using the
   sys_schedule() system call.

- Balance queues does not work as before. While the old in-kernel
  function used to renew the quantum of processes in the highest
  priority run queue, the user-space implementation only acts on
  processes that have been bumped down to a lower priority queue.
  This approach reacts slower to changes than the old one, but saves
  us sending a sys_schedule message for each process every time we
  balance the queues. Currently, when processes are moved up a
  priority queue, their quantum is also renewed, but this can be
  fiddled with.

- do_nice has been removed from kernel. PM answers to get- and
  setpriority calls, updates it's own nice variable as well as the
  max_run_queue. This will be refactored once scheduling is moved to a
  separate server. We will probably have PM update it's local nice
  value and then send a message to whoever is scheduling the process.

- changes to fix an issue in do_fork() where processes could run out
  of quantum but bypassing the code path that handles it correctly.
  The future plan is to remove the policy from do_fork() and implement
  it in userspace too.
2010-03-29 11:07:20 +00:00
Cristiano Giuffrida
bde2109b7c IPC status code for receive().
IPC changes:
- receive() is changed to take an additional parameter, which is a pointer to
a status code.
- The status code is filled in by the kernel to provide additional information
to the caller. For now, the kernel only fills in the IPC call used by the
sender.

Syslib changes:
- sef_receive() has been split into sef_receive() (with the original semantics)
and sef_receive_status() which exposes the status code to userland.
- Ideally, every sys process should gradually switch to sef_receive_status()
and use is_ipc_notify() as a dependable way to check for notify.
- SEF has been modified to use is_ipc_notify() and demonstrate how to use the
new status code.
2010-03-23 00:09:11 +00:00
Tomas Hruby
a972f4bacc All macros defining rts flags are prefixed with RTS_
- macros used with RTS_SET group of macros to define struct proc p_rts_flags are
  now prefixed with RTS_ to make things clear
2009-11-10 09:11:13 +00:00
David van Moolenbroek
e538509508 Kernel: remove unused CHECK_DEADLOCK definition 2009-09-07 20:23:31 +00:00
Ben Gras
c078ec0331 Basic VM and other minor improvements.
Not complete, probably not fully debugged or optimized.
2008-11-19 12:26:10 +00:00
Philip Homburg
f41429d815 Cleanup. 2007-04-23 13:44:56 +00:00
Ben Gras
55bdde85f0 Hack out of proc.c; function and flags width in ipc.h back to nibbles
instead of bytes for backwards compatability
2006-03-15 11:29:54 +00:00
Jorrit Herder
021e3234d8 Jorrit's ... "progress?" 2006-03-10 16:10:05 +00:00
Jorrit Herder
b16a88692a New deadlock check at proc.c.
New exit checks (stop IPC).
2005-10-12 15:08:23 +00:00
Ben Gras
5ae6f98dea Andy's formatting fixes. 2005-09-11 16:44:06 +00:00
Ben Gras
d11b2e4b8c Al's double-blank-line removal request 2005-08-22 15:23:47 +00:00
Jorrit Herder
e561081545 Miscellaneous clean ups and fixes to the kernel.
Support for FLOPPY in boot image. (Set controller=fd at boot monitor.)
Moved major device numbers to <minix/dmap.h> (maybe rename to dev.h?)
2005-08-04 09:26:36 +00:00
Jorrit Herder
89cf745fe2 Single boot driver loaded, while multiple can be included in the boot image.
The user needs to set label=... to choose the driver of his or her choice.
This driver will be mapped onto the controller that is set in controller=...

Minor cleanup of kernel source code (boot image table now is static).
2005-08-03 16:06:35 +00:00
Jorrit Herder
1f450f4959 Test .. no update. 2005-08-03 08:15:36 +00:00
Jorrit Herder
b69ca94efb Fixed 'bug' in log driver that caused kernel messages not to be displayed.
This was caused by a change in the shared driver code. Not log's fault.

Renamed #definitions of driver process numbers, e.g., TTY now is TTY_PROC_NR.
All known (special) processes now have consistent naming scheme. Kernel tasks
don't follow this scheme.
2005-08-03 08:14:08 +00:00
Jorrit Herder
ab7c0a9926 Cleaned up table. Moved policies to table.
Small fixes to do_copy, do_privctl and do_fork.
2005-08-02 15:28:09 +00:00
Jorrit Herder
0946d128cd - Kernel call handlers cleaned up. More strict checking of input parameters.
- Moved generic_handler() from system.c to system/do_irqctl.c.
- Set privileges of system processes somewhat stricter.
2005-07-29 15:26:23 +00:00
Jorrit Herder
fe0dcb5c00 AT driver is not modified (debugging only);
TTY: select and revive with new notify and FS call back;
kernel: removed old notify code; removed ugly prepare_shutdown timer
kputc: don't send to FS if PRINTF_PROC fails
2005-07-27 14:32:16 +00:00
Jorrit Herder
a41eb700e8 Minor fixes and improvements for sys_call(). 2005-07-26 13:51:21 +00:00
Jorrit Herder
8866b4d0ef Kernel changes:
- reinstalled priority changing, now in sched() and unready()
- reinstalled check on message buffer in sys_call()
- reinstalled check in send masks in sys_call()
- changed do_fork() to get new privilege structure for SYS_PROCs
- removed some processes from boot image---will be dynamically started later
2005-07-26 12:48:34 +00:00
Jorrit Herder
198c976f7e System processes can be signaled; signals are transformed in SYS_EVENT message
that passes signal map along. This mechanisms is also used for nonuser signals
like SIGKMESS, SIGKSTOP, SIGKSIG.

Revised comments of many system call handlers. Renamed setpriority to nice.
2005-07-19 12:21:36 +00:00
Jorrit Herder
42ab148155 Reorganized system call library; uses separate file per call now.
New configuration header file to include/ exclude functionality.
Extracted privileged features from struct proc and create new struct priv.
Renamed various system calls for readability.
2005-07-14 15:12:12 +00:00
Jorrit Herder
ec24a0798c Updated function key mapping because of possible changes to NOTIFY.
The TTY driver now only notifies the IS server about function key event,
but does not tell which keys are pressed. The IS servers queries the TTY
driver to find out about this.
2005-06-20 14:23:31 +00:00
Jorrit Herder
0e2a7a9730 Kernel cleanup.
Reduced kernel size by 512KB by moving private buffer into cstart() function.
Replaced assertions with erroneous return values. Removed assertions relating
to isuserp(rp), since all processes should become user processes; system
processes are now treated similar to other processes.
2005-06-07 12:34:25 +00:00
Jorrit Herder
322ec9ef8b Moved stime, time, times POSIX calls from FS to PM. Removed child time
accounting from kernel (now in PM).  Large amount of files in this commit
is due to system time problems during development.
2005-05-31 09:50:51 +00:00
Jorrit Herder
8d9c0886cd Created ECHO system call for testing purposes.
Furthermore, a quick way to get one's own process number.
2005-05-27 13:57:00 +00:00