LLC-* and node-* events require using the OFFCORE_RESPONSE events
on SandyBridge, but the hw_cache_extra_regs is left uninitialized.
This patch adds the missing extra register configure table for
SandyBridge.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342517275-2875-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The uncore subsystem in Nehalem-EX consists of 7 components
(U-Box, C-Box, B-Box, S-Box, R-Box, M-Box and W-Box). This
patch is large because the way to program these boxes is
diverse.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4FF534F1.3030307@intel.com
[ Improved the code. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The format definition of uncore PCU filter should be filter_band*
instead of filter_brand*.
Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1343024611-4692-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Otherwise they can't be filtered for a defined task:
perf record -e sched:sched_switch ./foo
This command doesn't report any events without this patch.
I think it isn't a security concern if someone knows who will
be executed next - this can already be observed by polling /proc
state. By default perf is disabled for non-root users in any case.
I need these events for profiling sleep times. sched_switch is used for
getting callchains and sched_stat_* is used for getting time periods.
These events are combined in user space, then it can be analyzed by
perf tools.
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arun Sharma <asharma@fb.com>
Link: http://lkml.kernel.org/r/1342088069-1005148-1-git-send-email-avagin@openvz.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
. libtraceevent build fixes from Namhyung Kim
. Prevent overflow when calculating annotation buckets size, from Cody Schafer
. Set breakpoint events sample period to 1, just like trace events, from Jovi Zhang
. Fix strerror_r usage, from Kirill Shutemov
. Fix duplicate function declaration problems with bison 2.6, from Kirill Shutemov
. Add DSO caching facility (and perf test entry) to speed up binary file
reading, will be used by the DWARF unwind code, from Jiri Olsa
. Fix trace event storms by setting PERF_SAMPLE_PERIOD, from Frederic Weisbecker
. perf kvm fixes from David Ahern
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo:
* libtraceevent build fixes from Namhyung Kim
* Prevent overflow when calculating annotation buckets size, from Cody Schafer
* Set breakpoint events sample period to 1, just like trace events, from Jovi Zhang
* Fix strerror_r usage, from Kirill Shutemov
* Fix duplicate function declaration problems with bison 2.6, from Kirill Shutemov
* Add DSO caching facility (and perf test entry) to speed up binary file
reading, will be used by the DWARF unwind code, from Jiri Olsa
* Fix trace event storms by setting PERF_SAMPLE_PERIOD, from Frederic Weisbecker
* perf kvm fixes from David Ahern
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A large enough symbol size causes an overflow in the size parameter to
the histogram allocation, leading to a segfault in
symbol__inc_addr_samples later on when this histogram is accessed.
In the case of being called via perf-report, this returns back and
gracefully ignores the sample, eventually ignoring the chained return
value of perf_session_deliver_event in flush_sample_queue.
Signed-off-by: Cody Schafer <cody@linux.vnet.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1342753525-4521-1-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The TRACEEVENT-CFLAGS file is used to detect any change on compiler
flags. Just ignore it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1341559297-25725-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cross compiling perf requires setting ARCH and CROSS_COMPILE variables,
but libtraceevent couldn't detect the changes so it ends up believing no
recompiling is required. Thus the linker failed like:
LINK perf
../lib/traceevent//libtraceevent.a: member ../lib/traceevent//libtraceevent.a(event-parse.o) in archive is not an object
collect2: ld returned 1 exit status
make: *** [perf] Error 1
This patch fixes this by adding TRACEEVENT-CFLAGS file like
PERF-CFLAGS to track those changes.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1341559297-25725-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Bison 2.6 started to generate parse_events_parse() declaration in header. In
this case we have redundant redeclaration:
util/parse-events.c:29:5: error: redundant redeclaration of ‘parse_events_parse’ [-Werror=redundant-decls]
In file included from util/parse-events.c:14:0:
util/parse-events-bison.h:99:5: note: previous declaration of ‘parse_events_parse’ was here
cc1: all warnings being treated as errors
Let's disable -Wredundant-decls for util/parse-events.c since it includes
header we can't control.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
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/20120723210407.GA25186@shutemov.name
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf uses GNU-specific version of strerror_r(). The GNU-specific strerror_r()
returns a pointer to a string containing the error message. This may be either
a pointer to a string that the function stores in buf, or a pointer to some
(immutable) static string (in which case buf is unused).
