<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel.git/tools/perf/arch/powerpc, branch linux-4.18.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.
</subtitle>
<id>https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-4.18.y</id>
<link rel='self' href='https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-4.18.y'/>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/'/>
<updated>2018-10-10T06:55:59Z</updated>
<entry>
<title>perf probe powerpc: Ignore SyS symbols irrespective of endianness</title>
<updated>2018-10-10T06:55:59Z</updated>
<author>
<name>Sandipan Das</name>
</author>
<published>2018-08-28T09:08:48Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=3cc1b441a4b9164c63620915f7b46b9edbd7158e'/>
<id>urn:sha1:3cc1b441a4b9164c63620915f7b46b9edbd7158e</id>
<content type='text'>
[ Upstream commit fa694160cca6dbba17c57dc7efec5f93feaf8795 ]

This makes sure that the SyS symbols are ignored for any powerpc system,
not just the big endian ones.

Reported-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Reviewed-by: Kamalesh Babulal &lt;kamalesh@linux.vnet.ibm.com&gt;
Acked-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Fixes: fb6d59423115 ("perf probe ppc: Use the right prefix when ignoring SyS symbols on ppc")
Link: http://lkml.kernel.org/r/20180828090848.1914-1-sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>perf powerpc: Fix callchain ip filtering</title>
<updated>2018-09-26T06:39:25Z</updated>
<author>
<name>Sandipan Das</name>
</author>
<published>2018-07-10T13:58:13Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=b42c221e6c6f85bda8c32c4b3e0d2686f6e97f4c'/>
<id>urn:sha1:b42c221e6c6f85bda8c32c4b3e0d2686f6e97f4c</id>
<content type='text'>
[ Upstream commit c715fcfda5a08edabaa15508742be926b7ee51db ]

For powerpc64, redundant entries in the callchain are filtered out by
determining the state of the return address and the stack frame using
DWARF debug information.

For making these filtering decisions we must analyze the debug
information for the location corresponding to the program counter value,
i.e. the first entry in the callchain, and not the LR value; otherwise,
perf may filter out either the second or the third entry in the
callchain incorrectly.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

Case 1 - Attaching a probe at inet_pton+0x8 (binary offset 0x15af28).
         Return address is still in LR and a new stack frame is not yet
         allocated. The LR value, i.e. the second entry, should not be
	 filtered out.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000010eb10 &lt;gaih_inet.constprop.7&gt;:
  ...
    10fa48:       78 bb e4 7e     mr      r4,r23
    10fa4c:       0a 00 60 38     li      r3,10
    10fa50:       d9 b4 04 48     bl      15af28 &lt;inet_pton+0x8&gt;
    10fa54:       00 00 00 60     nop
    10fa58:       ac f4 ff 4b     b       10ef04 &lt;gaih_inet.constprop.7+0x3f4&gt;
  ...
  0000000000110450 &lt;getaddrinfo&gt;:
  ...
    1105a8:       54 00 ff 38     addi    r7,r31,84
    1105ac:       58 00 df 38     addi    r6,r31,88
    1105b0:       69 e5 ff 4b     bl      10eb18 &lt;gaih_inet.constprop.7+0x8&gt;
    1105b4:       78 1b 71 7c     mr      r17,r3
    1105b8:       50 01 7f e8     ld      r3,336(r31)
  ...
  000000000015af20 &lt;inet_pton&gt;:
    15af20:       0b 00 4c 3c     addis   r2,r12,11
    15af24:       e0 c1 42 38     addi    r2,r2,-15904
    15af28:       a6 02 08 7c     mflr    r0
    15af2c:       f0 ff c1 fb     std     r30,-16(r1)
    15af30:       f8 ff e1 fb     std     r31,-8(r1)
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x8
  # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1
  # perf script

