Commit Graph

23012 Commits

Author SHA1 Message Date
James Morse
d391e55229 cpu/hotplug: Allow suspend/resume CPU to be specified
disable_nonboot_cpus() assumes that the lowest numbered online CPU is
the boot CPU, and that this is the correct CPU to run any power
management code on.

On x86 this is always correct, as CPU0 cannot (easily) by taken offline.

On arm64 CPU0 can be taken offline. For hibernate/resume this means we
may hibernate on a CPU other than CPU0. If the system is rebooted with
kexec 'CPU0' will be assigned to a different physical CPU. This
complicates hibernate/resume as now we can't trust the CPU numbers.
Arch code can find the correct physical CPU, and ensure it is online
before resume from hibernate begins, but also needs to influence
disable_nonboot_cpus()s choice of CPU.

Rename disable_nonboot_cpus() as freeze_secondary_cpus() and add an
argument indicating which CPU should be left standing. Follow the logic
in migrate_to_reboot_cpu() to use the lowest numbered online CPU if the
requested CPU is not online.
Add disable_nonboot_cpus() as an inline function that has the existing
behaviour.

Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-26 11:20:11 +01:00
Linus Torvalds
ac78bc714b Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two cputime fixes - hopefully the last ones"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cputime: Resync steal time when guest & host lose sync
  sched/cputime: Fix NO_HZ_FULL getrusage() monotonicity regression
2016-08-18 15:07:21 -07:00
Linus Torvalds
0dcb7b6f8f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also start/stop filter related fixes, a perf
  event read() fix, a fix uncovered by fuzzing, and an uprobes leak fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Check return value of the perf_event_read() IPI
  perf/core: Enable mapping of the stop filters
  perf/core: Update filters only on executable mmap
  perf/core: Fix file name handling for start/stop filters
  perf/core: Fix event_function_local()
  uprobes: Fix the memcg accounting
  perf intel-pt: Fix occasional decoding errors when tracing system-wide
  tools: Sync kvm related header files for arm64 and s390
  perf probe: Release resources on error when handling exit paths
  perf probe: Check for dup and fdopen failures
  perf symbols: Fix annotation of objects with debuginfo files
  perf script: Don't disable use_callchain if input is pipe
  perf script: Show proper message when failed list scripts
  perf jitdump: Add the right header to get the major()/minor() definitions
  perf ppc64le: Fix build failure when libelf is not present
  perf tools mem: Fix -t store option for record command
  perf intel-pt: Fix ip compression
2016-08-18 15:04:53 -07:00
Linus Torvalds
395c434292 Power management updates for v4.8-rc3
- Fix a hibernate core regression resulting from uncovering a
    latent bug in its implementation of memory bitmaps by a recent
    commit (James Morse).
 
  - Use __pa() to compute a physical address in the x86-64 code
    finalizing resume from hibernation (Rafael Wysocki).
 
  - Update power management documentation related to system sleep
    states to remove outdated information from it and to add a
    description of a recently introduced hibernation debug feature
    to it (Rafael Wysocki).
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Merge tag 'pm-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "More hibernation-related material: one fix for a recent regression in
  the core, one small cleanup of the x86-64 resume code and a
  documentation update.

  Specifics:

   - Fix a hibernate core regression resulting from uncovering a latent
     bug in its implementation of memory bitmaps by a recent commit
     (James Morse).

   - Use __pa() to compute a physical address in the x86-64 code
     finalizing resume from hibernation (Rafael Wysocki).

   - Update power management documentation related to system sleep
     states to remove outdated information from it and to add a
     description of a recently introduced hibernation debug feature to
     it (Rafael Wysocki)"

* tag 'pm-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / hibernate: Fix rtree_next_node() to avoid walking off list ends
  x86/power/64: Use __pa() for physical address computation
  PM / sleep: Update some system sleep documentation
2016-08-18 11:09:43 -07:00
Wanpeng Li
03cbc73263 sched/cputime: Resync steal time when guest & host lose sync
Commit:

  5743021831 ("sched/cputime: Count actually elapsed irq & softirq time")

... fixed a bug but also triggered a regression:

On an i5 laptop, 4 pCPUs, 4vCPUs for one full dynticks guest, there are four
CPU hog processes(for loop) running in the guest, I hot-unplug the pCPUs
on host one by one until there is only one left, then observe CPU utilization
via 'top' in the guest, it shows:

  100% st for cpu0(housekeeping)
   75% st for other CPUs (nohz full mode)

However, w/o this commit it shows the correct 75% for all four CPUs.

When a guest is interrupted for a longer amount of time, missed clock ticks
are not redelivered later. Because of that, we should not limit the amount
of steal time accounted to the amount of time that the calling functions
think have passed.

However, the interval returned by account_other_time() is NOT rounded down
to the nearest jiffy, while the base interval in get_vtime_delta() it is
subtracted from is, so the max cputime limit is required to avoid underflow.

This patch fixes the regression by limiting the account_other_time() from
get_vtime_delta() to avoid underflow, and lets the other three call sites
(in account_other_time() and steal_account_process_time()) account however
much steal time the host told us elapsed.

Suggested-by: Rik van Riel <riel@redhat.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1471399546-4069-1-git-send-email-wanpeng.li@hotmail.com
[ Improved the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 11:19:48 +02:00
Peter Zijlstra
173be9a14f sched/cputime: Fix NO_HZ_FULL getrusage() monotonicity regression
Mike reports:

 Roughly 10% of the time, ltp testcase getrusage04 fails:
 getrusage04    0  TINFO  :  Expected timers granularity is 4000 us
 getrusage04    0  TINFO  :  Using 1 as multiply factor for max [us]time increment (1000+4000us)!
 getrusage04    0  TINFO  :  utime:           0us; stime:         179us
 getrusage04    0  TINFO  :  utime:        3751us; stime:           0us
 getrusage04    1  TFAIL  :  getrusage04.c:133: stime increased > 5000us:

And tracked it down to the case where the task simply doesn't get
_any_ [us]time ticks.

Update the code to assume all rtime is utime when we lack information,
thus ensuring a task that elides the tick gets time accounted.

Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Tested-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Fredrik Markstrom <fredrik.markstrom@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: stable@vger.kernel.org # 4.3+
Fixes: 9d7fb04276 ("sched/cputime: Guarantee stime + utime == rtime")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:48:46 +02:00
David Carrillo-Cisneros
71e7bc2bab perf/core: Check return value of the perf_event_read() IPI
The call to smp_call_function_single in perf_event_read() may fail if
an invalid or not online CPU index is passed. Warn user if such bug is
present and return error.

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1471467307-61171-2-git-send-email-davidcc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:35:52 +02:00
Mathieu Poirier
99f5bc9bfa perf/core: Enable mapping of the stop filters
At this time the perf_addr_filter_needs_mmap() function will _not_
return true on a user space 'stop' filter.  But stop filters need
exactly the same kind of mapping that range and start filters get.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1468860187-318-4-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:35:51 +02:00
Mathieu Poirier
12b40a2393 perf/core: Update filters only on executable mmap
Function perf_event_mmap() is called by the MM subsystem each time
part of a binary is loaded in memory.  There can be several mapping
for a binary, many times unrelated to the code section.

Each time a section of a binary is mapped address filters are
updated, event when the map doesn't pertain to the code section.
The end result is that filters are configured based on the last map
event that was received rather than the last mapping of the code
segment.