In glibc-2.16 GNU version was marked with attribute warn_unused_result. It
triggers few warnings in perf:
util/target.c: In function ‘perf_target__strerror’:
util/target.c:114:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]
ui/browsers/hists.c: In function ‘hist_browser__dump’:
ui/browsers/hists.c:981:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]
They are bugs.
Let's fix strerror_r() usage.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Ulrich Drepper <drepper@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/20120723210654.GA25248@shutemov.name
[ committer note: s/assert/BUG_ON/g ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There have one problem about hw_breakpoint perf event, as watched, the
events reported to userspace is not correctly, sometime one trigger
bp_event report several events, sometime bp_event cannot go through to
user.
The root cause is attr->freq is 1 passed to kernel defaultly in bp
events, this make kernel calculate event period not as expect, make
sample period to 1 will change attr->freq to 0, to fix this problem.
This patch is similar with commit f92128 about tracepoint events:
perf: Make the trace events sample period default to 1
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CACV3sbLF8taiCq_VYW-sgRJyupeMzg58C7ZXfMe3xZUiH_Mx6w@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding dso data caching so we don't need to open/read/close, each time
we want dso data.
The DSO data caching affects following functions:
dso__data_read_offset
dso__data_read_addr
Each DSO read tries to find the data (based on offset) inside the cache.
If it's not present it fills the cache from file, and returns the data.
If it is present, data are returned with no file read.
Each data read is cached by reading cache page sized/aligned amount of
DSO data. The cache page size is hardcoded to 4096. The cache is using
RB tree with file offset as a sort key.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-17-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding following interface for DSO object to allow
reading of DSO image data:
dso__data_fd
- opens DSO and returns file descriptor
Binary types are used to locate/open DSO in following order:
DSO_BINARY_TYPE__BUILD_ID_CACHE
DSO_BINARY_TYPE__SYSTEM_PATH_DSO
In other word we first try to open DSO build-id path,
and if that fails we try to open DSO system path.
dso__data_read_offset
- reads DSO data from specified offset
dso__data_read_addr
- reads DSO data from specified address/map.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-11-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding interface to access DSOs so it could be used
from another place.
New DSO binary type is added - making current SYMTAB__*
types more general:
DSO_BINARY_TYPE__* = SYMTAB__*
Following function is added to return path based on the specified
binary type:
dso__binary_type_file
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-10-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Trace events have a period (weight) of 1 by default. This can be
overriden on events definition by using the __perf_count() macro.
For example, the sched_stat_runtime() is weighted with the runtime of
the task that fired the event.
By default, perf handles such weighted event by dividing it into
individual events carrying a weight of 1. For example if
sched_stat_runtime is fired and the task has run 5000000 nsecs, perf
divides it into 5000000 events in the buffer.
This behaviour makes weighted events unusable because they quickly
fullfill the buffers and we lose most events.
The commit 5d81e5cfb3 ("events: Don't
divide events if it has field period") solves this problem by sending
only one event when PERF_SAMPLE_PERIOD flag is set. The weight is
carried in the sample itself such that we don't need to demultiplex it
anymore.
This patch provides the last missing piece to use this feature by
setting PERF_SAMPLE_PERIOD from perf tools when we deal with trace
events.
Before:
$ ./perf record -e sched:* -a sleep 1
[ perf record: Woken up 3 times to write data ]
[ perf record: Captured and wrote 1.619 MB perf.data (~70749 samples) ]
Warning:
Processed 16909 events and lost 1 chunks!
Check IO/CPU overload!
$ ./perf script
perf 1894 [003] 824.898327: sched_migrate_task: comm=perf pid=1898 prio=120 orig_cpu=2 dest_cpu=0
perf 1894 [003] 824.898335: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898336: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898337: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898338: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898339: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898340: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898341: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
[...]
