summaryrefslogtreecommitdiff
path: root/crypto/tcrypt.c
diff options
context:
space:
mode:
authorKan Liang <kan.liang@linux.intel.com>2022-07-18 09:43:10 -0700
committerArnaldo Carvalho de Melo <acme@redhat.com>2022-07-25 12:28:00 -0300
commitbc2373a58aacb241bf135b9a7452a1499d0d457e (patch)
treee4f7f6694618cea87bd00a6f2a5251b463b91a0d /crypto/tcrypt.c
parent9fe9b252c7c022df8e503435e778f15c04dfa3bf (diff)
downloadlwn-bc2373a58aacb241bf135b9a7452a1499d0d457e.tar.gz
lwn-bc2373a58aacb241bf135b9a7452a1499d0d457e.zip
perf tsc: Add arch TSC frequency information
The TSC frequency information is required for the event metrics with the literal, system_tsc_freq. For the newer Intel platform, the TSC frequency information can be retrieved from the CPUID leaf 0x15. If the TSC frequency information isn't present the /proc/cpuinfo approach is used. Refactor cpuid() for this use. Note, the previous stack pushing/popping approach was broken on x86-64 that has stack red zones that would be clobbered. Committer testing: Before: $ perf record sleep 0.0001 [ perf record: Woken up 1 times to write data ] $ perf report --header-only |& grep cpuid # cpuid : AuthenticAMD,25,33,0 $ After the patch: $ perf record sleep 0.0001 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.002 MB perf.data (8 samples) ] $ perf report --header-only |& grep cpuid # cpuid : AuthenticAMD,25,33,0 $ Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Caleb Biggers <caleb.biggers@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.garry@huawei.com> Cc: Kshipra Bopardikar <kshipra.bopardikar@intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Perry Taylor <perry.taylor@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com> Link: https://lore.kernel.org/r/20220718164312.3994191-2-irogers@google.com Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'crypto/tcrypt.c')
0 files changed, 0 insertions, 0 deletions