Jiri Olsa bb91a073ed perf tools: Allow to build with -ltcmalloc
By using "make TCMALLOC=1" you can enable perf to be build for usage
with libtcmalloc.so (gperftools).

Get heap profile (tools/perf directory):

  $ <install gperftools>
  $ make TCMALLOC=1 DEBUG=1
  $ HEAPPROFILE=/tmp/heapprof ./perf ...
  $ pprof ./perf /tmp/heapprof.000*
  (pprof) top
  Total: 2335.5 MB
    1735.1  74.3%  74.3%   1735.1  74.3% memdup
     402.0  17.2%  91.5%    402.0  17.2% zalloc
     140.2   6.0%  97.5%    145.8   6.2% map__new
      33.6   1.4%  98.9%     33.6   1.4% symbol__new
      12.4   0.5%  99.5%     12.4   0.5% alloc_event
       6.2   0.3%  99.7%      6.2   0.3% nsinfo__new
       5.5   0.2% 100.0%      5.5   0.2% nsinfo__copy
       0.3   0.0% 100.0%      0.3   0.0% dso__new
       0.1   0.0% 100.0%      0.1   0.0% do_read_string
       0.0   0.0% 100.0%      0.0   0.0% __GI__IO_file_doallocate

See callstack:
  $ pprof --pdf ./perf /tmp/heapprof.00* > callstack.pdf
  $ pprof --web ./perf /tmp/heapprof.00*

Committer testing:

Install gperftools, on fedora:

  # dnf install gperftools-devel

Then build:

 $ make TCMALLOC=1 DEBUG=1 -C tools/perf O=/tmp/build/perf install-bin

Verify that it linked against the right library:

  $ ldd ~/bin/perf | grep tcma
	libtcmalloc.so.4 => /lib64/libtcmalloc.so.4 (0x00007fb2953a7000)
  $

Run 'perf trace' system wide for 1 minute:

  # HEAPPROFILE=/tmp/heapprof perf trace -a sleep 1m
  <SNIP>
   59985.524 ( 0.006 ms): Web Content/20354 recvmsg(fd: 9<socket:[1762817]>, msg: 0x7ffee5fdafb0) = -1 EAGAIN (Resource temporarily unavailable)
   59985.536 ( 0.005 ms): Web Content/20354 recvmsg(fd: 9<socket:[1762817]>, msg: 0x7ffee5fdafc0) = -1 EAGAIN (Resource temporarily unavailable)
   59981.956 (10.143 ms): SCTP timer/21716  ... [continued]: select())                            = 0 (Timeout)
   59985.549 (         ): Web Content/20354 poll(ufds: 0x7f1df38af180, nfds: 3, timeout_msecs: 4294967295) ...
       0.926 (59999.481 ms): sleep/29764  ... [continued]: nanosleep())                           = 0
   59992.133 (         ): SCTP timer/21716 select(tvp: 0x7ff5bf7fee80)                            ...
   60000.477 ( 0.009 ms): sleep/29764 close(fd: 1)                                                = 0
   60000.493 ( 0.005 ms): sleep/29764 close(fd: 2)                                                = 0
   60000.514 (         ): sleep/29764 exit_group()                                                = ?
  Dumping heap profile to /tmp/heapprof.0001.heap (Exiting, 3 MB in use)
[root@quaco ~]#

Install pprof:

  # dnf install pprof

And run it:

  # pprof ~/bin/perf /tmp/heapprof.0001.heap
  Using local file /root/bin/perf.
  Using local file /tmp/heapprof.0001.heap.
  Welcome to pprof!  For help, type 'help'.
  (pprof) top
  Total: 4.0 MB
       1.7  42.0%  42.0%      2.2  54.1% map__new
       0.9  23.3%  65.3%      0.9  23.3% zalloc
       0.5  11.4%  76.7%      0.5  11.4% dso__new
       0.2   5.6%  82.3%      0.3   8.5% trace__sys_enter
       0.2   4.9%  87.2%      0.2   4.9% __GI___strdup
       0.2   3.8%  91.0%      0.2   3.8% new_term
       0.1   2.2%  93.2%      0.4  10.1% __perf_pmu__new_alias
       0.0   1.0%  94.3%      0.0   1.2% event_read_fields
       0.0   0.8%  95.1%      0.0   0.8% nsinfo__new
       0.0   0.7%  95.8%      0.1   3.2% trace__read_syscall_info
  (pprof)

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20191013151427.11941-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-10-15 08:36:22 -03:00
2019-10-12 15:37:12 -07:00
2019-10-13 08:40:31 -07:00
2019-10-13 08:40:31 -07:00
2019-10-13 14:47:10 -07:00
2019-10-13 08:40:31 -07:00
2019-10-13 14:47:10 -07:00
2019-10-11 08:45:32 -07:00
2019-10-11 14:28:59 -07:00
2019-10-13 14:47:10 -07:00
2019-10-08 10:51:37 -07:00
2019-09-24 16:46:16 -07:00
2019-10-03 12:08:50 +02:00
2019-09-22 10:34:46 -07:00
2019-10-15 07:19:55 +02:00
2019-10-13 16:37:36 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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