CoreSight

coresight@lists.linaro.org

5 participants
2644 discussions

Re: [PATCH v2 2/2] arm64: dts: qcom: kaanapali: fix traceNoC probe issue

by Leo Yan

Hi Jie, On Fri, Jun 26, 2026 at 10:03:41AM +0800, Jie Gan wrote: [...] > Hi Leo, > > To be honest, I would prefer not to modify the interconnect platform driver. > On some Qualcomm platforms, multiple itnoc devices reside within small > blocks(one or more than one for each block) and are connected to a dummy > source. In such cases, two ATIDs are allocated for a path (the dummy source > and the itnoc), which is inefficient. This is why the itnoc platform driver > created to avoid this waste. > > The TraceNoC (called as AG TraceNoC) is a generic TraceNoC device which > connected to multiple source and link devices, aggregating data from all > source devices into a single output path. As I said, it may be fragile to couple a specific device property (ATID) to the AMBA driver. You're now facing a case where a device cannot be registered as an AMBA device, so it cannot use ATID. Likewise, I can imagine in future where a device is registered as an AMBA device, but you don't want ATID. > This device is implemented as an AMBA device but lacks proper hardware > configuration. As a result, it must be handled in the driver as a > workaround, which unfortunately breaks the original design intent. Seems to me, it is not reasonable to pretend an AMBA device but AMBA ID registers are absent. How about add a new DT property ("qcom,tnoc-enable-atid") to force enabling ATID? Thanks, Leo

3 months

Re: [PATCH v2 2/2] arm64: dts: qcom: kaanapali: fix traceNoC probe issue

by Leo Yan

On Thu, Jun 25, 2026 at 09:01:18AM +0800, Jie Gan wrote: [...] > > > However, I believe it is acceptable to allocate an ATID for the itNoC device > > > and the issue can be fixed with this way. > > > > I think so. > > Hi Suzuki/Leo > > Which solution do you prefer to address the issue? I will leave this to Suzuki. > The interconnect traceNoC platform driver is intended for the itnoc device, > implying that no TPDM devices are connected to it. So, if I modify it to > allocate an ATID, I think it would be better to rename the “itnoc” node > accordingly? Or it's ok to leave it as-is? > > BTW, the traceNoC device definitely is an AMBA device with CID/PID > registers. Just to share a bit thoughts on the driver's design. I think it would be better to keep the probe function generic. The AMBA probe should not be specific to TraceNoC, and the platform probe should not be only dedicated to the interconnect TraceNoC. The probe function should simply handle a device that appears on either the AMBA bus or the platform bus. So the question is: if allocat an ATID for all traceNoC devices, do you still need to distinguish TraceNoC types? If no, then the code can be unified. Thanks, Leo

3 months

Re: [PATCH v2 2/2] arm64: dts: qcom: kaanapali: fix traceNoC probe issue

by Leo Yan

On Wed, Jun 24, 2026 at 11:08:32PM +0800, Jie Gan wrote: [...] > > Why does it fail ? power management ? hw broken ? Is it really AMBA or > > do you pretend that to be an AMBA device by faking the CID/PID? > > The CID reads as 0 from the register, which I suspect is a hardware design > issue. I have not yet confirmed this with the hardware team. As a > workaround, I provided a fake periphid via a DT property to bypass > amba_read_periphid. > > > Leo commented in other thread: > >>tnoc.c registers both an AMBA driver and a platform driver. Shouldn't >>it > >>be registered as a platform device instead? > > The platform driver is intended for the interconnect TraceNoC device and is > not designed to allocate an ATID. The issue is that the TPDM device borrows > the ATID from the TraceNoC device, resulting in the ATID always being 0 when > associated with an interconnect NoC device. > > However, I believe it is acceptable to allocate an ATID for the itNoC device > and the issue can be fixed with this way. I think so.

