41477acf09
So that we can figure out the real size of the struct and also be able to tell if callchains may be present in this histogram entry. Since we can't always guarantee that from hist_entry->hists we can use hists_to_evsel, to then look at evsel->attr.sample_type for PERF_SAMPLE_CALLCHAIN, like with the 'perf c2c' tool, that uses plain 'struct hists' instances, we need another way of deciding if a specific hist_entry instance has callchains associated with it, i.e. if its hist_entry->callchain[0] has space allocated for. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: https://lkml.kernel.org/n/tip-ptvndealxs1k7myluvu9flnq@git.kernel.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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.