We are going to add libdw library support to do dwarf post unwind.
Making the code ready by moving libunwind dwarf post unwind stuff into
separate object.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-10-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding mask info into struct regs_dump to make the registers information
compact.
The mask was always passed along, so logically the mask info fits more
into the struct regs_dump.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-9-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We are not interested in zero addresses in callchain, do not report
them.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-8-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'unwind__get_entries' function currently returns 'max_stack + 1'
entries (instead of exact max_stack entries), because max_stack value
does not get decremented for the first entry.
This fix makes dwarf-unwind test pass.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-7-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding dwarf unwind test, that setups live machine data over the perf
test thread and does the remote unwind.
At this moment this test fails due to bug in the max_stack processing in
unwind__get_entries function. This is fixed in following patch.
Need to use -fno-optimize-sibling-calls for test compilation, otherwise
'krava_*' function calls are optimized into jumps and ommited from the
stack unwind.
So far it's enabled only for x86.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-6-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introducing perf_regs_load function, which is going to be used for dwarf
unwind test in following patches.
It takes single argument as a pointer to the regs dump buffer and
populates it with current registers values.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-5-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding people readable output for callchain debug, to get following '-v'
output:
$ perf record -v -g ls
callchain: type DWARF
callchain: stack dump size 4096
...
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1391427883-13443-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding call-graph option support into .perfconfig file, so it's now
possible use call-graph option like:
[top]
call-graph = fp
[record]
call-graph = dwarf,8192
Above options ONLY setup the unwind method. To enable perf record/top to
actually use it the command line option -g/-G must be specified.
The --call-graph option overloads .perfconfig setup.
Assuming above configuration:
$ perf record -g ls
- enables dwarf unwind with user stack size dump 8192 bytes
$ perf top -G
- enables frame pointer unwind
$ perf record --call-graph=fp ls
- enables frame pointer unwind
$ perf top --call-graph=dwarf,4096 ls
- enables dwarf unwind with user stack size dump 4096 bytes
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1391427883-13443-2-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We use PERF_SAMPLE_PERIOD sample type only for frequency
setup -F (default) option. The -c does not need store period,
because it's always the same.
In -c case the report code uses '1' as period. Fixing
it to perf_event_attr::sample_period.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1391427883-13443-1-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since all it wants is to get the 'struct record' from the received
'struct perf_tool', and this is already done at the callers of these
functions, short circuit it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-xz8p659sjpad396vye5t24gx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since two of the parameters come from the same 'struct
addr_location', rename machine__resolve_bstack() to sample__resolve_bstack()
and pass the that addr_location instead.
This is also for consistency with the same change that resulted in the
sample__resolve_mem() function.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-99ecqt8jiyyksiyx3se7l5ia@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since three of the parameters come from the same 'struct addr_location',
rename machine__resolve_mem() to sample__resolve_mem() and pass the
that addr_location instead.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-3f5otpssefh9l5hi1t259h8n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We don't need to recalculate cpumode from the perf_event->header field,
as this is already available in the struct addr_location->cpumode field.
Remove the function signature of functions that receive both perf_event
and addr_location parameters but use perf_event just to extract the
cpumode.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-tmct07y7mka54allj82trlnx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Supporting decoding the ioctl 'request' parameter needs more work to
properly support more architectures, the current approach doesn't work
on at least powerpc and sparc, as reported by Ben Hutchings in
http://lkml.kernel.org/r/1391593985.3003.48.camel@deadeye.wl.decadent.org.uk .
Work around that by making it to be ifdefed for the architectures known
to work with the current, limited approach, i386 and x86_64 till better
code is written.
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: <stable@vger.kernel.org> # 3.13 Fixes: 78645cf3ed ("perf trace: Initial beautifier for ioctl's 'cmd' arg")
Link: http://lkml.kernel.org/n/tip-ss04k11insqlu329xh5g02q0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
glibc 2.17 is missing this on sparc, despite the fact that it's not
architecture-specific.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 49af9e93ad ('perf trace: Beautify eventfd2 'flags' arg')
Cc: <stable@vger.kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1391648435.3003.100.camel@deadeye.wl.decadent.org.uk
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
"perf list" listing of hardware events doesn't work on older ARM devices.
