Commit graph

244 commits

Author SHA1 Message Date
Arun Thomas
daa14edc0d kernel: make clang-buildable 2011-06-28 15:34:19 +02:00
Arun Thomas
93ae43f577 boot: Add multiboot support
Not yet fully spec-compliant; work in progress
2011-06-24 17:21:51 +02:00
Ben Gras
e785381d4d introduce option to time assert()s
. remove a few asserts in the kernel and 64bi library
    that are not compatible with the timing code
  . change the TIME_BLOCKS code a little to work in-kernel
2011-06-24 16:00:42 +02:00
Ben Gras
a77c2973b3 fix clang warnings -R in kernel/ and servers/ 2011-06-09 16:09:13 +02:00
Erik van der Kouwe
b08dff6011 Remove unused duplicate grant code in umap 2011-06-09 05:06:34 +00:00
Tomas Hruby
423be1545c Fix for SPROFILE == 0
- contributed by Antoine Leca
2011-05-25 09:42:11 +02:00
Arun Thomas
350b60661a ELF multiboot support 2011-05-04 18:51:43 +02:00
Erik van der Kouwe
e969b5e11b Remote unused segctl kernel call 2011-04-26 23:28:23 +02:00
Ben Gras
2b09bfde6d kernel: fix logic error in the case vm_lookup fails 2011-04-20 10:17:08 +00:00
Tomas Hruby
dc8ee363db SMP - INIT IPI deasserting fix
When deasserting the INIT IPI the DM field must be zero
2011-04-13 16:57:43 +00:00
David van Moolenbroek
c51cd5fe91 Server/driver protocols: no longer allow third-party copies.
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.
2011-04-11 17:35:05 +00:00
Tomas Hruby
8200e91073 Fixed smp compilation
- missing u64.h include after 64bit routines for gcc got inlined
2011-04-08 11:52:30 +00:00
Erik van der Kouwe
03a7d0e8ae Add cttybaud boot monitor variable to control speed of serial console (combine with ctty 0) 2011-03-16 12:25:10 +00:00
Arun Thomas
25a790a631 VM and kernel support for ELF 2011-02-26 23:00:55 +00:00
Ben Gras
07bfb4f4e4 kernel - account for kernel cpu time (ipc, kcalls) in caller 2011-02-08 13:58:32 +00:00
Arun Thomas
aaaad89244 Use int64 functions consistently
Instead of manipulating the u64_t type directly, use the
ex64hi()/ex64lo()/make64() functions.
2010-11-07 23:35:29 +00:00
Ben Gras
515e8d075f kernel: limit stacktrace depth to 50.
- Unlikely to discard useful information and avoids long
    system lockups on machines configured to print system output to serial.
2010-11-02 21:27:04 +00:00
Tomas Hruby
c9bfb13cdb Kernel keeps information about each cpu
- kernel maintains a cpu_info array which contains various
  information about each cpu as filled when each cpu boots

- the information contains idetification, features etc.
2010-10-26 21:07:27 +00:00
Tomas Hruby
9e01a83636 SMP - reduced TLB flushing
- flush TLB of processes only if the page tables has been changed and
  the page tables of this process are already loaded on this cpu which
  means that there might be stale entries in TLB. Until now SMP was
  always flushing TLB to make sure everything is consistent.
2010-10-25 16:21:23 +00:00
Tomas Hruby
98c93e76d7 Zero no more hardwired as BSP apic id
- the BSP apic id is written in the io apic redirection entries to
  deliver the interrupts to BSP
2010-10-21 17:07:07 +00:00
Tomas Hruby
a1eefc013e single shot timer interrupts fix
- accidentaly this wasn't part of the SMP merge and the implementation
  remained uncomplete with the timer keeping ticking periodically

- APIC timer is set for a signel shot and restarted everytime it
  expires. This way we can keep the AP's trully idle