Before:

  ping  4507 [002] 514985.546540: probe_libc:inet_pton: (7fffa7dbaf28)
              7fffa7dbaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
              7fffa7d705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 13fb52d70 _init+0xbfc (/usr/bin/ping)
              7fffa7c836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa7c83898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  ping  4507 [002] 514985.546540: probe_libc:inet_pton: (7fffa7dbaf28)
              7fffa7dbaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
              7fffa7d6fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.26.so)
              7fffa7d705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 13fb52d70 _init+0xbfc (/usr/bin/ping)
              7fffa7c836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa7c83898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Case 2 - Attaching a probe at _int_malloc+0x180 (binary offset 0x9cf10).
         Return address in still in LR and a new stack frame has already
         been allocated but not used. The caller's caller, i.e. the third
	 entry, is invalid and should be filtered out and not the second
	 one.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000009cd90 &lt;_int_malloc&gt;:
     9cd90:       17 00 4c 3c     addis   r2,r12,23
     9cd94:       70 a3 42 38     addi    r2,r2,-23696
     9cd98:       26 00 80 7d     mfcr    r12
     9cd9c:       f8 ff e1 fb     std     r31,-8(r1)
     9cda0:       17 00 e4 3b     addi    r31,r4,23
     9cda4:       d8 ff 61 fb     std     r27,-40(r1)
     9cda8:       78 23 9b 7c     mr      r27,r4
     9cdac:       1f 00 bf 2b     cmpldi  cr7,r31,31
     9cdb0:       f0 ff c1 fb     std     r30,-16(r1)
     9cdb4:       b0 ff c1 fa     std     r22,-80(r1)
     9cdb8:       78 1b 7e 7c     mr      r30,r3
     9cdbc:       08 00 81 91     stw     r12,8(r1)
     9cdc0:       11 ff 21 f8     stdu    r1,-240(r1)
     9cdc4:       4c 01 9d 41     bgt     cr7,9cf10 &lt;_int_malloc+0x180&gt;
     9cdc8:       20 00 a4 2b     cmpldi  cr7,r4,32
  ...
     9cf08:       00 00 00 60     nop
     9cf0c:       00 00 42 60     ori     r2,r2,0
     9cf10:       e4 06 ff 7b     rldicr  r31,r31,0,59
     9cf14:       40 f8 a4 7f     cmpld   cr7,r4,r31
     9cf18:       68 05 9d 41     bgt     cr7,9d480 &lt;_int_malloc+0x6f0&gt;
  ...
  000000000009e3c0 &lt;tcache_init.part.4&gt;:
  ...
     9e420:       40 02 80 38     li      r4,576
     9e424:       78 fb e3 7f     mr      r3,r31
     9e428:       71 e9 ff 4b     bl      9cd98 &lt;_int_malloc+0x8&gt;
     9e42c:       00 00 a3 2f     cmpdi   cr7,r3,0
     9e430:       78 1b 7e 7c     mr      r30,r3
  ...
  000000000009f7a0 &lt;__libc_malloc&gt;:
  ...
     9f8f8:       00 00 89 2f     cmpwi   cr7,r9,0
     9f8fc:       1c ff 9e 40     bne     cr7,9f818 &lt;__libc_malloc+0x78&gt;
     9f900:       c9 ea ff 4b     bl      9e3c8 &lt;tcache_init.part.4+0x8&gt;
     9f904:       00 00 00 60     nop
     9f908:       e8 90 22 e9     ld      r9,-28440(r2)
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a _int_malloc+0x180
  # perf record -e probe_libc:_int_malloc -g ./test-malloc
  # perf script