After:
$ ./perf record -e sched:* -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.074 MB perf.data (~3228 samples) ]
$ ./perf script
perf 1461 [000] 554.286957: sched_migrate_task: comm=perf pid=1465 prio=120 orig_cpu=3 dest_cpu=1
perf 1461 [000] 554.286964: sched_stat_sleep: comm=perf pid=1465 delay=133047190 [ns]
perf 1461 [000] 554.286967: sched_wakeup: comm=perf pid=1465 prio=120 success=1 target_cpu=001
swapper 0 [001] 554.286976: sched_stat_wait: comm=perf pid=1465 delay=0 [ns]
swapper 0 [001] 554.286983: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=perf
[...]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Include the omitted number of characters printed for the first entry.
Not that it really matters because nobody seem to care about the number
of printed characters for now. But just in case.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
After 7ed97ad use of the guestmount option without a subdir for *each*
VM generates an error message for each sample related to that VM. Once
per VM is enough.
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-7-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Guest kernel symbols are not resolved despite passing the information
needed to resolve them. e.g.,
perf kvm --guest --guestmount=/tmp/guest-mount record -a -- sleep 1
perf kvm --guest --guestmount=/tmp/guest-mount report --stdio
36.55% [guest/11399] [unknown] [g] 0xffffffff81600bc8
33.19% [guest/10474] [unknown] [g] 0x00000000c0116e00
30.26% [guest/11094] [unknown] [g] 0xffffffff8100a288
43.69% [guest/10474] [unknown] [g] 0x00000000c0103d90
37.38% [guest/11399] [unknown] [g] 0xffffffff81600bc8
12.24% [guest/11094] [unknown] [g] 0xffffffff810aa91d
6.69% [guest/11094] [unknown] [u] 0x00007fa784d721c3
which is just pathetic.
After a maddening 2 days sifting through perf minutia I found it --
id_hdr_size is not initialized for guest machines. This shows up on the
report side as random garbage for the cpu and timestamp, e.g.,
29816 7310572949125804849 0x1ac0 [0x50]: PERF_RECORD_MMAP ...
That messes up the sample sorting such that synthesized guest maps are
processed last.
With this patch you get a much more helpful report:
12.11% [guest/11399] [guest.kernel.kallsyms.11399] [g] irqtime_account_process_tick
10.58% [guest/11399] [guest.kernel.kallsyms.11399] [g] run_timer_softirq
6.95% [guest/11094] [guest.kernel.kallsyms.11094] [g] printk_needs_cpu
6.50% [guest/11094] [guest.kernel.kallsyms.11094] [g] do_timer
6.45% [guest/11399] [guest.kernel.kallsyms.11399] [g] idle_balance
4.90% [guest/11094] [guest.kernel.kallsyms.11094] [g] native_read_tsc
...
v2:
- changed rbtree walk to use rb_first per Namhyung's suggestion
Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
COMM events are not generated in the context of a guest machine, so the
thread name is never set for the VMM process. For example, the qemu-kvm
name applies to the process in the host machine, not the guest machine.
So, samples for guest machines are currently displayed as:
99.67% :5671 [unknown] [g] 0xffffffff81366b41
where 5671 is the pid of the VMM. With this patch the samples in the guest
machine are shown as:
18.43% [guest/5671] [unknown] [g] 0xffffffff810d68b7
Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Current debug message is:
Problems creating module maps, continuing anyway...
When running multiple VMs it would be nice to know which machine the
message is referring to:
$ perf kvm --guest --guestmount=/tmp/guest-mount record -av -- sleep 10
Problems creating module maps for guest 6613, continuing anyway...
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-2-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull a x86/build change from Ingo Molnar.
This makes the default stack alignment on x86-64 be just 8, allowing for
improved code generation (it can avoid some unnecessary extra alignment
logic and use just pure push/pop sequences) and smaller stack frames.
We can't generally do SSE with 16-byte alignment issues in the kernel anyway.
* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86-64, gcc: Use -mpreferred-stack-boundary=3 if supported
Pull x86/uv changes from Ingo Molnar:
"UV2 BAU productization fixes.