- the timer is restarted a little later before leaving to userspace

- LAPIC_TIMER_ICR is written before LAPIC_LVTTR so the newest value is
  used
2010-10-21 17:07:01 +00:00
Tomas Hruby
ebbc730fc3 spurious and error interrupt apic handlers
- fixed spurious and error interrupt handlers

- not to hog the system the warning isn't reported every time, just
  once every 100 times, similarly for the spurious PIC interrupts
2010-10-19 17:07:21 +00:00
Tomas Hruby
f42b90806a BSP apic id
- BSP apic id used uninitialized causes problems
2010-10-19 17:07:19 +00:00
Tomas Hruby
e6b1a30a26 panic in dummy apic handlers
- as panic can do the same as printf now, let's rather panic when a
  dummy apic interrupt vector handler is hit
2010-10-19 17:07:17 +00:00
Tomas Hruby
2419ab589d Fixed BKL statistics 2010-10-19 17:07:11 +00:00
Tomas Hruby
8145b458d6 A klib.S include fix
- by Antoine Leca
2010-10-15 22:21:01 +00:00
Tomas Hruby
1786291e32 Watchdog and kernel profiling for AMD
- a different set of MSRs and performance counters is used on AMD

- when initializing NMI watchdog the test for Intel architecture
  performance counters feature only applies to Intel now

- NMI is enabled if the CPU belongs to a family which has the
  performance counters that we use
2010-09-23 14:42:30 +00:00
Tomas Hruby
8eece1c00c CPU type detection
- sometimes the system needs to know precisely on what type of cpu is
  running. The cpu type id detected during arch specific
  initialization and kept in the machine structure for later use.

- as a side-effect the information is exported to userland
2010-09-23 14:42:19 +00:00
Tomas Hruby
ef92583c3a Busy idle loop when profiling
- the Intel architecture cycle counter (performance counter) does not
  count when the CPU is idle therefore we use busy loop instead of
  halting the cpu when there is nothing to schedule

- the downside is that handling interrupts may be accounted as idle
  time if a sample is taken before we get out of the nested trap and
  pick a new process
2010-09-23 10:49:52 +00:00
Tomas Hruby
e63b85a50b NMI sampling
- if profile --nmi kernel uses NMI watchdog based sampling based on
  Intel architecture performance counters

- using NMI makes kernel profiling possible

- watchdog kernel lockup detection is disabled while sampling as we
  may get unpredictable interrupts in kernel and thus possibly many
  false positives

- if watchdog is not enabled at boot time, profiling enables it and
  turns it of again when done
2010-09-23 10:49:45 +00:00
Ben Gras
82d576c9ca enable_fpu_exception() - only write cr0 if bit isn't already on.
(NMI profiling results indicate this both is relatively expensive and
happens a lot unnecessarily if the fpu is in use.)
2010-09-22 14:31:06 +00:00
Tomas Hruby
2d1c8849d8 Remove unnecessary TLB flushes
- this should be only for SMP
2010-09-22 08:01:36 +00:00
Tomas Hruby
08bf4dec4f Fixed comments in watchdog 2010-09-19 23:23:44 +00:00
Tomas Hruby
e9ecba9fc7 fix - forgotten debug print 2010-09-19 15:54:31 +00:00
Tomas Hruby
a665ae3de1 Userspace scheduling - exporting stats
- contributed by Bjorn Swift

- adds process accounting, for example counting the number of messages
  sent, how often the process was preemted and how much time it spent
  in the run queue. These statistics, along with the current cpu load,
  are sent back to the user-space scheduler in the Out Of Quantum
  message.

