Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
接近 2 年 前同步成功

通知 170
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 15 11月, 2016 1 次提交
  3. 24 10月, 2016 1 次提交
  5. 17 10月, 2016 4 次提交
    • H
      s390/dumpstack: get rid of return_address again · dcddba96
      由 Heiko Carstens 提交于 
      With commit ef6000b4 ("Disable the __builtin_return_address()
warning globally after all)" the kernel does not warn at all again if
__builtin_return_address(n) is called with n > 0.

Besides the fact that this was a false warning on s390 anyway, due to
the always present backchain, we can now revert commit 56063306
("s390/dumpstack: implement and use return_address()") again, to
simplify the code again.

After all I shouldn't have had return_address() implememted at all to
workaround this issue. So get rid of this again.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      dcddba96
    • H
      s390/disassambler: use pr_cont where appropriate · 4d062487
      由 Heiko Carstens 提交于 
      Just like for dumpstack use pr_cont instead of simple printk calls to
fix the output when disassembling a piece of code.

Before:
[    0.840627] Krnl Code: 000000000017d1c6: a77400f7            brc     7,17d3b4
[    0.840630]
                          000000000017d1ca: 92015000            mvi     0(%r5),1
[    0.840634]
                         #000000000017d1ce: a7f40001            brc     15,17d1d0

After:
[    0.831792] Krnl Code: 000000000017d13e: a77400f7            brc     7,17d32c
                          000000000017d142: 92015000            mvi     0(%r5),1
                         #000000000017d146: a7f40001            brc     15,17d148
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      4d062487
    • H
      s390/dumpstack: use pr_cont where appropriate · a7906345
      由 Heiko Carstens 提交于 
      Use pr_cont instead of simple printk calls when lines will be
continued. This fixes the kernel output of various lines printed on
e.g. a warning:

Before:
[    0.840604] Krnl PSW : 0404c00180000000 000000000017d1d2
[    0.840606]  (try_to_wake_up+0x382/0x5e0)

[    0.840610]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0
[    0.840611]  RI:0 EA:3

After:
[    0.831772] Krnl PSW : 0404c00180000000 000000000017d14a (try_to_wake_up+0x382/0x5e0)
[    0.831776]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      a7906345
    • H
      s390/dumpstack: restore reliable indicator for call traces · d0208639
      由 Heiko Carstens 提交于 
      Before merging all different stack tracers the call traces printed had
an indicator if an entry can be considered reliable or not.
Unreliable entries were put in braces, reliable not. Currently all
lines contain these extra braces.

This patch restores the old behaviour by adding an extra "reliable"
parameter to the callback functions. Only show_trace makes currently
use of it.

Before:
[    0.804751] Call Trace:
[    0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0)
[    0.804756] ([<0000000000161d64>] create_worker+0x174/0x1c0)

After:
[    0.804751] Call Trace:
[    0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0)
[    0.804756]  [<0000000000161d64>] create_worker+0x174/0x1c0

Fixes: 758d39eb ("s390/dumpstack: merge all four stack tracers")
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      d0208639
  7. 08 10月, 2016 2 次提交
  9. 20 9月, 2016 3 次提交
  11. 08 9月, 2016 1 次提交
  13. 29 8月, 2016 6 次提交
    • M
      s390/nmi: improve revalidation of fpu / vector registers · 8f149ea6
      由 Martin Schwidefsky 提交于 
      The machine check handler will do one of two things if the floating-point
control, a floating point register or a vector register can not be
revalidated:
1) if the PSW indicates user mode the process is terminated
2) if the PSW indicates kernel mode the system is stopped

To unconditionally stop the system for 2) is incorrect.

