Between GCC version 3.4.0 and 4.3.3 (including 3.4.0 and 4.3.3), -mtune=merced
is implemented in GCC. Starting from 4.4.0, -mtune=merced is deprecated.
Even implemented in versions between 3.4.0 and 4.3.3, the -mtune=merced
feature has been broken in some of the versions. For example, GCC 4.1.2 reports
interanl tuning function errors during kernel building with -mtune=merced. Or
GCC Bugzilla 16130 reports another -mtune=merced issue on GCC 3.4.1.
So I would remove the -mtune=merced from IA64 kernel build. Without this option,
kernel on Merced will remain the same except losing an unstable and out-of-date
performance tunning feature.
Since GCC version 3.4.0, -mtune=mckinley has been implemented. The
-mtune=mckinley option functions the same as mtune=itanium2. And mtune=itanium2
is the default option. So we don't need to add mtune=mckinley either since its
been the default option in any GCC version which implements this option.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/include/asm/pgtable.h: asm/processor.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/kernel/ia64_ksyms.c: asm/page.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
__test_and_clear_bit() returns a bitfield with the tested-for bit set.
Make it consistent with the other bitops - of ia64 but also every
other architecture - and return a boolean value.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
In commit 160c1d8e40,
dma_ops->dma_supported = iommu_dma_supported;
This dma_ops->dma_supported is first called in platform_dma_init() during kernel
boot. Then dma_ops->dma_supported will be called recursively in
iommu_dma_supported.
Kernel can not boot because kernel can not get out of iommu_dma_supported until
it runs out of stack memory.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Fix memory leakage in /security/selinux/hooks.c
The buffer always needs to be freed here; we either error
out or allocate more memory.
Reported-by: iceberg <strakh@ispras.ru>
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Commit 783ea7d4ee
(Driver Core: Rework platform suspend/resume, print warning)
added a warning message printed for platform drivers that use the
legacy PM callbacks rather than struct dev_pm_ops. Unfortunately,
this resulted in some confusion and made some people try to convert
drivers by replacing the old callbacks with struct dev_pm_ops in
automatic way, which generally is not a good idea.
Remove the platform device runtime dev_pm_ops warning for now,
because it's annoying to users and it's not really necessary right
now.
[rjw: Modified the changelog to be more informative.]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Commit d945cb9cc ("pty: Rework the pty layer to use the normal buffering
logic") dropped the test for 'tty->stopped' in pty_write_room(), which
then causes the n_tty line discipline thing to not throttle the data
properly when the tty is stopped.
So instead of pausing the write due to the tty being stopped, the ldisc
layer would go ahead and push it down to the pty. The pty write()
routine would then refuse to take the data (because it _did_ check
'stopped'), and the data wouldn't actually be written.
This whole stopped test should eventually be moved into the tty ldisc
layer rather than have low-level tty drivers care about these things,
but right now the fix is to just re-instate the missing pty 'stopped'
handling.
Reported-and-tested-by: Artur Skawina <art.08.09@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (27 commits)
perf_counter: Zero dead bytes from ftrace raw samples size alignment
perf_counter: Subtract the buffer size field from the event record size
perf_counter: Require CAP_SYS_ADMIN for raw tracepoint data
perf_counter: Correct PERF_SAMPLE_RAW output
perf tools: callchain: Fix bad rounding of minimum rate
perf_counter tools: Fix libbfd detection for systems with libz dependency
perf: "Longum est iter per praecepta, breve et efficax per exempla"
perf_counter: Fix a race on perf_counter_ctx
perf_counter: Fix tracepoint sampling to be part of generic sampling
perf_counter: Work around gcc warning by initializing tracepoint record unconditionally
perf tools: callchain: Fix sum of percentages to be 100% by displaying amount of ignored chains in fractal mode
perf tools: callchain: Fix 'perf report' display to be callchain by default
perf tools: callchain: Fix spurious 'perf report' warnings: ignore empty callchains
perf record: Fix the -A UI for empty or non-existent perf.data
perf util: Fix do_read() to fail on EOF instead of busy-looping
perf list: Fix the output to not include tracepoints without an id
perf_counter/powerpc: Fix oops on cpus without perf_counter hardware support
perf stat: Fix tool option consistency: rename -S/--scale to -c/--scale
perf report: Add debug help for the finding of symbol bugs - show the symtab origin (DSO, build-id, kernel, etc)
perf report: Fix per task mult-counter stat reporting
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI hotplug: SGI hotplug: do not use hotplug_slot_attr
PCI hotplug: SGI hotplug: fix build failure
Wei Chong Tan reported a fast-PIT-calibration corner-case:
| pit_expect_msb() is vulnerable to SMI disturbance corner case
| in some platforms which causes /proc/cpuinfo to show wrong
| CPU MHz value when quick_pit_calibrate() jumps to success
| section.
