5 Commits

Author SHA1 Message Date
David van Moolenbroek
232819dd49 VFS: store process suspension state as union
Previously, VFS would use various subsets of a number of fproc
structure fields to store state when the process is blocked
(suspended) for various reasons.  As a result, there was a fair
amount of abuse of fields, hidden state, and confusion as to
which fields were used with which suspension states.

Instead, the suspension state is now split into per-state
structures, which are then stored in a union.  Each of the union's
structures should be accessed only right before, during, and right
after the fp_blocked_on field is set to the corresponding blocking
type.  As a result, it is now very clear which fields are in use
at which times, and we even save a bit of memory as a side effect.

Change-Id: I5c24e353b6cb0c32eb41c70f89c5cfb23f6c93df
2016-08-05 11:15:15 +00:00
David van Moolenbroek
1122b28691 PM: add support for saved user/group IDs
This patch aims to synchronize the basic process user and group ID
management, as well as the set[ug]id(2) and sete[ug]id(2) behavior,
with NetBSD.  As it turns out, the main issue was missing support for
saved user and group IDs.  This support is now added.

Since NetBSD's userland, which we are importing, may rely on NetBSD
specifics when it comes to security, we choose not to deviate from
NetBSD's behavior in any way here.  A new test, test89, verifies the
correct behavior - it has been confirmed to pass on NetBSD as is.

Change-Id: I023935546d97ed01ffd8090f7793d336cceb0f4a
2016-03-12 17:46:06 +01:00
David van Moolenbroek
6ad322a932 MIB: slim process tables to reduce memory usage
- About 80% of PM's process table consisted of per-signal sigaction
  structures.  This is information not used by the MIB service, and
  can safely be stored outside the main process table.

- The MIB service does not need most of the VFS process table, so VFS
  now generates a "light" version of its table upon request, with just
  the fields used by the MIB service.

The result is a size reduction of the MIB service of about 700KB.

Change-Id: I79fe7239361fbfb45286af8e86a10aed4c2d2be7
2016-01-13 20:32:55 +01:00
David van Moolenbroek
305e366fe4 ProcFS: get process information from MIB service
Instead of pulling in process tables itself, ProcFS now queries the
MIB service for process information.  This reduces ProcFS's memory
usage by about 1MB.  The change does have two negative consequences.

First, getting all the original /proc/<pid>/psinfo fields filled in
would take a lot of extra effort.  Since the only program that uses
those files at all is mtop(1), we reformat psinfo to expose only the
information used by mtop(1).  This means that with this patch, older
copies of MINIX3 ps and top will cease to work.

Second, since both MIB and ProcFS update their own view of the
process list only once per clock tick, ProcFS' view may now be
outdated by up to two clock ticks.  This is unlikely to pose a
problem in practice.

Change-Id: Iaa6b60450c8fb52d092962394d33d08bd638bc01
2016-01-13 20:32:54 +01:00
David van Moolenbroek
25d39513e7 MIB: initial tree population
Change-Id: I28ef0a81a59faaf341bfc15178df89474779a136
2016-01-13 20:32:44 +01:00