issue-437 Fixed issues related to new glibc shipped with Ubuntu 10.10

1. ptrace permissions were modifed to be a bit more strict which required
   us to programatically set the permissions while syncing up to the profiling
   thread.

2. Order of destructors registered with atexit changed which was casuing us to
   miss generating the backtrace when heap checker was finished. Seems that we
   initially fixed this for FreeBSD and now linux has changed their behaviour
   to be the same. We are now a bit stricter on the rules here accross all
   platforms.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@152 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-453 Added support to get the timebase register value using just one instruction and also adjusts the PPC32 code to the recent GLIBC one that implements the same functionality

git-svn-id: https://gperftools.googlecode.com/svn/trunk@153 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-457: Fixed an issue where the 'getpc' testcase was using the wrong PPC64 preprocessor directive

git-svn-id: https://gperftools.googlecode.com/svn/trunk@154 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-455: Adds another size for large pages in tcmalloc through the new define TCMALLOC_LARGE_PAGES64K

git-svn-id: https://gperftools.googlecode.com/svn/trunk@155 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-456: Adds support for CACHELINE_ALIGNED values for PPC

git-svn-id: https://gperftools.googlecode.com/svn/trunk@156 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-458: Optimizes malloc hooks for weakly consistent memory architectures

git-svn-id: https://gperftools.googlecode.com/svn/trunk@157 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-446: Fixes compatability issues in malloc_hook_test for PPC64

git-svn-id: https://gperftools.googlecode.com/svn/trunk@158 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
Adding support for CPU frequencies for Linux on PowerPC

git-svn-id: https://gperftools.googlecode.com/svn/trunk@159 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-442: Fixes an issue encountered on PPC with undefined conversions from 'base::subtle::Atomic64*' to 'const volatile Atomic32*'

git-svn-id: https://gperftools.googlecode.com/svn/trunk@160 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-405: backed out original commit made in revision 147 due to the fact that it didn't work as intended

git-svn-id: https://gperftools.googlecode.com/svn/trunk@161 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-411: This commit adds additional logging to the cpu profiler to warn when the profiler is run and no CPUPROFILE environment setting can be found. It also adds a new environment variable PERFTOOLS_UNITTEST to allow certain modules to take action when running under the umbrella of a unit test.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@162 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-417: This commit removed the fatal error message printed along with the pprof usage information when pprof is run with no arguments.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@163 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-424: Updated heap profiler documentation that had mispelling for the heap profiler mmap only environment setting (HEAP_PROFILE_ONLY_MMAP)

git-svn-id: https://gperftools.googlecode.com/svn/trunk@164 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-480: duplicate of issue-385 fixed in r150 however some of the comments in the code
regarding frame pointers needed to be clarified.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@165 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
amend-r165: forgot to regenrate configure and Makefile.in

git-svn-id: https://gperftools.googlecode.com/svn/trunk@166 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-481: Replaced test mechanism for distinct address spaces with a more reliable mechanism

Rather than using sys_ptrace+PTRACE_PEEK_DATA to determine whether address spaces are distinct, we now use sys_waitpid+__WCLONE. See issue-481 for a more detailed rationale.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@167 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-479: Replaced sscanf usage while iterating proc maps entries to fix a deadlock introduced by glibc-2.15.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@168 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-478: Added the heap profiler tunnable setting HEAP_PROFILER_TIME_INTERVAL used to dump heap profiles on a specified time interval.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@169 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-477: Fix clang compilation errors regarding format specifiers

git-svn-id: https://gperftools.googlecode.com/svn/trunk@170 6b5cf1ce-ec42-a296-1ba9-69fdba395a50
issue-476: Amendment to r152:issue-437 to fix a build error due to PR_SET_TRACER not being defined in older glibc releases.

git-svn-id: https://gperftools.googlecode.com/svn/trunk@171 6b5cf1ce-ec42-a296-1ba9-69fdba395a50