mainlining shenanigans
Using .st_ctime clobbers the timestamp information in perf report header whenever any operation is done with the file. Even tar-ing and untar-ing the perf.data file (which preserves the file last modification timestamp) doesn't prevent that: [Michael@Diego tmp]$ ls -l perf.data -> -rw-------. 1 Michael Michael 169888 Dec 2 15:23 perf.data [Michael@Diego tmp]$ perf report --header-only # ======== -> # captured on : Mon Dec 2 15:23:42 2019 [...] [Michael@Diego tmp]$ tar c perf.data | xz > perf.data.tar.xz [Michael@Diego tmp]$ mkdir aaa [Michael@Diego tmp]$ cd aaa [Michael@Diego aaa]$ xzcat ../perf.data.tar.xz | tar x [Michael@Diego aaa]$ ls -l -a total 172 drwxrwxr-x. 2 Michael Michael 23 Jan 14 11:26 . drwxrwxr-x. 6 Michael Michael 4096 Jan 14 11:26 .. -> -rw-------. 1 Michael Michael 169888 Dec 2 15:23 perf.data [Michael@Diego aaa]$ perf report --header-only # ======== -> # captured on : Tue Jan 14 11:26:16 2020 [...] When using .st_mtime instead, correct information is printed: [Michael@Diego aaa]$ ~/acme/tools/perf/perf report --header-only # ======== -> # captured on : Mon Dec 2 15:23:42 2019 [...] Signed-off-by: Michael Petlan <mpetlan@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> LPU-Reference: 20200114104236.31555-1-mpetlan@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
---|---|---|
arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
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.