Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull v3.7 RCU commits from Paul E. McKenney:
"
0. A fix for a latent bug that has been in RCU ever since the
addition of CPU stall warnings. This bug results in
false-positive stall warnings, but thus far only on embedded
systems with severely cut-down userspace configurations.
This fix is located on an rcu/urgent branch, with the rest
of the commits based on top of it. This commit CCs stable.
Given that the merge window is coming quite soon and given
the small number of affected users, I do -not- recommend
pushing it to 3.6, but the separate branch makes it easy to
find if someone needs it.
1. Further reductions in latency spikes for huge systems, along
with additional boot-time adaptation to the actual hardware.
This is a large change, as it moves RCU grace-period
initialization and cleanup, along with quiescent-state forcing,
from softirq to a kthread. However, it appears to be in
quite good shape (famous last words). Posted to LKML at
https://lkml.org/lkml/2012/9/20/427.
2. Updates to documentation and rcutorture, the latter category
including keeping statistics on CPU-hotplug latencies and
fixing some initialization-time races. Posted to LKML at
https://lkml.org/lkml/2012/8/30/193.
3. Miscellaneous fixes and improvements, posted to LKML at
https://lkml.org/lkml/2012/8/30/199.
4. CPU-hotplug fixes and improvements, posted to LKML at
https://lkml.org/lkml/2012/8/30/292 for first three and at
https://lkml.org/lkml/2012/8/3/416.
5. Idle-loop fixes that were omitted on an earlier submission,
posted to LKML at https://lkml.org/lkml/2012/8/30/251.
"
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 from Arnaldo Carvalho de Melo:
* The new perf_evsel__tp_sched_test 'perf test' broke the build by setting the
'ret' variable but not using it, caught by newer gcc
-Werror=unused-but-set-variable, fix from Namhyung Kim.
* pevent_parse_event should return a proper PEVENT_ERRNO__ and call
pevent_free_format on its failure path, fixes from Namhyung Kim.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
H. Peter Anvin [Tue, 25 Sep 2012 22:42:18 +0000 (15:42 -0700)]
x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space
With SMAP, the [f][x]rstor_checking() functions are no longer usable
for user-space pointers by applying a simple __force cast. Instead,
create new [f][x]rstor_user() functions which do the proper SMAP
magic.
1) Eric Dumazet discovered and fixed what turned out to be a family of
bugs. These functions were using pskb_may_pull() which might need
to reallocate the linear SKB data buffer, but the callers were not
expecting this possibility. The callers have cached pointers to the
packet header areas, and would need to reload them if we were to
continue using pskb_may_pull().
So they could end up reading garbage.
It's easier to just change these RAW4/RAW6/MIP6 routines to use
skb_header_pointer() instead of pskb_may_pull(), which won't modify
the linear SKB data area.
2) Dave Jone's syscall spammer caught a case where a non-TCP socket can
call down into the TCP keepalive code. The case basically involves
creating a raw socket with sk_protocol == IPPROTO_TCP, then calling
setsockopt(sock_fd, SO_KEEPALIVE, ...)
Fixed by Eric Dumazet.
3) Bluetooth devices do not get configured properly while being powered
on, resulting in always using legacy pairing instead of SSP. Fix
from Andrzej Kaczmarek.
4) Bluetooth cancels delayed work erroneously, put stricter checks in
place. From Andrei Emeltchenko.
5) Fix deadlock between cfg80211_mutex and reg_regdb_search_mutex in
cfg80211, from Luis R. Rodriguez.
6) Fix interrupt double release in iwlwifi, from Emmanuel Grumbach.
7) Missing module license in bcm87xx driver, from Peter Huewe.
8) Team driver can lose port changed events when adding devices to a
team, fix from Jiri Pirko.
9) Fix endless loop when trying ot unregister PPPOE device in zombie
state, from Xiaodong Xu.
10) batman-adv layer needs to set MAC address of software device
earlier, otherwise we call tt_local_add with it uninitialized.
11) Fix handling of KSZ8021 PHYs, it's matched currently by KS8051 but
that doesn't program the device properly. From Marek Vasut.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
ipv6: mip6: fix mip6_mh_filter()
ipv6: raw: fix icmpv6_filter()
net: guard tcp_set_keepalive() to tcp sockets
phy/micrel: Add missing header to micrel_phy.h
phy/micrel: Rename KS80xx to KSZ80xx
phy/micrel: Implement support for KSZ8021
batman-adv: Fix symmetry check / route flapping in multi interface setups
batman-adv: Fix change mac address of soft iface.
pppoe: drop PPPOX_ZOMBIEs in pppoe_release
team: send port changed when added
ipv4: raw: fix icmp_filter()
net/phy/bcm87xx: Add MODULE_LICENSE("GPL") to GPL driver
iwlwifi: don't double free the interrupt in failure path
cfg80211: fix possible circular lock on reg_regdb_search()
Bluetooth: Fix not removing power_off delayed work
Bluetooth: Fix freeing uninitialized delayed works
Bluetooth: mgmt: Fix enabling LE while powered off
Bluetooth: mgmt: Fix enabling SSP while powered off
Paul E. McKenney [Tue, 25 Sep 2012 17:01:45 +0000 (10:01 -0700)]
Merge remote-tracking branch 'tip/smp/hotplug' into next.2012.09.25b
The conflicts between kernel/rcutree.h and kernel/rcutree_plugin.h
were due to adjacent insertions and deletions, which were resolved
by simply accepting the changes on both branches.