Before:

  test-malloc  6554 [009] 515975.797403: probe_libc:_int_malloc: (7fffa6e6cf10)
              7fffa6e6cf10 _int_malloc+0x180 (/usr/lib64/libc-2.26.so)
              7fffa6dd0000 [unknown] (/usr/lib64/libc-2.26.so)
              7fffa6e6f904 malloc+0x164 (/usr/lib64/libc-2.26.so)
              7fffa6e6f9fc malloc+0x25c (/usr/lib64/libc-2.26.so)
                  100006b4 main+0x38 (/home/testuser/test-malloc)
              7fffa6df36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa6df3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  test-malloc  6554 [009] 515975.797403: probe_libc:_int_malloc: (7fffa6e6cf10)
              7fffa6e6cf10 _int_malloc+0x180 (/usr/lib64/libc-2.26.so)
              7fffa6e6e42c tcache_init.part.4+0x6c (/usr/lib64/libc-2.26.so)
              7fffa6e6f904 malloc+0x164 (/usr/lib64/libc-2.26.so)
              7fffa6e6f9fc malloc+0x25c (/usr/lib64/libc-2.26.so)
                  100006b4 main+0x38 (/home/sandipan/test-malloc)
              7fffa6df36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa6df3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Maynard Johnson &lt;maynard@us.ibm.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Fixes: a60335ba3298 ("perf tools powerpc: Adjust callchain based on DWARF debug info")
Link: http://lkml.kernel.org/r/24bb726d91ed173aebc972ec3f41a2ef2249434e.1530724939.git.sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>perf powerpc: Fix callchain ip filtering when return address is in a register</title>
<updated>2018-09-26T06:39:25Z</updated>
<author>
<name>Sandipan Das</name>
</author>
<published>2018-07-10T13:58:14Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=0c664f04c204b1839b4869d2734e8c964090ef88'/>
<id>urn:sha1:0c664f04c204b1839b4869d2734e8c964090ef88</id>
<content type='text'>
[ Upstream commit 9068533e4f470daf2b0f29c71d865990acd8826e ]

For powerpc64, perf will filter out the second entry in the callchain,
i.e. the LR value, if the return address of the function corresponding
to the probed location has already been saved on its caller's stack.

The state of the return address is determined using debug information.
At any point within a function, if the return address is already saved
somewhere, a DWARF expression can tell us about its location. If the
return address in still in LR only, no DWARF expression would exist.

Typically, the instructions in a function's prologue first copy the LR
value to R0 and then pushes R0 on to the stack. If LR has already been
copied to R0 but R0 is yet to be pushed to the stack, we can still get a
DWARF expression that says that the return address is in R0. This is
indicating that getting a DWARF expression for the return address does
not guarantee the fact that it has already been saved on the stack.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000015af20 &lt;inet_pton&gt;:
    15af20:       0b 00 4c 3c     addis   r2,r12,11
    15af24:       e0 c1 42 38     addi    r2,r2,-15904
    15af28:       a6 02 08 7c     mflr    r0
    15af2c:       f0 ff c1 fb     std     r30,-16(r1)
    15af30:       f8 ff e1 fb     std     r31,-8(r1)
    15af34:       78 1b 7f 7c     mr      r31,r3
    15af38:       78 23 83 7c     mr      r3,r4
    15af3c:       78 2b be 7c     mr      r30,r5
    15af40:       10 00 01 f8     std     r0,16(r1)
    15af44:       c1 ff 21 f8     stdu    r1,-64(r1)
    15af48:       28 00 81 f8     std     r4,40(r1)
  ...

  # readelf --debug-dump=frames-interp /usr/lib64/libc-2.26.so | less
  ...
  00027024 0000000000000024 00027028 FDE cie=00000000 pc=000000000015af20..000000000015af88
     LOC           CFA      r30   r31   ra
  000000000015af20 r1+0     u     u     u
  000000000015af34 r1+0     c-16  c-8   r0
  000000000015af48 r1+64    c-16  c-8   c+16
  000000000015af5c r1+0     c-16  c-8   c+16
  000000000015af78 r1+0     u     u
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x18
  # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1
  # perf script