The change enabling event detection:
commit b41f1cec91
Author: Namhyung Kim <namhyung.kim@lge.com>
Date: Tue Aug 27 11:41:53 2013 +0900
perf list: Skip unsupported events
uses the following code in tools/perf/util/parse-events.c:
struct perf_event_attr attr = {
.type = type,
.config = config,
.disabled = 1,
.exclude_kernel = 1,
};
On ARM machines pre-dating the Cortex-A15 this doesn't work, as these
machines don't support .exclude_kernel. So starting with 3.12 "perf
list" does not report any hardware events at all on older machines (seen
on Rasp-Pi, Pandaboard, Beagleboard, etc).
This version of the patch makes changes suggested by Namhyung Kim to
check for EACCESS and retry (instead of just dropping the
exclude_kernel) so we can properly handle machines where
/proc/sys/kernel/perf_event_paranoid is set to 2.
Reported-by: Chad Paradis <chad.paradis@umit.maine.edu>
Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Chad Paradis <chad.paradis@umit.maine.edu>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1312301536150.28814@vincent-weaver-1.um.maine.edu
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We removed event types from data file in following commits:
6065210 perf tools: Remove event types framework completely
44b3c57 perf tools: Remove event types from perf data file
We no longer need this information, because we can get it directly from
tracepoints.
But we still need to handle PERF_RECORD_HEADER_EVENT_TYPE event for the
sake of old perf data files created in pipe mode like:
$ perf.3.4 record -o - foo >perf.data
$ perf.312 report -i - < perf.data
Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1391524668-12546-1-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf-probe not to add offset value twice to uprobe probe address
when post processing.
The tevs[i].point.address struct member is the address of symbol+offset,
but current perf-probe adjusts the point.address by adding the offset.
As a result, the probe address becomes symbol+offset+offset. This may
cause unexpected code corruption. Urgent fix is needed.
Without this fix:
---
# ./perf probe -x ./perf dso__load_vmlinux+4
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d2b8)
# nm ./perf.orig | grep dso__load_vmlinux\$
000000000046d0a0 T dso__load_vmlinux
---
You can see the given offset is 3 but the actual probed address is
dso__load_vmlinux+8.
With this fix:
---
# ./perf probe -x ./perf dso__load_vmlinux+4
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d2b4)
---
Now the problem is fixed.
Note: This bug is introduced by
commit fb7345bbf7
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140205051858.6519.27314.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A bunch of unknown NMIs have popped up on a Pentium4 recently when booting
into a kdump kernel. This was exposed because the watchdog timer went
from 60 seconds down to 10 seconds (increasing the ability to reproduce
this problem).
What is happening is on boot up of the second kernel (the kdump one),
the previous nmi_watchdogs were enabled on thread 0 and thread 1. The
second kernel only initializes one cpu but the perf counter on thread 1
still counts.
Normally in a kdump scenario, the other cpus are blocking in an NMI loop,
but more importantly their local apics have the performance counters disabled
(iow LVTPC is masked). So any counters that fire are masked and never get
through to the second kernel.
However, on a P4 the local apic is shared by both threads and thread1's PMI
(despite being configured to only interrupt thread1) will generate an NMI on
thread0. Because thread0 knows nothing about this NMI, it is seen as an
unknown NMI.
This would be fine because it is a kdump kernel, strange things happen
what is the big deal about a single unknown NMI.
Unfortunately, the P4 comes with another quirk: clearing the overflow bit
to prevent a stream of NMIs. This is the problem.
The kdump kernel can not execute because of the endless NMIs that happen.
To solve this, I instrumented the p4 perf init code, to walk all the counters
and zero them out (just like a normal reset would).
Now when the counters go off, they do not generate anything and no unknown
NMIs are seen.
I tested this on a P4 we have in our lab. After two or three crashes, I could
normally reproduce the problem. Now after 10 crashes, everything continues
to boot correctly.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140120154115.GZ25953@redhat.com
[ Fixed a stylistic detail. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On a P4 box stressing perf with:
./perf record -o perf.data ./perf stat -v ./perf bench all
it was noticed that a slew of unknown NMIs would pop out rather quickly.
Painfully debugging this ancient platform, led me to notice cross cpu counter
corruption.
The P4 machine is special in that it has 18 counters, half are used for cpu0
and the other half is for cpu1 (or all 18 if hyperthreading is disabled). But
the splitting of the counters has to be actively managed by the software.
In this particular bug, one of the cpu0 specific counters was being used by
cpu1 and caused all sorts of random unknown nmis.