3 months

Re: [PATCH v2 2/2] arm64: dts: qcom: kaanapali: fix traceNoC probe issue

by Leo Yan

On Wed, Jun 24, 2026 at 05:49:26PM +0800, Jie Gan wrote: > The AMBA bus attempts to read the CID/PID of a device before invoking > its probe function if the arm,primecell-periphid property is absent. > This causes a deferred probe issue for the TraceNoC device, as the > CID/PID cannot be read from the periphid register. > Add the arm,primecell-periphid property to bypass the AMBA bus > check and resolve the probe issue. tnoc.c registers both an AMBA driver and a platform driver. Shouldn't it be registered as a platform device instead? Thanks, Leo

3 months

Re: [PATCH v2 2/2] arm64: dts: qcom: kaanapali: fix traceNoC probe issue

by Suzuki K Poulose

On 24/06/2026 14:48, Jie Gan wrote: > > > On 6/24/2026 9:27 PM, Konrad Dybcio wrote: >> On 6/24/26 11:49 AM, Jie Gan wrote: >>> The AMBA bus attempts to read the CID/PID of a device before invoking >>> its probe function if the arm,primecell-periphid property is absent. >>> This causes a deferred probe issue for the TraceNoC device, as the >>> CID/PID cannot be read from the periphid register. >> >> Why does it probe defer? >> > > For an AMBA device, the periphid is mandatory for probing. In the > amba_match function, AMBA attempts to read the periphid from the CID/PID > registers if the arm,primecell-periphid property is absent in the device > tree. If this read fails, it returns -EPROBE_DEFER, and the probe > ultimately fails. Why does it fail ? power management ? hw broken ? Is it really AMBA or do you pretend that to be an AMBA device by faking the CID/PID? Suzuki > Most AMBA devices expose valid CID/PID registers, so specifying > arm,primecell-periphid in the device tree is usually unnecessary. > However, for the TraceNoC device in this case, AMBA cannot reliably read > the periphid from the corresponding registers. > >> And is this required for all TNOC devices? > > So far, the TNOC device has been added to sm8750, Glymur, and Kaanapali > platforms, and all exhibit probe failures due to the same root cause. > > I prefer to fix it on Kaanapali first. > > Thanks, > Jie > >> >> Konrad >

3 months

Re: [PATCH v10 0/5] Add Qualcomm extended CTI support

by Leo Yan

On Mon, Jun 15, 2026 at 08:32:28PM +0800, Yingchao Deng wrote: > The Qualcomm extended CTI is a heavily parameterized version of ARM’s > CSCTI. It allows a debugger to send to trigger events to a processor or to > send a trigger event to one or more processors when a trigger event occurs > on another processor on the same SoC, or even between SoCs. > > Qualcomm extended CTI supports up to 128 triggers. And some of the register > offsets are changed. > > The commands to configure CTI triggers are the same as ARM's CTI. This series looks good to me and I tested: - Confirmed no any change for standard CTI; - Perf command; - Build bisection. Tested-by: Leo Yan <leo.yan(a)arm.com> Mike may also want to take a look in case there is any overlap with his claim tags init patch [1]. I don't have a strong preference on which series goes in first, as the claim tag handling in this series looks clean enough to me. @Yingchao, just a small suggestion: rc1–rc4 is usually the best window for getting patches merged. If you receive comments and are able to address them quickly, it may be worth respin patches during that period to try catching the next merge window. This is no guarantees, just thought it might be useful to share as a general tip :) [1] https://lore.kernel.org/linux-arm-kernel/20260619160148.499223-2-mike.leach…

