Remove debug printks in pseries_mach_cpu_die(). These are
noisy at runtime. Traceevents can be added to instrument this
section of code.
The following KERN_INFO printks are removed:
cpu 62 (hwid 62) returned from cede.
Decrementer value = b2802fff Timebase value = 2fa8f95035f4a
cpu 62 (hwid 62) got prodded to go online
cpu 58 (hwid 58) ceding for offline with hint 2
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rearrange condition checks for better code readability and
prevention of possible race conditions when
preferred_offline_state can potentially change during the
execution of pseries_mach_cpu_die(). The patch will make
pseries_mach_cpu_die() put cpu in one of the consistent states
and not hit the run over BUG()
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cpu hotplug (offline) without dlpar operation will place cpu
in cede state and the extended_cede_processor() function will
return when resumed.
Kernel stack pointer needs to be reset before
start_secondary() is called to continue the online operation.
Added new function start_secondary_resume() to do the above
steps.
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that we properly keep track of the CPPR value (since
49bd364713, "powerpc/pseries: Track previous
CPPR values to correctly EOI interrupts") we can pass it to the
H_XIRR hcall.
This is needed because the Partition Adjunct Option of new versions of
pHyp extend the H_XIRR hcall to include the CPPR as an input parameter.
Earlier versions not supporting this option just disregard the extra
input parameter, so this doesn't cause any problems for existing systems.
The Partition Adjunct Option is required for future systems that will
support SR-IOV capable devices.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Compiling 2.6.33 with SMP enabled and HOTPLUG_CPU disabled gives me the
following link errors:
LD init/built-in.o
LD .tmp_vmlinux1
arch/powerpc/platforms/built-in.o: In function `.smp_xics_setup_cpu':
smp.c:(.devinit.text+0x88): undefined reference to `.set_cpu_current_state'
smp.c:(.devinit.text+0x94): undefined reference to `.set_default_offline_state'
arch/powerpc/platforms/built-in.o: In function `.smp_pSeries_kick_cpu':
smp.c:(.devinit.text+0x13c): undefined reference to `.set_preferred_offline_state'
smp.c:(.devinit.text+0x148): undefined reference to `.get_cpu_current_state'
smp.c:(.devinit.text+0x1a8): undefined reference to `.get_cpu_current_state'
make: *** [.tmp_vmlinux1] Error 1
The following change fixes that for me and seems to work as expected.
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
confirm_error_lock needs to be a real spinlock in RT. Convert it to
raw_spinlock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now we use printf style alignment there is no need to manually space
these fields.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Right now we allocate a cacheline sized NR_CPUS array for xics IPI
communication. Use DECLARE_PER_CPU_SHARED_ALIGNED to put it in percpu
data in its own cacheline since it is written to by other cpus.
On a kernel with NR_CPUS=1024, this saves quite a lot of memory:
text data bss dec hex filename
8767779 2944260 1505724 13217763 c9afe3 vmlinux.irq_cpustat
8767555 2813444 1505724 13086723 c7b003 vmlinux.xics
A saving of around 128kB.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During a EEH recover, the pci_dev structure can be null, mainly if an
eeh event is detected during cpi config operation. In this case, the
pci_dev will not be known (and will be null) the kernel will crash
with the following message:
Unable to handle kernel paging request for data at address 0x000000a0
Faulting instruction address: 0xc00000000006b8b4
Oops: Kernel access of bad area, sig: 11 [#1]
NIP [c00000000006b8b4] .eeh_event_handler+0x10c/0x1a0
LR [c00000000006b8a8] .eeh_event_handler+0x100/0x1a0
Call Trace:
[c0000003a80dff00] [c00000000006b8a8] .eeh_event_handler+0x100/0x1a0
[c0000003a80dff90] [c000000000031f1c] .kernel_thread+0x54/0x70
The bug occurs because pci_name() tries to access a null pointer.
This patch just guarantee that pci_name() is not called on Null pointers.
Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Frans Pop <elendil@planet.nl>
Cc: linuxppc-dev@ozlabs.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The cede latency stuff is relatively new and we don't need to complain about
it not working on older firmware.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
String constants that are continued on subsequent lines with \
are not good.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The tb_total and purr_total values reported via the hcall_stats code
should be cumulative, rather than being replaced by the latest delta tb
or purr value.
