Here is the patch to implement madvise(MADV_REMOVE) - which frees up a
given range of pages & its associated backing store. Current
implementation supports only shmfs/tmpfs and other filesystems return
-ENOSYS.
"Some app allocates large tmpfs files, then when some task quits and some
client disconnect, some memory can be released. However the only way to
release tmpfs-swap is to MADV_REMOVE". - Andrea Arcangeli
Databases want to use this feature to drop a section of their bufferpool
(shared memory segments) - without writing back to disk/swap space.
This feature is also useful for supporting hot-plug memory on UML.
Concerns raised by Andrew Morton:
- "We have no plan for holepunching! If we _do_ have such a plan (or
might in the future) then what would the API look like? I think
sys_holepunch(fd, start, len), so we should start out with that."
- Using madvise is very weird, because people will ask "why do I need to
mmap my file before I can stick a hole in it?"
- None of the other madvise operations call into the filesystem in this
manner. A broad question is: is this capability an MM operation or a
filesytem operation? truncate, for example, is a filesystem operation
which sometimes has MM side-effects. madvise is an mm operation and with
this patch, it gains FS side-effects, only they're really, really
significant ones."
Comments:
- Andrea suggested the fs operation too but then it's more efficient to
have it as a mm operation with fs side effects, because they don't
immediatly know fd and physical offset of the range. It's possible to
fixup in userland and to use the fs operation but it's more expensive,
the vmas are already in the kernel and we can use them.
Short term plan & Future Direction:
- We seem to need this interface only for shmfs/tmpfs files in the short
term. We have to add hooks into the filesystem for correctness and
completeness. This is what this patch does.
- In the future, plan is to support both fs and mmap apis also. This
also involves (other) filesystem specific functions to be implemented.
- Current patch doesn't support VM_NONLINEAR - which can be addressed in
the future.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrea Arcangeli <andrea@suse.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On most powerpc CPUs, the dcache and icache are not coherent so
between writing and executing a page, the caches must be flushed.
Userspace programs assume pages given to them by the kernel are icache
clean, so we must do this flush between the kernel clearing a page and
it being mapped into userspace for execute. We were not doing this
for hugepages, this patch corrects the situation.
We use the same lazy mechanism as we use for normal pages, delaying
the flush until userspace actually attempts to execute from the page
in question.
Tested on G5.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Blah. The patch [0] I recently sent fixing errors with
in_hugepage_area() and prepare_hugepage_range() for powerpc itself has
an off-by-one bug. Furthermore, the related functions
touches_hugepage_*_range() and within_hugepage_*_range() are also
buggy. Some of the bugs, like those addressed in [0] originated with
commit 7d24f0b8a5 where we tweaked the
semantics of where hugepages are allowed. Other bugs have been there
essentially forever, and are due to the undefined behaviour of '<<'
with shift counts greater than the type width (LOW_ESID_MASK could
return non-zero for high ranges with the right congruences).
The good news is that I now have a testsuite which should pick up
things like this if they creep in again.
[0] "powerpc-fix-for-hugepage-areas-straddling-4gb-boundary"
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 7d24f0b8a5 fixed bugs in the ppc64 SLB
miss handler with respect to hugepage handling, and in the process tweaked
the semantics of the hugepage address masks in mm_context_t.
Unfortunately, it left out a couple of necessary changes to go with that
change. First, the in_hugepage_area() macro was not updated to match,
second prepare_hugepage_range() was not updated to correctly handle
hugepages regions which straddled the 4GB point.
The latter appears only to cause process-hangs when attempting to map such
a region, but the former can cause oopses if a get_user_pages() is
triggered at the wrong point. This patch addresses both bugs.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Email address update, changing old work address to personal (permanent)
one.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The result is mostly similar to the original ppc64 version but with
some adaptations for 32-bit compilation.
include/asm-ppc64 is now empty!
Signed-off-by: Paul Mackerras <paulus@samba.org>
This involves some minor changes: a few unused functions that the
ppc32 pci.c provides are no longer declared here or exported;
pcibios_assign_all_busses now just refers to the pci_assign_all_buses
variable on both 32-bit and 64-bit; pcibios_scan_all_fns is now
just 0 instead of a function that always returns 0 on 64-bit.
Signed-off-by: Paul Mackerras <paulus@samba.org>
For these, I have just done the lame-o merge where the file ends up
looking like:
#ifndef CONFIG_PPC64
#include <asm-ppc/foo.h>
#else
... contents from asm-ppc64/foo.h
#endif
so nothing has changed, really, except that we reduce include/asm-ppc64
a bit more.
