Using perf to trace L1 dcache misses and dumping data addresses I found a few
variables taking a lot of misses. Since they are almost never written, they
should go into the __read_mostly section.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch provides an extended_cede_processor() helper function
which takes the cede latency hint as an argument. This hint is to be passed
on to the hypervisor to cede to the corresponding state on platforms
which support it.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Arun R Bharadwaj <arun@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Prior to the arch/ppc -> arch/powerpc transition, xmon had support for single
stepping on 4xx boards. The functionality was lost when arch/ppc was removed.
This patch restores single step support for 44x boards, and Book-E in general.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The xmon code relies on MSR_RI being non-zero to indicate that an exception
is recoverable. If it is not, it prints a warning message. However, the
PowerPC 4xx cores do not have an MSR_RI bit and this warning is produced for
every xmon event.
This introduces an unrecoverable_excp function to determine if an exception
is recoverable or not. This gets rid of the erroneous warnings on 4xx.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Make it possible to enable GCOV code coverage measurement on powerpc.
Lightly tested on 64-bit, seems to work as expected.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This contains all the bits that didn't fit in previous patches :-) This
includes the actual exception handlers assembly, the changes to the
kernel entry, other misc bits and wiring it all up in Kconfig.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add the option to build the code under arch/powerpc with -Werror.
The intention is to make it harder for people to inadvertantly introduce
warnings in the arch/powerpc code. It needs to be configurable so that
if a warning is introduced, people can easily work around it while it's
being fixed.
The option is a negative, ie. don't enable -Werror, so that it will be
turned on for allyes and allmodconfig builds.
The default is n, in the hope that developers will build with -Werror,
that will probably lead to some build breaks, I am prepared to be flamed.
It's not enabled for math-emu, which is a steaming pile of warnings.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Gets rid of this warning:
arch/powerpc/xmon/xmon.c: In function 'dump_log_buf':
arch/powerpc/xmon/xmon.c:2133: warning: unused variable 'i'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Hello All,
Quite a while back Michael Ellerman had posted a patch to add support to xmon to print the contents of the console log pointed to by __log_buf.
Here's the link to that patch - http://ozlabs.org/pipermail/linuxppc64-dev/2005-March/003657.html
I've ported the patch in the above link to 2.6.30-rc5 and have tested it.
Thanks & regards,
Vinay
Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Today the arch/powerpc/xmon/setjmp.S file contains only the
xmon_save_regs function. We want to use it for kdump purposes, so
let's move the file into arch/powerpc/kernel/ and give the function a
more generic name (ppc_save_regs).
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes sure we don't try to call find_bug or is_warning_bug when
CONFIG_BUG=n and CONFIG_XMON=y. Otherwise we get these errors:
arch/powerpc/xmon/xmon.c: In function ‘print_bug_trap’:
arch/powerpc/xmon/xmon.c:1364: error: implicit declaration of function ‘find_bug’
arch/powerpc/xmon/xmon.c:1364: warning: assignment makes pointer from integer without a cast
arch/powerpc/xmon/xmon.c:1367: error: implicit declaration of function ‘is_warning_bug’
arch/powerpc/xmon/xmon.c:1374: error: dereferencing pointer to incomplete type
make[2]: *** [arch/powerpc/xmon/xmon.o] Error 1
make[1]: *** [arch/powerpc/xmon] Error 2
make: *** [sub-make] Error 2
Signed-off-by: Paul Mackerras <paulus@samba.org>
According to the CBEA, the SPU dsisr is not updated for class 0
exceptions.
spu_stopped() is testing the dsisr that was passed to it from the class
0 exception handler, so we return a false positive here.
This patch cleans up the interrupt handler and erroneous tests in
spu_stopped. It also removes the fields from the csa since it is not
needed to process class 0 events.
Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
This is a little messier than I'd like because xmon.h only exists
on powerpc and we can't have a static inline and an extern declaration
visible at the same time.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
warning: Using plain integer as NULL pointer
warning: Using plain integer as NULL pointer
warning: symbol 'excprint' was not declared. Should it be static?
warning: symbol 'prregs' was not declared. Should it be static?
warning: symbol 'cacheflush' was not declared. Should it be static?
warning: symbol 'read_spr' was not declared. Should it be static?
warning: symbol 'write_spr' was not declared. Should it be static?
warning: symbol 'super_regs' was not declared. Should it be static?
warning: symbol 'mread' was not declared. Should it be static?
warning: symbol 'mwrite' was not declared. Should it be static?
warning: symbol 'byterev' was not declared. Should it be static?
warning: symbol 'memex' was not declared. Should it be static?
warning: symbol 'bsesc' was not declared. Should it be static?
warning: symbol 'dump' was not declared. Should it be static?
warning: symbol 'prdump' was not declared. Should it be static?
warning: symbol 'generic_inst_dump' was not declared. Should it be static?
warning: symbol 'ppc_inst_dump' was not declared. Should it be static?
warning: symbol 'memops' was not declared. Should it be static?
warning: symbol 'memdiffs' was not declared. Should it be static?
warning: symbol 'memlocate' was not declared. Should it be static?
warning: symbol 'memzcan' was not declared. Should it be static?
warning: symbol 'proccall' was not declared. Should it be static?
warning: symbol 'scannl' was not declared. Should it be static?
warning: symbol 'hexdigit' was not declared. Should it be static?
warning: symbol 'flush_input' was not declared. Should it be static?
warning: symbol 'inchar' was not declared. Should it be static?
warning: symbol 'take_input' was not declared. Should it be static?
warning: symbol 'xmon_init' was not declared. Should it be static?