3 months

[PATCH v9 0/9] perf cs-etm: Support thread stack and callchain

by Leo Yan

This series adds thread-stack and synthesized callchain support for Arm CoreSight, which comes from older series [1] but heavily rewritten. CS ETM previously kept last-branch state in a per-trace-queue buffer. That effectively makes the state per CPU, while the call/return history belongs to a thread. This series moves branch tracking to the common thread-stack code. The series records CoreSight branches with thread_stack__event(), uses thread_stack__br_sample() for last branch entries, flushes thread stacks after decoder resets. A decoder reset between AUX trace buffers is treated as a global trace discontinuity, so all thread stacks are flushed, so avoids carrying stale call/return history across a trace discontinuity. One limitation remains for instructions emulated by the kernel. In that case the exception return address may not match the return address stored in the thread stack, because after exception return can be one instruction ahead. The stack can still recover when a later return matches an upper caller. Given emulated instructions are not the common target for performance callchain analysis. Supporting this would require extending the common thread-stack path to accept both the real target address and an adjusted address for stack matching, so this series leaves that extra complexity out. The series has been tested on Orion6 board: perf test 136 -vvv 136: CoreSight synthesized callchain: --- start --- test child forked, pid 3539 ---- end(0) ---- 136: CoreSight synthesized callchain : Ok perf script --itrace=g16i10il64 callchain_test 17468 [005] 1031003.229943: 10 instructions: aaaac32507c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 17468 [005] 1031003.229943: 10 instructions: aaaac3250774 do_svc+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac3250798 print+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507b0 foo+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507c8 main+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 17468 [005] 1031003.229944: 10 instructions: ffff800080010c20 vectors+0x420 ([kernel.kallsyms]) aaaac3250784 do_svc+0x1c (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac3250798 print+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507b0 foo+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507c8 main+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) Note, the test fails on Juno board which is caused by many discontinuity packets (mainly caused by NO_SYNC elem). This is likely caused by the FIFO overflow on the path. [1] https://lore.kernel.org/linux-arm-kernel/20200220052701.7754-1-leo.yan@lina… Signed-off-by: Leo Yan <leo.yan(a)arm.com> --- Changes in v9: - Added patch 01 to fixed thread leak during trace queue init (sashiko). - Added check in instruction and branch samples in cs_etm__add_stack_event() (sashiko). - Released frontend_thread properly in cs_etm__context() (sashiko). - Refined cs_etm__flush_all_stack() to use switch (sashiko). - Gathered James' review tags. - Rebased on the latest perf-tools-next. - Link to v8: https://lore.kernel.org/r/20260611-b4-arm_cs_callchain_support_v1-v8-0-7379… Changes in v8: - Updated test_arm_coresight_disasm.sh to pass "--itrace=b" and updated examples in arm-cs-trace-disasm.py (James). - Removed static annotation in callchain workload and renamed functions with prefix "callchain_" to reduce naming conflict (James). - For callchain test pre-condition check, removed the aarch64 check and added the root permission check (James). - Resolved the shellcheck errors (James). - Link to v7: https://lore.kernel.org/r/20260611-b4-arm_cs_callchain_support_v1-v7-0-1ba7… Changes in v7: - Rebased on the latest perf-tools-next. - Used struct_size() for allocation callchain struct (James). - Added a helper cs_etm__packet_has_taken_branch() (James). - Minor improvements for the callchain test (used record-ctl FIFO and reworked the validation callstack push / pop). - Link to v6: https://lore.kernel.org/r/20260526-b4-arm_cs_callchain_support_v1-v6-0-f9f4… Changes in v6: - Heavily rewrote the patches since restarted the work after 6 years. - Changed to use the common thread-stack for branch stack and callchain management. - Added a callchain test. - Link to v5: https://lore.kernel.org/linux-arm-kernel/20200220052701.7754-1-leo.yan@lina… Changes in v5: - Addressed Mike's suggestion for performance improvement for function cs_etm__instr_addr() for quick calculation for non T32; - Removed the patch 'perf cs-etm: Synchronize instruction sample with the thread stack' (Mike); - Fixed the issue for exception is taken for branch target address accessing, for the branch sample and stack thread handling, the related patches are 01, 02, 07; - Fixed the stack thread handling for instruction emulation and single step with patches 08, 09. - Link to v4: https://lore.kernel.org/linux-arm-kernel/20200203020716.31832-1-leo.yan@lin… --- Leo Yan (9): perf cs-etm: Fix thread leaks on trace queue init failure perf cs-etm: Filter synthesized branch samples perf cs-etm: Decode ETE exception packets perf cs-etm: Refactor instruction size handling perf cs-etm: Use thread-stack for last branch entries perf cs-etm: Flush thread stacks after decoder reset perf cs-etm: Support call indentation perf cs-etm: Synthesize callchains for instruction samples perf test: Add Arm CoreSight callchain test tools/perf/Documentation/perf-test.txt | 6 +- tools/perf/scripts/python/arm-cs-trace-disasm.py | 9 +- tools/perf/tests/builtin-test.c | 1 + tools/perf/tests/shell/coresight/callchain.sh | 172 ++++++++++ .../shell/coresight/test_arm_coresight_disasm.sh | 4 +- tools/perf/tests/tests.h | 1 + tools/perf/tests/workloads/Build | 2 + tools/perf/tests/workloads/callchain.c | 33 ++ tools/perf/util/cs-etm.c | 367 +++++++++++++-------- 9 files changed, 446 insertions(+), 149 deletions(-) --- base-commit: 44543bb53ebfecb5ce4e890053a666affab9e482 change-id: 20260521-b4-arm_cs_callchain_support_v1-2c2a70719bcc Best regards, -- Leo Yan <leo.yan(a)arm.com>

