Some of the 64bit PPC CPU features are MMU-related, so this patch moves
them to MMU_FTR_ bits. All cpu_has_feature()-style tests are moved to
mmu_has_feature(), and seven feature bits are freed as a result.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Spinlocks on shared processor partitions use H_YIELD to notify the
hypervisor we are waiting on another virtual CPU. Unfortunately this means
the hcall tracepoints can recurse.
The patch below adds a percpu depth and checks it on both the entry and
exit hcall tracepoints.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@kernel.org
This introduces a pair of kernel parameters that can be used to disable
the MULTITCE and BULK_REMOVE h-calls.
By default, those hcalls are enabled, active, and good for throughput
and performance. The ability to disable them will be useful for some of
the PREEMPT_RT related investigation and work occurring on Power.
Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
cc: Olof Johansson <olof@lixom.net>
cc: Anton Blanchard <anton@samba.org>
cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently, when CONFIG_VIRT_CPU_ACCOUNTING is enabled, we use the
PURR register for measuring the user and system time used by
processes, as well as other related times such as hardirq and
softirq times. This turns out to be quite confusing for users
because it means that a program will often be measured as taking
less time when run on a multi-threaded processor (SMT2 or SMT4 mode)
than it does when run on a single-threaded processor (ST mode), even
though the program takes longer to finish. The discrepancy is
accounted for as stolen time, which is also confusing, particularly
when there are no other partitions running.
This changes the accounting to use the timebase instead, meaning that
the reported user and system times are the actual number of real-time
seconds that the program was executing on the processor thread,
regardless of which SMT mode the processor is in. Thus a program will
generally show greater user and system times when run on a
multi-threaded processor than on a single-threaded processor.
On pSeries systems on POWER5 or later processors, we measure the
stolen time (time when this partition wasn't running) using the
hypervisor dispatch trace log. We check for new entries in the
log on every entry from user mode and on every transition from
kernel process context to soft or hard IRQ context (i.e. when
account_system_vtime() gets called). So that we can correctly
distinguish time stolen from user time and time stolen from system
time, without having to check the log on every exit to user mode,
we store separate timestamps for exit to user mode and entry from
user mode.
On systems that have a SPURR (POWER6 and POWER7), we read the SPURR
in account_system_vtime() (as before), and then apportion the SPURR
ticks since the last time we read it between scaled user time and
scaled system time according to the relative proportions of user
time and system time over the same interval. This avoids having to
read the SPURR on every kernel entry and exit. On systems that have
PURR but not SPURR (i.e., POWER5), we do the same using the PURR
rather than the SPURR.
This disables the DTL user interface in /sys/debug/kernel/powerpc/dtl
for now since it conflicts with the use of the dispatch trace log
by the time accounting code.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently we have the lppaca structs as a simple array of NR_CPUS
entries, taking up space in the data section of the kernel image.
In future we would like to allocate them dynamically, so this
abstracts out the accesses to the array, making it easier to
change how we locate the lppaca for a given cpu in future.
Specifically, lppaca[cpu] changes to lppaca_of(cpu).
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently for kexec the PTE tear down on 1TB segment systems normally
requires 3 hcalls for each PTE removal. On a machine with 32GB of
memory it can take around a minute to remove all the PTEs.
This optimises the path so that we only remove PTEs that are valid.
It also uses the read 4 PTEs at once HCALL. For the common case where
a PTEs is invalid in a 1TB segment, this turns the 3 HCALLs per PTE
down to 1 HCALL per 4 PTEs.
This gives an > 10x speedup in kexec times on PHYP, taking a 32GB
machine from around 1 minute down to a few seconds.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
While most users of the hcall tracepoints will only want the opcode
and return code, some will want all the arguments. To avoid the
complexity of using varargs we pass a pointer to the register save
area, which contains all the arguments.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add hcall_entry and hcall_exit tracepoints. This replaces the inline
assembly HCALL_STATS code and converts it to use the new tracepoints.