I am not entirely sure on the corruption path, but what happens is:
o perf schedules a group with p4_pmu_schedule_events()
o inside p4_pmu_schedule_events(), it notices an hwc pointer is being reused
but for a different cpu, so it 'swaps' the config bits and returns the
updated 'assign' array with a _new_ index.
o perf schedules another group with p4_pmu_schedule_events()
o inside p4_pmu_schedule_events(), it notices an hwc pointer is being reused
(the same one as above) but for the _same_ cpu [BUG!!], so it updates the
'assign' array to use the _old_ (wrong cpu) index because the _new_ index is in
an earlier part of the 'assign' array (and hasn't been committed yet).
o perf commits the transaction using the wrong index and corrupts the other cpu
The [BUG!!] is because the 'hwc->config' is updated but not the 'hwc->idx'. So
the check for 'p4_should_swap_ts()' is correct the first time around but
incorrect the second time around (because hwc->config was updated in between).
I think the spirit of perf was to not modify anything until all the
transactions had a chance to 'test' if they would succeed, and if so, commit
atomically. However, P4 breaks this spirit by touching the hwc->config
element.
So my fix is to continue the un-perf like breakage, by assigning hwc->idx to -1
on swap to tell follow up group scheduling to find a new index.
Of course if the transaction fails rolling this back will be difficult, but
that is not different than how the current code works. :-) And I wasn't sure
how much effort to cleanup the code I should do for a platform that is almost
10 years old by now.
Hence the lazy fix.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1391024270-19469-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Calling printk() from NMI context is bad (TM), so move it to IRQ
context.
In doing so we slightly change (probably wreck) the debugfs
nmi_longest_ns thingy, in that it doesn't update to reflect the
longest, nor does writing to it reset the count.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-rdw0au56a5ymis1u8p48c12d@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Calling printk() from NMI context is bad (TM), so move it to IRQ
context.
This also avoids the problem where the printk() time is measured by
the generic NMI duration goo and triggers a second warning.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-75dv35xf6dhhmeb7nq6fua31@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current code forgets to change the CR4 state on the current CPU.
Use on_each_cpu() instead of smp_call_function().
Reported-by: Mark Davies <junk@eslaf.co.uk>
Suggested-by: Mark Davies <junk@eslaf.co.uk>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
Link: http://lkml.kernel.org/n/tip-69efsat90ibhnd577zy3z9gh@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Protect pinctrl_list_add() with the proper mutex. This
was identified by RedHat. Caused nasty locking warnings
was rootcased by Stanislaw Gruszka.
- Avoid adding dangerous debugfs files when either half of
the subsystem is unused: pinmux or pinconf.
- Various fixes to various drivers: locking, hardware
particulars, DT parsing, error codes.
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Merge tag 'pinctrl-v3.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pinctrl fixes from Linus Walleij:
"First round of pin control fixes for v3.14:
- Protect pinctrl_list_add() with the proper mutex. This was
identified by RedHat. Caused nasty locking warnings was rootcased
by Stanislaw Gruszka.
- Avoid adding dangerous debugfs files when either half of the
subsystem is unused: pinmux or pinconf.
- Various fixes to various drivers: locking, hardware particulars, DT
parsing, error codes"
* tag 'pinctrl-v3.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: tegra: return correct error type
pinctrl: do not init debugfs entries for unimplemented functionalities
pinctrl: protect pinctrl_list add
pinctrl: sirf: correct the pin index of ac97_pins group
pinctrl: imx27: fix offset calculation in imx_read_2bit
pinctrl: vt8500: Change devicetree data parsing
pinctrl: imx27: fix wrong offset to ICONFB
pinctrl: at91: use locked variant of irq_set_handler
Pull x86 fixes from Peter Anvin:
"Quite a varied little collection of fixes. Most of them are
relatively small or isolated; the biggest one is Mel Gorman's fixes
for TLB range flushing.
