Subject: [Announce] Version 1.5 of x86 performance counters driver

Version 1.5 of my x86 performance-monitoring counters driver is
now available at http://www.csd.uu.se/~mikpe/linux/perfctr/.

Summary of changes since version 1.4:
- The virtual perfctr "remote control" facility has been removed,
  resulting in major simplifications in the driver.
  Since version 1.3 of the driver, the most common application of
  the remote control facility (to record events from unmodified
  applications) can be more easily implemented using the perfctr
  inheritance facility (perfctr control setup is inherited from parent
  to child processes, and a child's event counts are propagated back
  to its parent). Removing the remote control facility simplified
  resource management and eliminated a number of concurrency issues.
- Code cleanups. Dropped support for intermediate 2.3 and early 2.4
  kernels. The code now supports kernels 2.2.xx and 2.4.0-test7 or
  later only (via a 2.4-on-2.2 simulation layer).
- A number of changes to the user-space library. The API is now thread-
  safe (the library has no internal state), and the naming scheme has
  been simplified due to the removal of the remote-control facility.
  The zero-syscall perfctr sampling code has been rewritten and should
  be faster and more robust. (It fixed a sampling problem one user had
  on a 4-way MP box.)


/ Mikael Pettersson