kernel/arch/powerpc/perf/isa207-common.c, branch linux-6.2.y

powerpc/perf: Update MMCR2 to support event exclude_idle

2022-06-29T09:42:41Z

struct perf_event_attr supports exclude counting of idle task. This is sent to kernel via perf_event_attr.exclude_idle and in perf tool, user can use ":I" event modifier to enable this for specific event. Monitor Mode Control Register 2 (MMCR2) SPR has control bits for each PMCs to freeze counting based on the Control Register CTRL[RUN] state. CTRL[RUN] is not set when idle task is running. Patch adds a check for event attr.exclude_idle to set MMCR2[FCnWAIT] bit. Signed-off-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210429050208.266619-1-maddy@linux.ibm.com

powerpc/perf: Fix the threshold compare group constraint for power9

2022-05-22T05:58:30Z

Thresh compare bits for a event is used to program thresh compare field in Monitor Mode Control Register A (MMCRA: 9-18 bits for power9). When scheduling events as a group, all events in that group should match value in threshold bits (like thresh compare, thresh control, thresh select). Otherwise event open for the sibling events should fail. But in the current code, incase thresh compare bits are not valid, we are not failing in group_constraint function which can result in invalid group schduling. Fix the issue by returning -1 incase event is threshold and threshold compare value is not valid. Thresh control bits in the event code is used to program thresh_ctl field in Monitor Mode Control Register A (MMCRA: 48-55). In below example, the scheduling of group events PM_MRK_INST_CMPL (873534401e0) and PM_THRESH_MET (8734340101ec) is expected to fail as both event request different thresh control bits and invalid thresh compare value. Result before the patch changes: [command]# perf stat -e "{r8735340401e0,r8734340101ec}" sleep 1 Performance counter stats for 'sleep 1': 11,048 r8735340401e0 1,967 r8734340101ec 1.001354036 seconds time elapsed 0.001421000 seconds user 0.000000000 seconds sys Result after the patch changes: [command]# perf stat -e "{r8735340401e0,r8734340101ec}" sleep 1 Error: The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (r8735340401e0). /bin/dmesg | grep -i perf may provide additional information. Fixes: 78a16d9fc1206 ("powerpc/perf: Avoid FAB_*_MATCH checks for power9") Signed-off-by: Kajol Jain Reviewed-by: Athira Rajeev Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220506061015.43916-2-kjain@linux.ibm.com

powerpc/perf: Fix the threshold compare group constraint for power10

2022-05-22T05:58:29Z

Thresh compare bits for a event is used to program thresh compare field in Monitor Mode Control Register A (MMCRA: 8-18 bits for power10). When scheduling events as a group, all events in that group should match value in threshold bits. Otherwise event open for the sibling events should fail. But in the current code, incase thresh compare bits are not valid, we are not failing in group_constraint function which can result in invalid group schduling. Fix the issue by returning -1 incase event is threshold and threshold compare value is not valid in group_constraint function. Patch also fixes the p10_thresh_cmp_val function to return -1, incase threshold bits are not valid and changes corresponding check in is_thresh_cmp_valid function to return false only when the thresh_cmp value is less then 0. Thresh control bits in the event code is used to program thresh_ctl field in Monitor Mode Control Register A (MMCRA: 48-55). In below example, the scheduling of group events PM_MRK_INST_CMPL (3534401e0) and PM_THRESH_MET (34340101ec) is expected to fail as both event request different thresh control bits. Result before the patch changes: [command]# perf stat -e "{r35340401e0,r34340101ec}" sleep 1 Performance counter stats for 'sleep 1': 8,482 r35340401e0 0 r34340101ec 1.001474838 seconds time elapsed 0.001145000 seconds user 0.000000000 seconds sys Result after the patch changes: [command]# perf stat -e "{r35340401e0,r34340101ec}" sleep 1 Performance counter stats for 'sleep 1': r35340401e0 r34340101ec 1.001499607 seconds time elapsed 0.000204000 seconds user 0.000760000 seconds sys Fixes: 82d2c16b350f7 ("powerpc/perf: Adds support for programming of Thresholding in P10") Signed-off-by: Kajol Jain Reviewed-by: Athira Rajeev Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220506061015.43916-1-kjain@linux.ibm.com