A couple of AMD-related fixes (including not crashing when given an
invalid microcode image) and fix a crash when compiled with gcov"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, microcode, AMD: Unify valid container checks
x86, hweight: Fix BUG when booting with CONFIG_GCOV_PROFILE_ALL=y
x86/efi: Allow mapping BGRT on x86-32
x86: Fix the initialization of physnode_map
x86, cpu hotplug: Fix stack frame warning in check_irq_vectors_for_cpu_disable()
x86/intel/mid: Fix X86_INTEL_MID dependencies
arch/x86/mm/srat: Skip NUMA_NO_NODE while parsing SLIT
mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridge
x86: mm: change tlb_flushall_shift for IvyBridge
x86/mm: Eliminate redundant page table walk during TLB range flushing
x86/mm: Clean up inconsistencies when flushing TLB ranges
mm, x86: Account for TLB flushes only when debugging
x86/AMD/NB: Fix amd_set_subcaches() parameter type
x86/quirks: Add workaround for AMD F16h Erratum792
x86, doc, kconfig: Fix dud URL for Microcode data
I missed a couple errors in reviewing the patches converting jfs
to use the generic posix ACL function. Setting ACL's currently
fails with -EOPNOTSUPP.
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
On archs like S390 or um this driver cannot build nor work.
Make it depend on HAS_IOMEM to bypass build failures.
drivers/built-in.o: In function `dw_wdt_drv_probe':
drivers/watchdog/dw_wdt.c:302: undefined reference to `devm_ioremap_resource'
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Here is a single kernfs fix to resolve a much-reported lockdep issue with the
removal of entries in sysfs.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fix from Greg KH:
"Here is a single kernfs fix to resolve a much-reported lockdep issue
with the removal of entries in sysfs"
* tag 'driver-core-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag
Pull ceph fixes from Sage Weil:
"There is an RBD fix for a crash due to the immutable bio changes, an
error path fix, and a locking fix in the recent redirect support"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: do not dereference a NULL bio pointer
libceph: take map_sem for read in handle_reply()
libceph: factor out logic from ceph_osdc_start_request()
libceph: fix error handling in ceph_osdc_init()
does not conflict with the dynamic linker's one (64K)
- VDSO gettimeofday fix
- Barrier fixes for atomic operations and cache flushing
- TLB invalidation when overriding early page mappings during boot
- Wired up new 32-bit arm (compat) syscalls
- LSM_MMAP_MIN_ADDR when COMPAT is enabled
- defconfig update
- Clean-up (comments, pgd_alloc).
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Relax VDSO alignment requirements so that the kernel-picked one (4K)
does not conflict with the dynamic linker's one (64K)
- VDSO gettimeofday fix
- Barrier fixes for atomic operations and cache flushing
- TLB invalidation when overriding early page mappings during boot
- Wired up new 32-bit arm (compat) syscalls
- LSM_MMAP_MIN_ADDR when COMPAT is enabled
- defconfig update
- Clean-up (comments, pgd_alloc).
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: defconfig: Expand default enabled features
arm64: asm: remove redundant "cc" clobbers
arm64: atomics: fix use of acquire + release for full barrier semantics
arm64: barriers: allow dsb macro to take option parameter
security: select correct default LSM_MMAP_MIN_ADDR on arm on arm64
arm64: compat: Wire up new AArch32 syscalls
arm64: vdso: update wtm fields for CLOCK_MONOTONIC_COARSE
arm64: vdso: fix coarse clock handling
arm64: simplify pgd_alloc
arm64: fix typo: s/SERRROR/SERROR/
arm64: Invalidate the TLB when replacing pmd entries during boot
arm64: Align CMA sizes to PAGE_SIZE
arm64: add DSB after icache flush in __flush_icache_all()
arm64: vdso: prevent ld from aligning PT_LOAD segments to 64k
Pull MIPS updates from Ralf Baechle:
"hree minor patches. All have sat in -next for a few days"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: fpu.h: Fix build when CONFIG_BUG is not set
MIPS: Wire up sched_setattr/sched_getattr syscalls
MIPS: Alchemy: Fix DB1100 GPIO registration
Pull media fixes from Mauro Carvalho Chehab:
"A series of small fixes. Mostly driver ones. There is one core
regression fix on a patch that was meant to fix some race issues on
vb2, but that actually caused more harm than good. So, we're just
reverting it for now"
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] adv7842: Composite free-run platfrom-data fix
[media] v4l2-dv-timings: fix GTF calculation
[media] hdpvr: Fix memory leak in debug
[media] af9035: add ID [2040:f900] Hauppauge WinTV-MiniStick 2
[media] mxl111sf: Fix compile when CONFIG_DVB_USB_MXL111SF is unset
[media] mxl111sf: Fix unintentional garbage stack read
[media] cx24117: use a valid dev pointer for dev_err printout
[media] cx24117: remove dead code in always 'false' if statement
[media] update Michael Krufky's email address
[media] vb2: Check if there are buffers before streamon
[media] Revert "[media] videobuf_vm_{open,close} race fixes"
[media] go7007-loader: fix usb_dev leak
[media] media: bt8xx: add missing put_device call
[media] exynos4-is: Compile in fimc-lite runtime PM callbacks conditionally
[media] exynos4-is: Compile in fimc runtime PM callbacks conditionally
[media] exynos4-is: Fix error paths in probe() for !pm_runtime_enabled()
[media] s5p-jpeg: Fix wrong NV12 format parameters
[media] s5k5baf: allow to handle arbitrary long i2c sequences
Fix da9055 interrupt initialization
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Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon fixes from Guenter Roeck:
"Fix PMBus driver problem with some multi-page voltage sensors and fix
da9055 interrupt initialization"
* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (da9055) Remove use of regmap_irq_get_virq()
hwmon: (pmbus) Support per-page exponent in linear mode
- Fix for a recent ACPI hotplug regression causing a NULL pointer
dereference to occur while handling ACPI eject notifications for
already ejected devices. From Toshi Kani.