Before:

  ping  2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38)
              7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so)
              7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 12f152d70 _init+0xbfc (/usr/bin/ping)
              7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  ping  2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38)
              7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so)
              7fff7e26fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.26.so)
              7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 12f152d70 _init+0xbfc (/usr/bin/ping)
              7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Reported-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Maynard Johnson &lt;maynard@us.ibm.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Link: http://lkml.kernel.org/r/66e848a7bdf2d43b39210a705ff6d828a0865661.1530724939.git.sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>perf probe powerpc: Fix trace event post-processing</title>
<updated>2018-09-15T07:46:51Z</updated>
<author>
<name>Sandipan Das</name>
</author>
<published>2018-08-09T16:19:29Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=c728031a35356c5c76be8b908f502384e225b18c'/>
<id>urn:sha1:c728031a35356c5c76be8b908f502384e225b18c</id>
<content type='text'>
[ Upstream commit 354b064b8ebc1e1ede58550ca9e08bfa81e6af43 ]

In some cases, a symbol may have multiple aliases. Attempting to add an
entry probe for such symbols results in a probe being added at an
incorrect location while it fails altogether for return probes. This is
only applicable for binaries with debug information.

During the arch-dependent post-processing, the offset from the start of
the symbol at which the probe is to be attached is determined and added
to the start address of the symbol to get the probe's location.  In case
there are multiple aliases, this offset gets added multiple times for
each alias of the symbol and we end up with an incorrect probe location.

This can be verified on a powerpc64le system as shown below.

  $ nm /lib/modules/$(uname -r)/build/vmlinux | grep "sys_open$"
  ...
  c000000000414290 T __se_sys_open
  c000000000414290 T sys_open

  $ objdump -d /lib/modules/$(uname -r)/build/vmlinux | grep -A 10 "&lt;__se_sys_open&gt;:"

  c000000000414290 &lt;__se_sys_open&gt;:
  c000000000414290:       19 01 4c 3c     addis   r2,r12,281
  c000000000414294:       70 c4 42 38     addi    r2,r2,-15248
  c000000000414298:       a6 02 08 7c     mflr    r0
  c00000000041429c:       e8 ff a1 fb     std     r29,-24(r1)
  c0000000004142a0:       f0 ff c1 fb     std     r30,-16(r1)
  c0000000004142a4:       f8 ff e1 fb     std     r31,-8(r1)
  c0000000004142a8:       10 00 01 f8     std     r0,16(r1)
  c0000000004142ac:       c1 ff 21 f8     stdu    r1,-64(r1)
  c0000000004142b0:       78 23 9f 7c     mr      r31,r4
  c0000000004142b4:       78 1b 7e 7c     mr      r30,r3

  For both the entry probe and the return probe, the probe location
  should be _text+4276888 (0xc000000000414298). Since another alias
  exists for 'sys_open', the post-processing code will end up adding
  the offset (8 for powerpc64le) twice and perf will attempt to add
  the probe at _text+4276896 (0xc0000000004142a0) instead.

Before:

  # perf probe -v -a sys_open

  probe-definition(0): sys_open
  symbol:sys_open file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /lib/modules/4.18.0-rc8+/build/vmlinux for symbols
  Open Debuginfo file: /lib/modules/4.18.0-rc8+/build/vmlinux
  Try to find probe point from debuginfo.
  Symbol sys_open address found : c000000000414290
  Matched function: __se_sys_open [2ad03a0]
  Probe point found: __se_sys_open+0
  Found 1 probe_trace_events.
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Writing event: p:probe/sys_open _text+4276896
  Added new event:
    probe:sys_open       (on sys_open)
  ...

  # perf probe -v -a sys_open%return $retval

  probe-definition(0): sys_open%return
  symbol:sys_open file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /lib/modules/4.18.0-rc8+/build/vmlinux for symbols
  Open Debuginfo file: /lib/modules/4.18.0-rc8+/build/vmlinux
  Try to find probe point from debuginfo.
  Symbol sys_open address found : c000000000414290
  Matched function: __se_sys_open [2ad03a0]
  Probe point found: __se_sys_open+0
  Found 1 probe_trace_events.
  Opening /sys/kernel/debug/tracing/README write=0
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Parsing probe_events: p:probe/sys_open _text+4276896
  Group:probe Event:sys_open probe:p
  Writing event: r:probe/sys_open__return _text+4276896
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)

