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2e21bcf051
Add a flag to the 'perf mem' data struct to signal that a request caused a cache-to-cache transfer of a line from a peer of the requestor and wasn't sourced from a lower cache level. The line being moved from one peer cache to another has latency and performance implications. On Arm64 Neoverse systems the data source can indicate a cache-to-cache transfer but not if the line is dirty or clean, so instead of overloading HITM define a new flag that indicates this type of transfer. Committer notes: This really is not syncing with the kernel since the patch to the kernel wasn't merged. But we're going ahead of this as it seems trivial and is just a matter of the perf kernel maintainers to give their ack or for us to find another way of expressing this in the perf records synthesized in userspace from the ARM64 hardware traces. Reviewed-by: Leo Yan <leo.yan@linaro.org> Signed-off-by: Ali Saidi <alisaidi@amazon.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: German Gomez <german.gomez@arm.com> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Ian Rogers <irogers@google.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: Kajol Jain <kjain@linux.ibm.com> Cc: Like Xu <likexu@tencent.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Timothy Hayes <timothy.hayes@arm.com> Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20220811062451.435810-2-leo.yan@linaro.org Signed-off-by: Leo Yan <leo.yan@linaro.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.