s390/cpum_sf: Add flag to process full SDBs only
Add the PERF_CPUM_SF_FULL_BLOCKS flag to process only sample-data-blocks that have the block-full-indicator bit set. Sample-data-blocks that are partially filled are discarded. Use this flag if the sampling buffer is likely to be shared among perf events that use different sampling modes. In such environments, flushing sample-data-blocks that are not completely filled, might cause invalid-data-formats. Setting PERF_CPUM_SF_FULL_BLOCKS prevents potentially invalid sampling data to be processed but, in contrast, also discards valid samples in partially filled sample-data-blocks. Note that sample-data-blocks might not become full for small sampling frequencies or for workload that is scheduled for tiny intervals. To sample with the PERF_CPUM_SF_FULL_BLOCKS flag, set the perf->attr.config1 to 0x0004. For example: perf record -e cpum_sf/config=0xB000,config1=0x0004/ Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Showing
Please register or sign in to comment