kernel/git/next/linux-next.git/tools/perf/util/session.c, branch master

perf regs: Enable dumping of SIMD registers

2026-09-14T18:34:43+00:00

Support dumping of SIMD registers with the new PERF_SAMPLE_REGS_ABI_SIMD ABI. Currently, the XMM, YMM, ZMM, OPMASK, eGPRs, and SSP registers on x86 platforms are supported with the PERF_SAMPLE_REGS_ABI_SIMD ABI. An example of the raw format output is displayed below. Example: $perf record -e cycles:p -Iax,bx,r8,r16,r31,ssp,xmm,ymm,zmm,opmask ./test $perf report -D ... ... 3342715685845 0x3afe8 [0xbc8]: PERF_RECORD_SAMPLE(IP, 0x1): 27776/27776: 0xffffffff91d7c18f period: 10000 addr: 0 ... intr regs: mask 0x18001010003 ABI 64-bit SIMD .... AX 0xffffed102de1a606 .... BX 0xffffed102de1a606 .... R8 0x0000000000000001 .... R16 0x0000000000000000 .... R31 0x0000000000000000 .... SSP 0x0000000000000000 ... SIMD ABI nr_vectors 32 vector_qwords 8 nr_pred 8 pred_qwords 1 .... ZMM[0][0] 0x616c2f656d6f682f .... ZMM[0][1] 0x696c2f7265737562 .... ZMM[0][2] 0x0000000000000000 .... ZMM[0][3] 0x0000000000000000 .... ZMM[0][4] 0x0000000000000000 .... ZMM[0][5] 0x0000000000000000 .... ZMM[0][6] 0x0000000000000000 .... ZMM[0][7] 0x0000000000000000 .... ZMM[1][0] 0x702f636578656269 .... ZMM[1][1] 0x65726f632d667265 .... ZMM[1][2] 0x0000000000000000 .... ZMM[1][3] 0x0000000000000000 .... ZMM[1][4] 0x0000000000000000 .... ZMM[1][5] 0x0000000000000000 .... ZMM[1][6] 0x0000000000000000 .... ZMM[1][7] 0x0000000000000000 ... ... .... ZMM[31][0] 0x0000000000000000 .... ZMM[31][1] 0x0000000000000000 .... ZMM[31][2] 0x0000000000000000 .... ZMM[31][3] 0x0000000000000000 .... ZMM[31][4] 0x0000000000000000 .... ZMM[31][5] 0x0000000000000000 .... ZMM[31][6] 0x0000000000000000 .... ZMM[31][7] 0x0000000000000000 .... OPMASK[0] 0x0000000000100221 .... OPMASK[1] 0x0000000000000020 .... OPMASK[2] 0x000000007fffffff .... OPMASK[3] 0x0000000000000000 .... OPMASK[4] 0x0000000000000000 .... OPMASK[5] 0x0000000000000000 .... OPMASK[6] 0x0000000000000000 .... OPMASK[7] 0x0000000000000000 ... ... Co-developed-by: Kan Liang Signed-off-by: Kan Liang Signed-off-by: Dapeng Mi Signed-off-by: Arnaldo Carvalho de Melo

perf regs: Support x86 eGPRs/SSP sampling

2026-09-14T18:33:33+00:00

Add support for sampling x86 extended GP registers (R16-R31) and the shadow stack pointer (SSP) register. The original XMM registers space in sample_regs_user/sample_regs_intr is reclaimed to represent the eGPRs and SSP when SIMD registers sampling is supported with the new SIMD sampling fields in the perf_event_attr structure. This necessitates a way to distinguish which register layout is used for the sample_regs_user/sample_regs_intr bitmap. To address this, a new "abi" argument is added to the helpers perf_intr_reg_mask(), perf_user_reg_mask(), and perf_reg_name(). When "abi & PERF_SAMPLE_REGS_ABI_SIMD" is true, it indicates the eGPRs and SSP layout is represented; otherwise, the legacy XMM registers are represented. Please note that PERF_SAMPLE_REGS_ABI_SIMD is set by default on platforms that support SIMD register sampling, even when no eGPR or SSP register is requested (for example, -Iax). As a result, sample_regs_intr and sample_regs_usr always use the new GPR layout on platforms with SIMD register sampling support. The patch only supports eGPRs and SSP sampling, the complete SIMD registers sampling would be supported in the next patch. Signed-off-by: Dapeng Mi Signed-off-by: Arnaldo Carvalho de Melo

perf headers: Sync perf_event.h/perf_regs.h with the kernel headers

2026-09-14T18:32:52+00:00

Sync the UAPI header changes of supporting SIMD/eGPRs/SSP sampling into corresponding tools UAPI headers. Additionally, support the new introduced perf_event_attr fields in the perf_event_attr__fprintf and perf_event__attr_swap() helpers, and add sanity check for the new introduced __reserved_4 field in perf_attr_check(). Co-developed-by: Kan Liang Signed-off-by: Kan Liang Signed-off-by: Dapeng Mi Signed-off-by: Arnaldo Carvalho de Melo

perf util: Add missed fields in _attrfprintf() and attr_swap()

