Change Details

A test program, along with a test kernel module, can be found at: https://people.freebsd.org/~luporl/sptest (The Makefile assumes host is an amd64 machine with a cross powerpc64 toolchain installed, although it should be easy to port it build natively) With the compiled program and module at current directory, running `./test all` runs all test cases, that exercises most superpage operations, such as: - promotion - demotion - enter - removal - unwire - protect - etc The test program should be run in single user mode, to avoid interference from other processes. Also, most test cases expect a file called "mmap" in the current directory, with a size of exactly 16MB. To create it, run `dd if=/dev/zero of=mmap bs=1m count=16`. Besides the test program, `stress` was used to simulate high memory usage, exercise swap and better test SP REF/CHG bits handling. The tests above were run both on a QEMU VM, with KVM enabled, and also directly on a POWER8 machine. Finally, buildworld was run with superpages enabled (results above) and no stabilty issues were noticed.

A test program, along with a test kernel module, can be found at: https://people.freebsd.org/~luporl/sptest (The Makefile assumes host is an amd64 machine with a cross powerpc64 toolchain installed, although it should be easy to port it build natively) With the compiled program and module at current directory, running `./test all` runs all test cases, that exercises most superpage operations, such as: - promotion - demotion - enter - removal - unwire - protect - etc The test program should be run in single user mode, to avoid interference from other processes. Also, most test cases expect a file called "mmap" in the current directory, with a size of exactly 16MB. To create it, run `dd if=/dev/zero of=mmap bs=1m count=16`. Besides the test program, `stress` was used to simulate high memory usage, exercise swap and better test SP REF/CHG bits handling. The tests above were run both on a QEMU VM, with KVM enabled, and also directly on a POWER8 (previous patch version) and a POWER9 machine. Finally, buildworld was run with superpages enabled (results above) and no stability issues were noticed.

A test program, along with a test kernel module, can be found at: https://people.freebsd.org/~luporl/sptest (The Makefile assumes host is an amd64 machine with a cross powerpc64 toolchain installed, although it should be easy to port it build natively) With the compiled program and module at current directory, running `./test all` runs all test cases, that exercises most superpage operations, such as: - promotion - demotion - enter - removal - unwire - protect - etc The test program should be run in single user mode, to avoid interference from other processes. Also, most test cases expect a file called "mmap" in the current directory, with a size of exactly 16MB. To create it, run `dd if=/dev/zero of=mmap bs=1m count=16`. Besides the test program, `stress` was used to simulate high memory usage, exercise swap and better test SP REF/CHG bits handling. The tests above were run both on a QEMU VM, with KVM enabled, and also directly on a POWER8 (previous patch version) and a POWER9 machine. Finally, buildworld was run with superpages enabled (results above) and no stability issues were noticed.