To keep the disabled case as quick as possible, we embed a status word
in the TOC so we can get at it with a single load. By doing so we
keep the overhead at a minimum. Time taken for a null hcall:
No tracepoint code: 135.79 cycles
Disabled tracepoints: 137.95 cycles
For reference, before this patch enabling HCALL_STATS resulted in a null
hcall of 201.44 cycles!
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
In particular, pSeries_lpar_hpte_insert() goes from 185 instructions
to 77 instructions as a result of this patch. Luckily that code
isn't called very often ...
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
7284 1552 296 9132 23ac platforms/pseries/lpar.o
size after:
text data bss dec hex filename
5806 1096 296 7198 1c1e platforms/pseries/lpar.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Adds support for the "unused" page hint which can be used in shared
memory partitions to flag pages not in use, which will then be stolen
before active pages by the hypervisor when memory needs to be moved to
LPARs in need of additional memory. Failure to mark pages as 'unused'
makes the LPAR slower to give up unused memory to other partitions.
This adds the kernel parameter 'cmo_free_hint' to disable this
functionality.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It is okay for both _PAGE_GUARDED and _PAGE_COHERENT (G and M) to be set
in the same pte. In fact, even if that were not the case, there doesn't
seem to be any place where G is set without also setting I (_PAGE_NO_CACHE),
so the test for I is sufficient as a condition to clear _PAGE_COHERENT
when filling the hash table.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current low level hash code on LPAR configurations clears
_PAGE_COHERENT (M) when either _PAGE_GUARDED (G) or _PAGE_NO_CACHE (I)
is set. This conflicts with _PAGE_SAO which has M, I and W bits sets at
once (normally invalid combo) to indicate the new SAO attribute.
This changes the code to allow that case.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Don't return void in pseries/iommu.c
Make mce_data_buf static in pseries/ras.c
Make things static in pseries/rtasd.c
Make things static in pseries/setup.c
vtermno may as well be static in platforms/pseries/lpar.c
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In pseries/lpar.c, fix some printf specifier mismatches, and add
a newline to one printk.
In pseries/rtasd.c add "rtasd" to some messages to make it clear
where they're coming from.
In pseries/scanlog.c remove the hand-rolled runtime debugging support
in there. This file has been largely unchanged for eons, if we need to
debug it in future we can recompile.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On pseries LPAR we can call the udbg routines, and the udbg console very
early. So mark the udbg console as safe to call early in boot, and register
the udbg console as soon as the udbg routines are hooked up.
This allows platforms/pseries code to use printk() and pr_debug() rather
than needing to call udbg_printf() directly for early debugging. This is
nice because a) it's standard, b) it goes via the printk buffer, and c)
you can get printk time stamps.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There is logic in platforms/peries/lpars.c which checks if the user has
specified a console on the command line, and refrains from adding a
preferred console entry for the hvc/hvsi console if they have.
This trips up if you use "netconsole=foo" on the command line, and has
the result that you get _only_ the netconsole, because the hvc device is
never added as a preferred console. Worse still if you get the netconsole
configuration wrong somehow, you end up with no console at all.
As it turns out we don't need to worry about checking the command line.
If the user has specified "console=foo", then foo will be set as the
preferred console when the command line is parsed in start_kernel(), much
later than the pseries code, and so the latter setting will take effect.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Move the prototype for find_udbg_vterm() into pseries.h, removing
it from setup.c.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
For memory remove, we need to clean up htab mappings for the
section of the memory we are removing.
This implements support for removing htab bolted mappings for pSeries
logical partitions. Other sub-archs may need to implement similar
functionality for hotplug memory remove to work on them.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 473980a993 added a call to clear
the SLB shadow buffer before registering it. Unfortunately this means
that we clear out the entries that slb_initialize has previously set in
there. On POWER6, the hypervisor uses the SLB shadow buffer when doing
partition switches, and that means that after the next partition switch,
each non-boot CPU has no SLB entries to map the kernel text and data,
which causes it to crash.
