sf buf allocation, use wakeup() instead of wakeup_one() to notify sf
buffer waiters about free buffer.
sf_buf_alloc() calls msleep(PCATCH) when SFB_CATCH flag was given,
and for simultaneous wakeup and signal delivery, msleep() returns
EINTR/ERESTART despite the thread was selected for wakeup_one(). As
result, we loose a wakeup, and some other waiter will not be woken up.
Reported and tested by: az
Reviewed by: alc, jhb
MFC after: 1 week
table. The 'locked' attribute is used to circumvent the regular page table
locking for some special pages, with the result that including locked pages
here causes races when updating the stats.
logic to support modifying the page table through a hypervisor. This
uses KOBJ inheritance to provide subclasses of the base 64-bit AIM MMU
class with additional methods for page table manipulation.
Many thanks to Peter Grehan for suggesting this design and implementing
the MMU KOBJ inheritance mechanism.
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files. A better long-term solution is
still being considered. This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.
Changes reverted:
------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines
Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.
------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines
Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines
Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.
that causes AP bringup to fail if some of the Cell HID-register code
is anywhere in the instruction stream. Pending a better solution, cache
performance on SMP Cell systems running without a hypervisor will be
suboptimal.
mappings need to end up in the kernel anyway since the kernel begins
executing in OF context. Separating them adds needless complexity,
especially since the powerpc64 and mmu_oea64 code gave up on it a long
time ago.
As a side effect, the PPC ofw_machdep code is no longer AIM-specific,
so move it to powerpc/ofw.
hypervisor infrastructure support:
- Fix coexistence of multiple platform modules in the same kernel
- Allow platform modules to provide an SMP topology
- PowerPC hypervisors limit the amount of memory accessible in real mode.
Allow the platform modules to specify the maximum real-mode address,
and modify the bits of the kernel that need to allocate
real-mode-accessible buffers to respect this limits.
work properly with single-stepping in a kernel debugger. Specifically,
these routines have always disabled interrupts before increasing the nesting
count and restored the prior state of interrupts after decreasing the nesting
count to avoid problems with a nested interrupt not disabling interrupts
when acquiring a spin lock. However, trap interrupts for single-stepping
can still occur even when interrupts are disabled. Now the saved state of
interrupts is not saved in the thread until after interrupts have been
disabled and the nesting count has been increased. Similarly, the saved
state from the thread cannot be read once the nesting count has been
decreased to zero. To fix this, use temporary variables to store interrupt
state and shuffle it between the thread's MD area and the appropriate
registers.
In cooperation with: bde
MFC after: 1 month
only, and should be protected with an ifdef, and the no-execute bit in
32-bit set_user_sr() should be set before the comparison, not after, or
it will never match.
set_user_sr() itself caches the user segment VSID, there is no need for
cpu_switch() to do it again. This change also unifies the 32 and 64-bit
code paths for kernel faults on user pages and remaps the user SLB slot
on 64-bit systems when taking a syscall to avoid some unnecessary segment
exception traps.
concurrency bug. Since all SLB/SR entries were invalidated during an
exception, a decrementer exception could cause the user segment to be
invalidated during a copyin()/copyout() without a thread switch that
would cause it to be restored from the PCB, potentially causing the
operation to continue on invalid memory. This is now handled by explicit
restoration of segment 12 from the PCB on 32-bit systems and a check in
the Data Segment Exception handler on 64-bit.
While here, cause copyin()/copyout() to check whether the requested
user segment is already installed, saving some pipeline flushes, and
fix the synchronization primitives around the mtsr and slbmte
instructions to prevent accessing stale segments.
MFC after: 2 weeks
values to zero. A correct solution would involve emulating vector
operations on denormalized values, but this has little effect on accuracy
and is much less complicated for now.
MFC after: 2 weeks
by just caching the mode for later use by pmap_enter(), following amd64.
While here, correct some mismerges from mmu_oea64 -> mmu_oea and clean
up some dead code found while fixing the fictitious page behavior.
which are similar to the previous ones, and one for user maps, which
are arrays of pointers into the SLB tree. This changes makes user SLB
updates atomic, closing a window for memory corruption. While here,
rearrange the allocation functions to make context switches faster.
hardware with a lockless sparse tree design. This marginally improves
the performance of PMAP and allows copyin()/copyout() to run without
acquiring locks when used on wired mappings.
