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From: Riccardo Mancini <rickyman7@gmail.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>,
	Namhyung Kim <namhyung@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Mark Rutland <mark.rutland@arm.com>, Jiri Olsa <jolsa@redhat.com>,
	linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
	Riccardo Mancini <rickyman7@gmail.com>
Subject: [RFC PATCH v1 02/37] libperf cpumap: improve max function
Date: Sat, 21 Aug 2021 11:19:08 +0200	[thread overview]
Message-ID: <fb79f02e7b86ea8044d563adb1e9890c906f982f.1629490974.git.rickyman7@gmail.com> (raw)
In-Reply-To: <cover.1629490974.git.rickyman7@gmail.com>

From commit 7074674e7338863e ("perf cpumap: Maintain cpumaps ordered and
without dups"), perf_cpu_map elements are sorted in ascending order.

This patch improves the perf_cpu_map__max function by returning the last
element.

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
---
 tools/lib/perf/cpumap.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
index fb633272be3aaed9..80e03b2f0c60cce7 100644
--- a/tools/lib/perf/cpumap.c
+++ b/tools/lib/perf/cpumap.c
@@ -284,14 +284,10 @@ int perf_cpu_map__idx(struct perf_cpu_map *cpus, int cpu)
 
 int perf_cpu_map__max(struct perf_cpu_map *map)
 {
-	int i, max = -1;
-
-	for (i = 0; i < map->nr; i++) {
-		if (map->map[i] > max)
-			max = map->map[i];
-	}
-
-	return max;
+	if (map->nr > 0)
+		return map->map[map->nr-1];
+	else
+		return -1;
 }
 
 /*
-- 
2.31.1


  parent reply	other threads:[~2021-08-21  9:19 UTC|newest]

Thread overview: 63+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-21  9:19 [RFC PATCH v1 00/37] perf: use workqueue for evlist operations Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 01/37] libperf cpumap: improve idx function Riccardo Mancini
2021-08-31 18:46   ` Arnaldo Carvalho de Melo
2021-10-08 14:29   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` Riccardo Mancini [this message]
2021-08-31 18:47   ` [RFC PATCH v1 02/37] libperf cpumap: improve max function Arnaldo Carvalho de Melo
2021-08-31 19:16     ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 03/37] perf evlist: replace evsel__cpu_iter* functions with evsel__find_cpu Riccardo Mancini
2021-10-08 14:38   ` [RFC PATCH v1 03/37] perf evlist: replace evsel__cpu_iter* functions with evsel__find_cpu() Arnaldo Carvalho de Melo
2021-12-11  0:20   ` [RFC PATCH v1 03/37] perf evlist: replace evsel__cpu_iter* functions with evsel__find_cpu Ian Rogers
2021-08-21  9:19 ` [RFC PATCH v1 04/37] perf util: add mmap_cpu_mask__duplicate function Riccardo Mancini
2021-08-31 19:21   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 05/37] perf util/mmap: add missing bitops.h header Riccardo Mancini
2021-08-31 19:22   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 06/37] perf workqueue: add affinities to threadpool Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 07/37] perf workqueue: add support for setting affinities to workers Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 08/37] perf workqueue: add method to execute work on specific CPU Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 09/37] perf python: add workqueue dependency Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 10/37] perf evlist: add multithreading helper Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 11/37] perf evlist: add multithreading to evlist__disable Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 12/37] perf evlist: add multithreading to evlist__enable Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 13/37] perf evlist: add multithreading to evlist__close Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 14/37] perf evsel: remove retry_sample_id goto label Riccardo Mancini
2021-08-31 19:25   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 15/37] perf evsel: separate open preparation from open itself Riccardo Mancini
2021-08-31 19:27   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 16/37] perf evsel: save open flags in evsel Riccardo Mancini
2021-08-31 19:31   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 17/37] perf evsel: separate missing feature disabling from evsel__open_cpu Riccardo Mancini
2021-08-31 19:35   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 18/37] perf evsel: add evsel__prepare_open function Riccardo Mancini
2021-08-31 19:36   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 19/37] perf evsel: separate missing feature detection from evsel__open_cpu Riccardo Mancini
2021-08-31 19:39   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 20/37] perf evsel: separate rlimit increase " Riccardo Mancini
2021-08-31 19:41   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 21/37] perf evsel: move ignore_missing_thread to fallback code Riccardo Mancini
2021-08-31 19:44   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 22/37] perf evsel: move test_attr__open to success path in evsel__open_cpu Riccardo Mancini
2021-08-31 19:47   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 23/37] perf evsel: move bpf_counter__install_pe " Riccardo Mancini
2021-08-31 19:50   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 24/37] perf evsel: handle precise_ip fallback " Riccardo Mancini
2021-08-31 19:52   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 25/37] perf evsel: move event open in evsel__open_cpu to separate function Riccardo Mancini
2021-08-31 19:54   ` Arnaldo Carvalho de Melo
2021-09-03 21:52     ` Riccardo Mancini
2021-09-11 19:10       ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 26/37] perf evsel: add evsel__open_per_cpu_no_fallback function Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 27/37] perf evlist: add evlist__for_each_entry_from macro Riccardo Mancini
2021-08-31 20:06   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 28/37] perf evlist: add multithreading to evlist__open Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 29/37] perf evlist: add custom fallback " Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 30/37] perf record: use evlist__open_custom Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 31/37] tools lib/subcmd: add OPT_UINTEGER_OPTARG option type Riccardo Mancini
2021-08-31 18:44   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 32/37] perf record: add --threads option Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 33/37] perf record: pin threads to monitored cpus if enough threads available Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 34/37] perf record: apply multithreading in init and fini phases Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 35/37] perf test/evlist-open-close: add multithreading Riccardo Mancini
2021-08-21  9:19 ` [RFC PATCH v1 36/37] perf test/evlist-open-close: use inline func to convert timeval to usec Riccardo Mancini
2021-10-08 14:46   ` Arnaldo Carvalho de Melo
2021-08-21  9:19 ` [RFC PATCH v1 37/37] perf test/evlist-open-close: add detailed output mode Riccardo Mancini

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