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
SPU class 0 & 1 exceptions may occur in parallel, so we may end up
overwriting csa.dsisr.
This change adds dedicated fields for each class to the spu and the spu
context so that fault data is not overwritten.
Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
This moves various definitions used all over the place to parse stack
frames to ptrace.h so only one definition is needed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that we have the alpaca, the reg_save_ptr is no longer needed in the
paca. Eradicate all global uses of it and make it static in the iSeries
lpardata.c
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes the setjmp/longjmp code used by xmon, generically available
to other code. It also removes the requirement for debugger hooks to
be only called on 0x300 (data storage) exception.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently we hardwire the number of SLBs to 64, but PAPR says we
should use the ibm,slb-size property to obtain the number of SLB
entries. This uses this property instead of assuming 64. If no
property is found, we assume 64 entries as before.
This soft patches the SLB handler, so it shouldn't change performance
at all.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds a function to xmon to dump the content of the 44x processor
TLB with a little bit of decoding (but not much).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In some configuration, xmon help string is larger than xmon_printf
buffer. We need not to use printf. This patch adds xmon_puts and
change to use it to show help string.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Because xmon_write doesn't change the buffer, we should add 'const'
qualifier to the argument which points it.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Several kallsyms_lookup() pass dummy arguments but only need, say, module's
name. Make kallsyms_lookup() accept NULLs where possible.
Also, makes picture clearer about what interfaces are needed for all symbol
resolving business.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Whenever we enter xmon we get a WARN_ON out of the rtas code since it
thinks interrupts are still on:
Unable to handle kernel paging request for data at address 0x00000000
Faulting instruction address: 0xd000000000080008
cpu 0x3: Vector: 300 (Data Access) at [c0000000075dba00]
pc: d000000000080008: .doit+0x8/0x40 [oopser]
lr: c000000000077704: .sys_init_module+0x1664/0x1824
sp: c0000000075dbc80
msr: 9000000000009032
dar: 0
dsisr: 42000000
current = 0xc000000003fa64b0
paca = 0xc000000000694280
pid = 2260, comm = insmod
------------[ cut here ]------------
Badness at arch/powerpc/kernel/entry_64.S:651
Call Trace:
[C0000000075DAE70] [C00000000000EB64] .show_stack+0x68/0x1b0 (unreliable)
[C0000000075DAF10] [C000000000216254] .report_bug+0x94/0xe8
[C0000000075DAFA0] [C00000000047B140] __kprobes_text_start+0x178/0x584
[C0000000075DB040] [C0000000000044F4] program_check_common+0xf4/0x100
Signed-off-by: Paul Mackerras <paulus@samba.org>
My patch to add spu disassembly (af89fb8041)
removed a newline from the xmon help that it shouldn't have, put it back.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It doesn't make any sense to have a priority field in the physical spu
structure. Move it into the spu context instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Use ARRAY_SIZE macro already defined in linux/kernel.h
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes powerpc use the generic BUG machinery. The biggest reports the
function name, since it is redundant with kallsyms, and not needed in general.
There is an overall reduction of code, since module_32/64 duplicated several
functions.
Unfortunately there's no way to tell gcc that BUG won't return, so the BUG
macro includes a goto loop. This will generate a real jmp instruction, which
is never used.
[akpm@osdl.org: build fix]
[paulus@samba.org: remove infinite loop in BUG_ON]
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
xmon still does not run on iSeries, but this allows us to build a combined
kernel that includes it.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It may be desireable to build a kernel for cell without
spufs, e.g. as the initial kboot kernel. This requires
that the SPU specific parts of the core dump and the xmon
code depend on CONFIG_SPU_BASE instead of CONFIG_PPC_CELL.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This fixes the xmon support for the cell spu to be compatable with the split
spu platform code.
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This includes:
* version 1.24 of ppc-dis.c
* version 1.88 of ppc-opc.c
* version 1.23 of ppc.h
I can't vouch for the accuracy etc. of these changes, but it brings
us into line with binutils - and from a cursory test appears to work
fine.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
While adding spu disassembly support it struck me that we're actually
carrying quite a lot of code around, just to do disassembly in the case
of a crash.
While on large systems it's not an issue, on smaller ones it might be
nice to have xmon - but without the weight of the disassembly support.
For a Cell build this saves ~230KB (!), and for pSeries ~195KB.
We still support the 'di' and 'sdi' commands, however they just dump
the instruction in hex.