For example if we have an executable 'main' that calls library
'libcstest.so.1.0', and that we want to collect traces on code
that is in that library.  The perf cmd line for this scenario
would be:

  perf record -e cs_etm// --filter 'filter 0x72c/0x40@/opt/lib/libcstest.so.1.0' --per-thread ./main

Resulting in binaries being mapped this way:

  root@linaro-nano:~# cat /proc/1950/maps
  00400000-00401000 r-xp 00000000 08:02 33169     /home/linaro/main
  00410000-00411000 r--p 00000000 08:02 33169     /home/linaro/main
  00411000-00412000 rw-p 00001000 08:02 33169     /home/linaro/main
  7fa2464000-7fa2474000 rw-p 00000000 00:00 0
  7fa2474000-7fa25a4000 r-xp 00000000 08:02 543   /lib/aarch64-linux-gnu/libc-2.21.so
  7fa25a4000-7fa25b3000 ---p 00130000 08:02 543   /lib/aarch64-linux-gnu/libc-2.21.so
  7fa25b3000-7fa25b7000 r--p 0012f000 08:02 543   /lib/aarch64-linux-gnu/libc-2.21.so
  7fa25b7000-7fa25b9000 rw-p 00133000 08:02 543   /lib/aarch64-linux-gnu/libc-2.21.so
  7fa25b9000-7fa25bd000 rw-p 00000000 00:00 0
  7fa25bd000-7fa25be000 r-xp 00000000 08:02 38308 /opt/lib/libcstest.so.1.0
  7fa25be000-7fa25cd000 ---p 00001000 08:02 38308 /opt/lib/libcstest.so.1.0
  7fa25cd000-7fa25ce000 r--p 00000000 08:02 38308 /opt/lib/libcstest.so.1.0
  7fa25ce000-7fa25cf000 rw-p 00001000 08:02 38308 /opt/lib/libcstest.so.1.0
  7fa25cf000-7fa25eb000 r-xp 00000000 08:02 574   /lib/aarch64-linux-gnu/ld-2.21.so
  7fa25ef000-7fa25f2000 rw-p 00000000 00:00 0
  7fa25f7000-7fa25f9000 rw-p 00000000 00:00 0
  7fa25f9000-7fa25fa000 r--p 00000000 00:00 0     [vvar]
  7fa25fa000-7fa25fb000 r-xp 00000000 00:00 0     [vdso]
  7fa25fb000-7fa25fc000 r--p 0001c000 08:02 574   /lib/aarch64-linux-gnu/ld-2.21.so
  7fa25fc000-7fa25fe000 rw-p 0001d000 08:02 574   /lib/aarch64-linux-gnu/ld-2.21.so
  7ff2ea8000-7ff2ec9000 rw-p 00000000 00:00 0     [stack]
  root@linaro-nano:~#

Before 'main()' can execute 'libcstest.so.1.0' has to be loaded in
memory.  Once that has been done perf_event_mmap() has been called
4 times, with the last map starting at address 0x7fa25ce000 and
the address filter configured to start filtering when the
IP has passed over address 0x0x7fa25ce72c (0x7fa25ce000 + 0x72c).

But that is wrong since the code segment for library 'libcstest.so.1.0'
as been mapped at 0x7fa25bd000, resulting in traces not being
collected.

This patch corrects the situation by requesting that address
filters be updated only if the mapped event is for a code
segment.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1468860187-318-3-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:35:50 +02:00
Mathieu Poirier
4059ffd09d perf/core: Fix file name handling for start/stop filters
Binary file names have to be supplied for both range and start/stop
filters but the current code only processes the filename if an
address range filter is specified.  This code adds processing of
the filename for start/stop filters.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1468860187-318-2-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:35:50 +02:00
Peter Zijlstra
cca2094605 perf/core: Fix event_function_local()
Vincent reported triggering the WARN_ON_ONCE() in event_function_local().

While thinking through cases I noticed that by using event_function()
directly, we miss the inactive case usually handled by
event_function_call().

Therefore construct a blend of event_function_call() and
event_function() that handles the cases relevant to
event_function_local().

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # 4.5+
Fixes: fae3fde651 ("perf: Collapse and fix event_function_call() users")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:35:49 +02:00
Oleg Nesterov
6c4687cc17 uprobes: Fix the memcg accounting
__replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path,
it should only do this if page_check_address() fails.

This means that every enable/disable leads to unbalanced mem_cgroup_uncharge()
from put_page(old_page), it is trivial to underflow the page_counter->count
and trigger OOM.

Reported-and-tested-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: stable@vger.kernel.org # 3.17+
Fixes: 00501b531c ("mm: memcontrol: rewrite charge API")
Link: http://lkml.kernel.org/r/20160817153629.GB29724@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18 10:03:26 +02:00
Rafael J. Wysocki
6c16f42a4e Merge branch 'pm-sleep'
* pm-sleep:
  PM / hibernate: Fix rtree_next_node() to avoid walking off list ends
  x86/power/64: Use __pa() for physical address computation
  PM / sleep: Update some system sleep documentation
2016-08-18 03:27:08 +02:00
Linus Torvalds
184ca82348 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Buffers powersave frame test is reversed in cfg80211, fix from Felix
    Fietkau.

 2) Remove bogus WARN_ON in openvswitch, from Jarno Rajahalme.

 3) Fix some tg3 ethtool logic bugs, and one that would cause no
    interrupts to be generated when rx-coalescing is set to 0.  From
    Satish Baddipadige and Siva Reddy Kallam.

 4) QLCNIC mailbox corruption and napi budget handling fix from Manish
    Chopra.

 5) Fix fib_trie logic when walking the trie during /proc/net/route
    output than can access a stale node pointer.  From David Forster.

 6) Several sctp_diag fixes from Phil Sutter.

 7) PAUSE frame handling fixes in mlxsw driver from Ido Schimmel.

 8) Checksum fixup fixes in bpf from Daniel Borkmann.

 9) Memork leaks in nfnetlink, from Liping Zhang.

10) Use after free in rxrpc, from David Howells.

11) Use after free in new skb_array code of macvtap driver, from Jason
    Wang.

12) Calipso resource leak, from Colin Ian King.

13) mediatek bug fixes (missing stats sync init, etc.) from Sean Wang.

14) Fix bpf non-linear packet write helpers, from Daniel Borkmann.

15) Fix lockdep splats in macsec, from Sabrina Dubroca.

16) hv_netvsc bug fixes from Vitaly Kuznetsov, mostly to do with VF
    handling.

17) Various tc-action bug fixes, from CONG Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
  net_sched: allow flushing tc police actions
  net_sched: unify the init logic for act_police
  net_sched: convert tcf_exts from list to pointer array
  net_sched: move tc offload macros to pkt_cls.h
  net_sched: fix a typo in tc_for_each_action()
  net_sched: remove an unnecessary list_del()
  net_sched: remove the leftover cleanup_a()
  mlxsw: spectrum: Allow packets to be trapped from any PG
  mlxsw: spectrum: Unmap 802.1Q FID before destroying it
  mlxsw: spectrum: Add missing rollbacks in error path
  mlxsw: reg: Fix missing op field fill-up
  mlxsw: spectrum: Trap loop-backed packets
  mlxsw: spectrum: Add missing packet traps
  mlxsw: spectrum: Mark port as active before registering it
  mlxsw: spectrum: Create PVID vPort before registering netdevice
  mlxsw: spectrum: Remove redundant errors from the code
  mlxsw: spectrum: Don't return upon error in removal path
  i40e: check for and deal with non-contiguous TCs
  ixgbe: Re-enable ability to toggle VLAN filtering
  ixgbe: Force VLNCTRL.VFE to be set in all VMDq paths
  ...
2016-08-17 17:26:58 -07:00
James Morse
924d869675 PM / hibernate: Fix rtree_next_node() to avoid walking off list ends
rtree_next_node() walks the linked list of leaf nodes to find the next
block of pages in the struct memory_bitmap. If it walks off the end of
the list of nodes, it walks the list of memory zones to find the next
region of memory. If it walks off the end of the list of zones, it
returns false.

This leaves the struct bm_position's node and zone pointers pointing
at their respective struct list_heads in struct mem_zone_bm_rtree.

memory_bm_find_bit() uses struct bm_position's node and zone pointers
to avoid walking lists and trees if the next bit appears in the same
node/zone. It handles these values being stale.

Swap rtree_next_node()s 'step then test' to 'test-next then step',
this means if we reach the end of memory we return false and leave
the node and zone pointers as they were.