3 months, 1 week

[PATCH v8 0/8] perf cs-etm: Support thread stack and callchain

by Leo Yan

This series adds thread-stack and synthesized callchain support for Arm CoreSight, which comes from older series [1] but heavily rewritten. CS ETM previously kept last-branch state in a per-trace-queue buffer. That effectively makes the state per CPU, while the call/return history belongs to a thread. This series moves branch tracking to the common thread-stack code. The series records CoreSight branches with thread_stack__event(), uses thread_stack__br_sample() for last branch entries, flushes thread stacks after decoder resets. A decoder reset between AUX trace buffers is treated as a global trace discontinuity, so all thread stacks are flushed, so avoids carrying stale call/return history across a trace discontinuity. One limitation remains for instructions emulated by the kernel. In that case the exception return address may not match the return address stored in the thread stack, because after exception return can be one instruction ahead. The stack can still recover when a later return matches an upper caller. Given emulated instructions are not the common target for performance callchain analysis. Supporting this would require extending the common thread-stack path to accept both the real target address and an adjusted address for stack matching, so this series leaves that extra complexity out. The series has been tested on Orion6 board: perf test 136 -vvv 136: CoreSight synthesized callchain: --- start --- test child forked, pid 3539 ---- end(0) ---- 136: CoreSight synthesized callchain : Ok perf script --itrace=g16i10il64 callchain_test 17468 [005] 1031003.229943: 10 instructions: aaaac32507c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 17468 [005] 1031003.229943: 10 instructions: aaaac3250774 do_svc+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac3250798 print+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507b0 foo+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507c8 main+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 17468 [005] 1031003.229944: 10 instructions: ffff800080010c20 vectors+0x420 ([kernel.kallsyms]) aaaac3250784 do_svc+0x1c (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac3250798 print+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507b0 foo+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507c8 main+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) Note, the test fails on Juno board which is caused by many discontinuity packets (mainly caused by NO_SYNC elem). This is likely caused by the FIFO overflow on the path. [1] https://lore.kernel.org/linux-arm-kernel/20200220052701.7754-1-leo.yan@lina… Signed-off-by: Leo Yan <leo.yan(a)arm.com> --- Changes in v8: - Updated test_arm_coresight_disasm.sh to pass "--itrace=b" and updated examples in arm-cs-trace-disasm.py (James). - Removed static annotation in callchain workload and renamed functions with prefix "callchain_" to reduce naming conflict (James). - For callchain test pre-condition check, removed the aarch64 check and added the root permission check (James). - Resolved the shellcheck errors (James). - Link to v7: https://lore.kernel.org/r/20260611-b4-arm_cs_callchain_support_v1-v7-0-1ba7… Changes in v7: - Rebased on the latest perf-tools-next. - Used struct_size() for allocation callchain struct (James). - Added a helper cs_etm__packet_has_taken_branch() (James). - Minor improvements for the callchain test (used record-ctl FIFO and reworked the validation callstack push / pop). - Link to v6: https://lore.kernel.org/r/20260526-b4-arm_cs_callchain_support_v1-v6-0-f9f4… Changes in v6: - Heavily rewrote the patches since restarted the work after 6 years. - Changed to use the common thread-stack for branch stack and callchain management. - Added a callchain test. - Link to v5: https://lore.kernel.org/linux-arm-kernel/20200220052701.7754-1-leo.yan@lina… Changes in v5: - Addressed Mike's suggestion for performance improvement for function cs_etm__instr_addr() for quick calculation for non T32; - Removed the patch 'perf cs-etm: Synchronize instruction sample with the thread stack' (Mike); - Fixed the issue for exception is taken for branch target address accessing, for the branch sample and stack thread handling, the related patches are 01, 02, 07; - Fixed the stack thread handling for instruction emulation and single step with patches 08, 09. - Link to v4: https://lore.kernel.org/linux-arm-kernel/20200203020716.31832-1-leo.yan@lin… Changes in v4: - Split out separate patch set for instruction samples fixing. - Rebased on latest perf/core branch. - Link to v3: https://lore.kernel.org/linux-arm-kernel/20191005091614.11635-1-leo.yan@lin… --- Leo Yan (8): perf cs-etm: Filter synthesized branch samples perf cs-etm: Decode ETE exception packets perf cs-etm: Refactor instruction size handling perf cs-etm: Use thread-stack for last branch entries perf cs-etm: Flush thread stacks after decoder reset perf cs-etm: Support call indentation perf cs-etm: Synthesize callchains for instruction samples perf test: Add Arm CoreSight callchain test tools/perf/Documentation/perf-test.txt | 6 +- tools/perf/scripts/python/arm-cs-trace-disasm.py | 9 +- tools/perf/tests/builtin-test.c | 1 + tools/perf/tests/shell/coresight/callchain.sh | 172 ++++++++++ .../shell/coresight/test_arm_coresight_disasm.sh | 4 +- tools/perf/tests/tests.h | 1 + tools/perf/tests/workloads/Build | 2 + tools/perf/tests/workloads/callchain.c | 33 ++ tools/perf/util/cs-etm.c | 351 ++++++++++++--------- 9 files changed, 430 insertions(+), 149 deletions(-) --- base-commit: 7336514f41e75d44782fee7e0990d4195a3d3161 change-id: 20260521-b4-arm_cs_callchain_support_v1-2c2a70719bcc Best regards, -- Leo Yan <leo.yan(a)arm.com>