I think that the real issue isn't even an SMI - but the fact
that in the very last iteration of the loop, there's no
serializing instruction _after_ the last 'rdtsc'. So even in
the absense of SMI's, we do have a situation where the cycle
counter was read without proper serialization.
The last check should be done outside the outer loop, since
_inside_ the outer loop, we'll be testing that the PIT has
the right MSB value has the right value in the next iteration.
So only the _last_ iteration is special, because that's the one
that will not check the PIT MSB value any more, and because the
final 'get_cycles()' isn't serialized.
In other words:
- I'd like to move the PIT MSB check to after the last
iteration, rather than in every iteration
- I think we should comment on the fact that it's also a
serializing instruction and so 'fences in' the TSC read.
Here's a suggested replacement.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: "Tan, Wei Chong" <wei.chong.tan@intel.com>
Tested-by: "Tan, Wei Chong" <wei.chong.tan@intel.com>
LKML-Reference: <B28277FD4E0F9247A3D55704C440A140D5D683F3@pgsmsx504.gar.corp.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
mm_for_maps: take ->cred_guard_mutex to fix the race with exec
mm_for_maps: shift down_read(mmap_sem) to the caller
mm_for_maps: simplify, use ptrace_may_access()
Fix the following 'make includecheck' warning:
arch/mn10300/include/asm/pci.h: linux/mm.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
clean up type-casting twice. "size_t" is typedef as "unsigned long" in
64-bit system, and "unsigned int" in 32-bit system, and the intermediate
cast to 'long' is pointless.
Signed-off-by: Figo.zhang <figo1802@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This will register the ioctl range used by nilfs2 file system to the
table listed in Documentation/ioctl/ioctl-number.txt.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We compute the perf raw sample size by aligning the raw ftrace
event size plus the buffer size field itself. We do that
instead of aligning only the perf raw sample size, so that we
might economize some in some cases.
But this buffer size field is not stored in the perf raw
sample, we must then substract its size from the buffer once we
computed the alignment unless we may get a useless u32 field in
the buffer.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20090810141129.GA5124@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The problem is minor, but without ->cred_guard_mutex held we can race
with exec() and get the new ->mm but check old creds.
Now we do not need to re-check task->mm after ptrace_may_access(), it
can't be changed to the new mm under us.
Strictly speaking, this also fixes another very minor problem. Unless
security check fails or the task exits mm_for_maps() should never
return NULL, the caller should get either old or new ->mm.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
mm_for_maps() takes ->mmap_sem after security checks, this looks
strange and obfuscates the locking rules. Move this lock to its
single caller, m_start().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
It would be nice to kill __ptrace_may_access(). It requires task_lock(),
but this lock is only needed to read mm->flags in the middle.
Convert mm_for_maps() to use ptrace_may_access(), this also simplifies
the code a little bit.
Also, we do not need to take ->mmap_sem in advance. In fact I think
mm_for_maps() should not play with ->mmap_sem at all, the caller should
take this lock.