2026-09-14T18:32:26+00:00

Some new introduced perf_event_attr fields, like config3 and config4, are forgotten to add into perf_event_attr__fprintf() and perf_event__attr_swap() helpers. Add these missed fields into these 2 helpers. The aux_action is an exception. aux_action aliases bitfields (e.g. aux_start_paused) in a union. Bitfields and plain u32 fields follow different endian rules, so both views cannot be swapped correctly at the same time. Leave aux_action unswapped until the ABI is represented in a byte-order-safe form. Signed-off-by: Dapeng Mi Signed-off-by: Arnaldo Carvalho de Melo

perf python: Refactor and add accessors to sample event

2026-06-30T17:17:14+00:00

Add common evsel field for events and move sample specific fields to only be present in sample events. Add accessors for sample events. Ensure offsets are within the bounds of the event. Allocate just enough memory for the copied event, don't make the maximum event size each time. Assisted-by: Gemini:gemini-3.1-pro-preview Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alice Rogers Cc: Dapeng Mi Cc: Ingo Molnar Cc: James Clark Cc: Leo Yan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf python: Use evsel in sample in pyrf_event

2026-06-30T17:17:12+00:00

Avoid a duplicated evsel by using the one in sample. Add evsel__get/put to the evsel in perf_sample. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alice Rogers Cc: Dapeng Mi Cc: Ingo Molnar Cc: James Clark Cc: Leo Yan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf evlist: Add reference count checking

2026-06-30T17:17:11+00:00

Now the evlist is reference counted, add reference count checking so that gets and puts are paired and easy to debug. Reference count checking is documented here: https://perfwiki.github.io/main/reference-count-checking/ This large patch is adding accessors to evlist functions and switching to their use. There was some minor renaming as evlist__mmap is now an accessor to the mmap variable, and the original evlist__mmap is renamed to evlist__do_mmap. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alice Rogers Cc: Dapeng Mi Cc: Ingo Molnar Cc: James Clark Cc: Leo Yan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf evsel: Add reference count

2026-06-30T17:17:11+00:00

As with evlist this a no-op for most of the perf tool. The reference count is set to 1 at allocation, the put will see the 1, decrement it and perform the delete. The purpose for adding the reference count is for the python code. Prior to this change the python code would clone evsels, but this has issues if events are opened, etc. leading to assertion failures. With a reference count the same evsel can be used and the reference count incremented for the python usage. To not change the python evsel API getset functions are added for the evsel members, no set function is provided for size as it doesn't make sense to alter this. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alice Rogers Cc: Dapeng Mi Cc: Ingo Molnar Cc: James Clark Cc: Leo Yan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf evlist: Add reference count

2026-06-30T17:17:10+00:00

This a no-op for most of the perf tool. The reference count is set to 1 at allocation, the put will see the 1, decrement it and perform the delete. The purpose for adding the reference count is for the python code. Prior to this change the python code would clone evlists, but this has issues if events are opened, etc. This change adds a reference count for the evlists and a later change will add it to evsels. The combination is needed for the python code to operate correctly (not hit asserts in the evsel clone), but the changes are broken apart for the sake of smaller patches. Assisted-by: Gemini:gemini-3.1-pro-preview Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alice Rogers Cc: Dapeng Mi Cc: Ingo Molnar Cc: James Clark Cc: Leo Yan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf machine: Propagate machine__init() error to callers

2026-06-17T12:21:03+00:00

machine__init() always returns 0 even when memory allocation fails, because commit 81f981d7ec43ed93 ("perf machine: Free root_dir in machine__init() error path") introduced 'int err = -ENOMEM' and an error cleanup path but left the final 'return 0' instead of 'return err'. Fix by returning err, check the return value in __machine__new_host() which was ignoring it, and change machines__init() from void to int so it too can propagate the error to perf_session__new(), aslr_tool__init() and test callers. The error cleanup also used zfree(&machine->kmaps), but kmaps is a refcounted maps structure — use maps__zput() to properly drop the reference, matching machine__exit(). Move dsos__init() and threads__init() before the first fallible allocation (maps__new) so that machine__exit() is safe to call on any machine struct that machine__init() touched, even on early failure. Fixes: 81f981d7ec43ed93 ("perf machine: Free root_dir in machine__init() error path") Reported-by: sashiko-bot Cc: Ian Rogers Cc: Jiri Olsa Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Arnaldo Carvalho de Melo

kernel/git/next/linux-next.git/tools/perf/util/session.c, branch master

perf regs: Enable dumping of SIMD registers

perf regs: Support x86 eGPRs/SSP sampling

perf headers: Sync perf_event.h/perf_regs.h with the kernel headers

perf util: Add missed fields in _attr__fprintf() and __attr_swap()

perf python: Refactor and add accessors to sample event

perf python: Use evsel in sample in pyrf_event

perf evlist: Add reference count checking

perf evsel: Add reference count

perf evlist: Add reference count

perf machine: Propagate machine__init() error to callers

perf util: Add missed fields in _attrfprintf() and attr_swap()