exhausted.
It is possible for a bug in the code (or, theoretically, even unusual
network conditions) to exhaust all possible mbufs or mbuf clusters.
When this occurs, things can grind to a halt fairly quickly. However,
we currently do not call mb_reclaim() unless the entire system is
experiencing a low-memory condition.
While it is best to try to prevent exhaustion of one of the mbuf zones,
it would also be useful to have a mechanism to attempt to recover from
these situations by freeing "expendable" mbufs.
This patch makes two changes:
a) The patch adds a generic API to the UMA zone allocator to set a
function that should be called when an allocation fails because the
zone limit has been reached. Because of the way this function can be
called, it really should do minimal work.
b) The patch uses this API to try to free mbufs when an allocation
fails from one of the mbuf zones because the zone limit has been
reached. The function schedules a callout to run mb_reclaim().
Differential Revision: https://reviews.freebsd.org/D3864
Reviewed by: gnn
Comments by: rrs, glebius
MFC after: 2 weeks
Sponsored by: Juniper Networks
Different revisions support different operations. Refer to Intel
External Design Specifications to figure out what your hardware
supports.
Sponsored by: EMC / Isilon Storage Division
o With new KPI consumers can request contiguous ranges of pages, and
unlike before, all pages will be kept busied on return, like it was
done before with the 'reqpage' only. Now the reqpage goes away. With
new interface it is easier to implement code protected from race
conditions.
Such arrayed requests for now should be preceeded by a call to
vm_pager_haspage() to make sure that request is possible. This
could be improved later, making vm_pager_haspage() obsolete.
Strenghtening the promises on the business of the array of pages
allows us to remove such hacks as swp_pager_free_nrpage() and
vm_pager_free_nonreq().
o New KPI accepts two integer pointers that may optionally point at
values for read ahead and read behind, that a pager may do, if it
can. These pages are completely owned by pager, and not controlled
by the caller.
This shifts the UFS-specific readahead logic from vm_fault.c, which
should be file system agnostic, into vnode_pager.c. It also removes
one VOP_BMAP() request per hard fault.
Discussed with: kib, alc, jeff, scottl
Sponsored by: Nginx, Inc.
Sponsored by: Netflix
LLDB is usable for userland core file and live debugging on amd64, and
for userland core file debugging on arm64. In general it works at least
as well on FreeBSD as our in-tree gdb version, so enable it by default
to allow for broader use and testing.
An LLDB tutorial is available at http://lldb.llvm.org/tutorial.html, and
a table mapping GDB commands to LLDB commands can be found at
http://lldb.llvm.org/lldb-gdb.html .
LLDB also has some level of support for FreeBSD on arm, mips, i386,
and powerpc, but is not yet ready to have them enabled by default.
Reviewed by: gnn
Relnotes: Yes
This is not wrong, but was unexpected. Using <empty>:H results in '.' which
then using the rest of the conversion was added in RELDIR. This was also
causing an empty _DP_DIRDEPS to resolve to SRCTOP for DIRDEPS.
Sponsored by: EMC / Isilon Storage Division
This logic is potentially included multiple times, so overwrite the temporary
variable rather than append to it.
Sponsored by: EMC / Isilon Storage Division
This is because LDADD+=-lFOO is not the same as LDADD+=-lprivateFOO which is
what the private libs in LIBADD are.
Sponsored by: EMC / Isilon Storage Division
system call information such as system call arguments. Initially this
will consist of pulling duplicated code out of truss and kdump though it
may prove useful for other utilities in the future.
This commit moves the shared utrace(2) record parser out of kdump into
the library and updates kdump and truss to use it. One difference from
the previous version is that the library version treats unknown events
that start with the "RTLD" signature as unknown events. This simplifies
the interface and allows the consumer to decide how to handle all
non-recognized events. Instead, this function only generates a string
description for known malloc() and RTLD records.
Reviewed by: bdrewery
Differential Revision: https://reviews.freebsd.org/D4537
In I/OAT, this is done through the INTRDELAY register. On supported
platforms, this register can coalesce interrupts in a set period to
avoid excessive interrupt load for small descriptor workflows. The
period is configurable anywhere from 1 microsecond to 16.38
milliseconds, in microsecond granularity.
Sponsored by: EMC / Isilon Storage Division
These use ld(1), effectively -nostdlib, and don't need any of these
normal dependencies.
kmod builds also define PROG so just checking for KMOD here seems to be
the easiest to handle it.
Sponsored by: EMC / Isilon Storage Division
RISC-V is a new ISA designed to support computer research and education, and
is now become a standard open architecture for industry implementations.
This is a minimal set of changes required to run 'make kernel-toolchain'
using external (GNU) toolchain.
The FreeBSD/RISC-V project home: https://wiki.freebsd.org/riscv.
Reviewed by: andrew, bdrewery, emaste, imp
Sponsored by: DARPA, AFRL
Sponsored by: HEIF5
Differential Revision: https://reviews.freebsd.org/D4445
mps(4) sends StartStopUnit to SATA direct-access devices during shutdown.
Document the tunables which control that behavior.
PR: 195033
Reviewed by: scottl
Approved by: jhb
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4456
The hardware supports descriptors with two non-contiguous pages. This
allows issuing one descriptor for an 8k copy from/to non-contiguous but
otherwise page-aligned memory.
Sponsored by: EMC / Isilon Storage Division
Older ccache don't work with an empty CCACHE_PATH value. They will error with:
ccache: FATAL: Could not find compiler "cc" in PATH
make: "/mnt/bdrewery/git/onefs/src/share/mk/bsd.compiler.mk" line 134: Unable to determine compiler type for /usr/local/bin/ccache cc. Consider setting COMPILER_TYPE.
Sponsored by: EMC / Isilon Storage Division
STAGE_OBJTOP and STAGE_HOST_OBJTOP.
These will always be overridden in sub-makes when building in-tree, but
are exported for the benefit of hooking in external builds, such as
ports.
Sponsored by: EMC / Isilon Storage Division
- Don't bother looking up REVISION/BRANCH/etc from release/, or the
CPUTYPE check, as these are not used for makeman and wastes time. The also
invokes auto.obj.mk after I reverted auto.obj.mk ignoring -V in r291312.
- Don't modify CC or PATH when WITH_CCACHE_BUILD or WITH_META_MODE is enabled
as it leads to bsd.compiler.mk errors.
Sponsored by: EMC / Isilon Storage Division
These helper functions can be used to read in or write a buffer from or to
an arbitrary process' address space. Without them, this can only be done
using proc_rwmem(), which requires the caller to fill out a uio. This is
onerous and results in code duplication; the new functions provide a simpler
interface which is sufficient for most existing callers of proc_rwmem().
This change also adds a manual page for proc_rwmem() and the new functions.
Reviewed by: jhb, kib
Differential Revision: https://reviews.freebsd.org/D4245