Move the definitions into a header to clean xmon.c just a tiny bit.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch adds a "sdi" command to xmon, to disassemble the contents
of an spu's local store.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch imports and munges the spu disassembly code from binutils.
All files originated from version 1.1 in binutils cvs.
* spu.h, spu-insns.h and spu-opc.c are unchanged except for pathnames.
* spu-dis.c has been edited heavily:
* use printf instead of info->fprintf_func and similar.
* pass the instruction in rather than reading it.
* we have no equivalent to symbol_at_address_func, so we just assume
there is never a symbol at the address given.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
In order to do disassembly of spu binaries in xmon, we need to abstract
the disassembly function from ppc_inst_dump.
We do this by making the actual disassembly function a function pointer
that we pass to ppc_inst_dump(). To save updating all the callers, we
turn ppc_inst_dump() into generic_inst_dump() and make ppc_inst_dump()
a wrapper which always uses print_insn_powerpc().
Currently we pass the dialect into print_insn_powerpc(), but we always
pass 0 - so just make it a local.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Add a command to xmon to dump the memory of a spu's local store.
This mimics the 'd' command which dumps regular memory, but does
a little hand holding by taking the user supplied address and
finding that offset in the local store for the specified spu.
This makes it easy for example to look at what was executing on a spu:
1:mon> ss
...
Stopped spu 04 (was running)
...
1:mon> sf 4
Dumping spu fields at address c0000000019e0a00:
...
problem->spu_npc_RW = 0x228
...
1:mon> sd 4 0x228
d000080080318228 01a00c021cffc408 4020007f217ff488 |........@ ..!...|
Aha, 01a00c02, which is of course rdch $2,$ch24 !
--
Updated to only do the setjmp goo around the spu access, and not
around prdump because it does its own (via mread).
Also the num variable is now common between sf and sd, so you don't
have to keep typing the spu number in if you're repeating commands
on the same spu.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
After stopping spus in xmon I often find myself trawling through the
field dumps to find out which spus were running. The spu stopping
code actually knows what's running, so let's print it out to save
the user some futzing.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
My patch to add spu helpers to xmon (a898497088)
introduced a few sparse warnings, because I was dereferencing an __iomem
pointer.
I think the best way to handle it is to actually use the appropriate in_beXX
functions. Need to rejigger the DUMP macro a little to accomodate that.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch adds a command to xmon for dumping information about
spu structs. The command is 'sf' for "spu fields" perhaps, and
takes the spu number as an argument. This is the same value as the
spu->number field, or the "phys-id" value of a context when it is
bound to a physical spu.
We try to catch memory errors as we dump each field, hopefully this
will make the command reasonably robust, but YMMV. If people see a
need we can easily add more fields to the dump in future.
Output looks something like this:
0:mon> sf 0
Dumping spu fields at address c00000001ffd9e80:
number = 0x0
name = spe
devnode->full_name = /cpus/PowerPC,BE@0/spes/spe@0
nid = 0x0
local_store_phys = 0x20000000000
local_store = 0xd0000800801e0000
ls_size = 0x0
isrc = 0x4
node = 0x0
flags = 0x0
dar = 0x0
dsisr = 0x0
class_0_pending = 0
irqs[0] = 0x16
irqs[1] = 0x17
irqs[2] = 0x24
slb_replace = 0x0
pid = 0
prio = 0
mm = 0x0000000000000000
ctx = 0x0000000000000000
rq = 0x0000000000000000
timestamp = 0x0000000000000000
problem_phys = 0x20000040000
problem = 0xd000080080220000
problem->spu_runcntl_RW = 0x0
problem->spu_status_R = 0x0
problem->spu_npc_RW = 0x0
priv1 = 0xd000080080240000
priv1->mfc_sr1_RW = 0x33
priv2 = 0xd000080080250000
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds support for stopping, and restarting, spus
from xmon. We use the spu master runcntl bit to stop execution,
this is apparently the "right" way to control spu execution and
spufs will be changed in the future to use this bit.
Testing has shown that to restart execution we have to turn the
master runcntl bit on and also rewrite the spu runcntl bit, even
if it is already set to 1 (running).
Stopping spus is triggered by the xmon command 'ss' - "spus stop"
perhaps. Restarting them is triggered via 'sr'. Restart doesn't
start execution on spus unless they were running prior to being
stopped by xmon.
Walking the spu->full_list in xmon after a panic, would mean
corruption of any spu struct would make all the others
inaccessible. To avoid this, and also to make the next patch
easier, we cache pointers to all spus during boot.
We attempt to catch and recover from errors while stopping and
restarting the spus, but as with most xmon functionality there are
no guarantees that performing these operations won't crash xmon
itself.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Currently, if xmon has no input device (as is generally the case on
G5 powermacs), and we drop into xmon as a result of a fatal exception,
it will return 1, which die() interprets as "continue without causing
an oops". This fixes it by making xmon() return 0 in the case where
it has no input device.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Anton Blanchard