From: Andi Kleen <andi@firstfloor.org>
To: acme@kernel.org
Cc: jolsa@kernel.org, linux-kernel@vger.kernel.org,
linux-perf-users@vger.kernel.org, Andi Kleen <ak@linux.intel.com>,
Denis Bakhvalov <denis.bakhvalov@intel.com>
Subject: [PATCH 2/3] perf script: Fix off by one in brstackinsn IPC computation
Date: Thu, 11 Jul 2019 11:19:21 -0700 [thread overview]
Message-ID: <20190711181922.18765-2-andi@firstfloor.org> (raw)
In-Reply-To: <20190711181922.18765-1-andi@firstfloor.org>
From: Andi Kleen <ak@linux.intel.com>
When we hit the end of a program block, need to count the last instruction
too for the IPC computation. This caused large errors for small blocks.
% perf script -b ls / > /dev/null
Before:
% perf script -F +brstackinsn --xed
...
00007f94c9ac70d8 jz 0x7f94c9ac70e3 # PRED 3 cycles [36] 4.33 IPC
00007f94c9ac70e3 testb $0x20, 0x31d(%rbx)
00007f94c9ac70ea jnz 0x7f94c9ac70b0
00007f94c9ac70ec testb $0x8, 0x205ad(%rip)
00007f94c9ac70f3 jz 0x7f94c9ac6ff0 # PRED 1 cycles [37] 3.00 IPC
After:
% perf script -F +brstackinsn --xed
...
00007f94c9ac70d8 jz 0x7f94c9ac70e3 # PRED 3 cycles [15] 4.67 IPC
00007f94c9ac70e3 testb $0x20, 0x31d(%rbx)
00007f94c9ac70ea jnz 0x7f94c9ac70b0
00007f94c9ac70ec testb $0x8, 0x205ad(%rip)
00007f94c9ac70f3 jz 0x7f94c9ac6ff0 # PRED 1 cycles [16] 4.00 IPC
Suggested-by: Denis Bakhvalov <denis.bakhvalov@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
tools/perf/builtin-script.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 2f6232f1bfdc..9a63cb3442a9 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -1059,7 +1059,7 @@ static int perf_sample__fprintf_brstackinsn(struct perf_sample *sample,
printed += ip__fprintf_sym(ip, thread, x.cpumode, x.cpu, &lastsym, attr, fp);
if (ip == end) {
- printed += ip__fprintf_jump(ip, &br->entries[i], &x, buffer + off, len - off, insn, fp,
+ printed += ip__fprintf_jump(ip, &br->entries[i], &x, buffer + off, len - off, ++insn, fp,
&total_cycles);
if (PRINT_FIELD(SRCCODE))
printed += print_srccode(thread, x.cpumode, ip);
--
2.20.1
next prev parent reply other threads:[~2019-07-11 18:19 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-11 18:19 [PATCH 1/3] perf script: Fix --max-blocks man page description Andi Kleen
2019-07-11 18:19 ` Andi Kleen [this message]
2019-07-16 18:44 ` [PATCH 2/3] perf script: Fix off by one in brstackinsn IPC computation Arnaldo Carvalho de Melo
2019-07-23 21:47 ` [tip:perf/urgent] " tip-bot for Andi Kleen
2019-07-11 18:19 ` [PATCH 3/3] perf script: Improve man page description of metrics Andi Kleen
2019-07-16 18:45 ` Arnaldo Carvalho de Melo
2019-07-23 21:47 ` [tip:perf/urgent] " tip-bot for Andi Kleen
2019-07-16 18:43 ` [PATCH 1/3] perf script: Fix --max-blocks man page description Arnaldo Carvalho de Melo
2019-07-23 21:46 ` [tip:perf/urgent] " tip-bot for Andi Kleen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190711181922.18765-2-andi@firstfloor.org \
--to=andi@firstfloor.org \
--cc=acme@kernel.org \
--cc=ak@linux.intel.com \
--cc=denis.bakhvalov@intel.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).