Signed-off-by: Paul Mackerras <paulus@samba.org>
With the new powerpc architecture we don't seem to be able to disable huge
pages anymore.
mm/built-in.o(.toc1+0xae0): undefined reference to `HPAGE_SHIFT'
make: *** [.tmp_vmlinux1] Error 1
We seem to need to define HPAGE_SHIFT to something when HUGETLB_PAGE isn't
defined. This patch defines it to PAGE_SHIFT when we have no support.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch merges align.c, the result isn't quite what was in ppc64 nor
what was in ppc32 :) It should implement all the functionalities of both
though. Kumar, since you played with that in the past, I suppose you
have some test cases for verifying that it works properly before I dig
out the 601 machine ? :)
Since it's likely that I won't be able to test all scenario, code
inspection is much welcome.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
My earlier merge of delay.h introduced a timebase-based udelay for
32-bit machines but also broke the 601, which doesn't have the
timebase register. This fixes it by using the 601's RTC register on
the 601, and also moves __delay() and udelay() to be out-of-line in
arch/powerpc/kernel/time.c. These functions aren't really performance
critical, after all.
Signed-off-by: Paul Mackerras <paulus@samba.org>
The fix to topology.h (5cfccd7f13) seems to have
a typeo, struct sched_domain has an idle_idx member but not an idle_id
member. I assume this is the fix.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If the kernel supports both G5 and pSeries, and CONFIG_EEH is enabled,
eeh_init() is (quite reasonably) never called when we boot on a G5. Yet
eeh_check_failure() still gets called. We should avoid doing that if
!eeh_subsystem_enabled.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
PowerPC's NUMA domain doesn't currently set up some of the newer
sched-domains parameters.
Brian Twichell <tbrian@us.ibm.com> discovered and diagnosed a 1.5% OLTP
database regression on a 4 core POWER5 system that was due to the use of
NUMA scheduling on ppc64.
This patch applies some saneish values to the parameters, in line with
other architectures. This solves the regression.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The vDSO functions should have the same calling convention as a syscall.
Unfortunately, they currently don't set the cr0.so bit which is used to
indicate an error. This patch makes them clear this bit unconditionally
since all functions currently succeed. The syscall fallback done by some
of them will eventually override this if the syscall fails.
This also changes the symbol version of all vdso exports to make sure
glibc can differenciate between old and fixed calls for existing ones
like __kernel_gettimeofday.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
I discovered that in some cases (PowerMac for example) we wouldn't
properly map the PCI IO space on recent kernels. In addition, the code
for initializing PCI host bridges was scattered all over the place with
some duplication between platforms.
This patch fixes the problem and does a small cleanup by creating a
pcibios_alloc_controller() in pci_64.c that is similar to the one in
pci_32.c (just takes an additional device node argument) that takes care
of all the grunt allocation and initialisation work. It should work for
both boot time and dynamically allocated PHBs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
... and also delete some that are no longer used because we already
had an include/asm-powerpc version of the header.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes various errors in the new functions added in the vDSO's,
I've now verified all functions on both 32 and 64 bits vDSOs. It also
fix a sign extension bug getting the initial time of day at boot that
could cause the monotonic clock value to be completely on bogus for
64 bits applications (with either the vDSO or the syscall) on
powermacs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The userspace kexec-tools need to know the location of the htab on non-lpar
machines, as well as the end of the kernel. Export via the device tree.
NB. This patch has been updated to use "linux,x" property names. You may
need to update your kexec-tools to match.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently have a ppc_md member called cpu_irq_down, which disables IRQs
for the cpu in question. The only caller of cpu_irq_down is the kexec code.
On pSeries we need to do more than just teardown IRQs at kexec time, so rename
the ppc_md member to kexec_cpu_down and expand it. The pSeries code needs to
know, and other platforms might too, whether we're doing a crash shutdown (ie.
panicking) or a regular kexec, so add a flag for that.
The pSeries implementation of kexec_cpu_down does an unregister VPA call, which
tells the Hypervisor to stop writing stuff into our pacas. Without this we can
get weird memory corruption bugs when we kexec, caused by the Hypervisor
writing into the first kernel's pacas which happens to be somewhere interesting
in the second kernel's memory.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Merge asm-ppc/page.h and asm-ppc64/page.h into asm-powerpc/page.h,
asm-powerpc/page_32.h and asm-powerpc/page_64.h
Built for PPC (common_defconfig), with ARCH=powerpc, mostly built with
ARCH=ppc (other things break the build). Built and booted on P5 LPAR
for PPC64 with ARCH=ppc/powerpc (pseries_defconfig). Mostly built for
iSeries powerpc.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Introduce an atomic_inc_not_zero operation. Make this a special case of
atomic_add_unless because lockless pagecache actually wants
atomic_inc_not_negativeone due to its offset refcount.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch moves the vdso's to arch/powerpc, adds support for the 32
bits vdso to the 32 bits kernel, rename systemcfg (finally !), and adds
some new (still untested) routines to both vdso's: clock_gettime() with
support for CLOCK_REALTIME and CLOCK_MONOTONIC, clock_getres() (same
clocks) and get_tbfreq() for glibc to retreive the timebase frequency.
