To: perfctr-devel@lists.sourceforge.net
Subject: perfctr-2.6.10-pre1 released

Version 2.6.10-pre1 of perfctr, the Linux performance
monitoring counters driver, is now available at the usual
place: http://www.csd.uu.se/~mikpe/linux/perfctr/2.6/

Intel's 64-bit P4 Xeon should now work in the 64-bit kernel.
Unfortunately this required changing the layout of some data
structures (the structs for control data and counter sums):
they are now identical to those used in 32-bit code.

Binary compatibility for 64-bit code is partially broken:
- existing application code + existing library code + new driver:
  works for K8, but the new Xeon can't be handled by user-space
- recompiled application code + recompiled library + old driver:
  works for K8, but the new Xeon will be detected as a generic
  CPU and its performance counters won't be available
- existing application code + recompiled library code:
  binary incompatible due to struct layout changes
- recompiled application code + existing library code:
  binary incompatible due to struct layout changes

To help avoid application/library mismatches, the shared
library on x86-64 has been given a new major number.

Version 2.6.10-pre1, 2004-08-03
- x86-64 now uses the same driver and data structures as x86.
  Intel's 64-bit P4 Xeon should work in the x86-64 kernel.
  x86-64 application-level data structures have changed.
- Updated library and example applications to include P4
  support on x86-64.
- Fixed update-kernel script to use 'head' in a POSIX
  compliant way.
- Added kernel support for the Model 13 Pentium-M.
- Many code cleanups in the x86 driver.
- Event 0x76 is now officially CPU_CLK_UNHALTED on AMD64.
- Updated kernel support: 2.4.27-rc4.

/ Mikael Pettersson