There are three possible outcomes if the floating-point control, a
floating point register or a vector registers can not be revalidated:
1) The kernel is inside a kernel_fpu_begin/kernel_fpu_end block and
   needs the register. The system is stopped.
2) No active kernel_fpu_begin/kernel_fpu_end block and the CIF_CPU bit
   is not set. The user space process needs the register and is killed.
3) No active kernel_fpu_begin/kernel_fpu_end block and the CIF_FPU bit
   is set. Neither the kernel nor the user space process needs the
   lost register. Just revalidate it and continue.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      8f149ea6
    • M
      s390/fpu: improve kernel_fpu_[begin|end] · 7f79695c
      由 Martin Schwidefsky 提交于 
      In case of nested user of the FPU or vector registers in the kernel
the current code uses the mask of the FPU/vector registers of the
previous contexts to decide which registers to save and restore.
E.g. if the previous context used KERNEL_VXR_V0V7 and the next
context wants to use KERNEL_VXR_V24V31 the first 8 vector registers
are stored to the FPU state structure. But this is not necessary
as the next context does not use these registers.

Rework the FPU/vector register save and restore code. The new code
does a few things differently:
1) A lowcore field is used instead of a per-cpu variable.
2) The kernel_fpu_end function now has two parameters just like
   kernel_fpu_begin. The register flags are required by both
   functions to save / restore the minimal register set.
3) The inline functions kernel_fpu_begin/kernel_fpu_end now do the
   update of the register masks. If the user space FPU registers
   have already been stored neither save_fpu_regs nor the
   __kernel_fpu_begin/__kernel_fpu_end functions have to be called
   for the first context. In this case kernel_fpu_begin adds 7
   instructions and kernel_fpu_end adds 4 instructions.
3) The inline assemblies in __kernel_fpu_begin / __kernel_fpu_end
   to save / restore the vector registers are simplified a bit.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      7f79695c
    • D
      s390/time: avoid races when updating tb_update_count · 67f03de5
      由 David Hildenbrand 提交于 
      The increment might not be atomic and we're not holding the
timekeeper_lock. Therefore we might lose an update to count, resulting in
VDSO being trapped in a loop. As other archs also simply update the
values and count doesn't seem to have an impact on reloading of these
values in VDSO code, let's just remove the update of tb_update_count.
Suggested-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      67f03de5
    • D
      s390/time: fixup the clock comparator on all cpus · 0c00b1e0
      由 David Hildenbrand 提交于 
      By leaving fixup_cc unset, only the clock comparator of the cpu actually
doing the sync is fixed up until now.
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      0c00b1e0
    • D
      s390/time: cleanup etr leftovers · ca64f639
      由 David Hildenbrand 提交于 
      There are still some etr leftovers and wrong comments, let's clean that up.
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      ca64f639
    • D
      s390/time: simplify stp time syncs · 41ad0220
      由 David Hildenbrand 提交于 
      The way we call do_adjtimex() today is broken. It has 0 effect, as
ADJ_OFFSET_SINGLESHOT (0x0001) in the kernel maps to !ADJ_ADJTIME
(in contrast to user space where it maps to  ADJ_OFFSET_SINGLESHOT |
ADJ_ADJTIME - 0x8001). !ADJ_ADJTIME will silently ignore all adjustments
without STA_PLL being active. We could switch to ADJ_ADJTIME or turn
STA_PLL on, but still we would run into some problems:

- Even when switching to nanoseconds, we lose accuracy.
- Successive calls to do_adjtimex() will simply overwrite any leftovers
  from the previous call (if not fully handled)
- Anything that NTP does using the sysctl heavily interferes with our
  use.
- !ADJ_ADJTIME will silently round stuff > or < than 0.5 seconds

Reusing do_adjtimex() here just feels wrong. The whole STP synchronization
works right now *somehow* only, as do_adjtimex() does nothing and our
TOD clock jumps in time, although it shouldn't. This is especially bad
as the clock could jump backwards in time. We will have to find another
way to fix this up.

As leap seconds are also not properly handled yet, let's just get rid of
all this complex logic altogether and use the correct clock_delta for
fixing up the clock comparator and keeping the sched_clock monotonic.

