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path: root/arch/x86/oprofile/op_counter.h
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2009-07-20oprofile: Implement performance counter multiplexingJason Yeh
The number of hardware counters is limited. The multiplexing feature enables OProfile to gather more events than counters are provided by the hardware. This is realized by switching between events at an user specified time interval. A new file (/dev/oprofile/time_slice) is added for the user to specify the timer interval in ms. If the number of events to profile is higher than the number of hardware counters available, the patch will schedule a work queue that switches the event counter and re-writes the different sets of values into it. The switching mechanism needs to be implemented for each architecture to support multiplexing. This patch only implements AMD CPU support, but multiplexing can be easily extended for other models and architectures. There are follow-on patches that rework parts of this patch. Signed-off-by: Jason Yeh <jason.yeh@amd.com> Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-16oprofile: fixing whitespaces in arch/x86/oprofile/*Robert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-09-24Revert "Oprofile Multiplexing Patch"Robert Richter
Reverting commit 1a960b402a51d80abf54e3f8e4972374ffe5f22d for the main branch. Multiplexing will be tracked on a separate feature branch. Conflicts: arch/x86/oprofile/nmi_int.c
2008-07-26Oprofile Multiplexing PatchJason Yeh
This patch introduces multiplexing support for the Oprofile kernel module. It basically adds a new function pointer in oprofile_operator allowing each architecture to supply its callback to switch between different sets of event when the timer expires. Userspace tools can modify the time slice through /dev/oprofile/time_slice. It also modifies the number of counters exposed to the userspace through /dev/oprofile. For example, the number of counters for AMD CPUs are changed to 32 and multiplexed in the sets of 4. Signed-off-by: Jason Yeh <jason.yeh@amd.com> Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: oprofile-list <oprofile-list@lists.sourceforge.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-11i386: move oprofileThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>