From 75e906c9601aee73b88d6e6dc02371f8c3ca24d7 Mon Sep 17 00:00:00 2001
From: Don Zickus <dzickus@redhat.com>
Date: Fri, 23 May 2014 18:41:23 +0200
Subject: perf report: Add mem-mode documentation to report command
Add mem-mode sorting types and mem-mode itself to perf-report documentation.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1400526833-141779-5-git-send-email-dzickus@redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/Documentation/perf-report.txt | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
(limited to 'tools/perf/Documentation/perf-report.txt')
diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index cefdf430d1b4..00fbfb6d7f14 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -117,6 +117,21 @@ OPTIONS
By default, every sort keys not specified in -F will be appended
automatically.
+ If --mem-mode option is used, following sort keys are also available
+ (incompatible with --branch-stack):
+ symbol_daddr, dso_daddr, locked, tlb, mem, snoop.
+
+ - symbol_daddr: name of data symbol being executed on at the time of sample
+ - dso_daddr: name of library or module containing the data being executed
+ on at the time of sample
+ - locked: whether the bus was locked at the time of sample
+ - tlb: type of tlb access for the data at the time of sample
+ - mem: type of memory access for the data at the time of sample
+ - snoop: type of snoop (if any) for the data at the time of sample
+
+ And default sort keys are changed to local_weight, mem, sym, dso,
+ symbol_daddr, dso_daddr, snoop, tlb, locked, see '--mem-mode'.
+
-p::
--parent=<regex>::
A regex filter to identify parent. The parent is a caller of this
@@ -260,6 +275,13 @@ OPTIONS
Demangle symbol names to human readable form. It's enabled by default,
disable with --no-demangle.
+--mem-mode::
+ Use the data addresses of samples in addition to instruction addresses
+ to build the histograms. To generate meaningful output, the perf.data
+ file must have been obtained using perf record -d -W and using a
+ special event -e cpu/mem-loads/ or -e cpu/mem-stores/. See
+ 'perf mem' for simpler access.
+
--percent-limit::
Do not show entries which have an overhead under that percent.
(Default: 0).
--
cgit v1.2.2
From 9b32ba71ba905b90610fc2aad77cb98a373c5624 Mon Sep 17 00:00:00 2001
From: Don Zickus <dzickus@redhat.com>
Date: Sun, 1 Jun 2014 15:38:29 +0200
Subject: perf tools: Add dcacheline sort
In perf's 'mem-mode', one can get access to a whole bunch of details specific to a
particular sample instruction. A bunch of those details relate to the data
address.
One interesting thing you can do with data addresses is to convert them into a unique
cacheline they belong too. Organizing these data cachelines into similar groups and sorting
them can reveal cache contention.
This patch creates an alogorithm based on various sample details that can help group
entries together into data cachelines and allows 'perf report' to sort on it.
The algorithm relies on having proper mmap2 support in the kernel to help determine
if the memory map the data address belongs to is private to a pid or globally shared.
The alogortithm is as follows:
o group cpumodes together
o group entries with discovered maps together
o sort on major, minor, inode and inode generation numbers
o if userspace anon, then sort on pid
o sort on cachelines based on data addresses
The 'dcacheline' sort option in 'perf report' only works in 'mem-mode'.
Sample output:
#
# Samples: 206 of event 'cpu/mem-loads/pp'
# Total weight : 2534
# Sort order : dcacheline,pid
#
# Overhead Samples Data Cacheline Command: Pid
# ........ ............ ...................................................................... ..................
#
13.22% 1 [k] 0xffff88042f08ebc0 swapper: 0
9.27% 1 [k] 0xffff88082e8cea80 swapper: 0
3.59% 2 [k] 0xffffffff819ba180 swapper: 0
0.32% 1 [k] arch_trigger_all_cpu_backtrace_handler_na.23901+0xffffffffffffffe0 swapper: 0
0.32% 1 [k] timekeeper_seq+0xfffffffffffffff8 swapper: 0
Note: Added a '+1' to symlen size in hists__calc_col_len to prevent the next column
from prematurely tabbing over and mis-aligning. Not sure what the problem is.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1401208087-181977-8-git-send-email-dzickus@redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/Documentation/perf-report.txt | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
(limited to 'tools/perf/Documentation/perf-report.txt')
diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 00fbfb6d7f14..d2b59af62bc0 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -119,7 +119,7 @@ OPTIONS
If --mem-mode option is used, following sort keys are also available
(incompatible with --branch-stack):
- symbol_daddr, dso_daddr, locked, tlb, mem, snoop.
+ symbol_daddr, dso_daddr, locked, tlb, mem, snoop, dcacheline.
- symbol_daddr: name of data symbol being executed on at the time of sample
- dso_daddr: name of library or module containing the data being executed
@@ -128,6 +128,7 @@ OPTIONS
- tlb: type of tlb access for the data at the time of sample
- mem: type of memory access for the data at the time of sample
- snoop: type of snoop (if any) for the data at the time of sample
+ - dcacheline: the cacheline the data address is on at the time of sample
And default sort keys are changed to local_weight, mem, sym, dso,
symbol_daddr, dso_daddr, snoop, tlb, locked, see '--mem-mode'.
--
cgit v1.2.2