kernel.git/tools/perf/builtin-kvm.c, branch master

perf session: Add e_flags to the e_machine helper

2026-02-03T21:01:27Z

Allow e_flags as well as e_machine to be computed using the e_machine helper. This isn't currently used, the argument is always NULL, but it will be used for a new header feature. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf kvm: Wire up e_machine

2026-02-03T21:01:27Z

Pass the e_machine to the kvm functions so that they aren't just wired to EM_HOST. In the case of a session move some setup until the session is created. As the session isn't fully running the default EM_HOST is returned as no e_machine can be found in a running machine. This is, however, some marginal progress to cross platform support. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf kvm stat: Remove use of the arch directory

2026-02-03T21:01:27Z

`perf kvm stat` supports record and report options. By using the arch directory a report for a different machine type cannot be supported. Move the kvm-stat code out of the arch directory and into util/kvm-stat-arch following the pattern of perf-regs and dwarf-regs. Avoid duplicate symbols by renaming functions to have the architecture name within them. For global variables, wrap them in an architecture specific function. Selecting the architecture to use with `perf kvm stat` is selected by EM_HOST, ie no different than before the change. Later the ELF machine can be determined from the session or a header feature (ie EM_HOST at the time of the record). The build and #define HAVE_KVM_STAT_SUPPORT is now redundant so remove across Makefiles and in the build. Opportunistically constify architectural structs and arrays. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf kvm: Fix debug assertion

2025-12-03T19:07:19Z

There are 2 slots left for kvm_add_default_arch_event, fix the assertion so that debug builds don't fail the assert and to agree with the comment. Fixes: 45ff39f6e70aa55d0 ("perf tools kvm: Fix the potential out of range memory access issue") Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf tools kvm: Use "cycles" to sample guest for "kvm top" on Intel

2025-10-02T18:31:55Z

As same reason with previous patch, use "cyles" instead of "cycles:P" event by default to sample guest for "perf kvm top" command on Intel platforms. Fixes: cf8e55fe50df0c02 ("KVM: x86/pmu: Expose CPUIDs feature bits PDCM, DS, DTES64") Reported-by: Kevin Tian Signed-off-by: Dapeng Mi Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Kan Liang Cc: Like Xu Cc: Paolo Bonzini Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf tools kvm: Use "cycles" to sample guest for "kvm record" on Intel

2025-10-02T18:31:39Z

After KVM supports PEBS for guest on Intel platforms (https://lore.kernel.org/all/20220411101946.20262-1-likexu@tencent.com/), host loses the capability to sample guest with PEBS since all PEBS related MSRs are switched to guest value after vm-entry, like IA32_DS_AREA MSR is switched to guest GVA at vm-entry. This would lead to "perf kvm record" fails to sample guest on Intel platforms since "cycles:P" event is used to sample guest by default as below case shows. sudo perf kvm record -a ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.787 MB perf.data.guest ] So to ensure guest record can be sampled successfully, use "cycles" instead of "cycles:P" to sample guest record by default on Intel platforms. With this patch, the guest record can be sampled successfully. sudo perf kvm record -a ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.783 MB perf.data.guest (23 samples) ] Fixes: cf8e55fe50df0c02 ("KVM: x86/pmu: Expose CPUIDs feature bits PDCM, DS, DTES64") Reported-by: Kevin Tian Signed-off-by: Dapeng Mi Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Kan Liang Cc: Like Xu Cc: Paolo Bonzini Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf tools kvm: Fix the potential out of range memory access issue

2025-10-02T18:31:00Z

kvm_add_default_arch_event() helper may add 2 extra options but it directly modifies the original argv[] array. This may cause out of range memory access. Fix this issue. Signed-off-by: Dapeng Mi Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Kan Liang Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf tools kvm: Add missed memory allocation check and free

2025-10-02T18:30:21Z

Current code allocates rec_argv[] array, but doesn't check if the allocation is successful and explicitly free the rec_argv[] array. Add them back. Signed-off-by: Dapeng Mi Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Kan Liang Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf session: Add accessor for session->header.env

2025-07-25T17:37:56Z

The perf_env from the header in the session is frequently accessed, add an accessor function rather than access directly. Cache the value to avoid repeated calls. No behavioral change. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-10-irogers@google.com Signed-off-by: Namhyung Kim

perf target: Remove uid from target

2025-06-09T18:18:18Z

Gathering threads with a uid by scanning /proc is inherently racy leading to perf_event_open failures that quit perf. All users of the functionality now use BPF filters, so remove uid and uid_str from target. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250604174545.2853620-10-irogers@google.com Signed-off-by: Namhyung Kim