Merge misc fixes from Andrew Morton:
"One maintainer change and three bugfixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (4 commits)
c/r: prctl: fix build error for no-MMU case
lib/flex_proportions.c: fix corruption of denominator in flexible proportions
checksyscalls: fix "here document" handling
pwm-backlight: take over maintenance
Mark Salter [Tue, 25 Sep 2012 00:17:38 +0000 (17:17 -0700)]
c/r: prctl: fix build error for no-MMU case
Commit 1ad75b9e1628 ("c/r: prctl: add minimal address test to
PR_SET_MM") added some address checking to prctl_set_mm() used by
checkpoint-restore. This causes a build error for no-MMU systems:
kernel/sys.c: In function 'prctl_set_mm':
kernel/sys.c:1868:34: error: 'mmap_min_addr' undeclared (first use in this function)
The test for mmap_min_addr doesn't make a lot of sense for no-MMU code
as noted in commit 6e1415467614 ("NOMMU: Optimise away the
{dac_,}mmap_min_addr tests").
This patch defines mmap_min_addr as 0UL in the no-MMU case so that the
compiler will optimize away tests for "addr < mmap_min_addr".
Signed-off-by: Mark Salter <msalter@redhat.com> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: <stable@vger.kernel.org> [3.6.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Tue, 25 Sep 2012 00:17:35 +0000 (17:17 -0700)]
lib/flex_proportions.c: fix corruption of denominator in flexible proportions
When racing with CPU hotplug, percpu_counter_sum() can return negative
values for the number of observed events.
This confuses fprop_new_period(), which uses unsigned type and as a
result number of events is set to big *positive* number. From that
moment on, things go pear shaped and can result e.g. in division by
zero as denominator is later truncated to 32-bits.
This bug causes a divide-by-zero oops in bdi_dirty_limit() in Borislav's
3.6.0-rc6 based kernel.
Fix the issue by using a signed type in fprop_new_period(). That makes
us bail out from the function without doing anything (mistakenly)
thinking there are no events to age. That makes aging somewhat
inaccurate but getting accurate data would be rather hard.
Signed-off-by: Jan Kara <jack@suse.cz> Reported-by: Borislav Petkov <bp@amd64.org> Reported-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"echo" doesn't read from stdin, therefore the checksyscalls script didn't
warn about not implemented system calls anymore since 29dc54c6
("checksyscalls: Use arch/x86/syscalls/syscall_32.tbl as source").
Use "cat" instead of "echo" which handles this correctly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michal Marek <mmarek@suse.cz> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Namhyung Kim [Tue, 25 Sep 2012 02:20:28 +0000 (11:20 +0900)]
perf test: Fix build failure
The commit 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint
format fields") added following build error:
CC builtin-test.o
builtin-test.c: In function ‘perf_evsel__test_field’:
builtin-test.c:1216:6: error: variable ‘ret’ set but not used [-Werror=unused-but-set-variable]
builtin-test.c: In function ‘perf_evsel__tp_sched_test’:
builtin-test.c:1242:6: error: variable ‘ret’ set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors
make: *** [builtin-test.o] Error 1
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1348539628-3821-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
idle.2012.09.23a fixes architectures for which RCU no longer considered
the idle loop to be a quiescent state due to earlier
adaptive-dynticks changes. Affected architectures are alpha,
cris, frv, h8300, m32r, m68k, mn10300, parisc, score, xtensa,
and ia64.
Paul Mundt [Tue, 25 Sep 2012 02:51:05 +0000 (11:51 +0900)]
sh: pfc: Fix up GPIO mux type reconfig case.
Some drivers need to switch pin states between GPIO and pin function at
runtime, which was inadvertently broken in the pinctrl driver for GPIOs
being bound to a specific direction.
This fixes up the request path to ensure that previously configured GPIOs
don't cause us to inadvertently error out with an unsupported mux on
reconfig, which in practice is primarily aimed at trapping pull-up/down
users that have yet to be implemented under the new API.
Fixes up regressions in the TPU PWM driver, amongst others.
David S. Miller [Tue, 25 Sep 2012 02:00:00 +0000 (22:00 -0400)]
Merge branch 'for-davem' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
John W. Linville says:
====================
Please pull this last(?) batch of fixes intended for 3.6...