This fixes a panic on resume using AMD Seattle with 64K pages:
[    6.868732] Freezing user space processes ... (elapsed 0.000 seconds) done.
[    6.875753] Double checking all user space processes after OOM killer disable... (elapsed 0.000 seconds)
[    6.896453] PM: Using 3 thread(s) for decompression.
[    6.896453] PM: Loading and decompressing image data (5339 pages)...
[    7.318890] PM: Image loading progress:   0%
[    7.323395] Unable to handle kernel paging request at virtual address 00800040
[    7.330611] pgd = ffff000008df0000
[    7.334003] [00800040] *pgd=00000083fffe0003, *pud=00000083fffe0003, *pmd=00000083fffd0003, *pte=0000000000000000
[    7.344266] Internal error: Oops: 96000005 [#1] PREEMPT SMP
[    7.349825] Modules linked in:
[    7.352871] CPU: 2 PID: 1 Comm: swapper/0 Tainted: G        W I     4.8.0-rc1 #4737
[    7.360512] Hardware name: AMD Overdrive/Supercharger/Default string, BIOS ROD1002C 04/08/2016
[    7.369109] task: ffff8003c0220000 task.stack: ffff8003c0280000
[    7.375020] PC is at set_bit+0x18/0x30
[    7.378758] LR is at memory_bm_set_bit+0x24/0x30
[    7.383362] pc : [<ffff00000835bbc8>] lr : [<ffff0000080faf18>] pstate: 60000045
[    7.390743] sp : ffff8003c0283b00
[    7.473551]
[    7.475031] Process swapper/0 (pid: 1, stack limit = 0xffff8003c0280020)
[    7.481718] Stack: (0xffff8003c0283b00 to 0xffff8003c0284000)
[    7.800075] Call trace:
[    7.887097] [<ffff00000835bbc8>] set_bit+0x18/0x30
[    7.891876] [<ffff0000080fb038>] duplicate_memory_bitmap.constprop.38+0x54/0x70
[    7.899172] [<ffff0000080fcc40>] snapshot_write_next+0x22c/0x47c
[    7.905166] [<ffff0000080fe1b4>] load_image_lzo+0x754/0xa88
[    7.910725] [<ffff0000080ff0a8>] swsusp_read+0x144/0x230
[    7.916025] [<ffff0000080fa338>] load_image_and_restore+0x58/0x90
[    7.922105] [<ffff0000080fa660>] software_resume+0x2f0/0x338
[    7.927752] [<ffff000008083350>] do_one_initcall+0x38/0x11c
[    7.933314] [<ffff000008b40cc0>] kernel_init_freeable+0x14c/0x1ec
[    7.939395] [<ffff0000087ce564>] kernel_init+0x10/0xfc
[    7.944520] [<ffff000008082e90>] ret_from_fork+0x10/0x40
[    7.949820] Code: d2800022 8b400c21 f9800031 9ac32043 (c85f7c22)
[    7.955909] ---[ end trace 0024a5986e6ff323 ]---
[    7.960529] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

Here struct mem_zone_bm_rtree's start_pfn has been returned instead of
struct rtree_node's addr as the node/zone pointers are corrupt after
we walked off the end of the lists during mark_unsafe_pages().

This behaviour was exposed by commit 6dbecfd345 ("PM / hibernate:
Simplify mark_unsafe_pages()"), which caused mark_unsafe_pages() to call
duplicate_memory_bitmap(), which uses memory_bm_find_bit() after walking
off the end of the memory bitmap.

Fixes: 3a20cb1779 (PM / Hibernate: Implement position keeping in radix tree)
Signed-off-by: James Morse <james.morse@arm.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 13:16:36 +02:00
Daniel Borkmann
747ea55e4f bpf: fix bpf_skb_in_cgroup helper naming
While hashing out BPF's current_task_under_cgroup helper bits, it came
to discussion that the skb_in_cgroup helper name was suboptimally chosen.

Tejun says:

  So, I think in_cgroup should mean that the object is in that
  particular cgroup while under_cgroup in the subhierarchy of that
  cgroup. Let's rename the other subhierarchy test to under too. I
  think that'd be a lot less confusing going forward.

  [...]

  It's more intuitive and gives us the room to implement the real
  "in" test if ever necessary in the future.

Since this touches uapi bits, we need to change this as long as v4.8
is not yet officially released. Thus, change the helper enum and rename
related bits.

Fixes: 4a482f34af ("cgroup: bpf: Add bpf_skb_in_cgroup_proto")
Reference: http://patchwork.ozlabs.org/patch/658500/
Suggested-by: Sargun Dhillon <sargun@sargun.me>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2016-08-12 21:53:33 -07:00
Linus Torvalds
9710cb6624 Power management fixes for v4.8-rc2
- Fix the x86 identity mapping creation helpers to avoid the
    assumption that the base address of the mapping will always be
    aligned at the PGD level, as it may be aligned at the PUD level
    if address space randomization is enabled (Rafael Wysocki).
 
  - Fix the hibernation core to avoid executing tracing functions
    before restoring the processor state completely during resume
    (Thomas Garnier).
 
  - Fix a recently introduced regression in the powernv cpufreq
    driver that causes it to crash due to an out-of-bounds array
    access (Akshay Adiga).
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Merge tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "Two hibernation fixes allowing it to work with the recently added
  randomization of the kernel identity mapping base on x86-64 and one
  cpufreq driver regression fix.

  Specifics:

   - Fix the x86 identity mapping creation helpers to avoid the
     assumption that the base address of the mapping will always be
     aligned at the PGD level, as it may be aligned at the PUD level if
     address space randomization is enabled (Rafael Wysocki).

   - Fix the hibernation core to avoid executing tracing functions
     before restoring the processor state completely during resume
     (Thomas Garnier).

   - Fix a recently introduced regression in the powernv cpufreq driver
     that causes it to crash due to an out-of-bounds array access
     (Akshay Adiga)"

* tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / hibernate: Restore processor state before using per-CPU variables
  x86/power/64: Always create temporary identity mapping correctly
  cpufreq: powernv: Fix crash in gpstate_timer_handler()
2016-08-12 16:23:58 -07:00
Linus Torvalds
3bc6d8c155 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Ingo Molnar:
 "Misc fixes: a /dev/rtc regression fix, two APIC timer period
  calibration fixes, an ARM clocksource driver fix and a NOHZ
  power use regression fix"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/hpet: Fix /dev/rtc breakage caused by RTC cleanup
  x86/timers/apic: Inform TSC deadline clockevent device about recalibration
  x86/timers/apic: Fix imprecise timer interrupts by eliminating TSC clockevents frequency roundoff error
  timers: Fix get_next_timer_interrupt() computation
  clocksource/arm_arch_timer: Force per-CPU interrupt to be level-triggered
2016-08-12 13:55:06 -07:00
Rafael J. Wysocki
0aeeb3e73f Merge branches 'pm-sleep' and 'pm-cpufreq'
* pm-sleep:
  PM / hibernate: Restore processor state before using per-CPU variables
  x86/power/64: Always create temporary identity mapping correctly

* pm-cpufreq:
  cpufreq: powernv: Fix crash in gpstate_timer_handler()
2016-08-12 22:53:58 +02:00
Linus Torvalds
e6e7214fbb Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: cputime fixes, two deadline scheduler fixes and a cgroups
  scheduling fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cputime: Fix omitted ticks passed in parameter
  sched/cputime: Fix steal time accounting
  sched/deadline: Fix lock pinning warning during CPU hotplug
  sched/cputime: Mitigate performance regression in times()/clock_gettime()
  sched/fair: Fix typo in sync_throttle()
  sched/deadline: Fix wrap-around in DL heap
2016-08-12 13:51:52 -07:00
Thomas Garnier
62822e2ec4 PM / hibernate: Restore processor state before using per-CPU variables
Restore the processor state before calling any other functions to
ensure per-CPU variables can be used with KASLR memory randomization.

Tracing functions use per-CPU variables (GS based on x86) and one was
called just before restoring the processor state fully. It resulted
in a double fault when both the tracing & the exception handler
functions tried to use a per-CPU variable.

