XXX: We still install rmd160.h and sha2.h in /usr/include/crypto, unlike
the other hash functions which get installed in /usr/include for compatibility.
inserted or removed. Refactor node insertion to not require rebalancing
all the time or a loop if it does. In rb_tree_swap_prune_and_rebalance,
don't call rb_tree_reparent_nodes, instead do the work ourselves (since
we will eventually undo half of the work of rb_tree_reparent_nodes).
functions to a separate rb_tree_ops structure. Make every int explicit
in being signed or unsigned. Use RBDEBUG to enable debug code. Move
rbt_count to RBSTATS. Use RBSMALL to not keep track of min/max.
macros, __BIT, __BITS, SHIFTIN, SHIFTOUT, and __arraycount() from
lib/libkern/libkern.h to sys/cdefs.h. Add a __-prefix to SHIFTIN
and SHIFTOUT, and add a manual page for the bit-twiddling macros,
bits(3).
Make the __BIT and __BITS macros "widthless," as best I can, by
changing their type to uintmax_t from uint32_t. XXX The manual
page lags this change by a bit.
Define __PRIxBIT and __PRIxBITS printf(3) format strings.
- struct timeval time is gone
time.tv_sec -> time_second
- struct timeval mono_time is gone
mono_time.tv_sec -> time_uptime
- access to time via
{get,}{micro,nano,bin}time()
get* versions are fast but less precise
- support NTP nanokernel implementation (NTP API 4)
- further reading:
Timecounter Paper: http://phk.freebsd.dk/pubs/timecounter.pdf
NTP Nanokernel: http://www.eecis.udel.edu/~mills/ntp/html/kern.html
These sources are ported from FreeBSD/ia64 code.
See individual source files for credits.
In addition, code from NetBSD/alpha NetBSD/sparc64,
NetBSD/i386 and NetBSD/amd64 were used as templates,
along with my own additions.
counting the number of elements in a static array, using the idiom,
sizeof(array)/sizeof(array[0]).
XXX This may move in the future, but this is a safe place to put
XXX it for use in the kernel.
FROMBCD()/TOBCD() macros into wrappers around it, resulting in both
smaller code footprint and elimination of possible issues due to
multiple evaluation of macro arguments.
Suggested by Simon Burge and Anders Gavare on tech-kern.
I had duplicated them. Improve the macros' names. Simplify their
implementation.
A brief description of each macro is below.
BIT(n): Return a bitmask with bit m set, where the least
significant bit is bit 0.
BITS(m, n): Return a bitmask with bits m through n, inclusive,
set. It does not matter whether m>n or m<=n.
The least significant bit is bit 0.
A "bitfield" is a span of consecutive bits defined by a
bitmask, where 1s select the bits in the bitfield. SHIFTIN,
SHIFTOUT, and SHIFTOUT_MASK help read and write bitfields
from device registers.
SHIFTIN(v, mask): Left-shift bits `v' into the bitfield
defined by `mask', and return them. No
side-effects.
SHIFTOUT(v, mask): Extract and return the bitfield selected
by `mask' from `v', right-shifting the
bits so that the rightmost selected bit
is at bit 0. No side-effects.
SHIFTOUT_MASK(mask): Right-shift the bits in `mask' so that
the rightmost non-zero bit is at bit
0. This is useful for finding the
greatest unsigned value that a bitfield
can hold. No side-effects. Note that
SHIFTOUT_MASK(m) = SHIFTOUT(m, m).
Examples:
/*
* Register definitions taken from the RFMD RF3000 manual.
*/
#define RF3000_GAINCTL 0x11 /* TX variable gain control */
#define RF3000_GAINCTL_TXVGC_MASK BITS(7, 2)
#define RF3000_GAINCTL_SCRAMBLER BIT(1)
/*
* Shift the transmit power into the transmit-power field of the
* gain-control register and write it to the baseband processor.
*/
atw_rf3000_write(sc, RF3000_GAINCTL,
SHIFTIN(txpower, RF3000_GAINCTL_TXVGC_MASK));
/*
* Register definitions taken from the ADMtek ADM8211 manual.
*
*/
#define ATW_RXSTAT_OWN BIT(31) /* 1: NIC may fill descriptor */
/* ... */
#define ATW_RXSTAT_DA1 BIT(17) /* DA bit 1, admin'd address */
#define ATW_RXSTAT_DA0 BIT(16) /* DA bit 0, group address */
#define ATW_RXSTAT_RXDR_MASK BITS(15,12) /* RX data rate */
#define ATW_RXSTAT_FL_MASK BITS(11,0) /* RX frame length, last
* descriptor only
*/
/* Extract the frame length from the Rx descriptor's
* status field.
*/
len = SHIFTOUT(rxstat, ATW_RXSTAT_FL_MASK);
XXX: ptrdiff_t is only ever defined in <stddef.h> and is defined
unconditionally, without the ifndef dance. Until we have an expert
opinion, abuse intptr_t for the 't' size check.
