MIPS: Crazy spinlock speed test.
This is just a test program for raw_spinlocks. The main reason I
wrote it is to validate my spinlock changes that I sent in a previous
patch.
To use it enable CONFIG_DEBUG_FS and CONFIG_SPINLOCK_TEST then at run
time do:
# mount -t debugfs none /sys/kernel/debug/
# cat /sys/kernel/debug/mips/spin_single
# cat /sys/kernel/debug/mips/spin_multi
On my 600MHz octeon cn5860 (16 CPUs) I get
spin_single spin_multi
base 106885 247941
spinlock_patch 75194 219465
This shows that for uncontended locks the spinlock patch gives 41%
improvement and for contended locks 12% improvement (1/time).
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/969/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Kconfig.debug b/arch/mips/Kconfig.debug
index 32a010d..43dc279 100644
--- a/arch/mips/Kconfig.debug
+++ b/arch/mips/Kconfig.debug
@@ -121,4 +121,11 @@
to reduce the kernel image size and speed up the booting procedure a
little.
+config SPINLOCK_TEST
+ bool "Enable spinlock timing tests in debugfs"
+ depends on DEBUG_FS
+ default n
+ help
+ Add several files to the debugfs to test spinlock speed.
+
endmenu