Fixes: bb3632c610 (PM / sleep: trace events for suspend/resume)
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Reported-by: Jiri Kosina <jikos@kernel.org>
Tested-by: Rafael J. Wysocki <rafael@kernel.org>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-12 22:50:42 +02:00
Linus Torvalds
ad83242a8f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, plus two uncore-PMU fixes, an uprobes fix, a
  perf-cgroups fix and an AUX events fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Add enable_box for client MSR uncore
  perf/x86/intel/uncore: Fix uncore num_counters
  uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions
  perf/core: Set cgroup in CPU contexts for new cgroup events
  perf/core: Fix sideband list-iteration vs. event ordering NULL pointer deference crash
  perf probe ppc64le: Fix probe location when using DWARF
  perf probe: Add function to post process kernel trace events
  tools: Sync cpufeatures headers with the kernel
  toops: Sync tools/include/uapi/linux/bpf.h with the kernel
  tools: Sync cpufeatures.h and vmx.h with the kernel
  perf probe: Support signedness casting
  perf stat: Avoid skew when reading events
  perf probe: Fix module name matching
  perf probe: Adjust map->reloc offset when finding kernel symbol from map
  perf hists: Trim libtraceevent trace_seq buffers
  perf script: Add 'bpf-output' field to usage message
2016-08-12 13:21:18 -07:00
Linus Torvalds
1f8083c640 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Misc fixes: lockstat fix, futex fix on !MMU systems, big endian fix
  for qrwlocks and a race fix for pvqspinlocks"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/pvqspinlock: Fix a bug in qstat_read()
  locking/pvqspinlock: Fix double hash race
  locking/qrwlock: Fix write unlock bug on big endian systems
  futex: Assume all mappings are private on !MMU systems
2016-08-12 12:46:37 -07:00
Linus Torvalds
25db69188e Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Ingo Molnar:
 "A fix for an MSI regression"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/msi: Make sure PCI MSIs are activated early
2016-08-12 12:41:51 -07:00
Frederic Weisbecker
26f2c75cd2 sched/cputime: Fix omitted ticks passed in parameter
Commit:

  f9bcf1e0e0 ("sched/cputime: Fix steal time accounting")

... fixes a leak on steal time accounting but forgets to account
the ticks passed in parameters, assuming there is only one to
take into account.

Let's consider that parameter back.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Wanpeng Li <kernellwp@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: linux-tip-commits@vger.kernel.org
Link: http://lkml.kernel.org/r/20160811125822.GB4214@lerouge
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 16:34:37 +02:00
Wanpeng Li
f9bcf1e0e0 sched/cputime: Fix steal time accounting
Commit:

  5743021831 ("sched/cputime: Count actually elapsed irq & softirq time")

... didn't take steal time into consideration with passing the noirqtime
kernel parameter.

As Paolo pointed out before:

| Why not? If idle=poll, for example, any time the guest is suspended (and
| thus cannot poll) does count as stolen time.

This patch fixes it by reducing steal time from idle time accounting when
the noirqtime parameter is true. The average idle time drops from 56.8%
to 54.75% for nohz idle kvm guest(noirqtime, idle=poll, four vCPUs running
on one pCPU).

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1470893795-3527-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:02:14 +02:00
Ingo Molnar
fdbdfefbab Merge branch 'linus' into timers/urgent, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:36:23 +02:00
Pan Xinhui
c2ace36b88 locking/pvqspinlock: Fix a bug in qstat_read()
It's obviously wrong to set stat to NULL. So lets remove it.
Otherwise it is always zero when we check the latency of kick/wake.

Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Waiman Long <Waiman.Long@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1468405414-3700-1-git-send-email-xinhui.pan@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:13:29 +02:00
Wanpeng Li
229ce63157 locking/pvqspinlock: Fix double hash race
When the lock holder vCPU is racing with the queue head:

   CPU 0 (lock holder)    CPU1 (queue head)
   ===================    =================
   spin_lock();           spin_lock();
    pv_kick_node():        pv_wait_head_or_lock():
                            if (!lp) {
                             lp = pv_hash(lock, pn);
                             xchg(&l->locked, _Q_SLOW_VAL);
                            }
                            WRITE_ONCE(pn->state, vcpu_halted);
     cmpxchg(&pn->state,
      vcpu_halted, vcpu_hashed);
     WRITE_ONCE(l->locked, _Q_SLOW_VAL);
     (void)pv_hash(lock, pn);

In this case, lock holder inserts the pv_node of queue head into the
hash table and set _Q_SLOW_VAL unnecessary. This patch avoids it by
restoring/setting vcpu_hashed state after failing adaptive locking
spinning.

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <Waiman.Long@hpe.com>
Link: http://lkml.kernel.org/r/1468484156-4521-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:13:28 +02:00
Ingo Molnar
a2071cd765 Merge branch 'linus' into locking/urgent, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:11:54 +02:00
Wanpeng Li
c0c8c9fa21 sched/deadline: Fix lock pinning warning during CPU hotplug
The following warning can be triggered by hot-unplugging the CPU
on which an active SCHED_DEADLINE task is running on:

  WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:3531 lock_release+0x690/0x6a0
  releasing a pinned lock
  Call Trace:
   dump_stack+0x99/0xd0
   __warn+0xd1/0xf0
   ? dl_task_timer+0x1a1/0x2b0
   warn_slowpath_fmt+0x4f/0x60
   ? sched_clock+0x13/0x20
   lock_release+0x690/0x6a0
   ? enqueue_pushable_dl_task+0x9b/0xa0
   ? enqueue_task_dl+0x1ca/0x480
   _raw_spin_unlock+0x1f/0x40
   dl_task_timer+0x1a1/0x2b0
   ? push_dl_task.part.31+0x190/0x190
  WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:3649 lock_unpin_lock+0x181/0x1a0
  unpinning an unpinned lock
  Call Trace:
   dump_stack+0x99/0xd0
   __warn+0xd1/0xf0
   warn_slowpath_fmt+0x4f/0x60
   lock_unpin_lock+0x181/0x1a0
   dl_task_timer+0x127/0x2b0
   ? push_dl_task.part.31+0x190/0x190

As per the comment before this code, its safe to drop the RQ lock
here, and since we (potentially) change rq, unpin and repin to avoid
the splat.

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
[ Rewrote changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@unitn.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1470274940-17976-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:02:55 +02:00
Giovanni Gherdovich
6075620b05 sched/cputime: Mitigate performance regression in times()/clock_gettime()
Commit:

  6e998916df ("sched/cputime: Fix clock_nanosleep()/clock_gettime() inconsistency")

fixed a problem whereby clock_nanosleep() followed by clock_gettime() could
allow a task to wake early. It addressed the problem by calling the scheduling
classes update_curr() when the cputimer starts.

Said change induced a considerable performance regression on the syscalls
times() and clock_gettimes(CLOCK_PROCESS_CPUTIME_ID). There are some
debuggers and applications that monitor their own performance that
accidentally depend on the performance of these specific calls.

This patch mitigates the performace loss by prefetching data in the CPU
cache, as stalls due to cache misses appear to be where most time is spent
in our benchmarks.

Here are the performance gain of this patch over v4.7-rc7 on a Sandy Bridge
box with 32 logical cores and 2 NUMA nodes. The test is repeated with a
variable number of threads, from 2 to 4*num_cpus; the results are in
seconds and correspond to the average of 10 runs; the percentage gain is
computed with (before-after)/before so a positive value is an improvement
(it's faster). The improvement varies between a few percents for 5-20
threads and more than 10% for 2 or >20 threads.

pound_clock_gettime:

    threads       4.7-rc7     patched 4.7-rc7
    [num]         [secs]      [secs (percent)]
      2           3.48        3.06 ( 11.83%)
      5           3.33        3.25 (  2.40%)
      8           3.37        3.26 (  3.30%)
     12           3.32        3.37 ( -1.60%)
     21           4.01        3.90 (  2.74%)
     30           3.63        3.36 (  7.41%)
     48           3.71        3.11 ( 16.27%)
     79           3.75        3.16 ( 15.74%)
    110           3.81        3.25 ( 14.80%)
    128           3.88        3.31 ( 14.76%)

pound_times:

    threads       4.7-rc7     patched 4.7-rc7
    [num]         [secs]      [secs (percent)]
      2           3.65        3.25 ( 11.03%)
      5           3.45        3.17 (  7.92%)
      8           3.52        3.22 (  8.69%)
     12           3.29        3.36 ( -2.04%)
     21           4.07        3.92 (  3.78%)
     30           3.87        3.40 ( 12.17%)
     48           3.79        3.16 ( 16.61%)
     79           3.88        3.28 ( 15.42%)
    110           3.90        3.38 ( 13.35%)
    128           4.00        3.38 ( 15.45%)

pound_clock_gettime and pound_clock_gettime are two benchmarks included in
the MMTests framework. They launch a given number of threads which
repeatedly call times() or clock_gettimes(). The results above can be
reproduced with cloning MMTests from github.com and running the "poundtime"
workload:

  $ git clone https://github.com/gormanm/mmtests.git
  $ cd mmtests
  $ cp configs/config-global-dhp__workload_poundtime config
  $ ./run-mmtests.sh --run-monitor $(uname -r)

The above will run "poundtime" measuring the kernel currently running on
the machine; Once a new kernel is installed and the machine rebooted,
running again

  $ cd mmtests
  $ ./run-mmtests.sh --run-monitor $(uname -r)

will produce results to compare with. A comparison table will be output
with:

  $ cd mmtests/work/log
  $ ../../compare-kernels.sh

the table will contain a lot of entries; grepping for "Amean" (as in
"arithmetic mean") will give the tables presented above. The source code
for the two benchmarks is reported at the end of this changelog for
clairity.