This change should have 0 effect on the current STP mechanism. Once we
know how to best handle sync events and leap second updates, we'll start
with a fresh implementation.
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      41ad0220
  15. 27 8月, 2016 1 次提交
  17. 24 8月, 2016 1 次提交
    • J
      ftrace: Add return address pointer to ftrace_ret_stack · 9a7c348b
      由 Josh Poimboeuf 提交于 
      Storing this value will help prevent unwinders from getting out of sync
with the function graph tracer ret_stack.  Now instead of needing a
stateful iterator, they can compare the return address pointer to find
the right ret_stack entry.

Note that an array of 50 ftrace_ret_stack structs is allocated for every
task.  So when an arch implements this, it will add either 200 or 400
bytes of memory usage per task (depending on whether it's a 32-bit or
64-bit platform).
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a95cfcc39e8f26b89a430c56926af0bb217bc0a1.1471607358.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      9a7c348b
  19. 08 8月, 2016 2 次提交
  21. 31 7月, 2016 6 次提交
  23. 18 7月, 2016 1 次提交
  25. 16 7月, 2016 1 次提交
    • D
      perf, events: add non-linear data support for raw records · 7e3f977e
      由 Daniel Borkmann 提交于 
      This patch adds support for non-linear data on raw records. It
extends raw records to have one or multiple fragments that will
be written linearly into the ring slot, where each fragment can
optionally have a custom callback handler to walk and extract
complex, possibly non-linear data.

If a callback handler is provided for a fragment, then the new
__output_custom() will be used instead of __output_copy() for
the perf_output_sample() part. perf_prepare_sample() does all
the size calculation only once, so perf_output_sample() doesn't
need to redo the same work anymore, meaning real_size and padding
will be cached in the raw record. The raw record becomes 32 bytes
in size without holes; to not increase it further and to avoid
doing unnecessary recalculations in fast-path, we can reuse
next pointer of the last fragment, idea here is borrowed from
ZERO_OR_NULL_PTR(), which should keep the perf_output_sample()
path for PERF_SAMPLE_RAW minimal.

This facility is needed for BPF's event output helper as a first
user that will, in a follow-up, add an additional perf_raw_frag
to its perf_raw_record in order to be able to more efficiently
dump skb context after a linear head meta data related to it.
skbs can be non-linear and thus need a custom output function to
dump buffers. Currently, the skb data needs to be copied twice;
with the help of __output_custom() this work only needs to be
done once. Future users could be things like XDP/BPF programs
that work on different context though and would thus also have
a different callback function.

The few users of raw records are adapted to initialize their frag
data from the raw record itself, no change in behavior for them.
The code is based upon a PoC diff provided by Peter Zijlstra [1].

  [1] http://thread.gmane.org/gmane.linux.network/421294Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      7e3f977e
  27. 14 7月, 2016 2 次提交
  29. 13 7月, 2016 1 次提交
  31. 04 7月, 2016 2 次提交
    • H
      s390: have unique symbol for __switch_to address · 46210c44
      由 Heiko Carstens 提交于 
      After linking there are several symbols for the same address that the
__switch_to symbol points to. E.g.:

000000000089b9c0 T __kprobes_text_start
000000000089b9c0 T __lock_text_end
000000000089b9c0 T __lock_text_start
000000000089b9c0 T __sched_text_end
000000000089b9c0 T __switch_to

When disassembling with "objdump -d" this results in a missing
__switch_to function. It would be named __kprobes_text_start
instead. To unconfuse objdump add a nop in front of the kprobes text
section. That way __switch_to appears again.

Obviously this solution is sort of a hack, since it also depends on
link order if this works or not. However it is the best I can come up
with for now.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      46210c44
    • H
      s390/cpuinfo: show maximum thread id · 10f4954a
      由 Heiko Carstens 提交于 
      Expose the maximum thread id with /proc/cpuinfo.
With the new line the output looks like this:

vendor_id       : IBM/S390
bogomips per cpu: 20325.00
max thread id   : 1

With this new interface it is possible to always tell the correct
number of cpu threads potentially being used by the kernel.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      10f4954a
  33. 28 6月, 2016 5 次提交