mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-03 19:26:01 -04:00
a1a8bed32d
Current --branch-history LBR annotation displays confused data. For
example, each cycles report is duplicated on both "from" and "to"
entries.
For example:
perf report --branch-history --no-children --stdio
--2.32%--main div.c:39 (COND_BWD CROSS_2M predicted:49.7% cycles:1)
main div.c:44 (predicted:49.7% cycles:1)
main div.c:42 (RET CROSS_2M cycles:2)
compute_flag div.c:28 (cycles:2)
compute_flag div.c:27 (RET CROSS_2M cycles:1)
rand rand.c:28 (cycles:1)
rand rand.c:28 (RET CROSS_2M cycles:1)
__random random.c:298 (cycles:1)
__random random.c:297 (COND_BWD CROSS_2M cycles:1)
__random random.c:295 (cycles:1)
__random random.c:295 (COND_BWD CROSS_2M cycles:1)
__random random.c:295 (cycles:1)
__random random.c:295 (RET CROSS_2M cycles:9)
The cycles should be tagged only on the "from". It's for the code block
that ends with "from", not for "to".
Another issue is the "predicted:49.7%" is duplicated too (tag on both
"from" and "to").
This patch tags the branch type/flag on "to" and tag the cycles on
"from".
For example:
--2.32%--main div.c:39 (COND_BWD CROSS_2M predicted:49.7%)
main div.c:44 (cycles:1)
main div.c:42 (RET CROSS_2M)
compute_flag div.c:28 (cycles:2)
compute_flag div.c:27 (RET CROSS_2M)
rand rand.c:28 (cycles:1)
rand rand.c:28 (RET CROSS_2M)
__random random.c:298 (cycles:1)
__random random.c:297 (COND_BWD CROSS_2M)
__random random.c:295 (cycles:1)
__random random.c:295 (COND_BWD CROSS_2M)
__random random.c:295 (cycles:1)
__random random.c:295 (RET CROSS_2M)
|
--2.23%--__random_r random_r.c:392 (cycles:9)
In this example, The "main div.c:39 (COND_BWD CROSS_2M predicted:49.7%)"
is "to" of branch and "main div.c:44 (cycles:1)" is "from" of branch.
It should be easier for understanding than before.
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1500894547-18411-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.