The BAU (Broadcast Assist Unit) is SGI's fancy out of line way on UV
hardware to do TLB flushes, instead of the normal APIC IPI methods.
The commits here fix / work around hangs in their latest hardware
iteration (UV2).
My understanding is that the main purpose of the out of line
signalling channel is to improve scalability: the UV APIC hardware
glue does not handle broadcasting to many CPUs very well, and this
matters most for TLB shootdowns.
[ I don't agree with all aspects of the current approach: in hindsight
it would have been better to link the BAU at the IPI/APIC driver
level instead of the TLB shootdown level, where TLB flushes are
really just one of the uses of broadcast SMP messages. Doing that
would improve scalability in some other ways and it would also
remove a few uglies from the TLB path. It would also be nice to
push more is_uv_system() tests into proper x86_init or x86_platform
callbacks. Cliff? ]"
* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/uv: Work around UV2 BAU hangs
x86/uv: Implement UV BAU runtime enable and disable control via /proc/sgi_uv/
x86/uv: Fix the UV BAU destination timeout period
Pull x86/reboot changes from Ingo Molnar:
"Now that the revampted x86 real-mode trampoline code is upstream and
seems to be working well, we can extend the 64-bit reboot code to be
as capable as the 32-bit one."
* 'x86-reboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86-64, reboot: Be more paranoid in 64-bit reboot=bios
x86, reboot: Drop redundant write of reboot_mode
x86-64, reboot: Allow reboot=bios and reboot-cpu override on x86-64
Pull x86 platform changes from Ingo Molnar:
"This tree mostly involves various APIC driver cleanups/robustization,
and vSMP motivated platform callback improvements/cleanups"
Fix up trivial conflict due to printk cleanup right next to return value
change.
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
Revert "x86/early_printk: Replace obsolete simple_strtoul() usage with kstrtoint()"
x86/apic/x2apic: Use multiple cluster members for the irq destination only with the explicit affinity
x86/apic/x2apic: Limit the vector reservation to the user specified mask
x86/apic: Optimize cpu traversal in __assign_irq_vector() using domain membership
x86/vsmp: Fix vector_allocation_domain's return value
irq/apic: Use config_enabled(CONFIG_SMP) checks to clean up irq_set_affinity() for UP
x86/vsmp: Fix linker error when CONFIG_PROC_FS is not set
x86/apic/es7000: Make apicid of a cluster (not CPU) from a cpumask
x86/apic/es7000+summit: Always make valid apicid from a cpumask
x86/apic/es7000+summit: Fix compile warning in cpu_mask_to_apicid()
x86/apic: Fix ugly casting and branching in cpu_mask_to_apicid_and()
x86/apic: Eliminate cpu_mask_to_apicid() operation
x86/x2apic/cluster: Vector_allocation_domain() should return a value
x86/apic/irq_remap: Silence a bogus pr_err()
x86/vsmp: Ignore IOAPIC IRQ affinity if possible
x86/apic: Make cpu_mask_to_apicid() operations check cpu_online_mask
x86/apic: Make cpu_mask_to_apicid() operations return error code
x86/apic: Avoid useless scanning thru a cpumask in assign_irq_vector()
x86/apic: Try to spread IRQ vectors to different priority levels
x86/apic: Factor out default vector_allocation_domain() operation
...
Pull debug-for-linus git tree from Ingo Molnar.
Fix up trivial conflict in arch/x86/kernel/cpu/perf_event_intel.c due to
a printk() having changed to a pr_info() differently in the two branches.
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Move call to print_modules() out of show_regs()
x86/mm: Mark free_initrd_mem() as __init
x86/microcode: Mark microcode_id[] as __initconst
x86/nmi: Clean up register_nmi_handler() usage
x86: Save cr2 in NMI in case NMIs take a page fault (for i386)
x86: Remove cmpxchg from i386 NMI nesting code
x86: Save cr2 in NMI in case NMIs take a page fault
x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>
Pull x86/asm changes from Ingo Molnar:
"Assorted single-commit improvements, as usual"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/mtrr: Slightly simplify print_mtrr_state()
x86/mm/mtrr: Fix alignment determination in range_to_mtrr()
x86/copy_user_generic: Optimize copy_user_generic with CPU erms feature
x86/alternatives: Use atomic_xchg() instead atomic_dec_and_test() for stop_machine_text_poke()
Pull timer core changes from Ingo Molnar:
"Continued cleanups of the core time and NTP code, plus more nohz work
preparing for tick-less userspace execution."