- Four concurrency-related fixes for ACPIPHP. Two of them add
missing locking and the other two fix race conditions related to
reference counting.
- ACPIPHP fix to avoid NULL pointer dereferences during device removal
involving Virtual Funcions.
- intel_pstate fix to make it compute the percentage of time the CPU
is busy properly. From Dirk Brandewie.
- Removal of two unnecessary NULL pointer checks in ACPI code and a
fix for sscanf() format string from Dan Carpenter and Luis G.F.
- New ACPI video blacklist entry for HP EliteBook Revolve 810 from
Mika Westerberg.
/
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Merge tag 'pm+acpi-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management fixes from Rafael Wysocki:
"These include a fix for a recent ACPI hotplug regression, four
concurrency related fixes and one PCI device removal fix for
ACPI-based PCI hotplug (ACPIPHP), intel_pstate fix that should go into
stable, three simple ACPI cleanups and a new entry for the ACPI video
blacklist.
Specifics:
- Fix for a recent ACPI hotplug regression causing a NULL pointer
dereference to occur while handling ACPI eject notifications for
already ejected devices. From Toshi Kani.
- Four concurrency-related fixes for ACPIPHP. Two of them add
missing locking and the other two fix race conditions related to
reference counting.
- ACPIPHP fix to avoid NULL pointer dereferences during device
removal involving Virtual Funcions.
- intel_pstate fix to make it compute the percentage of time the CPU
is busy properly. From Dirk Brandewie.
- Removal of two unnecessary NULL pointer checks in ACPI code and a
fix for sscanf() format string from Dan Carpenter and Luis G.F.
- New ACPI video blacklist entry for HP EliteBook Revolve 810 from
Mika Westerberg"
* tag 'pm+acpi-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / hotplug: Fix panic on eject to ejected device
ACPI / battery: Fix incorrect sscanf() string in acpi_battery_init_alarm()
ACPI / proc: remove unneeded NULL check
ACPI / utils: remove a pointless NULL check
ACPI / video: Add HP EliteBook Revolve 810 to the blacklist
intel_pstate: Take core C0 time into account for core busy calculation
ACPI / hotplug / PCI: Fix bridge removal race vs dock events
ACPI / hotplug / PCI: Fix bridge removal race in handle_hotplug_event()
ACPI / hotplug / PCI: Scan root bus under the PCI rescan-remove lock
ACPI / hotplug / PCI: Move PCI rescan-remove locking to hotplug_event()
ACPI / hotplug / PCI: Remove entries from bus->devices in reverse order
Commit f38a5181d9 ("ceph: Convert to immutable biovecs") introduced
a NULL pointer dereference, which broke rbd in -rc1. Fix it.
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Handling redirect replies requires both map_sem and request_mutex.
Taking map_sem unconditionally near the top of handle_reply() avoids
possible race conditions that arise from releasing request_mutex to be
able to acquire map_sem in redirect reply case. (Lock ordering is:
map_sem, request_mutex, crush_mutex.)
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Factor out logic from ceph_osdc_start_request() into a new helper,
__ceph_osdc_start_request(). ceph_osdc_start_request() now amounts to
taking locks and calling __ceph_osdc_start_request().
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
FPGA implementations of the Cortex-A57 and Cortex-A53 are now available
in the form of the SMM-A57 and SMM-A53 Soft Macrocell Models (SMMs) for
Versatile Express. As these attach to a Motherboard Express V2M-P1 it
would be useful to have support for some V2M-P1 peripherals enabled by
default.
