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6 commits

Author SHA1 Message Date
Christopher Ferris
602b88ccdd Provide method to dump backtrace heap data.
For non-zygote spawned processes, we might want to dump the backtrace
data. Provide a method to send a signal to a process and then dump the
data to a file.

Adds a method to dump the backtrace data on exit.

Update documentation and explain format of heap dump data.

Test: Ran unit tests, enabled new options and used them.
Change-Id: Ie2fa706694160731afe02c1382b037d06df1d069
2017-09-05 15:57:00 -07:00
Christopher Ferris
2b2b25b878 Refactor Config from a struct to a class.
This should make it easier to add new options, and to add options that
are complex. For example, I want to modify the behavior of
record_allocs_file so that it also enables record_allocs to a default
state.

Test: All unit tests pass.
Test: Enable the backtrace option and restart.
Change-Id: Idf5cdeed06ade3bc2c8ae39d228734bf65209b4f
2017-04-06 15:30:42 -07:00
Christopher Ferris
426b00a29b Fix the way malloc debug returns info.
When I rewrote malloc debug, I accidentally thought that each
value returned in the info buffer contained the number of backtrace
frames in the backtrace. This was incorrect, it should have been
the total number of allocations with the same backtrace.

This is a temporary fix that sets that value to 1. The better fix is
to de-dupe backtraces and then return all allocations of the same size
with the same backtrace.

I updated the documents to describe this.

Bug: 31854476

Test: Unit tests pass.
Change-Id: Idf9efaa3d363923b5d7543d90dc7c65a0ed553d9
2017-03-09 13:47:37 -08:00
Christopher Ferris
55a89a48f4 Small refactor.
- Move all ScopedDisableDebugCalls into the debug_XXX calls. This avoids
any issues that might arise where every part of the code needs to properly
guard anything that might allocate. Instead everything is already guarded.
- Add a pointer to debug_data in all of the XXData classes. This avoids
calling individual functions passing in the debug_data pointer.
- Flip the NO_HEADER_OPTIONS to an explicit HEADER_OPTIONS list since fewer
options actually require a header.
- Move the extern of g_debug to the DebugData.h header.

Change-Id: Ia213a391b4a44d9ce122a709d09fe4f1b5426f36
2016-04-12 15:36:53 -07:00
Colin Cross
869691c6f7 Export malloc_iterate and friends
Export malloc_iterate, malloc_enable, and malloc_disable to be used by
libmemunreachable.

Change-Id: I08a50349af82a95d096b6b4cbac37ababe4b9b06
2016-02-18 15:05:38 -08:00
Christopher Ferris
63860cb8fd Malloc debug rewrite.
The major components of the rewrite:

- Completely remove the qemu shared library code. Nobody was using it
  and it appears to have broken at some point.
- Adds the ability to enable/disable different options independently.
- Adds a new option that can enable the backtrace on alloc/free when
  a process gets a specific signal.
- Adds a new way to enable malloc debug. If a special property is
  set, and the process has an environment variable set, then debug
  malloc will be enabled. This allows something that might be
  a derivative of app_process to be started with an environment variable
  being enabled.
- get_malloc_leak_info() used to return one element for each pointer that
  had the exact same backtrace. The new version returns information for
  every one of the pointers with same backtrace. It turns out ddms already
  automatically coalesces these, so the old method simply hid the fact
  that there where multiple pointers with the same amount of backtrace.
- Moved all of the malloc debug specific code into the library.
  Nothing related to the malloc debug data structures remains in libc.
- Removed the calls to the debug malloc cleanup routine. Instead, I
  added an atexit call with the debug malloc cleanup routine. This gets
  around most problems related to the timing of doing the cleanup.

The new properties and environment variables:

libc.debug.malloc.options
  Set by option name (such as "backtrace"). Setting this to a bad value
  will cause a usage statement to be printed to the log.

libc.debug.malloc.program
  Same as before. If this is set, then only the program named will
  be launched with malloc debug enabled. This is not a complete match,
  but if any part of the property is in the program name, malloc debug is
  enabled.

libc.debug.malloc.env_enabled
  If set, then malloc debug is only enabled if the running process has the
  environment variable LIBC_DEBUG_MALLOC_ENABLE set.

Bug: 19145921

Change-Id: I7b0e58cc85cc6d4118173fe1f8627a391b64c0d7
2016-01-25 10:54:21 -08:00