* offsetof is not allowed on non-POD types so we need to use
offset_of_member (gcc2 accepts offsetof, and C++11 relaxed the
constraints on where it is allowed so it should work there too)
* we have offset_of_member as a workaround until we switch to C++11,
move it from khash (which is soon to be removed) to list.h which is the
other place where it is used (for this one single call in our whole
codebase)
Also fix a typo in vfs.cpp.
* Instead of forcing the hash-table to use a copy of the key,
introduce and use TypeOperation template to avoid taking a
reference of a reference type (which gcc2 doesn't allow).
* The UNMAP command is theoretically much faster, as it can get many block
ranges instead of just a single range.
* Furthermore, the ATA TRIM command resembles it much better.
* Therefore, fs_trim_data now gets an array of ranges, and we use SCSI UNMAP
to trim.
* Updated BFS code to collect array ranges to fully support the new
fs_trim_data possibilities.
* No need for the atomically changed variables to be declared as
volatile.
* Drop support for atomically getting and setting unaligned data.
* Introduce atomic_get_and_set[64]() which works the same as
atomic_set[64]() used to. atomic_set[64]() does not return the
previous value anymore.
There is a global heap of cores, where the key is the highest priority
of threads running on that core. Moreover, for each core there is
a heap of logical processors on this core where the key is the priority
of currently running thread.
The per-core heap is used for load balancing among logical processors
on that core. The global heap is used in initial decision where to put
the thread (note that the algorithm that makes this decision is not
complete yet).
In SMP systems simple scheduler will be used only when all logical
processors share all levels of cache and the number of CPUs is low.
In such systems we do not have to care about cache affinity and
the contention on the lock protecting shared run queue is low. Single
run queue makes load balancing very simple.
Currently there are two generators. The fast one is the same one the scheduler
is using. The standard one is the same algorithm libroot's rand() uses. Should
there be a need for more cryptographically PRNG MD4 or MD5 might be a good
candidates.
* FixedWidthPointer:
- operators ==/!=: Change second operand type from void* to const
Type*. Also add non-const version to resolve ambiguity warning when
comparing with non-const pointer.
- Add Pointer() getter.
- Remove templatized cast operators. They are nice for casting the
pointer directly to another pointer type, but result in ambiguity.
* Make preloaded_image::debug_string_table non-const. Avoids clashes of
the const and non-coast FixedWidthPointer comparison operators. A
cleaner (but more verbose) solution would be to spezialize
FixedWidthPointer for const types.