After:

  # perf probe -v -a sys_open

  probe-definition(0): sys_open
  symbol:sys_open file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /lib/modules/4.18.0-rc8+/build/vmlinux for symbols
  Open Debuginfo file: /lib/modules/4.18.0-rc8+/build/vmlinux
  Try to find probe point from debuginfo.
  Symbol sys_open address found : c000000000414290
  Matched function: __se_sys_open [2ad03a0]
  Probe point found: __se_sys_open+0
  Found 1 probe_trace_events.
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Writing event: p:probe/sys_open _text+4276888
  Added new event:
    probe:sys_open       (on sys_open)
  ...

  # perf probe -v -a sys_open%return $retval

  probe-definition(0): sys_open%return
  symbol:sys_open file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /lib/modules/4.18.0-rc8+/build/vmlinux for symbols
  Open Debuginfo file: /lib/modules/4.18.0-rc8+/build/vmlinux
  Try to find probe point from debuginfo.
  Symbol sys_open address found : c000000000414290
  Matched function: __se_sys_open [2ad03a0]
  Probe point found: __se_sys_open+0
  Found 1 probe_trace_events.
  Opening /sys/kernel/debug/tracing/README write=0
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Parsing probe_events: p:probe/sys_open _text+4276888
  Group:probe Event:sys_open probe:p
  Writing event: r:probe/sys_open__return _text+4276888
  Added new event:
    probe:sys_open__return (on sys_open%return)
  ...

Reported-by: Aneesh Kumar &lt;aneesh.kumar@linux.vnet.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Acked-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Aneesh Kumar &lt;aneesh.kumar@linux.vnet.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Fixes: 99e608b5954c ("perf probe ppc64le: Fix probe location when using DWARF")
Link: http://lkml.kernel.org/r/20180809161929.35058-1-sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>perf report powerpc: Fix crash if callchain is empty</title>
<updated>2018-06-25T14:59:35Z</updated>
<author>
<name>Sandipan Das</name>
</author>
<published>2018-06-11T10:40:49Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=143c99f6ac6812d23254e80844d6e34be897d3e1'/>
<id>urn:sha1:143c99f6ac6812d23254e80844d6e34be897d3e1</id>
<content type='text'>
For some cases, the callchain provided by the kernel may be empty. So,
the callchain ip filtering code will cause a crash if we do not check
whether the struct ip_callchain pointer is NULL before accessing any
members.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

  # perf record -b -e cycles:u ls

Before:

  # perf report --branch-history

  perf: Segmentation fault
  -------- backtrace --------
  perf[0x1027615c]
  linux-vdso64.so.1(__kernel_sigtramp_rt64+0x0)[0x7fff856304d8]
  perf(arch_skip_callchain_idx+0x44)[0x10257c58]
  perf[0x1017f2e4]
  perf(thread__resolve_callchain+0x124)[0x1017ff5c]
  perf(sample__resolve_callchain+0xf0)[0x10172788]
  ...

After:

  # perf report --branch-history

  Samples: 25  of event 'cycles:u', Event count (approx.): 2306870
    Overhead  Source:Line            Symbol                   Shared Object
  +   11.60%  _init+35736            [.] _init                ls
  +    9.84%  strcoll_l.c:137        [.] __strcoll_l          libc-2.26.so
  +    9.16%  memcpy.S:175           [.] __memcpy_power7      libc-2.26.so
  +    9.01%  gconv_charset.h:54     [.] _nl_find_locale      libc-2.26.so
  +    8.87%  dl-addr.c:52           [.] _dl_addr             libc-2.26.so
  +    8.83%  _init+236              [.] _init                ls
  ...

