Commit Graph

13168 Commits

Author SHA1 Message Date
Yinghai Lu
12031a624a x86: mtrr cleanup for converting continuous to discrete - auto detect v4
Loop through mtrr chunk_size and gran_size from 1M to 2G to find out
the optimal value so user does not need to add mtrr_chunk_size and
mtrr_gran_size to the kernel command line.

If optimal value is not found, print out all list to help select less
optimal value.

Add mtrr_spare_reg_nr= so user could set 2 instead of 1, if the card
need more entries.

v2: find the one with more spare entries
v3: fix hole_basek offset
v4: tight the compare between range and range_new
    loop stop with 4g

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Gabriel C <nix.or.die@googlemail.com>
Cc: Mika Fischer <mika.fischer@zoopnet.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 10:55:10 +02:00
Yinghai Lu
f5098d62c1 x86: mtrr cleanup for converting continuous to discrete layout v8 - fix
v9: address format change requests by Ingo
    more case handling in range_to_var_with_hole

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 10:55:10 +02:00
Yinghai Lu
8a374026c2 x86: fix trimming e820 with MTRR holes. - fix
v2: process hole then end_pfn
    fix update_memory_range with whole cover comparing

Signed-off-by: Yinghai Lu <yinghai.lu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 10:55:10 +02:00
Yinghai Lu
42651f1582 x86: fix trimming e820 with MTRR holes.
converting MTRR layout from continous to discrete, some time could run out of
MTRRs. So add gran_sizek to prevent that by dumpping small RAM piece less than
gran_sizek.

previous trimming only can handle highest_pfn from mtrr to end_pfn from e820.
when have more than 4g RAM installed, there will be holes below 4g. so need to
check ram below 4g is coverred well.

need to be applied after
	[PATCH] x86: mtrr cleanup for converting continuous to discrete layout v7

Signed-off-by: Yinghai Lu <yinghai.lu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 10:55:09 +02:00
Yinghai Lu
95ffa2438d x86: mtrr cleanup for converting continuous to discrete layout, v8
some BIOS like to use continus MTRR layout, and X driver can not add
WB entries for graphical cards when 4g or more RAM installed.

the patch will change MTRR to discrete.

mtrr_chunk_size= could be used to have smaller continuous block to hold holes.
default is 256m, could be set according to size of graphics card memory.

mtrr_gran_size= could be used to send smallest mtrr block to avoid run out of MTRRs

v2: fix -1 for UC checking
v3: default to disable, and need use enable_mtrr_cleanup to enable this feature
    skip the var state change warning.
    remove next_basek in range_to_mtrr()
v4: correct warning mask.
v5: CONFIG_MTRR_SANITIZER
v6: fix 1g, 2g, 512 aligment with extra hole
v7: gran_sizek to prevent running out of MTRRs.
v8: fix hole_basek caculation caused when removing next_basek
    gran_sizek using when basek is 0.

need to apply
	[PATCH] x86: fix trimming e820 with MTRR holes.
right after this one.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 10:55:09 +02:00
Alexander van Heukelum
0dbfafa5fc x86: move i386 memory setup code to e820_32.c
The x86_64 code has centralized the memory setup code in
e820_64.c. This patch copies that approach to i386:

- early_param("mem", ...) parsing is moved from
setup_32.c to e820_32.c.

- setup_memory_map() and finish_e820_parsing() are
factored out from setup_arch(), and declarations
are added to e820_32.h.

- print_memory_map() is made static and removed from
e820_32.h.

- user_defined_memmap is marked as __initdata.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 10:55:09 +02:00
Thomas Gleixner
0da72a4aeb x86: fix sparse warning in mtrr/generic.c
arch/x86/kernel/cpu/mtrr/generic.c:216:12: warning: symbol 'lo' shadows an earlier one

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 10:55:09 +02:00
Jan Beulich
83cd1daa1d x86: eliminate dead code in x86_64 entry.S
Remove the not longer used handlers for reserved vectors.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 08:58:36 +02:00
Miklos Vajna
bfe4bb1526 x86: janitor work in bugs.c
Just moved trailing statements to the next line, removed space before
open/close parenthesis, wrapped long lines.