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Rework timekeeping functions to take timekeeper ptr as argument
time: Move xtime_nsec adjustment underflow handling timekeeping_adjust
time: Move arch_gettimeoffset() usage into timekeeping_get_ns()
time: Refactor accumulation of nsecs to secs
time: Condense timekeeper.xtime into xtime_sec
time: Explicitly use u32 instead of int for shift values
time: Whitespace cleanups per Ingo%27s requests
nohz: Move next idle expiry time record into idle logic area
nohz: Move ts->idle_calls incrementation into strict idle logic
nohz: Rename ts->idle_tick to ts->last_tick
nohz: Make nohz API agnostic against idle ticks cputime accounting
nohz: Separate idle sleeping time accounting from nohz logic
timers: Improve get_next_timer_interrupt()
timers: Add accounting of non deferrable timers
timers: Consolidate base->next_timer update
timers: Create detach_if_pending() and use it
Pull perf events changes from Ingo Molnar:
"- kernel side:
- Intel uncore PMU support for Nehalem and Sandy Bridge CPUs, we
support both the events available via the MSR and via the PCI
access space.
- various uprobes cleanups and restructurings
- PMU driver quirks by microcode version and required x86 microcode
loader cleanups/robustization
- various tracing robustness updates
- static keys: remove obsolete static_branch()
- tooling side:
- GTK browser improvements
- perf report browser: support screenshots to file
- more automated tests
- perf kvm improvements
- perf bench refinements
- build environment improvements
- pipe mode improvements
- libtraceevent updates, we have now hopefully merged most bits with
the out of tree forked code base
... and many other goodies."
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (138 commits)
tracing: Check for allocation failure in __tracing_open()
perf/x86: Fix intel_perfmon_event_mapformatting
jump label: Remove static_branch()
tracepoint: Use static_key_false(), since static_branch() is deprecated
perf/x86: Uncore filter support for SandyBridge-EP
perf/x86: Detect number of instances of uncore CBox
perf/x86: Fix event constraint for SandyBridge-EP C-Box
perf/x86: Use 0xff as pseudo code for fixed uncore event
perf/x86: Save a few bytes in 'struct x86_pmu'
perf/x86: Add a microcode revision check for SNB-PEBS
perf/x86: Improve debug output in check_hw_exists()
perf/x86/amd: Unify AMD's generic and family 15h pmus
perf/x86: Move Intel specific code to intel_pmu_init()
perf/x86: Rename Intel specific macros
perf/x86: Fix USER/KERNEL tagging of samples
perf tools: Split event symbols arrays to hw and sw parts
perf tools: Split out PE_VALUE_SYM parsing token to SW and HW tokens
perf tools: Add empty rule for new line in event syntax parsing
perf test: Use ARRAY_SIZE in parse events tests
tools lib traceevent: Cleanup realloc use
...
Pull RCU changes from Ingo Molnar:
"Quoting from Paul, the major features of this series are:
1. Preventing latency spikes of more than 200 microseconds for
kernels built with NR_CPUS=4096, which is reportedly becoming the
default for some distros. This is a first step, as it does not
help with systems that actually -have- 4096 CPUs (work on this case
is in progress, but is not yet ready for mainline).
This category also includes improving concurrency of rcu_barrier(),
placed here due to conflicts. Posted to LKML at:
https://lkml.org/lkml/2012/6/22/381
Note that patches 18-22 of that series have been defered to 3.7, as
they have not yet proven themselves to be mainline-ready (and yes,
these are the ones intended to get rid of RCU's latency spikes for
systems that actually have 4096 CPUs).