Tested-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Acked-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The code to track the CPPR values added by commit
49bd364713 ("powerpc/pseries: Track previous
CPPR values to correctly EOI interrupts") broke kexec on pseries because
the kexec code in xics.c calls xics_set_cpu_priority() before the IPI has
been EOI'ed. This wasn't a problem previously but it now triggers a BUG_ON
in xics_set_cpu_priority() because os_cppr->index isn't 0.
Fix this problem by setting the index on the CPPR stack to 0 before calling
xics_set_cpu_priority() in xics_teardown_cpu().
Also make it clear that we only want to set the priority when there's just
one CPPR value in the stack, and enforce it by updating the value of
os_cppr->stack[0] rather than os_cppr->stack[os_cppr->index].
While we're at it change the BUG_ON to a WARN_ON.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
desc->affinity doesn't exit in that case. Let's use a macro for
the UP variant of get_irq_server(), it's the easiest way, avoids
evaluating arguments.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Move the defintion and lock helper routines for the cpu hotplug driver
lock from pseries to powerpc code to avoid build breaks for platforms
other than pseries that use cpu hotplug.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 57b150cce8 (irq: only update affinity if
->set_affinity() is sucessfull) broke xics irq affinity.
We need to use the cpumask passed in, instead of accessing ->affinity directly.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
And add the __acquires() and __releases() annotations, while at it.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If an online-attempt on a CPU which has been offlined using H_CEDE
with an appropriate cede latency hint fails, don't panic.
Instead print the error message and let the __cpu_up() code notify the
CPU Hotplug framework of the failure, which in turn can notify the
other subsystem through CPU_UP_CANCELED.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It's possible to set CONFIG_XICS without CONFIG_PCI_MSI. When that happens,
the kernel fails to build with
arch/powerpc/platforms/built-in.o: In function `.xics_startup':
xics.c:(.text+0x12f60): undefined reference to `.unmask_msi_irq' make: ***
[.tmp_vmlinux1] Error 1
Furthermore, as noted by Benjamin Herrenschmidt, "CONFIG_XICS should be
made invisible and selected by PSERIES."
This patch fixes PSERIES to select both options
Signed-off-by: Mel Gorman <mel[at]csn.ul.ie>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The Collaborative Memory Manager (CMM) module allocates individual pages
over time that are not migratable. On a long running system this can
severely impact the ability to find enough pages to support a hotplug
memory remove operation.
This patch adds a memory isolation notifier and a memory hotplug notifier.
The memory isolation notifier will return the number of pages found in
the range specified. This is used to determine if all of the used pages
in a pageblock are owned by the balloon (or other entities in the notifier
chain). The hotplug notifier will free pages in the range which is to be
removed. The priority of this hotplug notifier is low so that it will be
called near last, this helps avoids removing loaned pages in operations
that fail due to other handlers.
CMM activity will be halted when hotplug remove operations are active and
resume activity after a delay period to allow the hypervisor time to
adjust.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Brian King <brking@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Gerald Schaefer <geralds@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Convert locks which cannot be sleeping locks in preempt-rt to
raw_spinlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
m68k: rename global variable vmalloc_end to m68k_vmalloc_end
percpu: add missing per_cpu_ptr_to_phys() definition for UP
percpu: Fix kdump failure if booted with percpu_alloc=page
percpu: make misc percpu symbols unique
percpu: make percpu symbols in ia64 unique
percpu: make percpu symbols in powerpc unique
percpu: make percpu symbols in x86 unique
percpu: make percpu symbols in xen unique
percpu: make percpu symbols in cpufreq unique
percpu: make percpu symbols in oprofile unique
percpu: make percpu symbols in tracer unique
percpu: make percpu symbols under kernel/ and mm/ unique
percpu: remove some sparse warnings
percpu: make alloc_percpu() handle array types
vmalloc: fix use of non-existent percpu variable in put_cpu_var()
this_cpu: Use this_cpu_xx in trace_functions_graph.c
this_cpu: Use this_cpu_xx for ftrace
this_cpu: Use this_cpu_xx in nmi handling
this_cpu: Use this_cpu operations in RCU
this_cpu: Use this_cpu ops for VM statistics
...