With or without this patch, without ->cred_guard_mutex held we can race
with exec() and get the new ->mm but check old creds.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Raw tracepoint data contains various kernel internals and
data from other users, so restrict this to CAP_SYS_ADMIN.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249896452.17467.75.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
PERF_SAMPLE_* output switches should unconditionally output the
correct format, as they are the only way to unambiguously parse
the PERF_EVENT_SAMPLE data.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249896447.17467.74.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On an iMac G5, the b43 driver is failing to initialise because trying to
set the dma mask to 30-bit fails. Even though there's only 512MiB of RAM
in the machine anyway:
https://bugzilla.redhat.com/show_bug.cgi?id=514787
We should probably let it succeed if the available RAM in the system
doesn't exceed the requested limit.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'kvm-updates/2.6.31' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: Avoid redelivery of edge interrupt before next edge
KVM: MMU: limit rmap chain length
KVM: ia64: fix build failures due to ia64/unsigned long mismatches
KVM: Make KVM_HPAGES_PER_HPAGE unsigned long to avoid build error on powerpc
KVM: fix ack not being delivered when msi present
KVM: s390: fix wait_queue handling
KVM: VMX: Fix locking imbalance on emulation failure
KVM: VMX: Fix locking order in handle_invalid_guest_state
KVM: MMU: handle n_free_mmu_pages > n_alloc_mmu_pages in kvm_mmu_change_mmu_pages
KVM: SVM: force new asid on vcpu migration
KVM: x86: verify MTRR/PAT validity
KVM: PIT: fix kpit_elapsed division by zero
KVM: Fix KVM_GET_MSR_INDEX_LIST
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
posix_cpu_timers_exit_group(): Do not use thread_group_cputimer()
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf_counter: Fix/complete ftrace event records sampling
perf_counter, ftrace: Fix perf_counter integration
tracing/filters: Always free pred on filter_add_subsystem_pred() failure
tracing/filters: Don't use pred on alloc failure
ring-buffer: Fix memleak in ring_buffer_free()
tracing: Fix recordmcount.pl to handle sections with only weak functions
ring-buffer: Fix advance of reader in rb_buffer_peek()
tracing: do not use functions starting with .L in recordmcount.pl
ring-buffer: do not disable ring buffer on oops_in_progress
ring-buffer: fix check of try_to_discard result
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: fix buffer overflow in efi_init()
x86: Add quirk to make Apple MacBookPro5,1 use reboot=pci
x86: Fix MSI-X initialization by using online_mask for x2apic target_cpus
x86: Fix VMI && stack protector
* 'core-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
lockdep: Fix typos in documentation
lockdep: Fix file mode of lock_stat
rtmutex: Avoid deadlock in rt_mutex_start_proxy_lock()
Sometimes we get callchain branches that have a rate under the
limit given by the user.
Say you launched:
perf record -f -g -a ./hackbench 10
perf report -g fractal,10.0
And you got:
2.33% hackbench [kernel] [k] _spin_lock_irqsave
|
|--78.57%-- remove_wait_queue
| poll_freewait
| do_sys_poll
| sys_poll
| sysenter_dispatch
| 0xf7ffa430
| 0x1ffadea3c
|
|--7.14%-- __up_read
| up_read
| do_page_fault
| page_fault
| 0xf7ffa430
| 0xa0df710000000a
...
It is abnormal to get a 7.14% branch whereas we passed a 10%
filter.
The problem is that we round down the minimum threshold. This
happens mostly when we have very low number of events. If the
total amount of your branch is 4 and you have a subranch of 3
events, filtering to 90% will be computed like follows:
limit = 4 * 0.9;
The result is about 3.6, but the cast to integer will round
down to 3. It means that our filter is actually of 75%
We must then explicitly round up the minimum threshold.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: acme@redhat.com
Cc: peterz@infradead.org
Cc: efault@gmx.de
LKML-Reference: <20090809024235.GA10146@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Due to a libz dependency in some distro's binutils package,
C++ demangle support isn't compiled in despite the necessary
libraries being available.
Fix this by adding a -lz link test to the dependency detection
rules.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1249733655.6929.5.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
A few examples of how 'perf' can be used, from an e-mail by
Ingo Molnar http://lkml.org/lkml/2009/8/4/346.
Signed-off-by: Carlos R. Mafra <crmafra2@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Valdis.Kletnieks@vt.edu
LKML-Reference: <20090805185334.GA4535@Pilar.aei.mpg.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While extending perfcounters with BTS hw-tracing, Markus
Metzger managed to trigger this warning:
[ 995.557128] WARNING: at kernel/perf_counter.c:1191 __perf_counter_task_sched_out+0x48/0x6b()
triggers because commit
9f498cc5be (perf_counter: Full
task tracing) removed clearing of tsk->perf_counter_ctxp out
from under ctx->lock which introduced a race (against
perf_lock_task_context).