For the Bluetooth bits, Gustavo says this:
"Here goes probably my last update to 3.6. It includes the two patches
you were ok last week(from Andrzej Kaczmarek), those are critical
ones, and two other fixes one for a system crash and the other for
a missing lockdep annotation."
The referenced fixes from Andrzej prevent attempts to configure devices
that are powered-off.
Along with the Bluetooth fixes, there are a couple of 802.11 fixes.
Emmanuel Grumbach gives us an iwlwifi fix to prevent releasing an
interrupt twice. Luis R. Rodriguez provides a fix for a possible
circular lock dependency in the cfg80211 regulatory enforcement code.
All of these have been in linux-next for a few days. I hope they are
not too late to make the 3.6 release!
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull tile gxio ABI fix from Chris Metcalf:
"This fixes a last-minute change in the Tilera hypervisor ABI for TRIO
(PCI root complex) support. We've locked in this ABI going forward
and will make sure no further ABI changes like this occur."
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
tile: gxio iorpc numbering change for TRIO interface
Merge tag 'stable/for-linus-3.6-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull a Xen fix from Konrad Rzeszutek Wilk:
"It is a bug-fix when we run the initial PV guest on a AMD K8 machine
and have CONFIG_AMD_NUMA enabled and detect the NUMA topology from the
Northbridge.
We end up in the situation where the initial domain gets too much
information and gets confused and crashes - the fix is to restrict the
domain to get the information - and we do it by just disabling NUMA on
the PV guest (the hypervisor is still able to do its proper NUMA
allocations of guests).
It is OK to disable the PV guest from accessing NUMA data as right now
we do not inject any NUMA node information to the PV guests. When we
do get to that point, then this patch will have to be reverted."
* Disable PV NUMA support as we do not do anything with it (yet) and it
can cause bootup crashes on certain AMD machines.
* tag 'stable/for-linus-3.6-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/boot: Disable NUMA for PV guests.
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull two ceph fixes from Sage Weil:
"The first fixes a leak in the rbd setup error path, and the second
fixes a more serious problem with mismatched kmap/kunmap that surfaced
after the recent refactoring work."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: only kunmap kmapped pages
rbd: drop dev reference on error in rbd_open()
Marek Vasut [Sun, 23 Sep 2012 16:58:51 +0000 (16:58 +0000)]
phy/micrel: Add missing header to micrel_phy.h
The license header was missing in micrel_phy.h . This patch adds
one.
Signed-off-by: Marek Vasut <marex@denx.de> Cc: David J. Choi <david.choi@micrel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Marek Vasut [Sun, 23 Sep 2012 16:58:50 +0000 (16:58 +0000)]
phy/micrel: Rename KS80xx to KSZ80xx
There is no such part as KS8001, KS8041 or KS8051. There are only
KSZ8001, KSZ8041 and KSZ8051. Rename these parts as such to match
the Micrel naming.
Signed-off-by: Marek Vasut <marex@denx.de> Cc: David J. Choi <david.choi@micrel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Cc: Linux ARM kernel <linux-arm-kernel@lists.infradead.org> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Marek Vasut [Sun, 23 Sep 2012 16:58:49 +0000 (16:58 +0000)]
phy/micrel: Implement support for KSZ8021
The KSZ8021 PHY was previously caught by KS8051, which is not correct.
This PHY needs additional setup if it is strapped for address 0. In such
case an reserved bit must be written in the 0x16, "Operation Mode Strap
Override" register. According to the KS8051 datasheet, that bit means
"PHY Address 0 in non-broadcast" and it indeed behaves as such on KSZ8021.
The issue where the ethernet controller (Freescale FEC) did not communicate
with network is fixed by writing this bit as 1.
Signed-off-by: Marek Vasut <marex@denx.de> Cc: David J. Choi <david.choi@micrel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Chris Metcalf [Mon, 24 Sep 2012 18:57:58 +0000 (14:57 -0400)]
tile: gxio iorpc numbering change for TRIO interface
An ABI numbering change was made in the hypervisor for Tilera's 4.1
MDE release (just shipped). It's incompatible with the previous 4.0
release ABI numbering, so we track the new numbering going forward.
We plan to avoid modifying ABI numbering for these interfaces again.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
* Convert the trace builtins to use the growing evsel/evlist
tracepoint infrastructure, removing several open coded constructs
like switch like series of strcmp to dispatch events, etc.
Basically what had already been showcased in 'perf sched'.
* Add evsel constructor for tracepoints, that uses libtraceevent
just to parse the /format events file, use it in a new 'perf test'
to make sure the libtraceevent format parsing regressions can
be more readily caught.
* Some strange errors were happening in some builds, but not on the
next, reported by several people, problem was some parser related
files, generated during the build, didn't had proper make deps,
fix from Eric Sandeen.
