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A summary of 2.6.16 API changes
- The mutex code has been
merged. The use of semaphores for mutual exclusion is now deprecated,
and the current semaphore API may go away altogether.
- The high-resolution kernel
timer code has been merged. The new API allows for greater
precision in timer values, though the underlying implementation is
still limited by the timer interrupt resolution.
- A new list function, list_for_each_entry_safe_reverse(), does
just what one would expect.
- A 64-bit atomic type, atomic_long_t, has been added.
Supported functions are:
- long atomic_long_read(atomic_long_t *l);
- void atomic_long_set(atomic_long_t *l, long i);
- void atomic_long_inc(atomic_long_t *l);
- void atomic_long_dec(atomic_long_t *l);
- void atomic_long_add(long i, atomic_long_t *l);
- void atomic_long_sub(long i, atomic_long_t *l);
- The "SLOB" memory allocator has been merged. SLOB is a drop-in
replacement for the slab allocator, intended for very low-memory
systems.
- The dentry structure has been changed: the d_child
and d_rcu fields are now overlaid in a union. This change
shrinks this heavily-used structure and improves its cache behavior.
- The usb_driver structure has a new field
(no_dynamic_id) which lets a driver disable the addition of
dynamic device IDs. The owner field has also been removed
from this structure.
- The device probe() and remove() methods have been moved
from struct device_driver to struct bus_type. The
bus-level methods will override any remaining driver methods.
- Some significant changes to the SCSI subsystem aimed at eliminating
the use of the old scsi_request structure. The SCSI software
IRQ is no longer used; postprocessing happens via the generic block
software IRQ instead.
- Much of the core device model code has been reeducated to use the term
"uevent" instead of "hotplug." Some changes which are visible outside
of the core code include:
- kobject_hotplug() becomes kobject_uevent()
- struct kset_hotplug_ops becomes struct kset_uevent_ops, and its hotplug() member is now uevent()
- add_hotplug_env_var() becomes add_uevent_var()
- The block I/O barrier code has been rewritten. This
patch changes the barrier API and also adds a new parameter to
end_that_request_last().
- The block_device_operations structure has a new method
getgeo(); its job is to fill in an hd_geometry
structure with information about the drive. With this operation in
place, many block drivers will not need an ioctl() function
at all.
- Linas Vepstas's PCI error
recovery patch has been merged.
- Compilers prior to gcc 3.2 can no longer be used to build
kernels.
- The venerable "make bzImage" command no longer works; just type "make"
instead.
- When the kernel is configured to be optimized for size, gcc (if it's version 4.x) is given the freedom to decide whether inline functions should really be inlined. The __always_inline attribute now truly forces inlining in all cases. This is an outcome from the discussion on inline functions held at the beginning of the year.
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A summary of 2.6.16 API changes
Posted Mar 16, 2006 19:45 UTC (Thu) by ehovland (subscriber, #2284) [Link]
Perhaps you should pick either will or can.
There is a clock api in the kernel which changed between 2.6.15 and 2.6.16. It had a clk_use()/clk_unuse() set of functions to help with reference counting of clocks used. Both functions have disappeared and the refcounting has been put into the clk_enable()/clk_disable() calls. The header file for the clock system has moved from include/asm-*platform* to include/linux/clk.h.
Not sure if this change qualifies for your API doc. But I thought I would mention it.
bzImage target seems to be still here
Posted Mar 17, 2006 23:36 UTC (Fri) by kenmoffat (subscriber, #4807) [Link]
<quote> The venerable "make bzImage" command no longer works; just type "make" instead. </quote>
Umm, I'm just building a new linuxfromscratch system on x86 - I haven't conciously used 'make bzImage' for some time, but I thought I'd try it now (2.6.16-rc6) and there is no indication that it no longer works, first it told me
Kernel: arch/i386/boot/bzImage is ready (#1)
and sure enough, there it is.
I have no name! in chroot /usr/src/linux-2.6.16-rc6# ls -l arch/i386/boot/bzImage
-rw-r--r-- 1 root root 1766690 Mar 17 23:26 arch/i386/boot/bzImage
bzImage target seems to be still here
Posted Mar 24, 2006 15:08 UTC (Fri) by rvfh (subscriber, #31018) [Link]
...and that's fortunate, as 'make' makes both kernel and modules, which is not always what you want!