2. Updates to documentation and rcutorture fixes, the latter category
including improvements to rcu_barrier() testing. Posted to LKML at
http://lkml.indiana.edu/hypermail/linux/kernel/1206.1/04094.html.
3. Miscellaneous fixes posted to LKML at:
https://lkml.org/lkml/2012/6/22/500
with the exception of the last commit, which was posted here:
http://www.gossamer-threads.com/lists/linux/kernel/1561830
4. RCU_FAST_NO_HZ fixes and improvements. Posted to LKML at:
http://lkml.indiana.edu/hypermail/linux/kernel/1206.1/00006.htmlhttp://www.gossamer-threads.com/lists/linux/kernel/1561833
The first four patches of the first series went into 3.5 to fix a
regression.
5. Code-style fixes. These were posted to LKML at
http://lkml.indiana.edu/hypermail/linux/kernel/1205.2/01180.htmlhttp://lkml.indiana.edu/hypermail/linux/kernel/1205.2/01181.html"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
rcu: Fix broken strings in RCU's source code.
rcu: Fix code-style issues involving "else"
rcu: Introduce check for callback list/count mismatch
rcu: Make RCU_FAST_NO_HZ respect nohz= boot parameter
rcu: Fix qlen_lazy breakage
rcu: Round FAST_NO_HZ lazy timeout to nearest second
rcu: The rcu_needs_cpu() function is not a quiescent state
rcu: Dump only the current CPU's buffers for idle-entry/exit warnings
rcu: Add check for CPUs going offline with callbacks queued
rcu: Disable preemption in rcu_blocking_is_gp()
rcu: Prevent uninitialized string in RCU CPU stall info
rcu: Fix rcu_is_cpu_idle() #ifdef in TINY_RCU
rcu: Split RCU core processing out of __call_rcu()
rcu: Prevent __call_rcu() from invoking RCU core on offline CPUs
rcu: Make __call_rcu() handle invocation from idle
rcu: Remove function versions of __kfree_rcu and __is_kfree_rcu_offset
rcu: Consolidate tree/tiny __rcu_read_{,un}lock() implementations
rcu: Remove return value from rcu_assign_pointer()
key: Remove extraneous parentheses from rcu_assign_keypointer()
rcu: Remove return value from RCU_INIT_POINTER()
...
Pull core/iommu changes from Ingo Molnar.
* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
iommu/dmar: Use pr_format() instead of PREFIX to tidy up pr_*() calls
iommu/dmar: Reserve mmio space used by the IOMMU, if the BIOS forgets to
iommu/dmar: Replace printks with appropriate pr_*()
This reverts commit fbd24153c4.
This commit is subtly buggy: kstrto*int() can return an error but
it's not checked in every path. simple_strtoul() on the other hand
could not fail, so this patch subtly intruduces new failure modes.
Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Link: http://lkml.kernel.org/r/1338424803.3569.5.camel@lorien2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The SYSTEM_SUSPEND_DISK system state is never used, so drop it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge emailed kgdb dmesg fixups patches from Anton Vorontsov:
"The dmesg command appears to be broken after the printk rework. The
old logic in the kdb code makes no sense in terms of current
printk/logging storage format, and KDB simply hangs forever upon
entering 'dmesg' command.
The first patch revives the command by switching to kmsg_dumper
iterator. As a side-effect, the code is now much more simpler.
A few changes were needed in the printk.c: we needed unlocked variant
of the kmsg_dumper iterator, but these can surely wait for 3.6.
It's probably too late even for the first patch to go to 3.5, but I'll
try to convince otherwise. :-) Here we go:
- The current code is broken for sure, and has no hope to work at
all. It is a regression
- The new code works for me, and probably works for everyone else;
- If it compiles (and I urge everyone to compile-test it on your
setup), it hardly can make things worse."
* Merge emailed patches from Anton Vorontsov: (4 commits)
kdb: Switch to nolock variants of kmsg_dump functions
printk: Implement some unlocked kmsg_dump functions
printk: Remove kdb_syslog_data
kdb: Revive dmesg command
The locked variants are prone to deadlocks (suppose we got to the
debugger w/ the logbuf lock held), so let's switch to nolock variants.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If used from KDB, the locked variants are prone to deadlocks (suppose we
got to the debugger w/ the logbuf lock held).
