- struct plimit includes a mutex to protect a reference count. The plimit
structure is treated similarly to struct ucred in that is is always copy
on write, so having a reference to a structure is sufficient to read from
it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
limits from a process to keep the limit structure from changing out from
under you while reading from it.
- Various global limits that are ints are not protected by a lock since
int writes are atomic on all the archs we support and thus a lock
wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
either an rlimit, or the current or max individual limit of the specified
resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
(it didn't used the stackgap when it should have) but uses lim_rlimit()
and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits. It
also no longer uses the stackgap for accessing sysctl's for the
ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result,
ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.
Submitted by: mtm (mostly, I only did a few cleanups and catchups)
Tested on: i386
Compiled on: alpha, amd64
machdep.c fixed the missing early initialization of curpcb, so curpcb
is now always set together with curthread and it cannot be NULL except
before the IDT has been set up (so trap() is unreachable) or after a
memory error. In any case, it was often used without checking.
curcpb shouldn't exist anyway. It doesn't exist for most non-i386 arches.
It just caches curthread->td_pcb in a global. This was a better idea
before it was per-cpu. trap() and some other places can get at it more
efficiently using td->td_pcb instead of PCPU_GET(curpcb). The main
exception is support.s which mostly wants only curpcb->pcb_onfault.
the thread that calls pmap_pte_quick() and by virtue of the page queues
lock being held, we can manage PADDR1/PMAP1 as a CPU private mapping.
The most common effect of this change is to reduce the overhead of the page
daemon on multiprocessors.
In collaboration with: tegge
every system call, and that grabs and release the process lock each
time. Don't fix it (yet), but document it so we know to fix it.
Also should be a 5.3-RELEASE todo item.
can look at the ACPI tables. If the startup fails, we panic and tell the
user to try rebooting with ACPI disabled. Previously in this case we
would try to use $PIR interrupt routing which only works for the atpic
while using the apic to handle interrupts which would result in misrouted
interrupts and a hang at boot time with no error message.
- Read the SCI out of the FADT instead of hardcoding 9 when checking to see
if an interrupt override entry is for the SCI.
- Try to work around some BIOS brain damage for the SCI's programming by
forcing the SCI to be level triggered and active low if it is routed
to a non-ISA interrupt (greater than 15) or if it is identity mapped with
edge trigger and active high polarity. This should fix some of the hangs
with device apic and ACPI that some people see.
Reviewed by: njl
than the switchin functions to guarantee that we're operating with the
correct tlb entry.
- Remove the post copy/zero tlb invalidations. It is faster to invalidate
an entry that is known to exist and so it is faster to invalidate after
use. However, some architectures implement speculative page table
prefetching so we can not be guaranteed that the invalidated entry is still
invalid when we re-enter any of these functions. As a result of this we
must always invalidate before use to be safe.
a deadlock in several years. Furthermore, the IPI code is currently
protected by a seperate spinlock. This only served to make IPIs twice as
expensive as they had to be which severely slowed down the IPI heavy ULE
scheduler.
Suggested by: nate
- get rid of "magick" values in code and make sysctl's reflecting reality
on processor versions which have one or another frequency "forbidden"
due to errata.
MFC after: 2 weeks
Suggested by: nate
- get rid of "magick" values in code and make sysctl's reflecting reality
on processor versions which have one or another frequency "forbidden"
due to errata.
PR:
Submitted by:
Reviewed by:
Approved by:
Obtained from:
MFC after: 2 weeks
rev.1.1040. It is a miscellaneous isa+pci driver, but came back
described as a pci-only driver and placed in an i4b pci subsection
after its migration to /sys/conf/NOTES. Put it back where it used to
be, fully unsorted in the `Miscellaneous hardware' section. Reduced
nearby disorder in this section by moving configuration of the digi
driver to where it was for the old digiboard drivers, so that the
order at least matches the order in the table of contents.
- references to removed math emulators for NPX_DEBUG
- header for the null set of mandatory devices
- reference to the removed (and bogus when it existed) sysctl
kern.timecounter.method.
FIxed some nearby disorder (descriptions of CPU_BLUELIGHTNING_3X,
CPU_DIRECT_MAPPED_CACHE, CPU_DISABLE_CMPXCHG, CPU_DISABLE_SSE,
CPU_ELAN_XTAL and CPU_SOEKRIS, and options for all of these except
CPU_DIRECT_MAPPED_CACHE).
CPU_ENABLE_TCC enables Thermal Control Circuitry (TCC) found in some
Pentium(tm) 4 and (possibly) later CPUs. When enabled and detected,
TCC allows to restrict power consumption by using machdep.cpuperf*
sysctls. This operates independently of SpeedStep and is useful on
systems where other mechanisms such as apm(4) or acpi(4) don't work.
Given the fact that many, even modern, notebooks don't work properly
with Intel ACPI, this is indeed very useful option for notebook owners.
Obtained from: OpenBSD
MFC after: 2 weeks
CPU_ENABLE_TCC enables Thermal Control Circuitry (TCC) found in some
Pentium(tm) 4 and (possibly) later CPUs. When enabled and detected,
TCC allows to restrict power consumption by using machdep.cpuperf*
sysctls. This operates independently of SpeedStep and is useful on
systems where other mechanisms such as apm(4) or acpi(4) don't work.
Given the fact that many, even modern, notebooks don't work properly
with Intel ACPI, this is indeed very useful option for notebook owners.
Obtained from: OpenBSD
MFC after: 2 weeks
at it, use the ANSI C generic pointer type for the second argument,
thus matching the documentation.
Remove the now extraneous (and now conflicting) function declarations
in various libc sources. Remove now unnecessary casts.
Reviewed by: bde
replacement of struct proc by struct thread. This bug could cause a
NULL pointer dereferencation under certain circumstances (e. g. while
running /etc/rc.d/pcvt).
Put a CTASSERT() on the size of the struct.
Use the struct where it is easy to do so in elan_mmcr.c
Add the Elan specific hardware reset code (also from jb@).
Make sigaltstack as per-threaded, because per-process sigaltstack state
is useless for threaded programs, multiple threads can not share same
stack.
The alternative signal stack is private for thread, no lock is needed,
the orignal P_ALTSTACK is now moved into td_pflags and renamed to
TDP_ALTSTACK.
For single thread or Linux clone() based threaded program, there is no
semantic changed, because those programs only have one kernel thread
in every process.
which left out SVR4 bits.
is useless for threaded programs, multiple threads can not share same
stack.
The alternative signal stack is private for thread, no lock is needed,
the orignal P_ALTSTACK is now moved into td_pflags and renamed to
TDP_ALTSTACK.
For single thread or Linux clone() based threaded program, there is no
semantic changed, because those programs only have one kernel thread
in every process.