The cache misses addressed by this patch were found using a combination of
`perf top`, `perf record` and `perf annotate`. The incriminated lines were
found to be

    struct sched_entity *curr = cfs_rq->curr;

and

    delta_exec = now - curr->exec_start;

in the function update_curr() from kernel/sched/fair.c. This patch
prefetches the data from memory just before update_curr is called in the
interested execution path.

A comparison of the total number of cycles before and after the patch
follows; the data is obtained using `perf stat -r 10 -ddd <program>`
running over the same sequence of number of threads used above (a positive
gain is an improvement):

  threads   cycles before                 cycles after                gain

    2      19,699,563,964  +-1.19%      17,358,917,517  +-1.85%      11.88%
    5      47,401,089,566  +-2.96%      45,103,730,829  +-0.97%       4.85%
    8      80,923,501,004  +-3.01%      71,419,385,977  +-0.77%      11.74%
   12     112,326,485,473  +-0.47%     110,371,524,403  +-0.47%       1.74%
   21     193,455,574,299  +-0.72%     180,120,667,904  +-0.36%       6.89%
   30     315,073,519,013  +-1.64%     271,222,225,950  +-1.29%      13.92%
   48     321,969,515,332  +-1.48%     273,353,977,321  +-1.16%      15.10%
   79     337,866,003,422  +-0.97%     289,462,481,538  +-1.05%      14.33%
  110     338,712,691,920  +-0.78%     290,574,233,170  +-0.77%      14.21%
  128     348,384,794,006  +-0.50%     292,691,648,206  +-0.66%      15.99%

A comparison of cache miss vs total cache loads ratios, before and after
the patch (again from the `perf stat -r 10 -ddd <program>` tables):

  threads   L1 misses/total*100     L1 misses/total*100            gain
		         before                   after
      2           7.43  +-4.90%           7.36  +-4.70%           0.94%
      5          13.09  +-4.74%          13.52  +-3.73%          -3.28%
      8          13.79  +-5.61%          12.90  +-3.27%           6.45%
     12          11.57  +-2.44%           8.71  +-1.40%          24.72%
     21          12.39  +-3.92%           9.97  +-1.84%          19.53%
     30          13.91  +-2.53%          11.73  +-2.28%          15.67%
     48          13.71  +-1.59%          12.32  +-1.97%          10.14%
     79          14.44  +-0.66%          13.40  +-1.06%           7.20%
    110          15.86  +-0.50%          14.46  +-0.59%           8.83%
    128          16.51  +-0.32%          15.06  +-0.78%           8.78%

As a final note, the following shows the evolution of performance figures
in the "poundtime" benchmark and pinpoints commit 6e998916df
("sched/cputime: Fix clock_nanosleep()/clock_gettime() inconsistency") as a
major source of degradation, mostly unaddressed to this day (figures
expressed in seconds).

pound_clock_gettime:

  threads   parent of         6e998916df        4.7-rc7
	    6e998916df            itself
    2        2.23          3.68 ( -64.56%)        3.48 (-55.48%)
    5        2.83          3.78 ( -33.42%)        3.33 (-17.43%)
    8        2.84          4.31 ( -52.12%)        3.37 (-18.76%)
    12       3.09          3.61 ( -16.74%)        3.32 ( -7.17%)
    21       3.14          4.63 ( -47.36%)        4.01 (-27.71%)
    30       3.28          5.75 ( -75.37%)        3.63 (-10.80%)
    48       3.02          6.05 (-100.56%)        3.71 (-22.99%)
    79       2.88          6.30 (-118.90%)        3.75 (-30.26%)
    110      2.95          6.46 (-119.00%)        3.81 (-29.24%)
    128      3.05          6.42 (-110.08%)        3.88 (-27.04%)

pound_times:

  threads   parent of         6e998916df        4.7-rc7
	    6e998916df            itself
    2        2.27          3.73 ( -64.71%)        3.65 (-61.14%)
    5        2.78          3.77 ( -35.56%)        3.45 (-23.98%)
    8        2.79          4.41 ( -57.71%)        3.52 (-26.05%)
    12       3.02          3.56 ( -17.94%)        3.29 ( -9.08%)
    21       3.10          4.61 ( -48.74%)        4.07 (-31.34%)
    30       3.33          5.75 ( -72.53%)        3.87 (-16.01%)
    48       2.96          6.06 (-105.04%)        3.79 (-28.10%)
    79       2.88          6.24 (-116.83%)        3.88 (-34.81%)
    110      2.98          6.37 (-114.08%)        3.90 (-31.12%)
    128      3.10          6.35 (-104.61%)        4.00 (-28.87%)

The source code of the two benchmarks follows. To compile the two:

  NR_THREADS=42
  for FILE in pound_times pound_clock_gettime; do
      gcc -lrt -O2 -lpthread -DNUM_THREADS=$NR_THREADS $FILE.c -o $FILE
  done

==== BEGIN pound_times.c ====

struct tms start;

void *pound (void *threadid)
{
  struct tms end;
  int oldutime = 0;
  int utime;
  int i;
  for (i = 0; i < 5000000 / NUM_THREADS; i++) {
          times(&end);
          utime = ((int)end.tms_utime - (int)start.tms_utime);
          if (oldutime > utime) {
            printf("utime decreased, was %d, now %d!\n", oldutime, utime);
          }
          oldutime = utime;
  }
  pthread_exit(NULL);
}

int main()
{
  pthread_t th[NUM_THREADS];
  long i;
  times(&start);
  for (i = 0; i < NUM_THREADS; i++) {
    pthread_create (&th[i], NULL, pound, (void *)i);
  }
  pthread_exit(NULL);
  return 0;
}
==== END pound_times.c ====

==== BEGIN pound_clock_gettime.c ====

void *pound (void *threadid)
{
	struct timespec ts;
	int rc, i;
	unsigned long prev = 0, this = 0;

	for (i = 0; i < 5000000 / NUM_THREADS; i++) {
		rc = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
		if (rc < 0)
			perror("clock_gettime");
		this = (ts.tv_sec * 1000000000) + ts.tv_nsec;
		if (0 && this < prev)
			printf("%lu ns timewarp at iteration %d\n", prev - this, i);
		prev = this;
	}
	pthread_exit(NULL);
}

int main()
{
	pthread_t th[NUM_THREADS];
	long rc, i;
	pid_t pgid;

	for (i = 0; i < NUM_THREADS; i++) {
		rc = pthread_create(&th[i], NULL, pound, (void *)i);
		if (rc < 0)
			perror("pthread_create");
	}

	pthread_exit(NULL);
	return 0;
}
==== END pound_clock_gettime.c ====

Suggested-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1470385316-15027-2-git-send-email-ggherdovich@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:32:56 +02:00
Xunlei Pang
b8922125e4 sched/fair: Fix typo in sync_throttle()
We should update cfs_rq->throttled_clock_task, not
pcfs_rq->throttle_clock_task.

The effects of this bug was probably occasionally erratic
group scheduling, particularly in cgroups-intense workloads.

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
[ Added changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 55e16d30bd ("sched/fair: Rework throttle_count sync")
Link: http://lkml.kernel.org/r/1468050862-18864-1-git-send-email-xlpang@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:32:55 +02:00
Tommaso Cucinotta
a23eadfae2 sched/deadline: Fix wrap-around in DL heap
Current code in cpudeadline.c has a bug in re-heapifying when adding a
new element at the end of the heap, because a deadline value of 0 is
temporarily set in the new elem, then cpudl_change_key() is called
with the actual elem deadline as param.

