linux-kernel - [tip:perf/core] perf tools: Use 64-bit shifts with (TSC) time conversion

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Date:	Tue, 8 Mar 2016 02:31:37 -0800
From:	tip-bot for Adrian Hunter <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	eranian@...gle.com, jolsa@...hat.com, hpa@...or.com,
	acme@...hat.com, linux-kernel@...r.kernel.org, namhyung@...nel.org,
	alexander.shishkin@...ux.intel.com, adrian.hunter@...el.com,
	peterz@...radead.org, dsahern@...il.com, tglx@...utronix.de,
	mingo@...nel.org
Subject: [tip:perf/core] perf tools: Use 64-bit shifts with (TSC) time
 conversion

Commit-ID:  a23f96ee4d51ebd50b83ce0dbb5d04898fb8e3cb
Gitweb:     http://git.kernel.org/tip/a23f96ee4d51ebd50b83ce0dbb5d04898fb8e3cb
Author:     Adrian Hunter <adrian.hunter@...el.com>
AuthorDate: Mon, 7 Mar 2016 16:44:42 -0300
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Tue, 8 Mar 2016 10:11:18 +0100

perf tools: Use 64-bit shifts with (TSC) time conversion

Commit b9511cd761fa ("perf/x86: Fix time_shift in perf_event_mmap_page")
altered the time conversion algorithms documented in the perf_event.h
header file, to use 64-bit shifts.  That was done to make the code more
future-proof (i.e. some time in the future a 32-bit shift could be
allowed).  Reflect those changes in perf tools.

Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
Cc: Alexander Shishkin <alexander.shishkin@...ux.intel.com>
Cc: David Ahern <dsahern@...il.com>
Cc: Jiri Olsa <jolsa@...hat.com>
Cc: Namhyung Kim <namhyung@...nel.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Stephane Eranian <eranian@...gle.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Link: http://lkml.kernel.org/r/1457005856-6143-9-git-send-email-adrian.hunter@intel.com
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 tools/perf/arch/x86/tests/rdpmc.c | 2 +-
 tools/perf/util/tsc.c             | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/arch/x86/tests/rdpmc.c b/tools/perf/arch/x86/tests/rdpmc.c
index 7945462..72193f1 100644
--- a/tools/perf/arch/x86/tests/rdpmc.c
+++ b/tools/perf/arch/x86/tests/rdpmc.c
@@ -59,7 +59,7 @@ static u64 mmap_read_self(void *addr)
 		u64 quot, rem;
 
 		quot = (cyc >> time_shift);
-		rem = cyc & ((1 << time_shift) - 1);
+		rem = cyc & (((u64)1 << time_shift) - 1);
 		delta = time_offset + quot * time_mult +
 			((rem * time_mult) >> time_shift);
 
diff --git a/tools/perf/util/tsc.c b/tools/perf/util/tsc.c
index 4d4210d..1b74164 100644
--- a/tools/perf/util/tsc.c
+++ b/tools/perf/util/tsc.c
@@ -19,7 +19,7 @@ u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
 	u64 quot, rem;
 
 	quot = cyc >> tc->time_shift;
-	rem  = cyc & ((1 << tc->time_shift) - 1);
+	rem  = cyc & (((u64)1 << tc->time_shift) - 1);
 	return tc->time_zero + quot * tc->time_mult +
 	       ((rem * tc->time_mult) >> tc->time_shift);
 }