Fix up trivial (famous last words) global per-cpu naming conflicts in
arch/x86/kvm/svm.c
mm/slab.c
At the moment when we EOI an interrupt we set the CPPR back to 0xFF
regardless of its previous value. This could lead to problems if we
take an interrupt with a priority of 5, but before EOIing it we get
an IPI which has a priority of 4. The problem is that at the moment
when we EOI the IPI we will set the CPPR to 0xFF, but it should
really be set back to 5 (the previous priority).
To keep track of the previous CPPR values we create the xics_cppr
structure that has an array for CPPR values and an index pointing
to the current priority. This can easily grow if new priorities get
added in the future.
This will also be useful because the partition adjunct option of
upcoming machines will update the H_XIRR hcall to accept the CPPR
as a parameter.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The recent patch to add cpu offline/online as part of the DLPAR
process for pseries causes a build break if CONFIG_SMP is not
defined. Original patch here;
http://lists.ozlabs.org/pipermail/linuxppc-dev/2009-November/078299.html
This corrects the build break by moving the online_node_cpus
and offline_node_cpus under the #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
portions of dlpar.c.
This patch also slightly modifies the online_node_cpus and offline_node_cpus
routines to prepend dlpar_ to the them and make them static. These two
routine are only used in the dlpar add/remove of cpus and these changes
should help clarify that.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Writing a driver using SCLPC on the MPC5200B I detected, that the
intspec arrays to map irqs to Linux virq cannot be const, because the
mapping and xlate functions only take non const pointers. All those
functions do not modify the intspec, so a const pointer could be used.
Signed-off-by: Roman Fietze <roman.fietze@telemotive.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently the cpu-allocation/deallocation process comprises of two steps:
- Set the indicators and to update the device tree with DLPAR node
information.
- Online/offline the allocated/deallocated CPU.
This is achieved by writing to the sysfs tunables "probe" during allocation
and "release" during deallocation.
At the sametime, the userspace can independently online/offline the CPUs of
the system using the sysfs tunable "online".
It is quite possible that when a userspace tool offlines a CPU
for the purpose of deallocation and is in the process of updating the device
tree, some other userspace tool could bring the CPU back online by writing to
the "online" sysfs tunable thereby causing the deallocate process to fail.
The solution to this is to serialize writes to the "probe/release" sysfs
tunable with the writes to the "online" sysfs tunable.
This patch employs a mutex to provide this serialization, which is a no-op on
all architectures except PPC_PSERIES
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently the cpu-allocation/deallocation on pSeries is a
two step process from the Userspace.
- Set the indicators and update the device tree by writing to the sysfs
tunable "probe" during allocation and "release" during deallocation.
- Online / Offline the CPUs of the allocated/would_be_deallocated node by
writing to the sysfs tunable "online".
This patch adds kernel code to online/offline the CPUs soon_after/just_before
they have been allocated/would_be_deallocated. This way, the userspace tool
that performs DLPAR operations would only have to deal with one set of sysfs
tunables namely "probe" and release".
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds the specific routines to probe and release (add and remove)
cpu resource for the powerpc pseries platform and registers these handlers
with the ppc_md callout structure.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The Dynamic Logical Partitioning capabilities of the powerpc pseries platform
allows for the addition and removal of resources (i.e. CPU's, memory, and PCI
devices) from a partition. The removal of a resource involves
removing the resource's node from the device tree and then returning the
resource to firmware via the rtas set-indicator call. To add a resource, it
is first obtained from firmware via the rtas set-indicator call and then a
new device tree node is created using the ibm,configure-coinnector rtas call
and added to the device tree.
This patch provides the kernel DLPAR infrastructure in a new filed named
dlpar.c. The functionality provided is for acquiring and releasing a resource
from firmware and the parsing of information returned from the
ibm,configure-connector rtas call. Additionally this exports the pSeries
reconfiguration notifier chain so that it can be invoked when device tree
updates are made.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When a CPU is offlined on POWER currently, we call rtas_stop_self() and hand
the CPU back to the resource pool. This path is used for DLPAR which will
cause a change in the LPAR configuration which will be visible outside.
This patch changes the default state a CPU is put into when it is offlined.
On platforms which support ceding the processor to the hypervisor with
latency hint specifier value, during a cpu offline operation,
instead of calling rtas_stop_self(), we cede the vCPU to the hypervisor
while passing a latency hint specifier value. The Hypervisor can use this hint
to provide better energy savings. Also, during the offline
operation, the control of the vCPU remains with the LPAR as oppposed to
returning it to the resource pool.