- the user-space scheduler may choose to make use of these statistics
  when making scheduling decisions. For isntance the cpu load becomes
  especially useful when scheduling on multiple cores.
2010-09-19 15:52:12 +00:00
Tomas Hruby
13bda81ee0 Fixed FPU for single cpu 2010-09-16 09:51:45 +00:00
Tomas Hruby
72cc01ff48 apic_timer_x
- set the apic_timer_x factor variable to slowdown apic timer in
  virtual machines
2010-09-16 07:18:47 +00:00
Tomas Hruby
5b8b623765 SMP - lazy FPU
- when a process is migrated to a different CPU it may have an active
  FPU context in the processor registers. We must save it and migrate
  it together with the process.
2010-09-15 14:11:25 +00:00
Tomas Hruby
1f89845bb2 SMP - can boot even if some cpus fail to boot
- EBADCPU is returned is scheduler tries to run a process on a CPU
  that either does not exist or isn't booted

- this change was originally meant to deal with stupid cpuid
  instruction which provides totally useless information about
  hyper-threading and MPS which does not deal with ht at all. ACPI
  provides correct information. If ht is turned off it looks like some
  CPUs failed to boot.  Nevertheless this patch may be handy for
  testing/benchmarking in the future.
2010-09-15 14:11:21 +00:00
Tomas Hruby
421f324baa SMP - Make sure that VM does not change pt of a process while kernel copies 2010-09-15 14:11:19 +00:00
Tomas Hruby
e4283176ae SMP - Force TLB flush before scheduling a process
- this makes sure that each process always run with updated TLB

- this is the simplest way how to achieve the consistency. As it means
  significant performace degradation when not require, this is nto the
  final solution and will be refined
2010-09-15 14:11:17 +00:00
Tomas Hruby
e2701da5a9 SMP - Single shot local timer
- APIC timer always reprogrammed if expired

- timer tick never happens when in kernel => never immediate return
  from userspace to kernel because of a buffered interrupt

- renamed argument to lapic_set_timer_one_shot()

- removed arch_ prefix from timer functions
2010-09-15 14:11:06 +00:00
Tomas Hruby
e87d29171f SMP - Compiles for both single and multi processor again
- this patch adds various fixes as some of the previous patches break
  compilations without CONFIG_SMP being set
2010-09-15 14:11:03 +00:00
Tomas Hruby
454589debd SMP - Print cpu of the process
- adds '4' to print processes assigned to each cpu without printing
  the process it is blocked on (a lightweight '1')
2010-09-15 14:11:01 +00:00
Tomas Hruby
0ac9b6d4cf SMP - trully idle APs
- any cpu can use smp_schedule() to tell another cpu to reschedule

- if an AP is idle, it turns off timer as there is nothing to
  preempt, no need to wakeup just to go back to sleep again

- if a cpu makes a process runnable on an idle cpu, it must wake it up
  to reschedule
2010-09-15 14:10:57 +00:00
Tomas Hruby
387e1835d1 SMP - BSP halts APs before shutting down 2010-09-15 14:10:54 +00:00
Tomas Hruby
c554aef0e1 SMP - BKL statistics
- pressing 'B' on the serial cnsole prints statistics for BKL per cpu.

- 'b' resets the counters

- it presents number of cycles each CPU spends in kernel, how many
  cycyles it spends spinning while waiting for the BKL

- it shows optimistic estimation in how many cases we get the lock
  immediately without spinning. As the test is not atomic the lock may
  be already held by some other cpu before we actually try to acquire
  it.
2010-09-15 14:10:37 +00:00
Tomas Hruby
93b9873a56 SMP - Free PDE slots are split among CPU
- cross-address space copies use these slots to map user memory for
  kernel. This avoid any collisions between CPUs

- well, we only have a single CPU running at a time, this is just to
  be safe for the future
2010-09-15 14:10:36 +00:00
Tomas Hruby
9e12630d75 SMP - APs are fully enabled
- apic_send_ipi() to send inter-processor interrupts (IPIs)

- APIC IPI schedule and halt handlers to signal x-cpu that a cpu shold
  reschedule or halt

- various little changes to let APs run

- no processes are scheduled at the APs and therefore they are idle
  except being interrupted by a timer time to time
2010-09-15 14:10:30 +00:00
Tomas Hruby
d37b7ebc0b SMP - CPU local cycles accounting
- tsc_ctr_switch is made cpu local

- although an x86 specific variable it must be declared globaly as the
  cpulocal implementation does not allow otherwise
2010-09-15 14:10:27 +00:00