3 months, 2 weeks

[PATCH v7 0/8] perf cs-etm: Support thread stack and callchain

by Leo Yan

This series adds thread-stack and synthesized callchain support for Arm CoreSight, which comes from older series [1] but heavily rewritten. CS ETM previously kept last-branch state in a per-trace-queue buffer. That effectively makes the state per CPU, while the call/return history belongs to a thread. This series moves branch tracking to the common thread-stack code. The series records CoreSight branches with thread_stack__event(), uses thread_stack__br_sample() for last branch entries, flushes thread stacks after decoder resets. A decoder reset between AUX trace buffers is treated as a global trace discontinuity, so all thread stacks are flushed, so avoids carrying stale call/return history across a trace discontinuity. One limitation remains for instructions emulated by the kernel. In that case the exception return address may not match the return address stored in the thread stack, because after exception return can be one instruction ahead. The stack can still recover when a later return matches an upper caller. Given emulated instructions are not the common target for performance callchain analysis. Supporting this would require extending the common thread-stack path to accept both the real target address and an adjusted address for stack matching, so this series leaves that extra complexity out. The series has been tested on Orion6 board: perf test 136 -vvv 136: CoreSight synthesized callchain: --- start --- test child forked, pid 3539 ---- end(0) ---- 136: CoreSight synthesized callchain : Ok perf script --itrace=g16i10il64 callchain_test 17468 [005] 1031003.229943: 10 instructions: aaaac32507c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 17468 [005] 1031003.229943: 10 instructions: aaaac3250774 do_svc+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac3250798 print+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507b0 foo+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507c8 main+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 17468 [005] 1031003.229944: 10 instructions: ffff800080010c20 vectors+0x420 ([kernel.kallsyms]) aaaac3250784 do_svc+0x1c (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac3250798 print+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507b0 foo+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) aaaac32507c8 main+0xc (/home/kernel/leoy/test_cs_callchain/callchain_test) ffff90bd225c __libc_start_call_main+0x7c (/usr/lib/aarch64-linux-gnu/libc.so.6) ffff90bd233c call_init+0x9c (inlined) ffff90bd233c __libc_start_main_impl+0x9c (inlined) aaaac3250670 _start+0x30 (/home/kernel/leoy/test_cs_callchain/callchain_test) Note, the test fails on Juno board which is caused by many discontinuity packets (mainly caused by NO_SYNC elem). This is likely caused by the FIFO overflow on the path. [1] https://lore.kernel.org/linux-arm-kernel/20200220052701.7754-1-leo.yan@lina… Signed-off-by: Leo Yan <leo.yan(a)arm.com> --- Changes in v7: - Rebased on the latest perf-tools-next. - Used struct_size() for allocation callchain struct (James). - Added a helper cs_etm__packet_has_taken_branch() (James). - Minor improvements for the callchain test (used record-ctl FIFO and reworked the validation callstack push / pop). - Link to v6: https://lore.kernel.org/r/20260526-b4-arm_cs_callchain_support_v1-v6-0-f9f4… Changes in v6: - Heavily rewrote the patches since restarted the work after 6 years. - Changed to use the common thread-stack for branch stack and callchain management. - Added a callchain test. - Link to v5: https://lore.kernel.org/linux-arm-kernel/20200220052701.7754-1-leo.yan@lina… Changes in v5: - Addressed Mike's suggestion for performance improvement for function cs_etm__instr_addr() for quick calculation for non T32; - Removed the patch 'perf cs-etm: Synchronize instruction sample with the thread stack' (Mike); - Fixed the issue for exception is taken for branch target address accessing, for the branch sample and stack thread handling, the related patches are 01, 02, 07; - Fixed the stack thread handling for instruction emulation and single step with patches 08, 09. - Link to v4: https://lore.kernel.org/linux-arm-kernel/20200203020716.31832-1-leo.yan@lin… Changes in v4: - Split out separate patch set for instruction samples fixing. - Rebased on latest perf/core branch. - Link to v3: https://lore.kernel.org/linux-arm-kernel/20191005091614.11635-1-leo.yan@lin… --- Leo Yan (8): perf cs-etm: Filter synthesized branch samples perf cs-etm: Decode ETE exception packets perf cs-etm: Refactor instruction size handling perf cs-etm: Use thread-stack for last branch entries perf cs-etm: Flush thread stacks after decoder reset perf cs-etm: Support call indentation perf cs-etm: Synthesize callchains for instruction samples perf test: Add Arm CoreSight callchain test tools/perf/Documentation/perf-test.txt | 6 +- tools/perf/tests/builtin-test.c | 1 + tools/perf/tests/shell/coresight/callchain.sh | 168 ++++++++++++ tools/perf/tests/tests.h | 1 + tools/perf/tests/workloads/Build | 2 + tools/perf/tests/workloads/callchain.c | 24 ++ tools/perf/util/cs-etm.c | 351 +++++++++++++++----------- 7 files changed, 410 insertions(+), 143 deletions(-) --- base-commit: 7336514f41e75d44782fee7e0990d4195a3d3161 change-id: 20260521-b4-arm_cs_callchain_support_v1-2c2a70719bcc Best regards, -- Leo Yan <leo.yan(a)arm.com>