* Fix some compiling errors on 32-bit, from Feng Tang.
* Don't use sscanf extension %as, not available on bionic, reimplementation
by Irina Tirdea.
* Fix bfd.h/libbfd detection with recent binutils, from Markus Trippelsdorf.
* Introduce struct and cache information about the environment where a
perf.data file was captured, from Namhyung Kim.
* Fix several error paths in libtraceevent, from Namhyung Kim.
Print event causing perf_event_open() to fail in 'perf record',
from Stephane Eranian.
* New 'kvm' analysis tool, from Xiao Guangrong.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf evsel: Provide a new constructor for tracepoints
The existing constructor receives a perf_event_attr filled with the
event type and the config.
To reduce the boilerplate for tracepoints, provide a new constructor,
perf_evsel__newtp() that receives the tracepoint name and will open
the debugfs file, call into libtraceevent new pevent_parse_format file
to fill its ->tp_format member, so that users can then just call
perf_evsel__field() to access its fields.
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@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/n/tip-6du8dl1hz0y5l4cybodye7hn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools lib traceevent: Carve out events format parsing routine
The pevent_parse_event() routine will parse a events/sys/tp/format file
and add an event_format instance to the pevent struct.
This patch introduces a pevent_parse_format() routine with just the bits
needed to parse the event/sys/tp/format file and just return the
event_format instance, useful for when all we want is to parse the
format file, without requiring the pevent struct.
Acked-by: Steven Rostedt <rostedt@goodmis.org> 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@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/n/tip-lge0afl47arh86om0m6a5bqr@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Wed, 19 Sep 2012 06:58:42 +0000 (15:58 +0900)]
tools lib traceevent: Make sure that arg->op.right is set properly
When process_op failed, @arg will be freed on a caller with type of
PRINT_OP. Thus free_arg() will try to free ->op.right field which can
have stale value if something bad happens in the middle.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1348037924-17568-3-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf uses sscanf extension %as to read and allocate a string in the same
step. This is a non-standard extension only present in new versions of
glibc.
Replacing the use of sscanf and %as with strtok_r calls in order to
parse a given string into its components. This is needed in Android
since bionic does not support
%as extension for sscanf.
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1348173470-4936-1-git-send-email-irina.tirdea@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Mon, 24 Sep 2012 08:15:03 +0000 (17:15 +0900)]
perf header: Remove perf_header__read_feature
Because its only user builtin-kvm::get_cpu_isa() has gone, It can be
removed safely. In general, we have the feature information in
perf_session_env already, no need to read it again.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Dong Hao <haodong@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1348474503-15070-7-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Mon, 24 Sep 2012 08:15:00 +0000 (17:15 +0900)]
perf header: Use pre-processed session env when printing
From now on each feature information is processed and saved in perf
header so that it can be used for printing. The event desc and branch
stack features are not touched since they're not saved.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> 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> Link: http://lkml.kernel.org/r/1348474503-15070-4-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Mon, 24 Sep 2012 08:14:59 +0000 (17:14 +0900)]
perf header: Add ->process callbacks to most of features
From now on each feature information is processed and saved in perf
header so that it can be used wherever needed. The BRANCH_STACK feature
is an exception since it needs nothing to be done.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> 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> Link: http://lkml.kernel.org/r/1348474503-15070-3-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Mon, 24 Sep 2012 08:14:58 +0000 (17:14 +0900)]
perf header: Add struct perf_session_env
The struct perf_session_env will preserve environment information at the
time of perf record. It can be accessed anytime after parsing a
perf.data file if needed.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1348474503-15070-2-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use zalloc for the malloc+memset open coded sequence.
Fix leak on the #ifdef'ed C state handling and when detecting invalid
data in p_state_change().
Cc: Arjan van de Ven <arjan@linux.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@gmail.com> 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-v9x3q9rv4caxtox7wtjpchq5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf lock: Use perf_evsel__intval and perf_session__set_tracepoints_handlers
Following the model of 'perf sched':
. raw_field_value searches first on the common fields, that are unused
in this tool
. Leave using perf_evsel__intval to the actual handlers, some may not
need to incur some of the cost because they may not need all the
fields values.
. Using perf_session__set_tracepoints_handlers will save all those
strcmp to find the right handler at sample processing time, do it just
once and get the handler from evsel->handler.func.
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@gmail.com> 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-v9x3q9rv4caxtox7wtjpchq5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf kmem: Use perf_evsel__intval and perf_session__set_tracepoints_handlers
Following the model of 'perf sched':
. raw_field_value searches first on the common fields, that are unused
in this tool
. Using perf_session__set_tracepoints_handlers will save all those
strcmp to find the right handler at sample processing time, do it just
once and get the handler from evsel->handler.func.
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@gmail.com> 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-v9x3q9rv4caxtox7wtjpchq5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Using plain raw_field_value(evsel->tp_format) will look at the common
fields as well, and since this tool doesn't need those, speed it up a
bit by looking at just the event specific fields.
