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  1. 11 May, 2016 15 commits
  3. 10 May, 2016 18 commits
  5. 09 May, 2016 7 commits
    • Chris Phlipot's avatar
      perf symbols: Fix handling of zero-length symbols. · 9c7b37cd
      Chris Phlipot authored 
      This change introduces a fix to symbols__find, so that it is able to
find symbols of length zero (where start == end).

The current code has the following problem:

- The current implementation of symbols__find is unable to find any symbols
  of length zero.

- The db-export framework explicitly creates zero length symbols at
  locations where no symbol currently exists.

The combination of the two above behaviors results in behavior similar
to the example below.

1. addr_location is created for a sample, but symbol is unable to be
   resolved.

2. db export creates an "unknown" symbol of length zero at that address
   and inserts it into the dso.

3. A new sample comes in at the same address, but symbol__find is unable
   to find the zero length symbol, so it is still unresolved.

4. db export sees the symbol is unresolved, and allocated a duplicate
   symbol, even though it already did this in step 2.

This behavior continues every time an address without symbol information
is seen, which causes a very large number of these symbols to be
allocated.

The effect of this fix can be observed by looking at the contents of an
exported database before/after the fix (generated with
scripts/python/export-to-postgresql.py)

Ex.
BEFORE THE CHANGE:

  example_db=# select count(*) from symbols;
   count
  --------
   900213
  (1 row)

  example_db=# select count(*) from symbols where symbols.name='unknown';
   count
  --------
   897355
  (1 row)

  example_db=# select count(*) from symbols where symbols.name!='unknown';
   count
  -------
    2858
  (1 row)

AFTER THE CHANGE:

  example_db=# select count(*) from symbols;
   count
  -------
   25217
  (1 row)

  example_db=# select count(*) from symbols where name='unknown';
   count
  -------
   22359
  (1 row)

  example_db=# select count(*) from symbols where name!='unknown';
   count
  -------
    2858
  (1 row)
Signed-off-by: default avatarChris Phlipot <cphlipot0@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1462612620-25008-1-git-send-email-cphlipot0@gmail.com
[ Moved the test to later in the rb_tree tests, as this not the likely case ]
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      9c7b37cd
    • Arnaldo Carvalho de Melo's avatar
      perf evsel: Print state of perf_event_attr.write_backward · 0a241ef4
      Arnaldo Carvalho de Melo authored 
      Now we can see if it is set when using verbose mode in various tools,
such as 'perf test':

  # perf test -vv back
  45: Test backward reading from ring buffer                   :
  --- start ---
  <SNIP>
  ------------------------------------------------------------
  perf_event_attr:
    type                             2
    size                             112
    config                           0x98
    { sample_period, sample_freq }   1
    sample_type                      IP|TID|TIME|CPU|PERIOD|RAW
    disabled                         1
    mmap                             1
    comm                             1
    task                             1
    sample_id_all                    1
    exclude_guest                    1
    mmap2                            1
    comm_exec                        1
    write_backward                   1
  ------------------------------------------------------------
  sys_perf_event_open: pid 20911  cpu -1  group_fd -1  flags 0x8
  <SNIP>
  ---- end ----
  Test backward reading from ring buffer: Ok
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-kxv05kv9qwl5of7rzfeiiwbv@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      0a241ef4
    • Wang Nan's avatar
      perf tests: Add test to check backward ring buffer · ee74701e
      Wang Nan authored 
      This test checks reading from backward ring buffer.

Test result:

  # ~/perf test 'ring buffer'
  45: Test backward reading from ring buffer                   : Ok

The test case is a while loop which calls prctl(PR_SET_NAME) multiple
times.  Each prctl should issue 2 events: one PERF_RECORD_SAMPLE, one
PERF_RECORD_COMM.

The first round creates a relative large ring buffer (256 pages). It can
afford all events. Read from it and check the count of each type of
events.

The second round creates a small ring buffer (1 page) and makes it
overwritable. Check the correctness of the buffer.
Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1462758471-89706-3-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      ee74701e
    • Wang Nan's avatar
      perf tools: Support reading from backward ring buffer · e24c7520
      Wang Nan authored 
      perf_evlist__mmap_read_backward() is introduced for reading backward
ring buffer. Since direction for reading such ring buffer is different
from the direction kernel writing to it, and since user need to fetch
most recent record from it, a perf_evlist__mmap_read_catchup() is
introduced to move the reading pointer to the end of the buffer.
Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1462758471-89706-2-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      e24c7520
    • Linus Torvalds's avatar
      Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 · b507146b
      Linus Torvalds authored 
      Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - bug in ahash SG list walking that may lead to crashes

   - resource leak in qat

   - missing RSA dependency that causes it to fail"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: rsa - select crypto mgr dependency
  crypto: hash - Fix page length clamping in hash walk
  crypto: qat - fix adf_ctl_drv.c:undefined reference to adf_init_pf_wq
  crypto: qat - fix invalid pf2vf_resp_wq logic
      b507146b
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · 26acc792
      Linus Torvalds authored 
      Pull networking fixes from David Miller:

 1) Check klogctl failure correctly, from Colin Ian King.