3 months, 2 weeks

[PATCH v5 00/19] perf cs-etm: Queue context packets for frontend

by James Clark

Fix thread tracking when decoding Coresight trace and add a new test for it. The new test is added as a Perf test workload instead of a custom binary with its own build system, but this requires a new feature in Perf test to pass in control pipes which can enable and disable events. This scopes the recording to just the workload and helps to reduce the amount of data recorded in tracing tests. With this new feature we can re-write all of the Coresight tests to make use of it and remove the remaining binaries which fixes the following issues: * They didn't work in out of source builds * A lot of the tests unnecessarily required root and didn't skip without it * They were mainly qualitative tests which didn't look for specific behavior Most importantly, the long build and runtime has been reduced. On a Radxa Orion O6, unroll_loop_thread.c took 37s to compile which is longer than the entire Perf build. Now the build time is negligible and the before and after test runtimes for all the Coresight tests are: | N1SDP | Orion O6 ----------------------------------- Before | 4m 0s | 14m 49s After | 26s | 56s ----------------------------------- Signed-off-by: James Clark <james.clark(a)linaro.org> --- Changes in v5: - Forgot to include this change: - Test for actual length of expected raw dump (Leo) - Link to v4: https://lore.kernel.org/r/20260609-james-cs-context-tracking-fix-v4-0-44f9f… Changes in v4: - Rename workload-ctl to record-ctl and improve docs (Leo) - Use new packet argument everywhere in cs_etm__synth_instruction_sample() (Sashiko) - Test for actual length of expected raw dump (Leo) - Use -fno-inline instead of keyword (Leo) - Don't test any brace or call lines in deterministic test - Make sure context switch loop test does cleanup on failure (Sashiko) - Remove undef int overflows in workloads (Sashiko) - Link to v3: https://lore.kernel.org/r/20260603-james-cs-context-tracking-fix-v3-0-c3929… Changes in v3: - Minor sashiko comments - Close some more pipes - Fix warning messages - Error handling improvements - Pass packet into cs_etm__synth_instruction_sample() - Fixup stale comment (Leo) - Link to v2: https://lore.kernel.org/r/20260602-james-cs-context-tracking-fix-v2-0-85b5c… Changes in v2: - Add --workload-ctl option to Perf test - Re-write all the Coresight tests and speed them up - Pass packet to memory access function so frontend can use either the previous or current packet's EL - Link to v1: https://lore.kernel.org/r/20260526-james-cs-context-tracking-fix-v1-0-ebd60… --- James Clark (19): perf cs-etm: Queue context packets for frontend perf test: Add workload-ctl option perf test: Add a workload that forces context switches perf test cs-etm: Test process attribution perf test: Add deterministic workload perf test cs-etm: Replace unroll loop thread with deterministic decode test perf test cs-etm: Remove asm_pure_loop test perf test cs-etm: Replace memcpy test