apfs/linux-apfs
0
0
Fork 0
mirror of https://github.com/linux-apfs/linux-apfs.git synced 2026-05-01 15:00:59 -07:00
Code Issues Packages Projects Releases Wiki Activity

spinlock: lockbreak cleanup

Browse Source 
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>
This commit is contained in:
Nick Piggin
2008-01-30 13:31:20 +01:00
committed by Ingo Molnar
parent a95d67f87e
commit 95c354fe9f
19 changed files with 72 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/mips/Kconfig
+5
View File
@@ -694,6 +694,11 @@ source "arch/mips/vr41xx/Kconfig"
endmenu
config GENERIC_LOCKBREAK
bool
default y
depends on SMP && PREEMPT
config RWSEM_GENERIC_SPINLOCK
bool
default y