Also in general use just evsel and sample, just like was done in 'perf
sched'.
v2: Fixed up test against evsel->name, that contains the subsys name
too, by David Ahern.
Cc: David Ahern <dsahern@gmail.com> Cc: Dong Hao <haodong@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-v9x3q9rv4caxtox7wtjpchq5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The hypervisor is in charge of allocating the proper "NUMA" memory
and dealing with the CPU scheduler to keep them bound to the proper
NUMA node. The PV guests (and PVHVM) have no inkling of where they
run and do not need to know that right now. In the future we will
need to inject NUMA configuration data (if a guest spans two or more
NUMA nodes) so that the kernel can make the right choices. But those
patches are not yet present.
In the meantime, disable the NUMA capability in the PV guest, which
also fixes a bootup issue. Andre says:
"we see Dom0 crashes due to the kernel detecting the NUMA topology not
by ACPI, but directly from the northbridge (CONFIG_AMD_NUMA).
This will detect the actual NUMA config of the physical machine, but
will crash about the mismatch with Dom0's virtual memory. Variation of
the theme: Dom0 sees what it's not supposed to see.
This happens with the said config option enabled and on a machine where
this scanning is still enabled (K8 and Fam10h, not Bulldozer class)
so we just disable NUMA scanning by setting numa_off=1.
CC: stable@vger.kernel.org Reported-and-Tested-by: Andre Przywara <andre.przywara@amd.com> Acked-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild fixes from Michal Marek:
"There are two more kbuild fixes for 3.6.
One fixes a race between x86's archscripts target and the rule
(re)building scripts/basic/fixdep. The second is a fix for the
previous attempt at fixing make firmware_install with make 3.82.
This new solution should work with any version of GNU make"
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
x86/kbuild: archscripts depends on scripts_basic
firmware: fix directory creation rule matching with make 3.80
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
Pull hwmon subsystem fixes from Jean Delvare.
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (fam15h_power) Tweak runavg_range on resume
hwmon: (coretemp) Use get_online_cpus to avoid races involving CPU hotplug
hwmon: (via-cputemp) Use get_online_cpus to avoid races involving CPU hotplug
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is a set of four essential fixes: two oops related (bnx2i,
virtio-scsi), one data corruption related (hpsa) and one failure to
boot due to interrupt routing issues (mpt2ss).
Signed-off-by: James Bottomley <JBottomley@Parallels.com>"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
[SCSI] hpsa: fix handling of protocol error
[SCSI] mpt2sas: Fix for issue - Unable to boot from the drive connected to HBA
[SCSI] bnx2i: Fixed NULL ptr deference for 1G bnx2 Linux iSCSI offload
[SCSI] scsi: virtio-scsi: Fix address translation failure of HighMem pages used by sg list
edac_mc: edac_mc_free() cannot assume mem_ctl_info is registered in sysfs.
Fix potential NULL pointer dereference in edac_unregister_sysfs() on
system boot introduced in 3.6-rc1.
Since commit 7a623c039 ("edac: rewrite the sysfs code to use struct
device") edac_mc_alloc() no longer initializes embedded kobjects in
struct mem_ctl_info. Therefore edac_mc_free() can no longer simply
decrement a kobject reference count to free the allocated memory unless
the memory controller driver module had also called edac_mc_add_mc().
Now edac_mc_free() will check if the newly embedded struct device has
been registered with sysfs before using either the standard device
release functions or freeing the data structures itself with logic
pulled out of the error path of edac_mc_alloc().
The BUG this patch resolves for me:
BUG: unable to handle kernel NULL pointer dereference at (null)
EIP is at __wake_up_common+0x1a/0x6a
Process modprobe (pid: 933, ti=f3dc6000 task=f3db9520 task.ti=f3dc6000)
Call Trace:
complete_all+0x3f/0x50
device_pm_remove+0x23/0xa2
device_del+0x34/0x142
edac_unregister_sysfs+0x3b/0x5c [edac_core]
edac_mc_free+0x29/0x2f [edac_core]
e7xxx_probe1+0x268/0x311 [e7xxx_edac]
e7xxx_init_one+0x56/0x61 [e7xxx_edac]
local_pci_probe+0x13/0x15
...
and that code block seem to mess things up in several ways (double free, memory
leak, out-of-bound reads etc.):
L422: The iterator "chn" and bound "tot_channels" are totally wrong. Should be
"row" and "tot_csrows" respectively. Which means either memory leak, or
out-of-bound reads (which if does not trigger an immediate page fault
error, will further lead to kfree() on random addresses).
L425: The inner loop is reusing the same iterator "chn" as the outer loop,
which could lead to premature end of the outer loop, and hence memory leak.
