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bba9076058
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>
132 lines
4.6 KiB
Plaintext
132 lines
4.6 KiB
Plaintext
menu "Kernel hacking"
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config TRACE_IRQFLAGS_SUPPORT
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bool
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default y
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source "lib/Kconfig.debug"
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config EARLY_PRINTK
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bool "Early printk" if EMBEDDED
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depends on SYS_HAS_EARLY_PRINTK
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default y
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help
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This option enables special console drivers which allow the kernel
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to print messages very early in the bootup process.
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This is useful for kernel debugging when your machine crashes very
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early before the console code is initialized. For normal operation,
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it is not recommended because it looks ugly on some machines and
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doesn't cooperate with an X server. You should normally say N here,
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unless you want to debug such a crash.
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config CMDLINE_BOOL
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bool "Built-in kernel command line"
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default n
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help
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For most systems, it is firmware or second stage bootloader that
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by default specifies the kernel command line options. However,
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it might be necessary or advantageous to either override the
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default kernel command line or add a few extra options to it.
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For such cases, this option allows you to hardcode your own
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command line options directly into the kernel. For that, you
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should choose 'Y' here, and fill in the extra boot arguments
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in CONFIG_CMDLINE.
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The built-in options will be concatenated to the default command
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line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
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command line will be ignored and replaced by the built-in string.
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Most MIPS systems will normally expect 'N' here and rely upon
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the command line from the firmware or the second-stage bootloader.
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config CMDLINE
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string "Default kernel command string"
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depends on CMDLINE_BOOL
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default ""
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help
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On some platforms, there is currently no way for the boot loader to
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pass arguments to the kernel. For these platforms, and for the cases
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when you want to add some extra options to the command line or ignore
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the default command line, you can supply some command-line options at
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build time by entering them here. In other cases you can specify
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kernel args so that you don't have to set them up in board prom
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initialization routines.
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For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE
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options.
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config CMDLINE_OVERRIDE
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bool "Built-in command line overrides firware arguments"
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default n
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depends on CMDLINE_BOOL
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help
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By setting this option to 'Y' you will have your kernel ignore
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command line arguments from firmware or second stage bootloader.
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Instead, the built-in command line will be used exclusively.
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Normally, you will choose 'N' here.
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config DEBUG_STACK_USAGE
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bool "Enable stack utilization instrumentation"
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depends on DEBUG_KERNEL
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help
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Enables the display of the minimum amount of free stack which each
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task has ever had available in the sysrq-T and sysrq-P debug output.
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This option will slow down process creation somewhat.
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config SMTC_IDLE_HOOK_DEBUG
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bool "Enable additional debug checks before going into CPU idle loop"
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depends on DEBUG_KERNEL && MIPS_MT_SMTC
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help
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This option enables Enable additional debug checks before going into
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CPU idle loop. For details on these checks, see
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arch/mips/kernel/smtc.c. This debugging option result in significant
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overhead so should be disabled in production kernels.
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config SB1XXX_CORELIS
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bool "Corelis Debugger"
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depends on SIBYTE_SB1xxx_SOC
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select DEBUG_INFO
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help
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Select compile flags that produce code that can be processed by the
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Corelis mksym utility and UDB Emulator.
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config RUNTIME_DEBUG
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bool "Enable run-time debugging"
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depends on DEBUG_KERNEL
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help
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If you say Y here, some debugging macros will do run-time checking.
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If you say N here, those macros will mostly turn to no-ops. See
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arch/mips/include/asm/debug.h for debugging macros.
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If unsure, say N.
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config DEBUG_ZBOOT
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bool "Enable compressed kernel support debugging"
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depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT
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default n
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help
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If you want to add compressed kernel support to a new board, and the
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board supports uart16550 compatible serial port, please select
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SYS_SUPPORTS_ZBOOT_UART16550 for your board and enable this option to
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debug it.
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If your board doesn't support uart16550 compatible serial port, you
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can try to select SYS_SUPPORTS_ZBOOT and use the other methods to
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debug it. for example, add a new serial port support just as
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arch/mips/boot/compressed/uart-16550.c does.
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After the compressed kernel support works, please disable this option
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to reduce the kernel image size and speed up the booting procedure a
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little.
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config SPINLOCK_TEST
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bool "Enable spinlock timing tests in debugfs"
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depends on DEBUG_FS
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default n
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help
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Add several files to the debugfs to test spinlock speed.
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endmenu
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