The patch achieves this by creating an infrastructure to set the
preferred_offline_state() which can be either
- CPU_STATE_OFFLINE: which is the current behaviour of calling
rtas_stop_self()
- CPU_STATE_INACTIVE: which cedes the vCPU to the hypervisor with the latency
hint specifier.
The codepath which wants to perform a DLPAR operation can set the
preferred_offline_state() of a CPU to CPU_STATE_OFFLINE before invoking
cpu_down().
The patch also provides a boot-time command line argument to disable/enable
CPU_STATE_INACTIVE.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
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>
The typename member of struct irq_chip was kept for migration purposes
and is obsolete since more than 2 years. Fix up the leftovers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org
Acked-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Patch f598282f51 exposed a problem in
powerpc MSI-X functionality, making network interfaces such as ixgbe
and cxgb3 stop to work when MSI-X is enabled. RX interrupts were not
being generated.
The problem was caused because MSI irq was not being effectively
unmasked after device initialization.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When running Active Memory Sharing, the Collaborative Memory Manager (CMM)
may mark some pages as "loaned" with the hypervisor. Periodically, the
CMM will query the hypervisor for a loan request, which is a single signed
value. When kexec'ing into a kdump kernel, the CMM driver in the kdump
kernel is not aware of the pages the previous kernel had marked as "loaned",
so the hypervisor and the CMM driver are out of sync. Fix the CMM driver
to handle this scenario by ignoring requests to decrease the number of loaned
pages if we don't think we have any pages loaned. Pages that are marked as
"loaned" which are not in the balloon will automatically get switched to "active"
the next time we touch the page. This also fixes the case where totalram_pages
is smaller than min_mem_mb, which can occur during kdump.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
get_irq_desc() is a powerpc-specific version of irq_to_desc(). That
is reason enough to remove it, but it also doesn't know about sparse
irq_desc support which irq_to_desc() does (when we enable it).
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rather than open-coding our own check, use irq_has_action()
to check if an irq has an action - ie. is "in use".
irq_has_action() doesn't take the descriptor lock, but it
shouldn't matter - we're just using it as an indicator
that the irq is in use. disable_irq_nosync() will take
the descriptor lock before doing anything also.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The CHRP code has some fishy timer based code to scan the RTAS event
log, which uses a 1KB stack buffer and doesn't even use the results.
The pSeries code as a nicer daemon that allows userspace to read the
event log and basically uses the same RTAS interface
This patch moves rtasd.c out of platform/pseries and makes it usable
by CHRP, after removing the old crufty event log mechanism in there.
The nvram logging part of the daemon is still only available on 64-bit
since the underlying nvram management routines aren't currently shared.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some of the stuff in /proc/ppc64 such as the RTAS bits are actually
useful to some 32-bit platforms. Rename the file, and create a
symlink on 64-bit for backward compatibility
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch updates percpu related symbols in powerpc such that percpu
symbols are unique and don't clash with local symbols. This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.
* arch/powerpc/kernel/perf_callchain.c: s/callchain/cpu_perf_callchain/
* arch/powerpc/kernel/setup-common.c: s/pvr/cpu_pvr/
* arch/powerpc/platforms/pseries/dtl.c: s/dtl/cpu_dtl/
* arch/powerpc/platforms/cell/interrupt.c: s/iic/cpu_iic/
Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.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>
Profiling of a page fault scalability microbenchmark shows flush_hash_range
is not calling the batch hpte invalidate hcall (H_BULK_REMOVE).
It turns out we have a duplicate firmware feature for hcall-bulk and the
current setup code stops after finding the first match. This meant we never
batch and always do individual invalidates.
The patch below removes the duplicate and shifts FW_FEATURE_CMO to close
the gap. With the patch applied the single threaded page fault rate improves
from 217169 to 238755 per second on a POWER5 test box, a 10% improvement.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Sometimes this is used to hold a simple offset, and sometimes
it is used to hold a pointer. This patch changes it to a union containing
void * and dma_addr_t. get/set accessors are also provided, because it was
getting a bit ugly to get to the actual data.
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Vaidyanathan Srinivasan