Additionally a couple of of features have been introduced since the last
defconfig update (CMA, jump labels) that would be good to have enabled
by default to ensure they are build and boot tested.
This patch updates the arm64 defconfig to enable support for these
devices and features. The arm64 Kconfig is modified to select
HAVE_PATA_PLATFORM, which is required to enable support for the
CompactFlash controller on the V2M-P1.
A few options which don't need to appear in defconfig are trimmed:
* BLK_DEV - selected by default
* EXPERIMENTAL - otherwise gone from the kernel
* MII - selected by drivers which require it
* USB_SUPPORT - selected by default
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
cbnz/tbnz don't update the condition flags, so remove the "cc" clobbers
from inline asm blocks that only use these instructions to implement
conditional branches.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Linux requires a number of atomic operations to provide full barrier
semantics, that is no memory accesses after the operation can be
observed before any accesses up to and including the operation in
program order.
On arm64, these operations have been incorrectly implemented as follows:
// A, B, C are independent memory locations
<Access [A]>
// atomic_op (B)
1: ldaxr x0, [B] // Exclusive load with acquire
<op(B)>
stlxr w1, x0, [B] // Exclusive store with release
cbnz w1, 1b
<Access [C]>
The assumption here being that two half barriers are equivalent to a
full barrier, so the only permitted ordering would be A -> B -> C
(where B is the atomic operation involving both a load and a store).
Unfortunately, this is not the case by the letter of the architecture
and, in fact, the accesses to A and C are permitted to pass their
nearest half barrier resulting in orderings such as Bl -> A -> C -> Bs
or Bl -> C -> A -> Bs (where Bl is the load-acquire on B and Bs is the
store-release on B). This is a clear violation of the full barrier
requirement.
The simple way to fix this is to implement the same algorithm as ARMv7
using explicit barriers:
<Access [A]>
// atomic_op (B)
dmb ish // Full barrier
1: ldxr x0, [B] // Exclusive load
<op(B)>
stxr w1, x0, [B] // Exclusive store
cbnz w1, 1b
dmb ish // Full barrier
<Access [C]>
but this has the undesirable effect of introducing *two* full barrier
instructions. A better approach is actually the following, non-intuitive
sequence:
<Access [A]>
// atomic_op (B)
1: ldxr x0, [B] // Exclusive load
<op(B)>
stlxr w1, x0, [B] // Exclusive store with release
cbnz w1, 1b
dmb ish // Full barrier
<Access [C]>
The simple observations here are:
- The dmb ensures that no subsequent accesses (e.g. the access to C)
can enter or pass the atomic sequence.
- The dmb also ensures that no prior accesses (e.g. the access to A)
can pass the atomic sequence.
- Therefore, no prior access can pass a subsequent access, or
vice-versa (i.e. A is strictly ordered before C).
- The stlxr ensures that no prior access can pass the store component
of the atomic operation.
The only tricky part remaining is the ordering between the ldxr and the
access to A, since the absence of the first dmb means that we're now
permitting re-ordering between the ldxr and any prior accesses.
From an (arbitrary) observer's point of view, there are two scenarios:
1. We have observed the ldxr. This means that if we perform a store to
[B], the ldxr will still return older data. If we can observe the
ldxr, then we can potentially observe the permitted re-ordering
with the access to A, which is clearly an issue when compared to
the dmb variant of the code. Thankfully, the exclusive monitor will
save us here since it will be cleared as a result of the store and
the ldxr will retry. Notice that any use of a later memory
observation to imply observation of the ldxr will also imply
observation of the access to A, since the stlxr/dmb ensure strict
ordering.
2. We have not observed the ldxr. This means we can perform a store
and influence the later ldxr. However, that doesn't actually tell
us anything about the access to [A], so we've not lost anything
here either when compared to the dmb variant.
This patch implements this solution for our barriered atomic operations,
ensuring that we satisfy the full barrier requirements where they are
needed.
Cc: <stable@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Remove use of regmap_irq_get_virq() in driver probe which was
conflicting with use of platform_get_irq_byname().
platform_get_irq_byname() already returns the VIRQ number due
to MFD core translation so using regmap_irq_get_virq() on that
returned value results in an incorrect IRQ being requested.
The driver probes then fail because of this.
Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Jiri Olsa