Tom,Steve: The implementation of get_tbfreq() I've done for 32 bits
returns a long long (r3, r4) not a long. This is such that if we ever
add support for >4Ghz timebases on ppc32, the userland interface won't
have to change.
I have tested gettimeofday() using some glibc patches in both ppc32 and
ppc64 kernels using 32 bits userland (I haven't had a chance to test a
64 bits userland yet, but the implementation didn't change and was
tested earlier). I haven't tested yet the new functions.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Since the udbg code in ppc64 has no ppc32 equivalent, move it straight
over into arch/powerpc (and include/asm-powerpc for udbg.h). In time,
we probably want to meld the various bits and pieces of 32-bit early
debugging code into udbg, but for now only include it on
CONFIG_PPC64=y builds. The only change during the move is to
standardise the protecting #ifdef/#define in udbg.h, and move its
banner comment above the initial #ifdef (which seems to be normal
practice).
Built and booted on POWER5 LPAR (ARCH=powerpc and ARCH=ppc64). Built
for 32bit multiplatform (ARCH=powerpc).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The definitions in sparsemem.h arent sufficient. We currently sell
machines with 2TB of RAM, and in order to give us room for a few years
growth lets set it to 16TB.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Convert to sparsemem and remove all the discontigmem code in the
process. This has a few advantages:
- The old numa_memory_lookup_table can go away
- All the arch specific discontigmem magic can go away
We also remove the triple pass of memory properties and instead create a
list of per node extents that we iterate through. A final cleanup would
be to change our lmb code to store extents per node, then we can reuse
that information in the numa code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove ppc64 specific version of nr_cpus_node and use the generic one
provided.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The bit position in the status register corresponding to the
PCI DMA interrupt was incorrect. Additionally, we did not
have a define for the PCI DMA interrupt.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
17-eeh-slot-marking-bug.patch
A device that experiences a PCI outage may be just one deivce out
of many that was affected. In order to avoid repeated reports of
a failure, the entire tree of affected devices should be marked
as failed. This patch marks up the entire tree.
Signed-off-by: Linas Vepstas <linas@linas.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This also make klimit have the same type on 32-bit as on 64-bit,
namely unsigned long, and defines and initializes it in one place.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch moves a bunch more files from arch/ppc64 and
include/asm-ppc64 which have no equivalents in ppc32 code into
arch/powerpc and include/asm-powerpc. The file affected are:
hvcall.h
proc_ppc64.c
sysfs.c
lparcfg.c
rtas_pci.c
The only changes apart from the move and corresponding Makefile
changes are:
- #ifndef/#define in includes updated to _ASM_POWERPC_ form
- trailing whitespace removed
- comments giving full paths removed
Built and booted on POWER5 LPAR (ARCH=powerpc and ARCH=ppc64), built
for 32-bit powermac (ARCH=powerpc).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is at the request of the glibc folks, who want to use these bits
to select libraries optimized for the microarchitecture and new
instructions in these processors.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch merges platform codes. systemcfg->platform is no longer used,
systemcfg use in general is deprecated as much as possible (and renamed
_systemcfg before it gets completely moved elsewhere in a future patch),
_machine is now used on ppc64 along as ppc32. Platform codes aren't gone
yet but we are getting a step closer. A bunch of asm code in head[_64].S
is also turned into C code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch consolidates macros used to generate assembly for
compatibility across different CPUs or configs. A new header,
asm-powerpc/asm-compat.h contains the main compatibility macros. It
uses some preprocessor magic to make the macros suitable both for use
in .S files, and in inline asm in .c files. Headers (bitops.h,
uaccess.h, atomic.h, bug.h) which had their own such compatibility
macros are changed to use asm-compat.h.
ppc_asm.h is now for use in .S files *only*, and a #error enforces
that. As such, we're a lot more careless about namespace pollution
here than in asm-compat.h.
While we're at it, this patch adds a call to the PPC405_ERR77 macro in
futex.h which should have had it already, but didn't.