However, the function compares the new deadline to set with the one
previously in the elem, which is 0.  So, if current absolute deadlines
grew so much to have negative values as s64, the comparison in
cpudl_change_key() makes the wrong decision.  Instead, as from
dl_time_before(), the kernel should handle correctly abs deadlines
wrap-arounds.

This patch fixes the problem with a minimally invasive change that
forces cpudl_change_key() to heapify up in this case.

Signed-off-by: Tommaso Cucinotta <tommaso.cucinotta@sssup.it>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Luca Abeni <luca.abeni@unitn.it>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1468921493-10054-2-git-send-email-tommaso.cucinotta@sssup.it
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:32:55 +02:00
David Carrillo-Cisneros
db4a835601 perf/core: Set cgroup in CPU contexts for new cgroup events
There's a perf stat bug easy to observer on a machine with only one cgroup:

  $ perf stat -e cycles -I 1000 -C 0 -G /
  #          time             counts unit events
      1.000161699      <not counted>      cycles                    /
      2.000355591      <not counted>      cycles                    /
      3.000565154      <not counted>      cycles                    /
      4.000951350      <not counted>      cycles                    /

We'd expect some output there.

The underlying problem is that there is an optimization in
perf_cgroup_sched_{in,out}() that skips the switch of cgroup events
if the old and new cgroups in a task switch are the same.

This optimization interacts with the current code in two ways
that cause a CPU context's cgroup (cpuctx->cgrp) to be NULL even if a
cgroup event matches the current task. These are:

  1. On creation of the first cgroup event in a CPU: In current code,
  cpuctx->cpu is only set in perf_cgroup_sched_in, but due to the
  aforesaid optimization, perf_cgroup_sched_in will run until the next
  cgroup switches in that CPU. This may happen late or never happen,
  depending on system's number of cgroups, CPU load, etc.

  2. On deletion of the last cgroup event in a cpuctx: In list_del_event,
  cpuctx->cgrp is set NULL. Any new cgroup event will not be sched in
  because cpuctx->cgrp == NULL until a cgroup switch occurs and
  perf_cgroup_sched_in is executed (updating cpuctx->cgrp).

This patch fixes both problems by setting cpuctx->cgrp in list_add_event,
mirroring what list_del_event does when removing a cgroup event from CPU
context, as introduced in:

  commit 68cacd2916 ("perf_events: Fix stale ->cgrp pointer in update_cgrp_time_from_cpuctx()")

With this patch, cpuctx->cgrp is always set/clear when installing/removing
the first/last cgroup event in/from the CPU context. With cpuctx->cgrp
correctly set, event_filter_match works as intended when events are
sched in/out.

After the fix, the output is as expected:

  $ perf stat -e cycles -I 1000 -a -G /
  #         time             counts unit events
     1.004699159          627342882      cycles                    /
     2.007397156          615272690      cycles                    /
     3.010019057          616726074      cycles                    /

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1470124092-113192-1-git-send-email-davidcc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:05:52 +02:00
Peter Zijlstra
0b8f1e2e26 perf/core: Fix sideband list-iteration vs. event ordering NULL pointer deference crash
Vegard Nossum reported that perf fuzzing generates a NULL
pointer dereference crash:

> Digging a bit deeper into this, it seems the event itself is getting
> created by perf_event_open() and it gets added to the pmu_event_list
> through:
>
> perf_event_open()
>  - perf_event_alloc()
>     - account_event()
>        - account_pmu_sb_event()
>           - attach_sb_event()
>
> so at this point the event is being attached but its ->ctx is still
> NULL. It seems like ->ctx is set just a bit later in
> perf_event_open(), though.
>
> But before that, __schedule() comes along and creates a stack trace
> similar to the one above:
>
> __schedule()
>  - __perf_event_task_sched_out()
>    - perf_iterate_sb()
>      - perf_iterate_sb_cpu()
>         - event_filter_match()
>           - perf_cgroup_match()
>             - __get_cpu_context()
>               - (dereference ctx which is NULL)
>
> So I guess the question is... should the event be attached (= put on
> the list) before ->ctx gets set? Or should the cgroup code check for a
> NULL ->ctx?

The latter seems like the simplest solution. Moving the list-add later
creates a bit of a mess.

Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Tested-by: Vegard Nossum <vegard.nossum@gmail.com>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: f2fb6bef92 ("perf/core: Optimize side-band event delivery")
Link: http://lkml.kernel.org/r/20160804123724.GN6862@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 13:05:51 +02:00
Linus Torvalds
a0cba2179e Revert "printk: create pr_<level> functions"
This reverts commit 874f9c7da9.

Geert Uytterhoeven reports:
 "This change seems to have an (unintendent?) side-effect.

  Before, pr_*() calls without a trailing newline characters would be
  printed with a newline character appended, both on the console and in
  the output of the dmesg command.

  After this commit, no new line character is appended, and the output
  of the next pr_*() call of the same type may be appended, like in:

    - Truncating RAM at 0x0000000040000000-0x00000000c0000000 to -0x0000000070000000
    - Ignoring RAM at 0x0000000200000000-0x0000000240000000 (!CONFIG_HIGHMEM)
    + Truncating RAM at 0x0000000040000000-0x00000000c0000000 to -0x0000000070000000Ignoring RAM at 0x0000000200000000-0x0000000240000000 (!CONFIG_HIGHMEM)"

Joe Perches says:
 "No, that is not intentional.

  The newline handling code inside vprintk_emit is a bit involved and
  for now I suggest a revert until this has all the same behavior as
  earlier"

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Requested-by: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-09 10:48:18 -07:00
Chris Metcalf
46c8f0b077 timers: Fix get_next_timer_interrupt() computation
The tick_nohz_stop_sched_tick() routine is not properly
canceling the sched timer when nothing is pending, because
get_next_timer_interrupt() is no longer returning KTIME_MAX in
that case.  This causes periodic interrupts when none are needed.

When determining the next interrupt time, we first use
__next_timer_interrupt() to get the first expiring timer in the
timer wheel.  If no timer is found, we return the base clock value
plus NEXT_TIMER_MAX_DELTA to indicate there is no timer in the
timer wheel.

Back in get_next_timer_interrupt(), we set the "expires" value
by converting the timer wheel expiry (in ticks) to a nsec value.
But we don't want to do this if the timer wheel expiry value
indicates no timer; we want to return KTIME_MAX.

Prior to commit 500462a9de ("timers: Switch to a non-cascading
wheel") we checked base->active_timers to see if any timers
were active, and if not, we didn't touch the expiry value and so
properly returned KTIME_MAX.  Now we don't have active_timers.

To fix this, we now just check the timer wheel expiry value to
see if it is "now + NEXT_TIMER_MAX_DELTA", and if it is, we don't
try to compute a new value based on it, but instead simply let the
KTIME_MAX value in expires remain.

Fixes: 500462a9de "timers: Switch to a non-cascading wheel"
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1470688147-22287-1-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-08-09 09:31:55 +02:00
Marc Zyngier
f3b0946d62 genirq/msi: Make sure PCI MSIs are activated early
Bharat Kumar Gogada reported issues with the generic MSI code, where the
end-point ended up with garbage in its MSI configuration (both for the vector
and the message).

It turns out that the two MSI paths in the kernel are doing slightly different
things:

generic MSI: disable MSI -> allocate MSI -> enable MSI -> setup EP
PCI MSI: disable MSI -> allocate MSI -> setup EP -> enable MSI

And it turns out that end-points are allowed to latch the content of the MSI
configuration registers as soon as MSIs are enabled.  In Bharat's case, the
end-point ends up using whatever was there already, which is not what you
want.

In order to make things converge, we introduce a new MSI domain flag
(MSI_FLAG_ACTIVATE_EARLY) that is unconditionally set for PCI/MSI. When set,
this flag forces the programming of the end-point as soon as the MSIs are
allocated.

A consequence of this is that we have an extra activate in irq_startup, but
that should be without much consequence.

tglx: 

 - Several people reported a VMWare regression with PCI/MSI-X passthrough. It
   turns out that the patch also cures that issue.

