How to compile perf for Android
=========================================

I. Set the Android NDK environment
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(a). Use the Android NDK
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1. You need to download and install the Android Native Development Kit (NDK).
Set the NDK variable to point to the path where you installed the NDK:
  export NDK=/path/to/android-ndk

2. Set cross-compiling environment variables for NDK toolchain and sysroot.
For arm:
  export NDK_TOOLCHAIN=${NDK}/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-
  export NDK_SYSROOT=${NDK}/platforms/android-24/arch-arm
For x86:
  export NDK_TOOLCHAIN=${NDK}/toolchains/x86-4.9/prebuilt/linux-x86_64/bin/i686-linux-android-
  export NDK_SYSROOT=${NDK}/platforms/android-24/arch-x86

This method is only tested for Android NDK versions Revision 11b and later.
perf uses some bionic enhancements that are not included in prior NDK versions.
You can use method (b) described below instead.

(b). Use the Android source tree
-----------------------------------------------
1. Download the master branch of the Android source tree.
Set the environment for the target you want using:
  source build/envsetup.sh
  lunch

2. Build your own NDK sysroot to contain latest bionic changes and set the
NDK sysroot environment variable.
  cd ${ANDROID_BUILD_TOP}/ndk
For arm:
  ./build/tools/build-ndk-sysroot.sh --abi=arm
  export NDK_SYSROOT=${ANDROID_BUILD_TOP}/ndk/build/platforms/android-3/arch-arm
For x86:
  ./build/tools/build-ndk-sysroot.sh --abi=x86
  export NDK_SYSROOT=${ANDROID_BUILD_TOP}/ndk/build/platforms/android-3/arch-x86

3. Set the NDK toolchain environment variable.
For arm:
  export NDK_TOOLCHAIN=${ANDROID_TOOLCHAIN}/arm-linux-androideabi-
For x86:
  export NDK_TOOLCHAIN=${ANDROID_TOOLCHAIN}/i686-linux-android-

II. Compile perf for Android
------------------------------------------------
You need to run make with the NDK toolchain and sysroot defined above:
For arm:
  make WERROR=0 ARCH=arm CROSS_COMPILE=${NDK_TOOLCHAIN} EXTRA_CFLAGS="-pie --sysroot=${NDK_SYSROOT}"
For x86:
  make WERROR=0 ARCH=x86 CROSS_COMPILE=${NDK_TOOLCHAIN} EXTRA_CFLAGS="-pie --sysroot=${NDK_SYSROOT}"

III. Install perf
-----------------------------------------------
You need to connect to your Android device/emulator using adb.
Install perf using:
  adb push perf /data/perf

If you also want to use perf-archive you need busybox tools for Android.
For installing perf-archive, you first need to replace #!/bin/bash with #!/system/bin/sh:
  sed 's/#!\/bin\/bash/#!\/system\/bin\/sh/g' perf-archive >> /tmp/perf-archive
  chmod +x /tmp/perf-archive
  adb push /tmp/perf-archive /data/perf-archive

IV. Environment settings for running perf
------------------------------------------------
Some perf features need environment variables to run properly.
You need to set these before running perf on the target:
  adb shell
  # PERF_PAGER=cat

IV. Run perf
------------------------------------------------
Run perf on your device/emulator to which you previously connected using adb:
  # ./data/perf
class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-15 16:09:50 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-15 16:09:50 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc?id=99421c1cb27fb837e93b517036fab4500fe39de5'>99421c1cb27fb837e93b517036fab4500fe39de5</a> (<a href='/cgit.cgi/linux/net-next.git/patch/sound/soc?id=99421c1cb27fb837e93b517036fab4500fe39de5'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=99421c1cb27fb837e93b517036fab4500fe39de5'>de5fc5bacb671223f389793ad643cebe520bc292</a> /<a href='/cgit.cgi/linux/net-next.git/tree/sound/soc?id=99421c1cb27fb837e93b517036fab4500fe39de5'>sound/soc</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc?id=c92816275674c1491ce228ee49aa030a5fa1be04'>c92816275674c1491ce228ee49aa030a5fa1be04</a> (<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc?id=99421c1cb27fb837e93b517036fab4500fe39de5&amp;id2=c92816275674c1491ce228ee49aa030a5fa1be04'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc?id=93362fa47fe98b62e4a34ab408c4a418432e7939'>93362fa47fe98b62e4a34ab408c4a418432e7939</a> (<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc?id=99421c1cb27fb837e93b517036fab4500fe39de5&amp;id2=93362fa47fe98b62e4a34ab408c4a418432e7939'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</div><div class='commit-msg'>Pull namespace fixes from Eric Biederman:
 "This tree contains 4 fixes.

  The first is a fix for a race that can causes oopses under the right
  circumstances, and that someone just recently encountered.

  Past that are several small trivial correct fixes. A real issue that
  was blocking development of an out of tree driver, but does not appear
  to have caused any actual problems for in-tree code. A potential
  deadlock that was reported by lockdep. And a deadlock people have
  experienced and took the time to track down caused by a cleanup that
  removed the code to drop a reference count"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sysctl: Drop reference added by grab_header in proc_sys_readdir
  pid: fix lockdep deadlock warning due to ucount_lock
  libfs: Modify mount_pseudo_xattr to be clear it is not a userspace mount
  mnt: Protect the mountpoint hashtable with mount_lock
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=99421c1cb27fb837e93b517036fab4500fe39de5'>Diffstat</a> (limited to 'sound/soc')</div><table summary='diffstat' class='diffstat'>