Built and booted on pSeries, Maple and iSeries (ARCH=powerpc). Built
for 32-bit powermac (ARCH=powerpc) and Walnut (ARCH=ppc).
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The ppc32 and ppc64 versions of cacheflush.h were almost identical.
The two versions of cache.h are fairly similar, except for a bunch of
register definitions in the ppc32 version which probably belong better
elsewhere. This patch, therefore, merges both headers. Notable
points:
- there are several functions in cacheflush.h which exist only
on ppc32 or only on ppc64. These are handled by #ifdef for now, but
these should probably be consolidated, along with the actual code
behind them later.
- Confusingly, both ppc32 and ppc64 have a
flush_dcache_range(), but they're subtly different: it uses dcbf on
ppc32 and dcbst on ppc64, ppc64 has a flush_inval_dcache_range() which
uses dcbf. These too should be merged and consolidated later.
- Also flush_dcache_range() was defined in cacheflush.h on
ppc64, and in cache.h on ppc32. In the merged version it's in
cacheflush.h
- On ppc32 flush_icache_range() is a normal function from
misc.S. On ppc64, it was wrapper, testing a feature bit before
calling __flush_icache_range() which does the actual flush. This
patch takes the ppc64 approach, which amounts to no change on ppc32,
since CPU_FTR_COHERENT_ICACHE will never be set there, but does mean
renaming flush_icache_range() to __flush_icache_range() in
arch/ppc/kernel/misc.S and arch/powerpc/kernel/misc_32.S
- The PReP register info from asm-ppc/cache.h has moved to
arch/ppc/platforms/prep_setup.c
- The 8xx register info from asm-ppc/cache.h has moved to a
new asm-powerpc/reg_8xx.h, included from reg.h
- flush_dcache_all() was defined on ppc32 (only), but was
never called (although it was exported). Thus this patch removes it
from cacheflush.h and from ARCH=powerpc (misc_32.S) entirely. It's
left in ARCH=ppc for now, with the prototype moved to ppc_ksyms.c.
Built for Walnut (ARCH=ppc), 32-bit multiplatform (pmac, CHRP and PReP
ARCH=ppc, pmac and CHRP ARCH=powerpc). Built and booted on POWER5
LPAR (ARCH=powerpc and ARCH=ppc64).
Built for 32-bit powermac (ARCH=ppc and ARCH=powerpc). Built and
booted on POWER5 LPAR (ARCH=powerpc and ARCH=ppc64). Built and booted
on G5 (ARCH=powerpc)
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
14-eeh-device-bar-save.patch
After a PCI device has been resest, the device BAR's and other config
space info must be restored to the same state as they were in when
the firmware first handed us this device. This will allow the
PCI device driver, when restarted, to correctly recognize and set up
the device.
Tis patch saves the device config space as early as reasonable after
the firmware has handed over the device. Te state resore funcion
is inteded for use by the EEH recovery routines.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
13-eeh-recovery-support-routines.patch
EEH Recovery support routines
This patch adds routines required to help drive the recovery of
EEH-frozen slots. The main function is to drive the PCI #RST
signal line high for a qurter of a second, and then allow for
a second & a half of settle time.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
12-eeh-event-dispatcher.patch
ppc64: EEH Recovery dispatcher thread
This patch adds a mechanism to create recovery threads when an
EEH event is received. Since an EEH freeze state may be detected
within an interrupt context, we need to get out of the interrupt
context before starting recovery. This dispatcher does this in
two steps: first, it uses a workqueue to get out, and then
lanuches a kernel thread, so that the recovery routine can
sleep for exteded periods without upseting the keventd.
A kernel thread is created with each EEH event, rather than
having one long-running daemon started at boot time. This is
because it is anticipated that EEH events will be very rare
(very very rare, ideally) and so its pointless to cluter the
process tables with a daemon that will almost never run.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
03-eeh-addr-cache-cleanup.patch
This is a minor patch to clean up a buglet related to the PCI address cache.
(The buglet doesn't manifes itself unless there are also bugs elsewhere,
which is why its minor.). Also:
-- Improved debug printing.
-- Declare some private routines as static
-- Adds reference counting to struct pci_dn->pcidev structure
Signed-off-by: Linas Vepstas <linas@linas.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Badari Pulavarty
Stephen Hemminger
David Gibson
Paul Mackerras
Olof Johansson
Andy Whitcroft
Stephen Rothwell
Benjamin Herrenschmidt
Michael Ellerman
David Woodhouse
Nick Piggin
Anton Blanchard
Kumar Gala
Linas Vepstas