This fixes it by reverting most of 473980a9 and instead clearing the
3rd entry explicitly in slb_initialize. This fixes the problem that
473980a9 was trying to solve, but without breaking POWER6.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Before we register the SLB shadow buffer, we need to invalidate the
entries in the buffer, otherwise we can end up stale entries from when
we previously offlined the CPU.
This does this invalidate as well as unregistering the buffer with
PHYP before we offline the cpu. Tested and fixes crashes seen on
970MP (thanks to tonyb) and POWER5.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes the kernel use 1TB segments for all kernel mappings and for
user addresses of 1TB and above, on machines which support them
(currently POWER5+, POWER6 and PA6T).
We detect that the machine supports 1TB segments by looking at the
ibm,processor-segment-sizes property in the device tree.
We don't currently use 1TB segments for user addresses < 1T, since
that would effectively prevent 32-bit processes from using huge pages
unless we also had a way to revert to using 256MB segments. That
would be possible but would involve extra complications (such as
keeping track of which segment size was used when HPTEs were inserted)
and is not addressed here.
Parts of this patch were originally written by Ben Herrenschmidt.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This removes several duplicate includes from arch/powerpc/.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On Power machines supporting VRMA, Kexec/Kdump does not work.
VRMA (virtual real-mode area) means that accesses with IR/DR = 0
(i.e. the MMU "off") actually still go through the hash table,
using entries put there by the hypervisor.
This means that when we clear out the hash table on kexec, we need to
make sure these entries are left untouched.
This also adds plpar_pte_read_raw() on the lines of
plpar_pte_remove_raw().
Signed-off-by : Sachin Sant <sachinp@in.ibm.com>
Signed-off-by : Mohan Kumar M <mohan@in.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
for consistency with other Open Firmware interfaces (and Sparc).
This is just a straight replacement.
This leaves the compatibility define in place.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
kexec invokes plpar_hcall hypervisor call in real mode. plpar_hcall
refers to per cpu variables for accounting hypervisor statistics.
These variables may not be in the RMO region, so accesses to them
in real mode may result in a data storage exception.
This fixes this problem by using a new plpar_hcall_raw function which
does not update the hypervisor call statistics. Thanks to Anton for
suggesting this idea.
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The previous patch changing pSeries to use H_BULK_REMOVE broke the
JS20 blade, where the firmware doesn't support H_BULK_REMOVE. This
adds a firmware check so that on machines that don't have H_BULK_REMOVE,
we just use the H_REMOVE call as before.
Signed-off-by: Paul Mackerras <paulus@samba.org>
H_BULK_REMOVE lets us remove 4 entries from the MMU hash table with one
hypervisor call. This uses it in pSeries_lpar_hpte_invalidate so we
can tear down mappings with fewer hypervisor calls.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Change the powerpc hpte_insert routines now called through ppc_md to
static scope.
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds a shadow buffer for the SLBs and regsiters it with PHYP.
Only the bolted SLB entries (top 3) are shadowed.
The SLB shadow buffer tells the hypervisor what the kernel needs to
have in the SLB for the kernel to be able to function. The hypervisor
can use this information to speed up partition context switches.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Our pseries hcall interfaces are out of control:
plpar_hcall_norets
plpar_hcall
plpar_hcall_8arg_2ret
plpar_hcall_4out
plpar_hcall_7arg_7ret
plpar_hcall_9arg_9ret
Create 3 interfaces to cover all cases:
plpar_hcall_norets: 7 arguments no returns
plpar_hcall: 6 arguments 4 returns
plpar_hcall9: 9 arguments 9 returns
There are only 2 cases in the kernel that need plpar_hcall9, hopefully
we can keep it that way.
Pass in a buffer to stash return parameters so we avoid the &dummy1,
&dummy2 madness.
Signed-off-by: Anton Blanchard <anton@samba.org>
--
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that get_property() returns a void *, there's no need to cast its
return value. Also, treat the return value as const, so we can
constify get_property later.
pseries platform changes.
