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  1. 27 2月, 2010 1 次提交
    • D
      MIPS: Crazy spinlock speed test. · bba90760
      由 David Daney 提交于 
      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: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/969/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      bba90760
  3. 17 12月, 2009 5 次提交
    • R
      MIPS: Cleanup random differences beween lmo and Linus' kernel. · cf72e947
      由 Ralf Baechle 提交于 
      Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      cf72e947
    • W
      MIPS: Tracing: Add dynamic function tracer support · 538f1952
      由 Wu Zhangjin 提交于 
      With dynamic function tracer, by default, _mcount is defined as an
"empty" function, it returns directly without any more action . When
enabling it in user-space, it will jump to a real tracing
function(ftrace_caller), and do the real job for us.

Differ from the static function tracer, dynamic function tracer provides
two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the
tracing of some indicated kernel functions(set_ftrace_filter).

In the -v4 version, the implementation of this support is basically the same as
X86 version does: _mcount is implemented as an empty function and ftrace_caller
is implemented as a real tracing function respectively.

But in this version, to support module tracing with the help of
-mlong-calls in arch/mips/Makefile:

MODFLAGS += -mlong-calls.

The stuff becomes a little more complex. We need to cope with two
different type of calling to _mcount.

For the kernel part, the calling to _mcount(result of "objdump -hdr
vmlinux"). is like this:

	108:   03e0082d        move    at,ra
	10c:   0c000000        jal     0 <fpcsr_pending>
                        10c: R_MIPS_26  _mcount
                        10c: R_MIPS_NONE        *ABS*
                        10c: R_MIPS_NONE        *ABS*
	110:   00020021        nop

For the module with -mlong-calls, it looks like this:

	c:	3c030000 	lui	v1,0x0
			c: R_MIPS_HI16	_mcount
			c: R_MIPS_NONE	*ABS*
			c: R_MIPS_NONE	*ABS*
	10:	64630000 	daddiu	v1,v1,0
			10: R_MIPS_LO16	_mcount
			10: R_MIPS_NONE	*ABS*
			10: R_MIPS_NONE	*ABS*
	14:	03e0082d 	move	at,ra
	18:	0060f809 	jalr	v1

In the kernel version, there is only one "_mcount" string for every
kernel function, so, we just need to match this one in mcount_regex of
scripts/recordmcount.pl, but in the module version, we need to choose
one of the two to match. Herein, I choose the first one with
"R_MIPS_HI16 _mcount".

and In the kernel verion, without module tracing support, we just need
to replace "jal _mcount" by "jal ftrace_caller" to do real tracing, and
filter the tracing of some kernel functions via replacing it by a nop
instruction.

but as we have described before, the instruction "jal ftrace_caller" only left
32bit length for the address of ftrace_caller, it will fail when calling from
the module space. so, herein, we must replace something else.

the basic idea is loading the address of ftrace_caller to v1 via changing these
two instructions:

	lui	v1,0x0
	addiu	v1,v1,0

If we want to enable the tracing, we need to replace the above instructions to:

	lui	v1, HI_16BIT_ftrace_caller
	addiu	v1, v1, LOW_16BIT_ftrace_caller

If we want to stop the tracing of the indicated kernel functions, we
just need to replace the "jalr v1" to a nop instruction. but we need to
replace two instructions and encode the above two instructions
oursevles.

Is there a simpler solution? Yes! Here it is, in this version, we put _mcount
and ftrace_caller together, which means the address of _mcount and
ftrace_caller is the same:

_mcount:
ftrace_caller:
	j	ftrace_stub
	 nop

	...(do real tracing here)...

ftrace_stub:
	jr	ra
	 move	ra, at

By default, the kernel functions call _mcount, and then jump to ftrace_stub and
return. and when we want to do real tracing, we just need to remove that "j
ftrace_stub", and it will run through the two "nop" instructions and then do
the real tracing job.

what about filtering job? we just need to do this:

	 lui v1, hi_16bit_of_mcount        <--> b 1f (0x10000004)
	 addiu v1, v1, low_16bit_of_mcount
	 move at, ra
	 jalr v1
	 nop
	 				     1f: (rec->ip + 12)

In linux-mips64, there will be some local symbols, whose name are
prefixed by $L, which need to be filtered. thanks goes to Steven for
writing the mips64-specific function_regex.

