Due to allocating tlb contexts on the fly, we only ever need to demap the
primary context, non-primary contexts have already been implicitly flushed
by context switching. All we really need to tell is if its a kernel demap
or not, and its easier just to compare against the kernel_pmap which is a
constant.
the context is not actually stolen, as it would be for i386. Instead of
deactivating a user vmspace immediately when switching out, and recycling
its tlb context, wait until the next context switch to a different user
vmspace. In this way we can switch from a user process to any number of
kernel threads and back to the same user process again, without losing any
of its mappings in the tlb that would not already be knocked by the automatic
replacement algorithm. This is not expected to have a measurable performance
improvement on the machines we currently run on, but it sounds cool and makes
the sparc64 port SMPng buzz word compliant.
to exhaust all kmaps. The only reward for setting maxproc
to a value which will cause kmap exhaustion is a panic
during a forkbomb attack.
MFC after: 3 days
generated the gmon data. The support is currently limited to what is
easy to implement and/or needed:
signedess: signed or insigned
size: 8, 16, 32 or 64 bits
format: a binary integer in gprof's format (gprof is not a cross-tool).
High-resolution kernel profiling uses signed 64-bit counters. Normal
kernel profiling and user profiling use unsigned 16-bit counters but
should use 32-bit ones.
Remove eaccess(2) absence workaround. Add eaccess(2) checks for FILRD,
FILWR, FILEX and FILEXIST cases.
We cannot MFC this because there is no eaccess(2) in -stable yet.
PR: bin/35076
Reviewed by: ru
Approved by: ru
things when sizeof(UNIT) becomes a runtime parameter. The relevant 2
is the one in profil(2)'s scaling of pc's to bucket numbers:
bucket = (pc - offset) / 2 * profil_scale / 65536
gprof(1) must duplicate this scaling, bug for bug compatibly, so it
must first do an integer division by 2 although this mainly makes
scales larger than 65536 useless. sizeof(UNIT) was already wrong in
gprof4, but there were no problems because the fake profil scale is a
multiple of 2.
There are also some rounding bugs in the scaling, but these are only
problems if profil(2) is used directly to create unusual (and not
useful) scales.
by removing parentheses. The main bug is in gcc: on machines with
64-bit longs and 64-bit long longs,
(unsigned long long)rdp->total_sectors / ((1024L * 1024L) / DEV_BSIZE))
has type plain unsigned long instead of the correctly promoted type
unsigned long long, so it can not be printfed using %llu format. Even
1ULL / 1L is mispromoted. Anyway, casting the correct operand
automatically avoids the problem. We do not want to to pessimize the
division; we just want to convert to a common maximal type for printing.
moderately improves msync's and VM object flushing for objects containing
randomly dirtied pages (fsync(), msync(), filesystem update daemon),
and improves cpu use for small-ranged sequential msync()s in the face of
very large mmap()ings from O(N) to O(1) as might be performed by a database.
A sysctl, vm.msync_flush_flag, has been added and defaults to 3 (the two
committed optimizations are turned on by default). 0 will turn off both
optimizations.
This code has already been tested under stable and is one in a series of
memq / vp->v_dirtyblkhd / fsync optimizations to remove O(N^2) restart
conditions that will be coming down the pipe.
MFC after: 3 days
applications linked with Linux-PAM will still work.
Remove pam_get_pass(); OpenPAM has pam_get_authtok().
Remove pam_prompt(); OpenPAM has pam_{,v}{error,info,prompt}().
Remove pam_set_item(3) man page as OpenPAM has its own.
Sponsored by: DARPA, NAI Labs