 - We need to have a look at the MSI disable interrupt path, where we write
   the msg to all zeros without disabling MSI in the PCI device. Is that
   correct?

Fixes: 52f518a3a7 "x86/MSI: Use hierarchical irqdomains to manage MSI interrupts"
Reported-and-tested-by: Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com>
Reported-and-tested-by: Foster Snowhill <forst@forstwoof.ru>
Reported-by: Matthias Prager <linux@matthiasprager.de>
Reported-by: Jason Taylor <jason.taylor@simplivity.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1468426713-31431-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-08-09 09:19:32 +02:00
Andreas Ziegler
574673c231 printk: Remove unnecessary #ifdef CONFIG_PRINTK
In commit 874f9c7da9 ("printk: create pr_<level> functions"), new
pr_level defines were added to printk.c.

These new defines are guarded by an #ifdef CONFIG_PRINTK - however,
there is already a surrounding #ifdef CONFIG_PRINTK starting a lot
earlier in line 249 which means the newly introduced #ifdef is
unnecessary.

Let's remove it to avoid confusion.

Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Cc: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-08 11:29:39 -07:00
Jens Axboe
1eff9d322a block: rename bio bi_rw to bi_opf
Since commit 63a4cc2486, bio->bi_rw contains flags in the lower
portion and the op code in the higher portions. This means that
old code that relies on manually setting bi_rw is most likely
going to be broken. Instead of letting that brokeness linger,
rename the member, to force old and out-of-tree code to break
at compile time instead of at runtime.

No intended functional changes in this commit.

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-07 14:41:02 -06:00
Alexei Starovoitov
a6ed3ea65d bpf: restore behavior of bpf_map_update_elem
The introduction of pre-allocated hash elements inadvertently broke
the behavior of bpf hash maps where users expected to call
bpf_map_update_elem() without considering that the map can be full.
Some programs do:
old_value = bpf_map_lookup_elem(map, key);
if (old_value) {
  ... prepare new_value on stack ...
  bpf_map_update_elem(map, key, new_value);
}
Before pre-alloc the update() for existing element would work even
in 'map full' condition. Restore this behavior.

The above program could have updated old_value in place instead of
update() which would be faster and most programs use that approach,
but sometimes the values are large and the programs use update()
helper to do atomic replacement of the element.
Note we cannot simply update element's value in-place like percpu
hash map does and have to allocate extra num_possible_cpu elements
and use this extra reserve when the map is full.

Fixes: 6c90598174 ("bpf: pre-allocate hash map elements")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-06 20:49:19 -04:00
Linus Torvalds
db8262787e Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Mostly tooling fixes and some late tooling updates, plus two perf
  related printk message fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tests bpf: Use SyS_epoll_wait alias
  perf tests: objdump output can contain multi byte chunks
  perf record: Add --sample-cpu option
  perf hists: Introduce output_resort_cb method
  perf tools: Move config/Makefile into Makefile.config
  perf tests: Add test for bitmap_scnprintf function
  tools lib: Add bitmap_and function
  tools lib: Add bitmap_scnprintf function
  tools lib: Add bitmap_alloc function
  tools lib traceevent: Ignore generated library files
  perf tools: Fix build failure on perl script context
  perf/core: Change log level for duration warning to KERN_INFO
  perf annotate: Plug filename string leak
  perf annotate: Introduce strerror for handling symbol__disassemble() errors
  perf annotate: Rename symbol__annotate() to symbol__disassemble()
  perf/x86: Modify error message in virtualized environment
  perf target: str_error_r() always returns the buffer it receives
  perf annotate: Use pipe + fork instead of popen
  perf evsel: Introduce constructor for cycles event
2016-08-06 09:10:36 -04:00
Linus Torvalds
2cfd716d27 powerpc updates for 4.8 #2
Fixes:
  - Fix early access to cpu_spec relocation from Benjamin Herrenschmidt
  - Fix incorrect event codes in power9-event-list from Madhavan Srinivasan
  - Move register_process_table() out of ppc_md from Michael Ellerman
 
 Use jump_label for [cpu|mmu]_has_feature() from Aneesh Kumar K.V, Kevin Hao and Michael Ellerman:
  - Add mmu_early_init_devtree() from Michael Ellerman
  - Move disable_radix handling into mmu_early_init_devtree() from Michael Ellerman
  - Do hash device tree scanning earlier from Michael Ellerman
  - Do radix device tree scanning earlier from Michael Ellerman
  - Do feature patching before MMU init from Michael Ellerman
  - Check features don't change after patching from Michael Ellerman
  - Make MMU_FTR_RADIX a MMU family feature from Aneesh Kumar K.V
  - Convert mmu_has_feature() to returning bool from Michael Ellerman
  - Convert cpu_has_feature() to returning bool from Michael Ellerman
  - Define radix_enabled() in one place & use static inline from Michael Ellerman
  - Add early_[cpu|mmu]_has_feature() from Michael Ellerman
  - Convert early cpu/mmu feature check to use the new helpers from Aneesh Kumar K.V
  - jump_label: Make it possible for arches to invoke jump_label_init() earlier from Kevin Hao
  - Call jump_label_init() in apply_feature_fixups() from Aneesh Kumar K.V
  - Remove mfvtb() from Kevin Hao
  - Move cpu_has_feature() to a separate file from Kevin Hao
  - Add kconfig option to use jump labels for cpu/mmu_has_feature() from Michael Ellerman
  - Add option to use jump label for cpu_has_feature() from Kevin Hao
  - Add option to use jump label for mmu_has_feature() from Kevin Hao
  - Catch usage of cpu/mmu_has_feature() before jump label init from Aneesh Kumar K.V
  - Annotate jump label assembly from Michael Ellerman
 
 TLB flush enhancements from Aneesh Kumar K.V:
  - radix: Implement tlb mmu gather flush efficiently
  - Add helper for finding SLBE LLP encoding
  - Use hugetlb flush functions
  - Drop multiple definition of mm_is_core_local
  - radix: Add tlb flush of THP ptes
  - radix: Rename function and drop unused arg
  - radix/hugetlb: Add helper for finding page size
  - hugetlb: Add flush_hugetlb_tlb_range
  - remove flush_tlb_page_nohash
 
 Add new ptrace regsets from Anshuman Khandual and Simon Guo:
  - elf: Add powerpc specific core note sections
  - Add the function flush_tmregs_to_thread
  - Enable in transaction NT_PRFPREG ptrace requests
  - Enable in transaction NT_PPC_VMX ptrace requests
  - Enable in transaction NT_PPC_VSX ptrace requests
  - Adapt gpr32_get, gpr32_set functions for transaction
  - Enable support for NT_PPC_CGPR
  - Enable support for NT_PPC_CFPR
  - Enable support for NT_PPC_CVMX
  - Enable support for NT_PPC_CVSX
  - Enable support for TM SPR state
  - Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
  - Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
  - Enable support for EBB registers
  - Enable support for Performance Monitor registers
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Merge tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull more powerpc updates from Michael Ellerman:
 "These were delayed for various reasons, so I let them sit in next a
  bit longer, rather than including them in my first pull request.

