]> git.baikalelectronics.ru Git - kernel.git/commit
spinlock: lockbreak cleanup
authorNick Piggin <npiggin@suse.de>
Wed, 30 Jan 2008 12:31:20 +0000 (13:31 +0100)
committerIngo Molnar <mingo@elte.hu>
Wed, 30 Jan 2008 12:31:20 +0000 (13:31 +0100)
commit9a813a69339f692ee2c182631a0e77e1701692f5
treeec9267032ea875e84216cfb20acb2cfc7c62149f
parenteb196a165b341d256691d3513aa3dabf9ece1b14
spinlock: lockbreak cleanup

The break_lock data structure and code for spinlocks is quite nasty.
Not only does it double the size of a spinlock but it changes locking to
a potentially less optimal trylock.

Put all of that under CONFIG_GENERIC_LOCKBREAK, and introduce a
__raw_spin_is_contended that uses the lock data itself to determine whether
there are waiters on the lock, to be used if CONFIG_GENERIC_LOCKBREAK is
not set.

Rename need_lockbreak to spin_needbreak, make it use spin_is_contended to
decouple it from the spinlock implementation, and make it typesafe (rwlocks
do not have any need_lockbreak sites -- why do they even get bloated up
with that break_lock then?).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
19 files changed:
arch/arm/Kconfig
arch/ia64/Kconfig
arch/m32r/Kconfig
arch/mips/Kconfig
arch/parisc/Kconfig
arch/powerpc/Kconfig
arch/sparc64/Kconfig
arch/x86/Kconfig
fs/jbd/checkpoint.c
fs/jbd/commit.c
fs/jbd2/checkpoint.c
fs/jbd2/commit.c
include/linux/sched.h
include/linux/spinlock.h
include/linux/spinlock_types.h
include/linux/spinlock_up.h
kernel/sched.c
kernel/spinlock.c
mm/memory.c