 2) Prevent OOM when under memory pressure in flowcache, from Steffen
    Klassert.

 3) Fix info leak in llc and rtnetlink ifmap code, from Kangjie Lu.

 4) Memory barrier and multicast handling fixes in bnxt_en, from Michael
    Chan.

 5) Endianness bug in mlx5, from Daniel Jurgens.

 6) Fix disconnect handling in VSOCK, from Ian Campbell.

 7) Fix locking of netdev list walking in get_bridge_ifindices(), from
    Nikolay Aleksandrov.

 8) Bridge multicast MLD parser can look at wrong packet offsets, fix
    from Linus Lüssing.

 9) Fix chip hang in qede driver, from Sudarsana Reddy Kalluru.

10) Fix missing setting of encapsulation before inner handling completes
    in udp_offload code, from Jarno Rajahalme.

11) Missing rollbacks during LAG join and flood configuration failures
    in mlxsw driver, from Ido Schimmel.

12) Fix error code checks in netxen driver, from Dan Carpenter.

13) Fix key size in new macsec driver, from Sabrina Dubroca.

14) Fix mlx5/VXLAN dependencies, from Arnd Bergmann.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (29 commits)
  net/mlx5e: make VXLAN support conditional
  Revert "net/mlx5: Kconfig: Fix MLX5_EN/VXLAN build issue"
  macsec: key identifier is 128 bits, not 64
  Documentation/networking: more accurate LCO explanation
  macvtap: segmented packet is consumed
  tools: bpf_jit_disasm: check for klogctl failure
  qede: uninitialized variable in qede_start_xmit()
  netxen: netxen_rom_fast_read() doesn't return -1
  netxen: reversed condition in netxen_nic_set_link_parameters()
  netxen: fix error handling in netxen_get_flash_block()
  mlxsw: spectrum: Add missing rollback in flood configuration
  mlxsw: spectrum: Fix rollback order in LAG join failure
  udp_offload: Set encapsulation before inner completes.
  udp_tunnel: Remove redundant udp_tunnel_gro_complete().
  qede: prevent chip hang when increasing channels
  net: ipv6: tcp reset, icmp need to consider L3 domain
  bridge: fix igmp / mld query parsing
  net: bridge: fix old ioctl unlocked net device walk
  VSOCK: do not disconnect socket when peer has shutdown SEND only
  net/mlx4_en: Fix endianness bug in IPV6 csum calculation
  ...
      26acc792
    • Josh Poimboeuf's avatar
      compiler-gcc: require gcc 4.8 for powerpc __builtin_bswap16() · 8634de6d
      Josh Poimboeuf authored 
      gcc support for __builtin_bswap16() was supposedly added for powerpc in
gcc 4.6, and was then later added for other architectures in gcc 4.8.

However, Stephen Rothwell reported that attempting to use it on powerpc
in gcc 4.6 fails with:

  lib/vsprintf.c:160:2: error: initializer element is not constant
  lib/vsprintf.c:160:2: error: (near initialization for 'decpair[0]')
  lib/vsprintf.c:160:2: error: initializer element is not constant
  lib/vsprintf.c:160:2: error: (near initialization for 'decpair[1]')
  ...

I'm not entirely sure what those errors mean, but I don't see them on
gcc 4.8.  So let's consider gcc 4.8 to be the official starting point
for __builtin_bswap16().

Arnd Bergmann adds:
 "I found the commit in gcc-4.8 that replaced the powerpc-specific
  implementation of __builtin_bswap16 with an architecture-independent
  one.  Apparently the powerpc version (gcc-4.6 and 4.7) just mapped to
  the lhbrx/sthbrx instructions, so it ended up not being a constant,
  though the intent of the patch was mainly to add support for the
  builtin to x86:

    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52624

  has the patch that went into gcc-4.8 and more information."

Fixes: 7322dd75 ("byteswap: try to avoid __builtin_constant_p gcc bug")
Reported-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
Tested-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8634de6d
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