Signed-off-by: Miklos Vajna <vmiklos@frugalware.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 08:58:34 +02:00
Cyrill Gorcunov
0e192b99d7 x86: head_64.S cleanup - use PMD_SHIFT instead of numeric constant
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:58:33 +02:00
Cyrill Gorcunov
05139d8fb4 x86: head_64.S cleanup - use straight move to CR4 register
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:58:33 +02:00
Huang Weiyi
883b7af932 x86: smpboot.c: removed duplicated include
Removed duplicated include <asm/nmi.h> in
arch/x86/kernel/smpboot.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 08:58:32 +02:00
Huang Weiyi
2cc74111c7 x86: ipi.c: removed duplicated include
Removed duplicated include <linux/interrupt.h> in
arch/x86/kernel/ipi.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 08:58:32 +02:00
Cyrill Gorcunov
369101da7e x86: head_64.S cleanup - use predefined flags from processor-flags.h
We should better use already defined flags from processor-flags.h instead
of defining own ones

[>>> object code check >>>]

original
md5sum: 9cfa6dbf045a046bb5dfb85f8bcfe8c4  arch/x86/kernel/head_64.o
   text    data     bss     dec     hex filename
  37361    4432    8192   49985    c341 arch/x86/kernel/head_64.o

patched
md5sum: 9cfa6dbf045a046bb5dfb85f8bcfe8c4  arch/x86/kernel/head_64.o
   text    data     bss     dec     hex filename
  37361    4432    8192   49985    c341 arch/x86/kernel/head_64.o

[<<< object code check <<<]

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:58:31 +02:00
Jan Beulich
ebdd561a19 x86: constify data in reboot.c
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 08:58:30 +02:00
Adrian Bunk
311f834948 x86: kernel/pci-dma.c cleanups
This patch contains the following cleanups:
- make the following needlessly global code static:
  - dma_alloc_pages()

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 08:58:28 +02:00
Thomas Gleixner
e0b32d768c x86: make command_line static in setup_64.c
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:58:27 +02:00
Thomas Gleixner
d1097635de x86: move mmconfig declarations to header
arch/x86/kernel/mmconf-fam10h_64.c is missing the prototypes, which
are decalred in arch/x86/kernel/setup_64.c. Move the prototypes and
the inline stubs to the appropriate header file.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:58:27 +02:00
Thomas Gleixner
eef8f871d8 x86: vsmp_64 add missing includes
sparse mutters:
arch/x86/kernel/vsmp_64.c:126:5: warning: symbol 'is_vsmp_box' was not declared. Should it be static?
arch/x86/kernel/vsmp_64.c:145:13: warning: symbol 'vsmp_init' was not declared. Should it be static?

Include the appropriate headers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:58:24 +02:00
Thomas Gleixner
c2c14fb7af x86: tsc_64.c make constant UL
arch/x86/kernel/tsc_64.c:245:13: warning: constant 0x100000000 is so big it is long

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-25 08:39:27 +02:00
Jan Beulich
a2eddfa959 x86: make /proc/stat account for all interrupts
LAPIC interrupts, which don't go through the generic interrupt handling
code, aren't accounted for in /proc/stat. Hence this patch adds a
mechanism architectures can use to accordingly adjust the statistics.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:11:49 +02:00
Jan Beulich
63687a528c x86: move tracedata to RODATA
.. allowing it to be write-protected just as other read-only data
under CONFIG_DEBUG_RODATA.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:09:47 +02:00
Jan Beulich
6360b1fbb4 move BUG_TABLE into RODATA
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:06:08 +02:00
Eric Dumazet
63cc8c7515 percpu: introduce DEFINE_PER_CPU_PAGE_ALIGNED() macro
While examining holes in percpu section I found this :

c05f5000 D per_cpu__current_task
c05f5000 D __per_cpu_start
c05f5004 D per_cpu__cpu_number
c05f5008 D per_cpu__irq_regs
c05f500c d per_cpu__cpu_devices
c05f5040 D per_cpu__cyc2ns

<Big Hole of about 4000 bytes>

c05f6000 d per_cpu__cpuid4_info
c05f6004 d per_cpu__cache_kobject
c05f6008 d per_cpu__index_kobject

<Big Hole of about 4000 bytes>

c05f7000 D per_cpu__gdt_page

This is because gdt_page is a percpu variable, defined with
a page alignement, and linker is doing its job, two times because of .o
nesting in the build process.