L429: The array index 'i' in mci->csrows[i] is a temporary value used in
previous loops, and won't change at all in the current loop. Which
means either out-of-bound read and possibly kfree(random number), or the
same mci->csrows[i] get freed once and again, and possibly double free
for the kfree(csr) in L427.
L426/L427: a kfree(csr->channels) is needed in between to avoid leaking the memory.
The buggy code was introduced by commit de3910eb ("edac: change the mem
allocation scheme to make Documentation/kobject.txt happy") in the 3.6-rc1
merge window. Fix it by freeing up resources in this order:
batman-adv: Fix symmetry check / route flapping in multi interface setups
If receiving an OGM from a neighbor other than the currently selected
and if it has the same TQ then we are supposed to switch if this
neighbor provides a more symmetric link than the currently selected one.
However this symmetry check currently is broken if the interface of the
neighbor we received the OGM from and the one of the currently selected
neighbor differ: We are currently trying to determine the symmetry of the
link towards the selected router via the link we received the OGM from
instead of just checking via the link towards the currently selected
router.
This leads to way more route switches than necessary and can lead to
permanent route flapping in many common multi interface setups.
This patch fixes this issue by using the right interface for this
symmetry check.
Into function interface_set_mac_addr, the function tt_local_add was
invoked before updating dev->dev_addr. The new MAC address was not
tagged as NoPurge.
Andreas Herrmann [Sun, 23 Sep 2012 18:27:32 +0000 (20:27 +0200)]
hwmon: (fam15h_power) Tweak runavg_range on resume
The quirk introduced with commit 00250ec90963b7ef6678438888f3244985ecde14 (hwmon: fam15h_power: fix
bogus values with current BIOSes) is not only required during driver
load but also when system resumes from suspend. The BIOS might set the
previously recommended (but unsuitable) initilization value for the
running average range register during resume.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Tested-by: Andreas Hartmann <andihartmann@01019freenet.de> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: stable@vger.kernel.org # 3.0+
hwmon: (coretemp) Use get_online_cpus to avoid races involving CPU hotplug
coretemp_init loops with for_each_online_cpu, adding platform_devices
and sysfs interfaces, then calls register_hotcpu_notifier. There is a
race if a CPU is offlined or onlined after the loop, but before
register_hotcpu_notifier. The race might result in the absence of a
platform_device+sysfs interface for an online CPU, or the presence of
a platform_device+sysfs interface for an offline CPU. A similar race
occurs during coretemp_exit, after the module calls
unregister_hotcpu_notifier, but before it unregisters all devices, a
CPU might offline and a device for an offline CPU will exist for a
short while.
This fix surrounds for_each_online_cpu and register_hotcpu_notifier
with get_online_cpus+put_online_cpus; and surrounds
unregister_hotcpu_notifier and device unregistering with
get_online_cpus+put_online_cpus.
Build tested.
Signed-off-by: Silas Boyd-Wickizer <sbw@mit.edu> Signed-off-by: Jean Delvare <khali@linux-fr.org>
hwmon: (via-cputemp) Use get_online_cpus to avoid races involving CPU hotplug
via_cputemp_init loops with for_each_online_cpu, adding
platform_devices, then calls register_hotcpu_notifier. If a CPU is
offlined between the loop and register_hotcpu_notifier, then later
onlined, via_cputemp_device_add will attempt to add platform devices
with the same ID. A similar race occurs during via_cputemp_exit,
after the module calls unregister_hotcpu_notifier, a CPU might offline
and a device will exist for a CPU that is offline.
This fix surrounds for_each_online_cpu and register_hotcpu_notifier
with get_online_cpus+put_online_cpus; and surrounds
unregister_hotcpu_notifier and device unregistering with
get_online_cpus+put_online_cpus.
Build tested.
Signed-off-by: Silas Boyd-Wickizer <sbw@mit.edu> Acked-by: Harald Welte <laforge@gnumonks.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Paul E. McKenney [Fri, 24 Aug 2012 20:22:13 +0000 (13:22 -0700)]
ia64: Add missing RCU idle APIs on idle loop
Traditionally, the entire idle task served as an RCU quiescent state.
But when RCU read side critical sections started appearing within the
idle loop, this traditional strategy became untenable. The fix was to
create new RCU APIs named rcu_idle_enter() and rcu_idle_exit(), which
must be called by each architecture's idle loop so that RCU can tell
when it is safe to ignore a given idle CPU.
Unfortunately, this fix was never applied to ia64, a shortcoming remedied
by this commit.
Reported by: Tony Luck <tony.luck@intel.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the xtensa's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Chris Zankel <chris@zankel.net> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in scores's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the parisc's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Parisc <linux-parisc@vger.kernel.org> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the mn10300's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: David Howells <dhowells@redhat.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the m68k's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: m68k <linux-m68k@lists.linux-m68k.org> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the m32r's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the h8300's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the Frv's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: <stable@vger.kernel.org> # 3.3+ Acked-by: David Howells <dhowells@redhat.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the Cris's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Cris <linux-cris-kernel@axis.com> Cc: <stable@vger.kernel.org> # 3.3+ Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.