Reported-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Acked-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Link: http://lkml.kernel.org/r/20180611104049.11048-1-sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf map: Remove map_type arg from map_groups__find()</title>
<updated>2018-04-26T16:47:18Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
</author>
<published>2018-04-26T12:49:31Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=e1f2a0d0f2d80c7fedb5f910367bc12d02e914a7'/>
<id>urn:sha1:e1f2a0d0f2d80c7fedb5f910367bc12d02e914a7</id>
<content type='text'>
One more step in ditching the split.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-4pour7egur07tkrpbynawemv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf map: Shorten map_groups__find() signature</title>
<updated>2018-04-26T16:47:12Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
</author>
<published>2018-04-25T15:39:22Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=abe5449d2de6ccc58444451b6fed130100892097'/>
<id>urn:sha1:abe5449d2de6ccc58444451b6fed130100892097</id>
<content type='text'>
Removing the map_type, that is going away.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-18iiiw25r75xn7zlppjldk48@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf thread: Introduce thread__find_symbol()</title>
<updated>2018-04-26T16:47:07Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
</author>
<published>2018-04-24T14:24:49Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=4546263d72e22ea84b49dafad26d8ca679d5e83d'/>
<id>urn:sha1:4546263d72e22ea84b49dafad26d8ca679d5e83d</id>
<content type='text'>
Out of thread__find_addr_location(..., MAP__FUNCTION, ...), idea here is to
continue removing references to MAP__{FUNCTION,VARIABLE} ahead of
getting both types of symbols in the same rbtree, as various places do
two lookups, looking first at MAP__FUNCTION, then at MAP__VARIABLE.

So thread__find_symbol() will eventually do just that, and 'struct
symbol' will have the symbol type, for code that cares about that.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-n7528en9e08yd3flzmb26tth@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf powerpc: Generate system call table from asm/unistd.h</title>
<updated>2018-02-16T17:55:48Z</updated>
<author>
<name>Ravi Bangoria</name>
</author>
<published>2018-01-29T08:34:16Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=8e2ff72aa35e1a8a53894ae46751a83543338e14'/>
<id>urn:sha1:8e2ff72aa35e1a8a53894ae46751a83543338e14</id>
<content type='text'>
This should speed up accessing new system calls introduced with the
kernel rather than waiting for libaudit updates to include them.

Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Thomas Richter &lt;tmricht@linux.vnet.ibm.com&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20180129083417.31240-3-ravi.bangoria@linux.vnet.ibm.com
[ Made it generate syscall_32.c as well to fix the build on 32-bit ppc ]
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf probe: Find versioned symbols from map</title>
<updated>2017-12-27T15:15:54Z</updated>
<author>
<name>Masami Hiramatsu</name>
</author>
<published>2017-12-08T16:28:12Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=4b3a2716dd785fabb9f6ac80c1d53cb29a88169d'/>
<id>urn:sha1:4b3a2716dd785fabb9f6ac80c1d53cb29a88169d</id>
<content type='text'>
Commit d80406453ad4 ("perf symbols: Allow user probes on versioned
symbols") allows user to find default versioned symbols (with "@@") in
map. However, it did not enable normal versioned symbol (with "@") for
perf-probe.  E.g.

  =====
  # ./perf probe -x /lib64/libc-2.25.so malloc_get_state
  Failed to find symbol malloc_get_state in /usr/lib64/libc-2.25.so
    Error: Failed to add events.
  =====

This solves above issue by improving perf-probe symbol search function,
as below.

  =====
  # ./perf probe -x /lib64/libc-2.25.so malloc_get_state
  Added new event:
    probe_libc:malloc_get_state (on malloc_get_state in /usr/lib64/libc-2.25.so)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libc:malloc_get_state -aR sleep 1

  # ./perf probe -l
    probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so)
  =====

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Reviewed-by: Thomas Richter &lt;tmricht@linux.vnet.ibm.com&gt;
Acked-by: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Paul Clarke &lt;pc@us.ibm.com&gt;
Cc: bhargavb &lt;bhargavaramudu@gmail.com&gt;
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/151275049269.24652.1639103455496216255.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
</feed>