powerpc: fix typos in comments

2022-05-05T12:12:44Z

Various spelling mistakes in comments. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall Reviewed-by: Joel Stanley Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220430185654.5855-1-Julia.Lawall@inria.fr

powerpc: declare unmodified attribute_group usages const

2022-03-08T11:15:32Z

Inspired by (bd75b4ef4977: Constify static attribute_group structs), accepted by linux-next, reported: https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220210202805.7750-4-rikard.falkeborn@gmail.com/ Nearly all singletons of type struct attribute_group are never modified, and so are candidates for being const. Declare them as const. Signed-off-by: Rohan McLure Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220307231414.86560-1-rmclure@linux.ibm.com

powerpc/perf: Add data source encodings for power10 platform

2021-12-16T10:31:44Z

The code represent memory/cache level data based on PERF_MEM_LVL_* namespace, which is in the process of deprication in the favour of newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields. Add data source encodings to represent cache/memory data based on newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields. Add data source encodings to represent data coming from local memory/Remote memory/distant memory and remote/distant cache hits. In order to represent data coming from OpenCAPI cache/memory, we use LVLNUM "PMEM" field which is used to present persistent memory accesses. Result in power10 system with patch changes: localhost:# ./perf mem report --sort="mem,sym,dso" --stdio # Overhead Samples Memory access Symbol Shared Object # ........ ............ ........................ .......................... ................ # 29.46% 2331 L1 or L1 hit [.] __random libc-2.28.so 23.11% 2121 L1 or L1 hit [.] producer_populate_cache producer_consumer 18.56% 1758 L1 or L1 hit [.] __random_r libc-2.28.so 15.64% 1559 L2 or L2 hit [.] __random libc-2.28.so ..... 0.09% 5 Remote socket, same board Any cache hit [.] __random libc-2.28.so 0.07% 4 Remote socket, same board Any cache hit [.] __random libc-2.28.so ..... Signed-off-by: Kajol Jain Reviewed-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211206091749.87585-5-kjain@linux.ibm.com

powerpc/perf: Add encodings to represent data based on newer composite PERF_MEM_LVLNUM* fields

2021-12-16T10:31:44Z

The code represent data coming from L1/L2/L3 cache hits based on PERF_MEM_LVL_* namespace, which is in the process of deprecation in the favour of newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields. Add data source encodings to represent L1/L2/L3 cache hits based on newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields for power10 and older platforms Result in power9 system without patch changes: localhost:# ./perf mem report --sort="mem,sym,dso" --stdio # Overhead Samples Memory access Symbol Shared Object # ........ ............ ........................ ................................. ................ # 29.51% 1 L2 hit [k] perf_event_exec [kernel.vmlinux] 27.05% 1 L1 hit [k] perf_ctx_unlock [kernel.vmlinux] 13.93% 1 L1 hit [k] vtime_delta [kernel.vmlinux] 13.11% 1 L1 hit [k] prepend_path.isra.11 [kernel.vmlinux] 8.20% 1 L1 hit [.] 00000038.plt_call.__GI_strlen libc-2.28.so 8.20% 1 L1 hit [k] perf_event_interrupt [kernel.vmlinux] Result in power9 system with patch changes: localhost:# ./perf mem report --sort="mem,sym,dso" --stdio # Overhead Samples Memory access Symbol Shared Object # ........ ............ ........................ .......................... ................ # 36.63% 1 L2 or L2 hit [k] perf_event_exec [kernel.vmlinux] 25.50% 1 L1 or L1 hit [k] vtime_delta [kernel.vmlinux] 13.12% 1 L1 or L1 hit [k] unmap_region [kernel.vmlinux] 12.62% 1 L1 or L1 hit [k] perf_sample_event_took [kernel.vmlinux] 6.93% 1 L1 or L1 hit [k] perf_ctx_unlock [kernel.vmlinux] 5.20% 1 L1 or L1 hit [.] __memcpy_power7 libc-2.28.so Signed-off-by: Kajol Jain Reviewed-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211206091749.87585-4-kjain@linux.ibm.com