Built for pseries_defconfig
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Initialise the ppc_md htab callbacks earlier, in the probe routines. This
allows us to call htab_finish_init() from htab_initialize(), and makes it
private to hash_utils_64.c. Move htab_finish_init() and make_bl() above
htab_initialize() to avoid forward declarations.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This extends the HCALL interface for InfiniBand usage. I've
made the patch against the linux-2.6 git tree and Segher's patch:
[PATCH] Change H_StudlyCaps to H_SHOUTING_CAPS
We moved this into the common powerpc code based on comments we
got after posting the first eHCA InfiniBand device driver patch.
Signed-off-by: Heiko j Schick <schickhj@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Also cleans up some nearby whitespace problems.
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At present the lppaca - the structure shared with the iSeries
hypervisor and phyp - is contained within the PACA, our own low-level
per-cpu structure. This doesn't have to be so, the patch below
removes it, making a separate array of lppaca structures.
This saves approximately 500*NR_CPUS bytes of image size and kernel
memory, because we don't need aligning gap between the Linux and
hypervisor portions of every PACA. On the other hand it means an
extra level of dereference in many accesses to the lppaca.
The patch also gets rid of several places where we assign the paca
address to a local variable for no particular reason.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The udbg low level io layer has an issue with udbg_getc() returning a
char (unsigned on ppc) instead of an int, thus the -1 if you had no
available input device could end up turned into 0xff, filling your
display with bogus characters. This fixes it, along with adding a little
blob to xmon to do a delay before exiting when getting an EOF and fixing
the detection of ADB keyboards in udbg_adb.c
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch unifies udbg for both ppc32 and ppc64 when building the
merged achitecture. xmon now has a single "back end". The powermac udbg
stuff gets enriched with some ADB capabilities and btext output. In
addition, the early_init callback is now called on ppc32 as well,
approx. in the same order as ppc64 regarding device-tree manipulations.
The init sequences of ppc32 and ppc64 are getting closer, I'll unify
them in a later patch.
For now, you can force udbg to the scc using "sccdbg" or to btext using
"btextdbg" on powermacs. I'll implement a cleaner way of forcing udbg
output to something else than the autodetected OF output device in a
later patch.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This moves the discovery of legacy serial ports to a separate file,
makes it common to ppc32 and ppc64, and reworks it to use the new OF
address translators to get to the ports early. This new version can also
detect some PCI serial cards using legacy chips and will probably match
those discovered port with the default console choice.
Only ppc64 gets udbg still yet, unifying udbg isn't finished yet.
It also adds some speed-probing code to udbg so that the default console
can come up at the same speed it was set to by the firmware.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Some debug code wasn't properly removed from the initial 64k pages
patch, and while it's harmless, it's also slowing down significantly a
very hot code path, thus it should really be removed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Mostly this involves adding #include <asm/smp.h>, since that defines
things like boot_cpuid[_phys] and [gs]et_hard_smp_processor_id, which
are SMP-related but still needed on UP. This incorporates fixes
posted by Olof Johansson and Heikki Lindholm.
Signed-off-by: Paul Mackerras <paulus@samba.org>
The ancient ppcdebug/PPCDBG mechanism is now only used in two places.
First, in the hash setup code, one of the bits allows the size of the
hash table to be reduced by a factor of 8 - which would be better
accomplished with a command line option for that purpose. The other
was a bunch of bus walking related messages in the iSeries code, which
would seem to be insufficient reason to keep the mechanism.
This patch removes the last traces of this mechanism.
Built and booted on iSeries and pSeries POWER5 LPAR (ARCH=powerpc).
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K. The resulting kernel still boots on any
hardware. On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.
Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
register_vpa() doesn't actually do a VPA register call it just uses the flags
you pass it, so rename it to vpa_call() to be clearer.
We can then define register_vpa() and unregister_vpa() which are both simple
wrappers around vpa_call(). (we'll need unregister_vpa() for kexec soon)
We can then cleanup vpa_init(), and because vpa_init() is only called from
platforms/pseries we remove the definition in asm-ppc64/smp.h.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Move plpar_wrappers.h into arch/powerpc/platforms/pseries, fixup white space,
and update callers.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