I introduced a new macro DEFINE_PER_CPU_PAGE_ALIGNED() to avoid
wasting this space. All page aligned variables (only one at this time)
are put in a separate
subsection .data.percpu.page_aligned, at the very begining of percpu zone.

Before patch , on a x86_32 machine :

.data.percpu                30232   3227471872
.data.percpu                22168   3227471872

Thats 8064 bytes saved for each CPU.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:03:46 +02:00
Linus Torvalds
eb90d81d03 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
  x86: prevent PGE flush from interruption/preemption
  x86: use explicit copy in vdso_gettimeofday()
  namespacecheck: automated fixes
  x86/xen: fix arbitrary_virt_to_machine()
  x86: don't read maxlvt before checking if APIC is mapped
  x86: disable TSC for sched_clock() when calibration failed
  x86: distangle user disabled TSC from unstable
  x86: fix setup of cyc2ns in tsc_64.c
2008-05-24 10:20:00 -07:00
Thomas Gleixner
ec42418f19 x86: rename the i8259_32/64.c leftovers to irqinit_32/64.c
The leftovers of the i8259 unification have nothing to do with i8259
at all. They contain interrupt init code and the i8259_xx name is just
misleading now.

Rename them to irqinit_32/64.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 16:47:39 +02:00
Thomas Gleixner
d23b200a75 x86: make init_ISA_irqs() static
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-24 16:45:36 +02:00
Pavel Machek
680afbf989 x86: i8259: cleanup codingstyle
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: macro@ds2.pg.gda.pl
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 16:44:26 +02:00
Pavel Machek
3e8631d270 x86: i8259.c: remove trivial ifdefs
Remove #ifdefs where the only difference is formatting of comments.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: macro@ds2.pg.gda.pl
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 16:44:26 +02:00
Pavel Machek
15d613cb25 x86: i8259.c: remove #ifdefs around includes
Remove #ifdefs around includes; including too much should be always
safe.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: macro@ds2.pg.gda.pl
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 16:44:26 +02:00
Pavel Machek
21fd5132b2 x86: automatical unification of i8259.c
Make conversion of i8259 very mechanical -- i8259 was generated by
 diff -D, with too different parts left in i8259_32 and
i8259_64.c. Only "by hand" changes were removal of #ifdef from middle
of the comment (prevented compilation) and removal of one static to
allow splitting into files.

Of course, it will need some cleanups now, and those will follow.

Signed-of-by: Pavel Machek <pavel@suse.cz>
2008-05-24 16:44:26 +02:00
Thomas Gleixner
fce39665ab x86: make init_ISA_irqs() static
Moved to i8259 branch to avoid conflicts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-24 16:21:47 +02:00
Thomas Gleixner
f20b11e716 x86: rename the i8259_32/64.c leftovers to initirq_32/64.c
The leftovers of the i8259 unification have nothing to do with i8259
at all. They contain interrupt init code and the i8259_xx name is just
misleading now.

Rename them to initirq_32/64.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 15:59:58 +02:00
Pavel Machek
4d9a6e6128 x86: i8259: cleanup codingstyle
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: macro@ds2.pg.gda.pl
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 15:57:10 +02:00
Pavel Machek
4f6f3bac18 x86: i8259.c: remove trivial ifdefs
Remove #ifdefs where the only difference is formatting of comments.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: macro@ds2.pg.gda.pl
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 15:57:10 +02:00
Pavel Machek
6b4d3afbe7 x86: i8259.c: remove #ifdefs around includes
Remove #ifdefs around includes; including too much should be always
safe.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: macro@ds2.pg.gda.pl
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-24 15:57:09 +02:00
Pavel Machek
40bd217400 x86: automatical unification of i8259.c
Make conversion of i8259 very mechanical -- i8259 was generated by
2008-05-24 15:57:09 +02:00
Steven Rostedt
7fa09f24b4 ftrace: use the new kbuild CFLAGS_REMOVE for x86/kernel directory
This patch removes the Makefile turd and uses the nice CFLAGS_REMOVE macro
in the x86/kernel directory.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 22:48:00 +02:00
Ingo Molnar
37135677e6 ftrace: fix mcount export bug
David S. Miller noticed the following bug: the -pg instrumentation
function callback is named differently on each platform. On x86 it
is mcount, on sparc it is _mcount. So the export does not make sense
in kernel/trace/ftrace.c - move it to x86.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 22:36:24 +02:00
Pekka Paalanen
2f1dafe50c x86: fix SMP alternatives: use mutex instead of spinlock, text_poke is sleepable
text_poke is sleepable.
The original fix by Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 21:56:52 +02:00
Steven Rostedt
a56be3fe2f ftrace: fix the fault label in updating code
The fault label to jump to on fault of updating the code was misplaced
preventing the fault from being recorded.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 21:16:12 +02:00
Ingo Molnar
f43fdad862 ftrace: fix kexec
disable the tracer while kexec pulls the rug from under the old
kernel.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:39:05 +02:00
Steven Rostedt
d61f82d066 ftrace: use dynamic patching for updating mcount calls
This patch replaces the indirect call to the mcount function
pointer with a direct call that will be patched by the
dynamic ftrace routines.