powerpc/perf: Fix data source encodings for L2.1 and L3.1 accesses

2021-10-19T15:27:01Z

Fix the data source encodings to represent L2.1/L3.1(another core's L2/L3 on the same node) accesses properly for power10 and older plaforms. Add new macros(LEVEL/REM) which can be used to add mem_lvl_num and remote field data inside perf_mem_data_src structure. Result in power9 system with patch changes: localhost:~/linux/tools/perf # ./perf mem report | grep Remote 0.01% 1 252 Remote core, same node L3 or L3 hit [.] 0x0000000000002dd0 producer_consumer [.] 0x00007fff7f25eb90 anon HitM N/A No N/A 0 0 0.01% 1 220 Remote core, same node L3 or L3 hit [.] 0x0000000000002dd0 producer_consumer [.] 0x00007fff77776d90 anon HitM N/A No N/A 0 0 0.01% 1 220 Remote core, same node L3 or L3 hit [.] 0x0000000000002dd0 producer_consumer [.] 0x00007fff817d9410 anon HitM N/A No N/A 0 0 Fixes: 79e96f8f930d ("powerpc/perf: Export memory hierarchy info to user space") Signed-off-by: Kajol Jain Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20211006140654.298352-5-kjain@linux.ibm.com

powerpc/perf: Fix sampled instruction type for larx/stcx

2021-04-22T15:38:02Z

Sampled Instruction Event Register (SIER) field [46:48] identifies the sampled instruction type. ISA v3.1 says value of 0b111 for this field as reserved, but in POWER10 it denotes LARX/STCX type which will hopefully be fixed in ISA v3.1 update. Patch fixes the functions to handle type value 7 for CPU_FTR_ARCH_31. Fixes: a64e697cef23 ("powerpc/perf: power10 Performance Monitoring support") Signed-off-by: Athira Rajeev Reviewed-by: Madhavan Srinivasan [mpe: Avoid reading mmcra until necessary, use early return to deindent if block] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1614858937-1485-1-git-send-email-atrajeev@linux.vnet.ibm.com

powerpc/perf: Expose processor pipeline stage cycles using PERF_SAMPLE_WEIGHT_STRUCT

2021-04-20T04:22:23Z

Performance Monitoring Unit (PMU) registers in powerpc provides information on cycles elapsed between different stages in the pipeline. This can be used for application tuning. On ISA v3.1 platform, this information is exposed by sampling registers. Patch adds kernel support to capture two of the cycle counters as part of perf sample using the sample type: PERF_SAMPLE_WEIGHT_STRUCT. The power PMU function 'get_mem_weight' currently uses 64 bit weight field of perf_sample_data to capture memory latency. But following the introduction of PERF_SAMPLE_WEIGHT_TYPE, weight field could contain 64-bit or 32-bit value depending on the architexture support for PERF_SAMPLE_WEIGHT_STRUCT. Patches uses WEIGHT_STRUCT to expose the pipeline stage cycles info. Hence update the ppmu functions to work for 64-bit and 32-bit weight values. If the sample type is PERF_SAMPLE_WEIGHT, use the 64-bit weight field. if the sample type is PERF_SAMPLE_WEIGHT_STRUCT, memory subsystem latency is stored in the low 32bits of perf_sample_weight structure. Also for CPU_FTR_ARCH_31, capture the two cycle counter information in two 16 bit fields of perf_sample_weight structure. Signed-off-by: Athira Rajeev Reviewed-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1616425047-1666-2-git-send-email-atrajeev@linux.vnet.ibm.com