reworking of inpcbinfo locking:
(1) Convert inpcb reference counting from manually manipulated integers to
the refcount(9) KPI. This allows the refcount to be managed atomically
with an inpcb read lock rather than write lock, or even with no inpcb
lock at all. As a result, in_pcbref() also no longer requires an inpcb
lock, so can be performed solely using the lock used to look up an
inpcb.
(2) Shift more inpcb freeing activity from the in_pcbrele() context (via
in_pcbfree_internal) to the explicit in_pcbfree() context. This means
that the inpcb refcount is increasingly used only to maintain memory
stability, not actually defer the clean up of inpcb protocol parts.
This is desirable as many of those protocol parts required the pcbinfo
lock, which we'd like not to acquire in in_pcbrele() contexts. Document
this in comments better.
(3) Introduce new read-locked and write-locked in_pcbrele() variations,
in_pcbrele_rlocked() and in_pcbrele_wlocked(), which allow the inpcb to
be properly unlocked as needed. in_pcbrele() is a wrapper around the
latter, and should probably go away at some point. This makes it
easier to use this weak reference model when holding only a read lock,
as will happen in the future.
This may well be safe to MFC, but some more KBI analysis is required.
Reviewed by: bz
MFC after: 3 weeks
Sponsored by: Juniper Networks, Inc.
in_pcb_lport(), in_pcblookup_local(), and in_pcblookup_hash(), and similarly
for IPv6 functions. In the future, we would like to support other flags
relating to locking strategy.
This change doesn't appear to modify the KBI in practice, as callers already
passed in INPLOOKUP_WILDCARD rather than a simple boolean.
MFC after: 3 weeks
Reviewed by: bz
Sponsored by: Juniper Networks, Inc.
(1) Add a locking guide for inpcbinfo.
(2) Annotate inpcbinfo fields with synchronisation information; not all
annotations are 100% satisfactory.
(3) Reorder inpcbinfo fields so that the lock is at the head of the
structure, and close to fields it protects.
(4) Sort fields that will eventually be hashlock/pcbgroup-related together
even though they remain locked by ipi_lock for now.
Reviewed by: bz
Sponsored by: Juniper Networks
X-MFC after: KBI analysis required
When we are operating on a symbolic link pointing to an existing
file, bail out by default, but go ahead if -f is specified.
Submitted by: arundel
MFC after: 2 weeks
Increase the size of cg_count in order to enable usage of > 127 CPUs.
cg_children is also bumped in order to keep the structure naturally
padded, even if this is not strictly necessary.
Submitted and tested by: sbruno
Rewrite atomic operations for powerpc in order to achieve the following:
- Produce a type-clean implementation (in terms of functions arguments
and returned values) for the primitives.
- Fix errors with _long() atomics where they ended up with the wrong
arguments to be accepted.
- Follow the sys/type.h specifics that define the numbered types starting
from standard C types.
- Let _ptr() version to not auto-magically cast arguments, but leave
the burden on callers, as _ptr() atomic is intended to be used
relatively rarely.
Fix cfi in order to support the latest point.
In collabouration with: bde
Tested by: andreast, nwhitehorn, jceel
MFC after: 2 weeks
wihtout updating world (good transition aide for -current, but also
allows kernels to be built on -stable the old way too). This likely
should go away around FreeBSD 10.0 or so.
WITH{OUT,}_KERNEL_SYMBOLS (defaulting to WITH). In the fullness of
time, likely around 2020, INSTALL_NODEBUG will be removed. For now,
don't print a warning when using INSTALL_NODEBUG, but that will be
coming soon.
similar to what we do for binutils. When clang's default triple starts
with 'amd64-', it does not pass a proper -target-cpu option to its
first stage.
This can lead to problems, for example when structs are memcpy'd, and
clang erroneously assumes they are 16-byte aligned. It will then use
the 'movaps' SSE instruction to implement the copy, which results in a
bus error if the struct is really 8-byte aligned.
I encountered this issue when gcc's /usr/libexec/cc1 started crashing
with SIGBUS, after rebuilding world with clang ToT, but it also affects
the version of clang that we have in the tree. We were just lucky until
now, apparently. :)
If the length of a directory in PATH together with the given filename
exceeded FILENAME_MAX (which may happen even for pathnames that work), a
static buffer was overflown.
The static buffer is unnecessary, we can use the stalloc() stack.
Obtained from: NetBSD
MFC after: 1 week
method, so that callers can indicate the minimum vnode
locking requirement. This will allow some file systems to choose
to return a LK_SHARED locked vnode when LK_SHARED is specified
for the flags argument. This patch only adds the flag. It
does not change any file system to use it and all callers
specify LK_EXCLUSIVE, so file system semantics are not changed.
Reviewed by: kib
uma_startup2() was called. Thus, setting the variable "booted" to true in
uma_startup() was ok on machines with UMA_MD_SMALL_ALLOC defined, because
any allocations made after uma_startup() but before uma_startup2() could be
satisfied by uma_small_alloc(). Now, however, some multipage allocations
are necessary before uma_startup2() just to allocate zone structures on
machines with a large number of processors. Thus, a Boolean can no longer
effectively describe the state of the UMA allocator. Instead, make "booted"
have three values to describe how far initialization has progressed. This
allows multipage allocations to continue using startup_alloc() until
uma_startup2(), but single-page allocations may begin using
uma_small_alloc() after uma_startup().
2. With the aforementioned change, only a modest increase in boot pages is
necessary to boot UMA on a large number of processors.
3. Retire UMA_MD_SMALL_ALLOC_NEEDS_VM. It has only been used between
r182028 and r204128.
Reviewed by: attilio [1], nwhitehorn [3]
Tested by: sbruno
This reflects failure to determine the pathname of the new directory in the
exit status (1). Normally, cd returns successfully if it did chdir() and the
call was successful.
In POSIX, -e only has meaning with -P; because our -L is not entirely
compliant and may fall back to -P mode, -e has some effect with -L as well.
which is now disabled by default. The detection is known to cause hangs
on boot with some new Lenovo laptops on FreeBSD/amd64.
Reported by: gnn
Discussed with: jkim
MFC after: 3 months
interface is brought down, even though the interface address is still
valid. This patch maintains the permanent ARP entries as long as the
interface address (having the same prefix as that of the ARP entries)
is valid.
Reviewed by: delphij
MFC after: 5 days
not true on old PCI based controllers. DAC configuration is read
from EEPROM in device reset phase and driver can override DAC
configuration. However I guess there is an undocumented reason why
EEPROM configuration does not enable DAC so do not blindly override
DAC configuration. Recent PCIe based controllers are supposed to
support 64bit DMA so allow 64bit DMA only on PCIe based controllers.
PR: kern/157184
MFC after: 1 week