On boot up, the mcount function calls the ftace_stub function.
When the dynamic ftrace code is initialized, the ftrace_stub
is replaced with a call to the ftrace_record_ip, which records
the instruction pointers of the locations that call it.

Later, the ftraced daemon will call kstop_machine and patch all
the locations to nops.

When a ftrace is enabled, the original calls to mcount will now
be set top call ftrace_caller, which will do a direct call
to the registered ftrace function. This direct call is also patched
when the function that should be called is updated.

All patching is performed by a kstop_machine routine to prevent any
type of race conditions that is associated with modifying code
on the fly.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:33:47 +02:00
Steven Rostedt
3c1720f00b ftrace: move memory management out of arch code
This patch moves the memory management of the ftrace
records out of the arch code and into the generic code
making the arch code simpler.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:33:35 +02:00
Steven Rostedt
dfa60aba04 ftrace: use nops instead of jmp
This patch patches the call to mcount with nops instead
of a jmp over the mcount call.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:33:28 +02:00
Steven Rostedt
3d0833953e ftrace: dynamic enabling/disabling of function calls
This patch adds a feature to dynamically replace the ftrace code
with the jmps to allow a kernel with ftrace configured to run
as fast as it can without it configured.

The way this works, is on bootup (if ftrace is enabled), a ftrace
function is registered to record the instruction pointer of all
places that call the function.

Later, if there's still any code to patch, a kthread is awoken
(rate limited to at most once a second) that performs a stop_machine,
and replaces all the code that was called with a jmp over the call
to ftrace. It only replaces what was found the previous time. Typically
the system reaches equilibrium quickly after bootup and there's no code
patching needed at all.

e.g.

  call ftrace  /* 5 bytes */

is replaced with

  jmp 3f  /* jmp is 2 bytes and we jump 3 forward */
3:

When we want to enable ftrace for function tracing, the IP recording
is removed, and stop_machine is called again to replace all the locations
of that were recorded back to the call of ftrace.  When it is disabled,
we replace the code back to the jmp.

Allocation is done by the kthread. If the ftrace recording function is
called, and we don't have any record slots available, then we simply
skip that call. Once a second a new page (if needed) is allocated for
recording new ftrace function calls.  A large batch is allocated at
boot up to get most of the calls there.

Because we do this via stop_machine, we don't have to worry about another
CPU executing a ftrace call as we modify it. But we do need to worry
about NMI's so all functions that might be called via nmi must be
annotated with notrace_nmi. When this code is configured in, the NMI code
will not call notrace.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:33:09 +02:00
Steven Rostedt
6cd8a4bb2f ftrace: trace preempt off critical timings
Add preempt off timings. A lot of kernel core code is taken from the RT patch
latency trace that was written by Ingo Molnar.

This adds "preemptoff" and "preemptirqsoff" to /debugfs/tracing/available_tracers

Now instead of just tracing irqs off, preemption off can be selected
to be recorded.

When this is selected, it shares the same files as irqs off timings.
One can either trace preemption off, irqs off, or one or the other off.