So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.
This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.
Add this missing pair of calls in the Alpha's idle loop.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Tested-by: Michael Cree <mcree@orcon.net.nz> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: alpha <linux-alpha@vger.kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> # 3.3+ Reviewed-by: Josh Triplett <josh@joshtriplett.org>
cpu_idle() is called on the boot CPU by the init code with
preemption disabled. But the cpu_idle() function in alpha
doesn't handle this when it calls schedule() directly.
Fix it by converting it into schedule_preempt_disabled().
Also disable preemption before calling cpu_idle() from
secondary CPU entry code to stay consistent with this
state.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Tested-by: Michael Cree <mcree@orcon.net.nz> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: alpha <linux-alpha@vger.kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Use get_online_cpus to avoid races involving CPU hotplug
If arch/x86/kernel/cpuid.c is a module, a CPU might offline or online
between the for_each_online_cpu() loop and the call to
register_hotcpu_notifier in cpuid_init or the call to
unregister_hotcpu_notifier in cpuid_exit. The potential races can
lead to leaks/duplicates, attempts to destroy non-existant devices, or
random pointer dereferences.
Use get_online_cpus to avoid races involving CPU hotplug
If arch/x86/kernel/msr.c is a module, a CPU might offline or online
between the for_each_online_cpu(i) loop and the call to
register_hotcpu_notifier in msr_init or the call to
unregister_hotcpu_notifier in msr_exit. The potential races can lead
to leaks/duplicates, attempts to destroy non-existant devices, or
random pointer dereferences.
For example, in msr_init if:
for_each_online_cpu(i) {
err = msr_device_create(i);
if (err != 0)
goto out_class;
}
<----- CPU offlines
register_hotcpu_notifier(&msr_class_cpu_notifier);
and the CPU never onlines before msr_exit, then the module will never
call msr_device_destroy for the associated CPU.
This fix surrounds for_each_online_cpu and register_hotcpu_notifier or
unregister_hotcpu_notifier with get_online_cpus+put_online_cpus.
Tested on a VM.
Signed-off-by: Silas Boyd-Wickizer <sbw@mit.edu> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Peter Zijlstra [Mon, 20 Aug 2012 09:26:57 +0000 (11:26 +0200)]
sched: Fix load avg vs cpu-hotplug
Rabik and Paul reported two different issues related to the same few
lines of code.
Rabik's issue is that the nr_uninterruptible migration code is wrong in
that he sees artifacts due to this (Rabik please do expand in more
detail).
Paul's issue is that this code as it stands relies on us using
stop_machine() for unplug, we all would like to remove this assumption
so that eventually we can remove this stop_machine() usage altogether.
The only reason we'd have to migrate nr_uninterruptible is so that we
could use for_each_online_cpu() loops in favour of
for_each_possible_cpu() loops, however since nr_uninterruptible() is the
only such loop and its using possible lets not bother at all.
The problem Rabik sees is (probably) caused by the fact that by
migrating nr_uninterruptible we screw rq->calc_load_active for both rqs
involved.
So don't bother with fancy migration schemes (meaning we now have to
keep using for_each_possible_cpu()) and instead fold any nr_active delta
after we migrate all tasks away to make sure we don't have any skewed
nr_active accounting.
[ paulmck: Move call to calc_load_migration to CPU_DEAD to avoid
miscounting noted by Rakib. ]
Reported-by: Rakib Mullick <rakib.mullick@gmail.com> Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Posting a callback after the CPU_DEAD notifier effectively leaks
that callback unless/until that CPU comes back online. Silence is
unhelpful when attempting to track down such leaks, so this commit emits
a WARN_ON_ONCE() and unconditionally leaks the callback when an offline
CPU attempts to register a callback. The rdp->nxttail[RCU_NEXT_TAIL] is
set to NULL in the CPU_DEAD notifier and restored in the CPU_UP_PREPARE
notifier, allowing _call_rcu() to determine exactly when posting callbacks
is illegal.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
rcu: Remove _rcu_barrier() dependency on __stop_machine()
Currently, _rcu_barrier() relies on preempt_disable() to prevent
any CPU from going offline, which in turn depends on CPU hotplug's
use of __stop_machine().
This patch therefore makes _rcu_barrier() use get_online_cpus() to
block CPU-hotplug operations. This has the added benefit of removing
the need for _rcu_barrier() to adopt callbacks: Because CPU-hotplug
operations are excluded, there can be no callbacks to adopt. This
commit simplifies the code accordingly.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The print_cpu_stall_fast_no_hz() function attempts to print -1 when
the ->idle_gp_timer is not pending, but unsigned arithmetic causes it
to instead print ULONG_MAX, which is 4294967295 on 32-bit systems and 18446744073709551615 on 64-bit systems. Neither of these are the most
reader-friendly values, so this commit instead causes "timer not pending"
to be printed when ->idle_gp_timer is not pending.
