The host-program-parameter (hpp) value of basic sample-data-entries designates
a SIE control block that is set by the LPP instruction in sie64a().
Non-zero values indicate guest samples, a value of zero indicates a host sample.
For perf samples, host and guest samples are distinguished using particular
PERF_MISC_* flags. The perf layer calls perf_misc_flags() to set the flags
based on the pt_regs content. For each sample-data-entry, the cpum_sf PMU
creates a pt_regs structure with the sample-data information. An additional
flag structure is added to easily distinguish between host and guest samples.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The trailer entry contains a timestamp of the time when the sample-data-block
became full. The timestamp specifies a TOD (time-of-day) value in either the
STCK or STCKE format.
Provide a helper function to return the TOD value depending on the setting of
time format indicator.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Ensure to reset the sample-data-block full indicator and the overflow counter
at the same time. This must be done atomically because the sampling hardware
is still active while full sample-data-block is processed.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Improve the sampling buffer allocation and add a function to reallocate and
increase the sampling buffer structure. The number of allocated buffer elements
(sample-data-blocks) are accounted. You can control the minimum and maximum
number these sample-data-blocks through the cpum_sfb_size kernel parameter.
The number hardware sample overflows (if any) are also accounted and stored
per perf event. During the PMU disable/enable calls, the accumulated overflow
counter is analyzed and, if necessary, the sampling buffer is dynamically
increased.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce reserve/release functions to share the sampling facility
between perf and oprofile.
Also improve error handling for the sampling facility support in perf.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The cpum_cf (counter facility) PMU does not support sampling events.
With cpum_sf (sampling facility), a PMU for sampling CPU cycles is
available.
Make cpum_sf the "default" PMU for PERF_COUNT_HW_CPU_CYCLES sampling
events but use the more precise cpum_cf PMU for non-sampling events.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce a perf PMU, "cpum_sf", to support the CPU-Measurement
Sampling Facility. You can control the sampling facility through
this perf PMU interfaces. Perf sampling events are created for
hardware samples.
For details about the CPU-Measurement Sampling Facility, see
"The Load-Program-Parameter and the CPU-Measurement Facilities" (SA23-2260).
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