  Fixes:
   - Fix early access to cpu_spec relocation from Benjamin Herrenschmidt
   - Fix incorrect event codes in power9-event-list from Madhavan Srinivasan
   - Move register_process_table() out of ppc_md from Michael Ellerman

  Use jump_label use for [cpu|mmu]_has_feature():
   - Add mmu_early_init_devtree() from Michael Ellerman
   - Move disable_radix handling into mmu_early_init_devtree() from Michael Ellerman
   - Do hash device tree scanning earlier from Michael Ellerman
   - Do radix device tree scanning earlier from Michael Ellerman
   - Do feature patching before MMU init from Michael Ellerman
   - Check features don't change after patching from Michael Ellerman
   - Make MMU_FTR_RADIX a MMU family feature from Aneesh Kumar K.V
   - Convert mmu_has_feature() to returning bool from Michael Ellerman
   - Convert cpu_has_feature() to returning bool from Michael Ellerman
   - Define radix_enabled() in one place & use static inline from Michael Ellerman
   - Add early_[cpu|mmu]_has_feature() from Michael Ellerman
   - Convert early cpu/mmu feature check to use the new helpers from Aneesh Kumar K.V
   - jump_label: Make it possible for arches to invoke jump_label_init() earlier from Kevin Hao
   - Call jump_label_init() in apply_feature_fixups() from Aneesh Kumar K.V
   - Remove mfvtb() from Kevin Hao
   - Move cpu_has_feature() to a separate file from Kevin Hao
   - Add kconfig option to use jump labels for cpu/mmu_has_feature() from Michael Ellerman
   - Add option to use jump label for cpu_has_feature() from Kevin Hao
   - Add option to use jump label for mmu_has_feature() from Kevin Hao
   - Catch usage of cpu/mmu_has_feature() before jump label init from Aneesh Kumar K.V
   - Annotate jump label assembly from Michael Ellerman

  TLB flush enhancements from Aneesh Kumar K.V:
   - radix: Implement tlb mmu gather flush efficiently
   - Add helper for finding SLBE LLP encoding
   - Use hugetlb flush functions
   - Drop multiple definition of mm_is_core_local
   - radix: Add tlb flush of THP ptes
   - radix: Rename function and drop unused arg
   - radix/hugetlb: Add helper for finding page size
   - hugetlb: Add flush_hugetlb_tlb_range
   - remove flush_tlb_page_nohash

  Add new ptrace regsets from Anshuman Khandual and Simon Guo:
   - elf: Add powerpc specific core note sections
   - Add the function flush_tmregs_to_thread
   - Enable in transaction NT_PRFPREG ptrace requests
   - Enable in transaction NT_PPC_VMX ptrace requests
   - Enable in transaction NT_PPC_VSX ptrace requests
   - Adapt gpr32_get, gpr32_set functions for transaction
   - Enable support for NT_PPC_CGPR
   - Enable support for NT_PPC_CFPR
   - Enable support for NT_PPC_CVMX
   - Enable support for NT_PPC_CVSX
   - Enable support for TM SPR state
   - Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
   - Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
   - Enable support for EBB registers
   - Enable support for Performance Monitor registers"

* tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits)
  powerpc/mm: Move register_process_table() out of ppc_md
  powerpc/perf: Fix incorrect event codes in power9-event-list
  powerpc/32: Fix early access to cpu_spec relocation
  powerpc/ptrace: Enable support for Performance Monitor registers
  powerpc/ptrace: Enable support for EBB registers
  powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
  powerpc/ptrace: Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
  powerpc/ptrace: Enable support for TM SPR state
  powerpc/ptrace: Enable support for NT_PPC_CVSX
  powerpc/ptrace: Enable support for NT_PPC_CVMX
  powerpc/ptrace: Enable support for NT_PPC_CFPR
  powerpc/ptrace: Enable support for NT_PPC_CGPR
  powerpc/ptrace: Adapt gpr32_get, gpr32_set functions for transaction
  powerpc/ptrace: Enable in transaction NT_PPC_VSX ptrace requests
  powerpc/ptrace: Enable in transaction NT_PPC_VMX ptrace requests
  powerpc/ptrace: Enable in transaction NT_PRFPREG ptrace requests
  powerpc/process: Add the function flush_tmregs_to_thread
  elf: Add powerpc specific core note sections
  powerpc/mm: remove flush_tlb_page_nohash
  powerpc/mm/hugetlb: Add flush_hugetlb_tlb_range
  ...
2016-08-05 09:00:54 -04:00
Linus Torvalds
fb1b83d3ff Removed the MODULE_SIG_FORCE-means-no-MODULE_FORCE_LOAD patch.
Only interesting thing here is Jessica's patch to add ro_after_init support
 to modules.  The rest are all trivia.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "The only interesting thing here is Jessica's patch to add
  ro_after_init support to modules.  The rest are all trivia"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  extable.h: add stddef.h so "NULL" definition is not implicit
  modules: add ro_after_init support
  jump_label: disable preemption around __module_text_address().
  exceptions: fork exception table content from module.h into extable.h
  modules: Add kernel parameter to blacklist modules
  module: Do a WARN_ON_ONCE() for assert module mutex not held
  Documentation/module-signing.txt: Note need for version info if reusing a key
  module: Invalidate signatures on force-loaded modules
  module: Issue warnings when tainting kernel
  module: fix redundant test.
  module: fix noreturn attribute for __module_put_and_exit()
2016-08-04 09:14:38 -04:00
Jason Baron
1f69bf9c61 jump_label: remove bug.h, atomic.h dependencies for HAVE_JUMP_LABEL
The current jump_label.h includes bug.h for things such as WARN_ON().
This makes the header problematic for inclusion by kernel.h or any
headers that kernel.h includes, since bug.h includes kernel.h (circular
dependency).  The inclusion of atomic.h is similarly problematic.  Thus,
this should make jump_label.h 'includable' from most places.

Link: http://lkml.kernel.org/r/7060ce35ddd0d20b33bf170685e6b0fab816bdf2.1467837322.git.jbaron@akamai.com
Signed-off-by: Jason Baron <jbaron@akamai.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Joe Perches <joe@perches.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00
Masahiro Yamada
97f2645f35 tree-wide: replace config_enabled() with IS_ENABLED()
The use of config_enabled() against config options is ambiguous.  In
practical terms, config_enabled() is equivalent to IS_BUILTIN(), but the
author might have used it for the meaning of IS_ENABLED().  Using
IS_ENABLED(), IS_BUILTIN(), IS_MODULE() etc.  makes the intention
clearer.

This commit replaces config_enabled() with IS_ENABLED() where possible.
This commit is only touching bool config options.

I noticed two cases where config_enabled() is used against a tristate
option:

 - config_enabled(CONFIG_HWMON)
  [ drivers/net/wireless/ath/ath10k/thermal.c ]

 - config_enabled(CONFIG_BACKLIGHT_CLASS_DEVICE)
  [ drivers/gpu/drm/gma500/opregion.c ]

I did not touch them because they should be converted to IS_BUILTIN()
in order to keep the logic, but I was not sure it was the authors'
intention.

Link: http://lkml.kernel.org/r/1465215656-20569-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Stas Sergeev <stsp@list.ru>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: "Dmitry V. Levin" <ldv@altlinux.org>
Cc: yu-cheng yu <yu-cheng.yu@intel.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Will Drewry <wad@chromium.org>
Cc: Nikolay Martynov <mar.kolya@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Rafal Milecki <zajec5@gmail.com>
Cc: James Cowgill <James.Cowgill@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Mikko Rapeli <mikko.rapeli@iki.fi>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: "Luis R. Rodriguez" <mcgrof@do-not-panic.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Kalle Valo <kvalo@qca.qualcomm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Tony Wu <tung7970@gmail.com>
Cc: Huaitong Han <huaitong.han@intel.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Gelmini <andrea.gelmini@gelma.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Rabin Vincent <rabin@rab.in>
Cc: "Maciej W. Rozycki" <macro@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00
Jessica Yu
444d13ff10 modules: add ro_after_init support
Add ro_after_init support for modules by adding a new page-aligned section
in the module layout (after rodata) for ro_after_init data and enabling RO
protection for that section after module init runs.

Signed-off-by: Jessica Yu <jeyu@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-08-04 10:16:55 +09:30
Rusty Russell
bdc9f37355 jump_label: disable preemption around __module_text_address().
Steven reported a warning caused by not holding module_mutex or
rcu_read_lock_sched: his backtrace was corrupted but a quick audit
found this possible cause.  It's wrong anyway...

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-08-04 10:16:54 +09:30
Prarit Bhargava
be7de5f91f modules: Add kernel parameter to blacklist modules
Blacklisting a module in linux has long been a problem.  The current
procedure is to use rd.blacklist=module_name, however, that doesn't
cover the case after the initramfs and before a boot prompt (where one
is supposed to use /etc/modprobe.d/blacklist.conf to blacklist
runtime loading). Using rd.shell to get an early prompt is hit-or-miss,
and doesn't cover all situations AFAICT.

This patch adds this functionality of permanently blacklisting a module
by its name via the kernel parameter module_blacklist=module_name.

[v2]: Rusty, use core_param() instead of __setup() which simplifies
things.

[v3]: Rusty, undo wreckage from strsep()

[v4]: Rusty, simpler version of blacklisted()

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-08-04 10:16:53 +09:30