with raw dump stress test perf test: Add named_threads workload perf test cs-etm: Test decoding for concurrent threads test perf test cs-etm: Remove duplicate branch tests perf test cs-etm: Skip if not root perf test cs-etm: Reduce snapshot size perf test cs-etm: Speed up basic test perf test cs-etm: Remove unused Coresight workloads perf test cs-etm: Make disassembly test use kcore perf test cs-etm: Add all branch instructions to test perf test cs-etm: Speed up disassembly test perf test cs-etm: Move existing tests to coresight folder Documentation/trace/coresight/coresight-perf.rst | 78 +------ MAINTAINERS | 2 - tools/perf/Documentation/perf-test.txt | 24 ++- tools/perf/Makefile.perf | 14 +- tools/perf/scripts/python/arm-cs-trace-disasm.py | 20 +- tools/perf/tests/builtin-test.c | 187 +++++++++++++++- tools/perf/tests/shell/coresight/Makefile | 29 --- .../perf/tests/shell/coresight/Makefile.miniconfig | 14 -- tools/perf/tests/shell/coresight/asm_pure_loop.sh | 22 -- .../tests/shell/coresight/asm_pure_loop/.gitignore | 1 - .../tests/shell/coresight/asm_pure_loop/Makefile | 34 --- .../shell/coresight/asm_pure_loop/asm_pure_loop.S | 30 --- .../tests/shell/coresight/concurrent_threads.sh | 45 ++++ .../tests/shell/coresight/context_switch_thread.sh | 69 ++++++ tools/perf/tests/shell/coresight/deterministic.sh | 72 +++++++ .../tests/shell/coresight/memcpy_thread/.gitignore | 1 - .../tests/shell/coresight/memcpy_thread/Makefile | 33 --- .../shell/coresight/memcpy_thread/memcpy_thread.c | 80 ------- .../tests/shell/coresight/memcpy_thread_16k_10.sh | 22 -- .../perf/tests/shell/coresight/raw_dump_stress.sh | 65 ++++++ .../shell/{ => coresight}/test_arm_coresight.sh | 43 ++-- .../{ => coresight}/test_arm_coresight_disasm.sh | 23 +- .../tests/shell/coresight/thread_loop/.gitignore | 1 - .../tests/shell/coresight/thread_loop/Makefile | 33 --- .../shell/coresight/thread_loop/thread_loop.c | 85 -------- .../shell/coresight/thread_loop_check_tid_10.sh | 23 -- .../shell/coresight/thread_loop_check_tid_2.sh | 23 -- .../shell/coresight/unroll_loop_thread/.gitignore | 1 - .../shell/coresight/unroll_loop_thread/Makefile | 33 --- .../unroll_loop_thread/unroll_loop_thread.c | 75 ------- .../tests/shell/coresight/unroll_loop_thread_10.sh | 22 -- tools/perf/tests/shell/lib/coresight.sh | 134 ------------ tools/perf/tests/tests.h | 3 + tools/perf/tests/workloads/Build | 4 + tools/perf/tests/workloads/context_switch_loop.c | 110 ++++++++++ tools/perf/tests/workloads/deterministic.c | 39 ++++ tools/perf/tests/workloads/named_threads.c | 109 ++++++++++ tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 21 +- tools/perf/util/cs-etm.c | 236 ++++++++++++--------- tools/perf/util/cs-etm.h | 8 +- 40 files changed, 926 insertions(+), 942 deletions(-) --- base-commit: 351a37f2fda4db668cff8ba12f2992d73dccdaea change-id: 20260515-james-cs-context-tracking-fix-754998bae7ed Best regards, -- James Clark <james.clark(a)linaro.org>

3 months, 2 weeks

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