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@@ -100,8 +100,8 @@ Using perf to do Basic Profiling
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As a simple test case, we'll profile the 'wget' of a fairly large file,
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which is a minimally interesting case because it has both file and
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network I/O aspects, and at least in the case of standard Yocto images,
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-it's implemented as part of busybox, so the methods we use to analyze it
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-can be used in a very similar way to the whole host of supported busybox
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+it's implemented as part of BusyBox, so the methods we use to analyze it
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+can be used in a very similar way to the whole host of supported BusyBox
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applets in Yocto. ::
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root@crownbay:~# rm linux-2.6.19.2.tar.bz2; \
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@@ -251,7 +251,7 @@ As a bit of background explanation for these callchains, think about
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what happens at a high level when you run wget to get a file out on the
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network. Basically what happens is that the data comes into the kernel
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via the network connection (socket) and is passed to the userspace
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-program 'wget' (which is actually a part of busybox, but that's not
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+program 'wget' (which is actually a part of BusyBox, but that's not
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important for now), which takes the buffers the kernel passes to it and
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writes it to a disk file to save it.
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@@ -277,16 +277,16 @@ Now that we've seen the basic layout of the profile data and the basics
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of how to extract useful information out of it, let's get back to the
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task at hand and see if we can get some basic idea about where the time
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is spent in the program we're profiling, wget. Remember that wget is
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-actually implemented as an applet in busybox, so while the process name
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-is 'wget', the executable we're actually interested in is busybox. So
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-let's expand the first entry containing busybox:
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+actually implemented as an applet in BusyBox, so while the process name
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+is 'wget', the executable we're actually interested in is BusyBox. So
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+let's expand the first entry containing BusyBox:
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.. image:: figures/perf-wget-busybox-expanded-stripped.png
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:align: center
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Again, before we expanded we saw that the function was labeled with a
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hex value instead of a symbol as with most of the kernel entries.
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-Expanding the busybox entry doesn't make it any better.
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+Expanding the BusyBox entry doesn't make it any better.
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The problem is that perf can't find the symbol information for the
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busybox binary, which is actually stripped out by the Yocto build
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@@ -299,7 +299,7 @@ when you build the image: ::
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However, we already have an image with the binaries stripped, so
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what can we do to get perf to resolve the symbols? Basically we need to
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-install the debuginfo for the busybox package.
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+install the debuginfo for the BusyBox package.
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To generate the debug info for the packages in the image, we can add
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``dbg-pkgs`` to :term:`EXTRA_IMAGE_FEATURES` in ``local.conf``. For example: ::
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@@ -314,7 +314,7 @@ in the ``local.conf`` file: ::
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PACKAGE_DEBUG_SPLIT_STYLE = 'debug-file-directory'
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Once we've done that, we can install the
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-debuginfo for busybox. The debug packages once built can be found in
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+debuginfo for BusyBox. The debug packages once built can be found in
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``build/tmp/deploy/rpm/*`` on the host system. Find the busybox-dbg-...rpm
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file and copy it to the target. For example: ::
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@@ -325,7 +325,7 @@ Now install the debug rpm on the target: ::
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root@crownbay:~# rpm -i busybox-dbg-1.20.2-r2.core2_32.rpm
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-Now that the debuginfo is installed, we see that the busybox entries now display
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+Now that the debuginfo is installed, we see that the BusyBox entries now display
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their functions symbolically:
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.. image:: figures/perf-wget-busybox-debuginfo.png
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@@ -345,11 +345,11 @@ expanded all the nodes using the 'E' key):
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.. image:: figures/perf-wget-busybox-dso-zoom.png
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:align: center
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-Finally, we can see that now that the busybox debuginfo is installed,
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+Finally, we can see that now that the BusyBox debuginfo is installed,
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the previously unresolved symbol in the ``sys_clock_gettime()`` entry
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mentioned previously is now resolved, and shows that the
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sys_clock_gettime system call that was the source of 6.75% of the
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-copy-to-user overhead was initiated by the ``handle_input()`` busybox
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+copy-to-user overhead was initiated by the ``handle_input()`` BusyBox
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function:
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.. image:: figures/perf-wget-g-copy-to-user-expanded-debuginfo.png
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@@ -1900,7 +1900,7 @@ the target: ::
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meta-toolchain
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meta-ide-support
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- You can also run generated qemu images with a command like 'runqemu qemux86-64'
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+ You can also run generated QEMU images with a command like 'runqemu qemux86-64'
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Once you've done that, you can cd to whatever
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directory contains your scripts and use 'crosstap' to run the script: ::
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Michael Opdenacker