So, we have to implement a few routines that grab no logbuf lock.
Yet we don't need these functions in modules, so we don't export them.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The function is no longer needed, so remove it.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kgdb dmesg command is broken after the printk rework. The old logic
in kdb code makes no sense in terms of current printk/logging storage
format, and KDB simply hangs forever.
This patch revives the command by switching to kmsg_dumper iterator.
The code is now much more simpler and shorter.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull late MIPS fixes from Ralf Baechle:
"This fixes a number of lose ends in the MIPS code and various bug
fixes.
Aside of dropping some patch that should not be in this pull request
everything has sat in -next for quite a while and there are no known
issues.
The biggest patch in this patch set moves the allocation of an array
that is aliased to a function (for runtime generated code) to
assembler code. This avoids an issue with certain toolchains when
building for microMIPS."
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (35 commits)
MIPS: PCI: Move fixups from __init to __devinit.
MIPS: Fix bug.h MIPS build regression
MIPS: sync-r4k: remove redundant irq operation
MIPS: smp: Warn on too early irq enable
MIPS: call set_cpu_online() on cpu being brought up with irq disabled
MIPS: call ->smp_finish() a little late
MIPS: Yosemite: delay irq enable to ->smp_finish()
MIPS: SMTC: delay irq enable to ->smp_finish()
MIPS: BMIPS: delay irq enable to ->smp_finish()
MIPS: Octeon: delay enable irq to ->smp_finish()
MIPS: Oprofile: Fix build as a module.
MIPS: BCM63XX: Fix BCM6368 IPSec clock bit
MIPS: perf: Fix build error caused by unused counters_per_cpu_to_total()
MIPS: Fix Magic SysRq L kernel crash.
MIPS: BMIPS: Fix duplicate header inclusion.
mips: mark const init data with __initconst instead of __initdata
MIPS: cmpxchg.h: Add missing include
MIPS: Malta may also be equipped with MIPS64 R2 processors.
MIPS: Fix typo multipy -> multiply
MIPS: Cavium: Fix duplicate ARCH_SPARSEMEM_ENABLE in kconfig.
...
- avoid a crash in dm-raid1 when discards coincide with mirror recovery;
- avoid discarding shared data that's still needed in dm-thin;
- don't guarantee that discarded blocks will be wiped in dm-raid1.
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Merge tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull device-mapper discard fixes from Alasdair G Kergon:
- avoid a crash in dm-raid1 when discards coincide with mirror
recovery;
- avoid discarding shared data that's still needed in dm-thin;
- don't guarantee that discarded blocks will be wiped in dm-raid1.
* tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
dm raid1: set discard_zeroes_data_unsupported
dm thin: do not send discards to shared blocks
dm raid1: fix crash with mirror recovery and discard
Pull pnfs/ore fixes from Boaz Harrosh:
"These are catastrophic fixes to the pnfs objects-layout that were just
discovered. They are also destined for @stable.
I have found these and worked on them at around RC1 time but
unfortunately went to the hospital for kidney stones and had a very
slow recovery. I refrained from sending them as is, before proper
testing, and surly I have found a bug just yesterday.
So now they are all well tested, and have my sign-off. Other then
fixing the problem at hand, and assuming there are no bugs at the new
code, there is low risk to any surrounding code. And in anyway they
affect only these paths that are now broken. That is RAID5 in pnfs
objects-layout code. It does also affect exofs (which was not broken)
but I have tested exofs and it is lower priority then objects-layout
because no one is using exofs, but objects-layout has lots of users."
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
pnfs-obj: Fix __r4w_get_page when offset is beyond i_size
pnfs-obj: don't leak objio_state if ore_write/read fails
ore: Unlock r4w pages in exact reverse order of locking
ore: Remove support of partial IO request (NFS crash)
ore: Fix NFS crash by supporting any unaligned RAID IO
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the
fix. It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users.