In a conclusion, with RISC, things becomes easier with such a "stupid"
trick, RISC is something like K.I.S.S, and also, there are lots of
"simple" tricks in the whole ftrace support, thanks goes to Steven and
the other folks for providing such a wonderful tracing framework!
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/675/Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      538f1952
    • W
      MIPS: Tracing: Add static function tracer support for MIPS · d2bb0762
      由 Wu Zhangjin 提交于 
      If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to
_mcount will be inserted into each kernel function. so, there is a
possibility to trace the kernel functions in _mcount.

This patch add the MIPS specific _mcount support for static function
tracing. by default, ftrace_trace_function is initialized as
ftrace_stub(an empty function), so, the default _mcount will introduce
very little overhead. after enabling ftrace in user-space, it will jump
to a real tracing function and do static function tracing for us.

and -ffunction-sections is incompatible with -pg, so, disable it when
ftracer is enabled.
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Reviewed-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/672/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      d2bb0762
    • W
      MIPS: Loongson 2F: Add CPU frequency scaling support · f8ede0f7
      由 Wu Zhangjin 提交于 
      Loongson 2F supports CPU clock scaling. When put it into wait mode by
setting the frequency as ZERO it will stay in this mode until an external
interrupt wakes the CPU again.

To enable clock scaling support, an external timer of a known stable rate
is required.
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: cpufreq@vger.kernel.org,
Cc: Dave Jones <davej@redhat.com>,
Cc: Dominik Brodowski <linux@dominikbrodowski.net>,
Cc: yanh@lemote.com
Cc: huhb@lemote.com,
Patchwork: http://patchwork.linux-mips.org/patch/660/
Patchwork: http://patchwork.linux-mips.org/patch/751/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      f8ede0f7
    • D
      MIPS: PowerTV: Base files for Cisco PowerTV platform · a3a0f8c8
      由 David VomLehn 提交于 
      Add the Cisco Powertv cable settop box to the MIPS tree. This platform is
based on a MIPS 24Kc processor with various devices integrated on the same
ASIC. There are multiple models of this box, with differing configuration
but the same kernel runs across the product line.
Signed-off-by: NDavid VomLehn <dvomlehn@cisco.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/132/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      a3a0f8c8
  5. 26 9月, 2009 1 次提交
  7. 11 1月, 2009 2 次提交
  9. 28 10月, 2008 1 次提交
  11. 11 10月, 2008 1 次提交
  13. 04 10月, 2008 1 次提交
  15. 31 7月, 2008 2 次提交
  17. 16 7月, 2008 2 次提交
  19. 06 6月, 2008 1 次提交
  21. 12 5月, 2008 1 次提交
  23. 29 4月, 2008 5 次提交
  25. 17 4月, 2008 1 次提交
  27. 12 3月, 2008 1 次提交
  29. 27 11月, 2007 1 次提交
  31. 03 11月, 2007 1 次提交
  33. 30 10月, 2007 1 次提交
    • A
      [MIPS] txx9tmr clockevent/clocksource driver · 229f773e
      由 Atsushi Nemoto 提交于 
      Convert jmr3927_clock_event_device to more generic
txx9tmr_clock_event_device which supports one-shot mode.  The
txx9tmr_clock_event_device can be used for TX49 too if the cp0 timer
interrupt was not available.

Convert jmr3927_hpt_read to txx9_clocksource driver which does not
depends jiffies anymore.  The txx9_clocksource itself can be used for
TX49, but normally TX49 uses higher precision clocksource_mips.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      229f773e
  35. 23 10月, 2007 1 次提交
  37. 19 10月, 2007 1 次提交
  39. 15 10月, 2007 1 次提交
    • S
      kbuild: enable 'make CFLAGS=...' to add additional options to CC · a0f97e06
      由 Sam Ravnborg 提交于 
      The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.

This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.

One usecase is when trying to find gcc bugs but other
use cases has been requested too.

Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k

Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
      a0f97e06
  41. 12 10月, 2007 2 次提交
  43. 27 8月, 2007 1 次提交
  45. 01 8月, 2007 1 次提交
  47. 13 7月, 2007 1 次提交
  49. 11 7月, 2007 4 次提交