# $Id: Kconfig,v 1.7.2.2 2004/11/13 16:32:05 mikpe Exp $
# Performance-monitoring counters driver configuration
#
menu "Performance-monitoring counters support"
config PERFCTR
tristate "Performance monitoring counters support"
help
This driver provides access to the performance-monitoring counter
registers available in some (but not all) modern processors.
These special-purpose registers can be programmed to count low-level
performance-related events which occur during program execution,
such as cache misses, pipeline stalls, etc.
You can safely say Y here, even if you intend to run the kernel
on a processor without performance-monitoring counters.
You can also say M here to compile the driver as a module; the
module will be called `perfctr'.
config KPERFCTR
bool
depends on PERFCTR
default y
config PERFCTR_DEBUG
bool "Additional internal consistency checks"
depends on PERFCTR
help
This option enables additional internal consistency checking in
the perfctr driver. The scope of these checks is unspecified and
may vary between different versions of the driver.
Enabling this option will reduce performance, so say N unless you
are debugging the driver.
config PERFCTR_INIT_TESTS
bool "Init-time hardware tests"
depends on PERFCTR
help
This option makes the driver perform additional hardware tests
during initialisation, and log their results in the kernel's
message buffer. For most supported processors, these tests simply
measure the runtime overheads of performance counter operations.
If you have a less well-known processor (one not listed in the
etc/costs/ directory in the user-space package), you should enable
this option and email the results to the perfctr developers.
If unsure, say N.
config PERFCTR_VIRTUAL
bool "Virtual performance counters support"
depends on PERFCTR
help
The processor's performance-monitoring counters are special-purpose
global registers. This option adds support for virtual per-process
performance-monitoring counters which only run when the process
to which they belong is executing. This improves the accuracy of
performance measurements by reducing "noise" from other processes.
Say Y.
config PERFCTR_GLOBAL
bool "Global performance counters support"
depends on PERFCTR
help
This option adds driver support for global-mode (system-wide)
performance-monitoring counters. In this mode, the driver allows
each performance-monitoring counter on each processor to be
controlled and read. The driver provides a sampling timer to
maintain 64-bit accumulated event counts.
Global-mode performance counters cannot be used if some process
is currently using virtual-mode performance counters, and vice versa.
Say Y.
config PERFCTR_INTERRUPT_SUPPORT
prompt "Performance counter overflow interrupt support" if PPC
bool
depends on PERFCTR
default y if X86_LOCAL_APIC
config PERFCTR_CPUS_FORBIDDEN_MASK
bool
depends on PERFCTR
default y if X86 && SMP
endmenu