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Merge tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs
Pull UBIFS free space fix-up bugfix from Artem Bityutskiy:
"It's been reported already twice recently:
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the fix.
It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users."
* tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs:
UBIFS: fix a bug in empty space fix-up
We can't guarantee that REQ_DISCARD on dm-mirror zeroes the data even if
the underlying disks support zero on discard. So this patch sets
ti->discard_zeroes_data_unsupported.
For example, if the mirror is in the process of resynchronizing, it may
happen that kcopyd reads a piece of data, then discard is sent on the
same area and then kcopyd writes the piece of data to another leg.
Consequently, the data is not zeroed.
The flag was made available by commit 983c7db347
(dm crypt: always disable discard_zeroes_data).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When process_discard receives a partial discard that doesn't cover a
full block, it sends this discard down to that block. Unfortunately, the
block can be shared and the discard would corrupt the other snapshots
sharing this block.
This patch detects block sharing and ends the discard with success when
sending it to the shared block.
The above change means that if the device supports discard it can't be
guaranteed that a discard request zeroes data. Therefore, we set
ti->discard_zeroes_data_unsupported.
Thin target discard support with this bug arrived in commit
104655fd4d (dm thin: support discards).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch fixes a crash when a discard request is sent during mirror
recovery.
Firstly, some background. Generally, the following sequence happens during
mirror synchronization:
- function do_recovery is called
- do_recovery calls dm_rh_recovery_prepare
- dm_rh_recovery_prepare uses a semaphore to limit the number
simultaneously recovered regions (by default the semaphore value is 1,
so only one region at a time is recovered)
- dm_rh_recovery_prepare calls __rh_recovery_prepare,
__rh_recovery_prepare asks the log driver for the next region to
recover. Then, it sets the region state to DM_RH_RECOVERING. If there
are no pending I/Os on this region, the region is added to
quiesced_regions list. If there are pending I/Os, the region is not
added to any list. It is added to the quiesced_regions list later (by
dm_rh_dec function) when all I/Os finish.
- when the region is on quiesced_regions list, there are no I/Os in
flight on this region. The region is popped from the list in
dm_rh_recovery_start function. Then, a kcopyd job is started in the
recover function.
- when the kcopyd job finishes, recovery_complete is called. It calls
dm_rh_recovery_end. dm_rh_recovery_end adds the region to
recovered_regions or failed_recovered_regions list (depending on
whether the copy operation was successful or not).
The above mechanism assumes that if the region is in DM_RH_RECOVERING
state, no new I/Os are started on this region. When I/O is started,
dm_rh_inc_pending is called, which increases reg->pending count. When
I/O is finished, dm_rh_dec is called. It decreases reg->pending count.
If the count is zero and the region was in DM_RH_RECOVERING state,
dm_rh_dec adds it to the quiesced_regions list.
Consequently, if we call dm_rh_inc_pending/dm_rh_dec while the region is
in DM_RH_RECOVERING state, it could be added to quiesced_regions list
multiple times or it could be added to this list when kcopyd is copying
data (it is assumed that the region is not on any list while kcopyd does
its jobs). This results in memory corruption and crash.
There already exist bypasses for REQ_FLUSH requests: REQ_FLUSH requests
do not belong to any region, so they are always added to the sync list
in do_writes. dm_rh_inc_pending does not increase count for REQ_FLUSH
requests. In mirror_end_io, dm_rh_dec is never called for REQ_FLUSH
requests. These bypasses avoid the crash possibility described above.
These bypasses were improperly implemented for REQ_DISCARD when
the mirror target gained discard support in commit
5fc2ffeabb (dm raid1: support discard).
In do_writes, REQ_DISCARD requests is always added to the sync queue and
immediately dispatched (even if the region is in DM_RH_RECOVERING). However,
dm_rh_inc and dm_rh_dec is called for REQ_DISCARD resusts. So it violates the
rule that no I/Os are started on DM_RH_RECOVERING regions, and causes the list
corruption described above.
This patch changes it so that REQ_DISCARD requests follow the same path
as REQ_FLUSH. This avoids the crash.
Reference: https://bugzilla.redhat.com/837607
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