Reported-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Li Zhong [Wed, 19 Sep 2012 15:52:32 +0000 (08:52 -0700)]
rcu: Move TINY_RCU quiescent state out of extended quiescent state
TINY_RCU's rcu_idle_enter_common() invokes rcu_sched_qs() in order
to inform the RCU core of the quiescent state implied by idle entry.
Of course, idle is also an extended quiescent state, so that the call
to rcu_sched_qs() speeds up RCU's invoking of any callbacks that might
be queued. This speed-up is important when entering into dyntick-idle
mode -- if there are no further scheduling-clock interrupts, the callbacks
might never be invoked, which could result in a system hang.
However, processing callbacks does event tracing, which in turn
implies RCU read-side critical sections, which are illegal in extended
quiescent states. This patch therefore moves the call to rcu_sched_qs()
so that it precedes the point at which we inform lockdep that RCU has
entered an extended quiescent state.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Michael Wang [Fri, 17 Aug 2012 04:33:34 +0000 (12:33 +0800)]
kmemleak: Replace list_for_each_continue_rcu with new interface
This patch replaces list_for_each_continue_rcu() with
list_for_each_entry_continue_rcu() to save a few lines
of code and allow removing list_for_each_continue_rcu().
Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Paul E. McKenney [Thu, 23 Aug 2012 15:34:07 +0000 (08:34 -0700)]
time: RCU permitted to stop idle entry via softirq
The can_stop_idle_tick() function complains if a softirq vector is
raised too late in the idle-entry process, presumably in order to
prevent dangling softirq invocations from being delayed across the
full idle period, which might be indefinitely long -- and if softirq
was asserted any later than the call to this function, such a delay
might well happen.
However, RCU needs to be able to use softirq to stop idle entry in
order to be able to drain RCU callbacks from the current CPU, which in
turn enables faster entry into dyntick-idle mode, which in turn reduces
power consumption. Because RCU takes this action at a well-defined
point in the idle-entry path, it is safe for RCU to take this approach.
This commit therefore silences the error message that is sometimes
produced when the going-idle CPU suddenly finds that it has an RCU_SOFTIRQ
to process. The error message will continue to be issued for other
softirq vectors.
Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Paul E. McKenney [Tue, 21 Aug 2012 19:14:19 +0000 (12:14 -0700)]
rcu: Move TINY_PREEMPT_RCU away from raw_local_irq_save()
The use of raw_local_irq_save() is unnecessary, given that local_irq_save()
really does disable interrupts. Also, it appears to interfere with lockdep.
Therefore, this commit moves to local_irq_save().
Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Paul E. McKenney [Mon, 13 Aug 2012 23:34:12 +0000 (16:34 -0700)]
rcu: Remove redundant memory barrier from __call_rcu()
The first memory barrier in __call_rcu() is supposed to order any
updates done beforehand by the caller against the actual queuing
of the callback. However, the second memory barrier (which is intended
to order incrementing the queue lengths before queuing the callback)
is also between the caller's updates and the queuing of the callback.
The second memory barrier can therefore serve both purposes.
This commit therefore removes the first memory barrier.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Paul E. McKenney [Mon, 13 Aug 2012 18:17:06 +0000 (11:17 -0700)]
rcu: Avoid spurious RCU CPU stall warnings
If a given CPU avoids the idle loop but also avoids starting a new
RCU grace period for a full minute, RCU can issue spurious RCU CPU
stall warnings. This commit fixes this issue by adding a check for
ongoing grace period to avoid these spurious stall warnings.
Reported-by: Becky Bruce <bgillbruce@gmail.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Paul E. McKenney [Fri, 10 Aug 2012 23:55:59 +0000 (16:55 -0700)]
rcu: Protect rcu_node accesses during CPU stall warnings
The print_other_cpu_stall() function accesses a number of rcu_node
fields without protection from the ->lock. In theory, this is not
a problem because the fields accessed are all integers, but in
practice the compiler can get nasty. Therefore, the commit extends
the existing critical section to cover the entire loop body.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcu_print_detail_task_stall_rnp() function invokes
rcu_preempt_blocked_readers_cgp() to verify that there are some preempted
RCU readers blocking the current grace period outside of the protection
of the rcu_node structure's ->lock. This means that the last blocked
reader might exit its RCU read-side critical section and remove itself
from the ->blkd_tasks list before the ->lock is acquired, resulting in
a segmentation fault when the subsequent code attempts to dereference
the now-NULL gp_tasks pointer.
This commit therefore moves the test under the lock. This will not
have measurable effect on lock contention because this code is invoked
only when printing RCU CPU stall warnings, in other words, in the common
case, never.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
projects / karo-tx-linux.git / log