By echoing "preemptoff" into /debugfs/tracing/current_tracer, recording
of preempt off only is performed. "irqsoff" will only record the time
irqs are disabled, but "preemptirqsoff" will take the total time irqs
or preemption are disabled. Runtime switching of these options is now
supported by simpling echoing in the appropriate trace name into
/debugfs/tracing/current_tracer.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:32:54 +02:00
Steven Rostedt
81d68a96a3 ftrace: trace irq disabled critical timings
This patch adds latency tracing for critical timings
(how long interrupts are disabled for).

 "irqsoff" is added to /debugfs/tracing/available_tracers

Note:
  tracing_max_latency
    also holds the max latency for irqsoff (in usecs).
   (default to large number so one must start latency tracing)

  tracing_thresh
    threshold (in usecs) to always print out if irqs off
    is detected to be longer than stated here.
    If irq_thresh is non-zero, then max_irq_latency
    is ignored.

Here's an example of a trace with ftrace_enabled = 0

=======
preemption latency trace v1.1.5 on 2.6.24-rc7
Signed-off-by: Ingo Molnar <mingo@elte.hu>
--------------------------------------------------------------------
 latency: 100 us, #3/3, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------
 => started at: _spin_lock_irqsave+0x2a/0xb7
 => ended at:   _spin_unlock_irqrestore+0x32/0x5f

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     1d.s3    0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
 swapper-0     1d.s3  100us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1d.s3  100us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)

vim:ft=help
=======

And this is a trace with ftrace_enabled == 1

=======
preemption latency trace v1.1.5 on 2.6.24-rc7
--------------------------------------------------------------------
 latency: 102 us, #12/12, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------
 => started at: _spin_lock_irqsave+0x2a/0xb7
 => ended at:   _spin_unlock_irqrestore+0x32/0x5f

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     1dNs3    0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
 swapper-0     1dNs3   46us : e1000_read_phy_reg+0x16/0x225 [e1000] (e1000_update_stats+0x5e2/0x64c [e1000])
 swapper-0     1dNs3   46us : e1000_swfw_sync_acquire+0x10/0x99 [e1000] (e1000_read_phy_reg+0x49/0x225 [e1000])
 swapper-0     1dNs3   46us : e1000_get_hw_eeprom_semaphore+0x12/0xa6 [e1000] (e1000_swfw_sync_acquire+0x36/0x99 [e1000])
 swapper-0     1dNs3   47us : __const_udelay+0x9/0x47 (e1000_read_phy_reg+0x116/0x225 [e1000])
 swapper-0     1dNs3   47us+: __delay+0x9/0x50 (__const_udelay+0x45/0x47)
 swapper-0     1dNs3   97us : preempt_schedule+0xc/0x84 (__delay+0x4e/0x50)
 swapper-0     1dNs3   98us : e1000_swfw_sync_release+0xc/0x55 [e1000] (e1000_read_phy_reg+0x211/0x225 [e1000])
 swapper-0     1dNs3   99us+: e1000_put_hw_eeprom_semaphore+0x9/0x35 [e1000] (e1000_swfw_sync_release+0x50/0x55 [e1000])
 swapper-0     1dNs3  101us : _spin_unlock_irqrestore+0xe/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1dNs3  102us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1dNs3  102us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)

vim:ft=help
=======

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:32:46 +02:00
Arnaldo Carvalho de Melo
16444a8a40 ftrace: add basic support for gcc profiler instrumentation
If CONFIG_FTRACE is selected and /proc/sys/kernel/ftrace_enabled is
set to a non-zero value the ftrace routine will be called everytime
we enter a kernel function that is not marked with the "notrace"
attribute.

The ftrace routine will then call a registered function if a function
happens to be registered.

[ This code has been highly hacked by Steven Rostedt and Ingo Molnar,
  so don't blame Arnaldo for all of this ;-) ]

Update:
  It is now possible to register more than one ftrace function.
  If only one ftrace function is registered, that will be the
  function that ftrace calls directly. If more than one function
  is registered, then ftrace will call a function that will loop
  through the functions to call.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:31:58 +02:00
Steven Rostedt
23adec554a x86: add notrace annotations to vsyscall.
Add the notrace annotations to the vsyscall functions - there we are
not in kernel context yet, so the tracer function cannot (and must not)
be called.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:31:39 +02:00