Move it back and deal with the exit notification by explicitly
passing along the former task context.
Reported-by: Markus T Metzger <markus.t.metzger@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249667341.17467.5.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Based on Peter's comments, make tracepoint sampling generic
just like all the other sampling bits are. This is a rename
with no code changes:
- PERF_SAMPLE_TP_RECORD to PERF_SAMPLE_RAW
- struct perf_tracepoint_record to perf_raw_record
We want the system in place that transport tracepoints raw
samples events into the perf ring buffer to be generalized and
usable by any type of counter.
Reported-by; Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249698400-5441-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Despite that the tracepoint record is always present when the
PERF_SAMPLE_TP_RECORD flag is set, gcc raises a warning,
thinking it might not be initialized:
kernel/perf_counter.c: In function ‘perf_counter_output’:
kernel/perf_counter.c:2650: warning: ‘tp’ may be used uninitialized in this function
Then, initialize it to NULL and always check if it's not NULL
before dereference it.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249698400-5441-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When we filter the callchains below a given percentage, we
ignore them and the end result only shows entries that have an
upper percentage than the filter threshold.
It seems to users then that we have an imbalance in the
percentage, as if the sum inside a profiled branch doesn't
reach 100%.
Since in the past there have been real perf report bugs that
showed the same sypmtom, it would be nice to assure the user
that the data is perfect and trustable and it all sums up to
100.00%.
So fix this by displaying the remaining hits that have been
filtered but without more detail than their amount in each
branches. Example while filtering below 50%:
7.73% [k] delay_tsc
|
|--98.22%-- __const_udelay
| |
| |--86.37%-- ath5k_hw_register_timeout
| | ath5k_hw_noise_floor_calibration
| | ath5k_hw_reset
| | ath5k_reset
| | ath5k_config
| | ieee80211_hw_config
| | |
| | |--88.53%-- ieee80211_scan_work
| | | worker_thread
| | | kthread
| | | child_rip
| | --11.47%-- [...]
| --13.63%-- [...]
--1.78%-- [...]
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1249690585-9145-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If we recorded with -g option to record the callchain, right now
we require a -g option to perf report as well - and people reported
this as unnecessary complication: the user already specified -g
once, no need to require it a second time.
So if the recording includes call-chains, display the callchain by
default from perf report.
( The user can override this default using "-g none" option from
perf report. )
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1249690585-9145-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When the callchain tree comes to insert an empty backtrace, it
raises a spurious warning about the fact we are inserting an
empty. This is spurious because the radix tree assumes it did
something wrong to reach this state. But it didn't, we just met
an empty callchain that has to be ignored.
This happens occasionally with certain types of call-chain
recordings. If it happens it's a big nuisance as perf report
output starts with thousands of warning lines.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1249690585-9145-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
1. Ignore the -A argument if there is no perf.data file
2. Treat an empty file like a non existent file.
Else, perf will try to read the perf.data header, and fail with
an error.
Treating an empty file like a non-existent file makes sense,
since an interupted (as in SIGKILLed) perf could leave such
files around, and you don't want to annoy the user with errors
for files with no data in it.
Signed-off-by: Pierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While toying with perf, I've noticed that perf record can
easily enter a busy loop when doing something as silly as:
$ perf record -A ls
Yeah, do_read here really wants to read a known size, not being
able to should die(), not busy-loop ;)
That was the cause for the bug.
Signed-off-by: Pierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stop perf list from displaying tracepoints without an id file,
those are special tracepoints that are not interfaced to
perfcounters so listing them is erroneous and passing them as
events will produce no output.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If we have the powerpc perf_counter backend compiled in, but
the cpu we are running on is one where we don't support the
PMU, we currently oops in hw_perf_group_sched_in if we try to
use any counters, because ppmu is NULL in that case, and we
unconditionally dereference ppmu.
This fixes the problem by adding a check if ppmu is NULL at the
beginning of hw_perf_group_sched_in, and also at the beginning
of the other functions that get called from the perf_counter
core, i.e. hw_perf_disable, hw_perf_enable, and
hw_perf_counter_setup.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: benh@kernel.crashing.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Linus Torvalds