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NAME |SYNOPSIS |DESCRIPTION |MODIFIERS |OFFCORE_RESPONSE events |AUTHORS |COLOPHON | |
LIBPFM(3) Linux Programmer's ManualLIBPFM(3)libpfm_intel_tmt - support for Intel Tremont core PMU
#include <perfmon/pfmlib.h>PMU name: tmtPMU desc: Intel Tremont
The library supports the Intel Tremont core PMU.
The following modifiers are supported on Intel Tremont processors:uMeasure at user level which includes privilege levels 1, 2, 3. This corresponds toPFM_PLM3. This is a boolean modifier.kMeasure at kernel level which includes privilege level 0. This corresponds toPFM_PLM0. This is a boolean modifier.iInvert the meaning of the event. The counter will now count cycles in which the event isnotoccurring. This is a boolean modifiereEnable edge detection, i.e., count only when there is a state transition from no occurrence of the event to at least one occurrence. This modifier must be combined with a counter mask modifier (m) with a value greater or equal to one. This is a boolean modifier.cSet the counter mask value. The mask acts as a threshold. The counter will count the number of cycles in which the number of occurrences of the event is greater or equal to the threshold. This is an integer modifier with values in the range [0:255].
Intel Tremont provides two offcore_response events:OFFCORE_RESPONSE_0andOFFCORE_RESPONSE_1. TheOCRevent is aliased toOFFCORE_RESPONSE_0. Those events need special treatment in the performance monitoring infrastructure because each event uses an extra register to store some settings. Thus, in case multiple offcore_response events are monitored simultaneously, the kernel needs to manage the sharing of that extra register. The offcore_response event is exposed as a normal event by the library. The extra settings are exposed as regular umasks. The library takes care of encoding the events according for the underlying kernel interface. On Intel Tremont, it is not possible to combine the request, supplier, snoop, fields anymore to avoid invalid combinations. As such, the umasks provided by the library are the only ones supported and validated.
Stephane Eranian <eranian@gmail.com>
This page is part of theperfmon2 (a performance monitoring library) project. Information about the project can be found at ⟨http://perfmon2.sourceforge.net/⟩. If you have a bug report for this manual page, send it to perfmon2-devel@lists.sourceforge.net. This page was obtained from the project's upstream Git repository ⟨git://git.code.sf.net/p/perfmon2/libpfm4 perfmon2-libpfm4⟩ on 2025-08-11. (At that time, the date of the most recent commit that was found in the repository was 2025-06-29.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which isnot part of the original manual page), send a mail to man-pages@man7.org March, 2020LIBPFM(3)HTML rendering created 2025-09-06 byMichael Kerrisk, author ofThe Linux Programming Interface. For details of in-depthLinux/UNIX system programming training courses that I teach, lookhere. Hosting byjambit GmbH. | |