Submitted by: mdf
include/mmuvar.h - Change the MMU_DEF macro to also create the class
definition as well as define the DATA_SET. Add a macro, MMU_DEF_INHERIT,
which has an extra parameter specifying the MMU class to inherit methods
from. Update the comments at the start of the header file to describe the
new macros.
booke/pmap.c
aim/mmu_oea.c
aim/mmu_oea64.c - Collapse mmu_def_t declaration into updated MMU_DEF macro
The MMU_DEF_INHERIT macro will be used in the PS3 MMU implementation to
allow it to inherit the stock powerpc64 MMU methods.
Reviewed by: nwhitehorn
The main goal of this is to generate timer interrupts only when there is
some work to do. When CPU is busy interrupts are generating at full rate
of hz + stathz to fullfill scheduler and timekeeping requirements. But
when CPU is idle, only minimum set of interrupts (down to 8 interrupts per
second per CPU now), needed to handle scheduled callouts is executed.
This allows significantly increase idle CPU sleep time, increasing effect
of static power-saving technologies. Also it should reduce host CPU load
on virtualized systems, when guest system is idle.
There is set of tunables, also available as writable sysctls, allowing to
control wanted event timer subsystem behavior:
kern.eventtimer.timer - allows to choose event timer hardware to use.
On x86 there is up to 4 different kinds of timers. Depending on whether
chosen timer is per-CPU, behavior of other options slightly differs.
kern.eventtimer.periodic - allows to choose periodic and one-shot
operation mode. In periodic mode, current timer hardware taken as the only
source of time for time events. This mode is quite alike to previous kernel
behavior. One-shot mode instead uses currently selected time counter
hardware to schedule all needed events one by one and program timer to
generate interrupt exactly in specified time. Default value depends of
chosen timer capabilities, but one-shot mode is preferred, until other is
forced by user or hardware.
kern.eventtimer.singlemul - in periodic mode specifies how much times
higher timer frequency should be, to not strictly alias hardclock() and
statclock() events. Default values are 2 and 4, but could be reduced to 1
if extra interrupts are unwanted.
kern.eventtimer.idletick - makes each CPU to receive every timer interrupt
independently of whether they busy or not. By default this options is
disabled. If chosen timer is per-CPU and runs in periodic mode, this option
has no effect - all interrupts are generating.
As soon as this patch modifies cpu_idle() on some platforms, I have also
refactored one on x86. Now it makes use of MONITOR/MWAIT instrunctions
(if supported) under high sleep/wakeup rate, as fast alternative to other
methods. It allows SMP scheduler to wake up sleeping CPUs much faster
without using IPI, significantly increasing performance on some highly
task-switching loads.
Tested by: many (on i386, amd64, sparc64 and powerc)
H/W donated by: Gheorghe Ardelean
Sponsored by: iXsystems, Inc.
This reflects actual type used to store and compare child device orders.
Change is mostly done via a Coccinelle (soon to be devel/coccinelle)
semantic patch.
Verified by LINT+modules kernel builds.
Followup to: r212213
MFC after: 10 days
wrong element of the VSID bitmap array to be examined after a collision,
leading to reallocation of in-use VSIDs under some circumstances, with
attendant memory corruption. Also add an assert to check for this kind of
problem in the future.
MFC after: 4 days
PowerPC CPUs running a 32-bit kernel. This bug could cause in-use VSIDs
to be allocated again to another process, causing memory space overlaps
and corruption.
Reported by: linimon
the existing code was very platform specific, and broken for SMP systems
trying to reboot from KDB.
- Add a new PLATFORM_RESET() method to the platform KOBJ interface, and
migrate existing reset functions into platform modules.
- Modify the OF_reboot() routine to submit the request by hand to avoid
the IPIs involved in the regular openfirmware() routine. This fixes
reboot from KDB on SMP machines.
- Move non-KDB reset and poweroff functions on the Powermac platform
into the relevant power control drivers (cuda, pmu, smu), instead of
using them through the Open Firmware backdoor.
- Rename platform_chrp to platform_powermac since it has become
increasingly Powermac specific. When we gain support for IBM systems,
we will grow a new platform_chrp.
