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From: Ian Rogers <irogers@google.com>
To: "Yury Norov" <yury.norov@gmail.com>,
	"Rasmus Villemoes" <linux@rasmusvillemoes.dk>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Ingo Molnar" <mingo@redhat.com>,
	"Arnaldo Carvalho de Melo" <acme@kernel.org>,
	"Namhyung Kim" <namhyung@kernel.org>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"Alexander Shishkin" <alexander.shishkin@linux.intel.com>,
	"Jiri Olsa" <jolsa@kernel.org>, "Ian Rogers" <irogers@google.com>,
	"Adrian Hunter" <adrian.hunter@intel.com>,
	"Kan Liang" <kan.liang@linux.intel.com>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Darren Hart" <dvhart@infradead.org>,
	"Davidlohr Bueso" <dave@stgolabs.net>,
	"André Almeida" <andrealmeid@igalia.com>,
	"John Garry" <john.g.garry@oracle.com>,
	"Will Deacon" <will@kernel.org>,
	"James Clark" <james.clark@linaro.org>,
	"Mike Leach" <mike.leach@linaro.org>,
	"Leo Yan" <leo.yan@linux.dev>,
	"Yicong Yang" <yangyicong@hisilicon.com>,
	"Jonathan Cameron" <jonathan.cameron@huawei.com>,
	"Nathan Chancellor" <nathan@kernel.org>,
	"Bill Wendling" <morbo@google.com>,
	"Justin Stitt" <justinstitt@google.com>,
	"Josh Poimboeuf" <jpoimboe@kernel.org>,
	"Al Viro" <viro@zeniv.linux.org.uk>,
	"Kyle Meyer" <kyle.meyer@hpe.com>,
	"Ben Gainey" <ben.gainey@arm.com>,
	"Athira Rajeev" <atrajeev@linux.vnet.ibm.com>,
	"Kajol Jain" <kjain@linux.ibm.com>,
	"Aditya Gupta" <adityag@linux.ibm.com>,
	"Eder Zulian" <ezulian@redhat.com>,
	"Dapeng Mi" <dapeng1.mi@linux.intel.com>,
	"Kuan-Wei Chiu" <visitorckw@gmail.com>,
	"He Zhe" <zhe.he@windriver.com>,
	"Dirk Gouders" <dirk@gouders.net>,
	"Brian Geffon" <bgeffon@google.com>,
	"Ravi Bangoria" <ravi.bangoria@amd.com>,
	"Howard Chu" <howardchu95@gmail.com>,
	"Charlie Jenkins" <charlie@rivosinc.com>,
	"Colin Ian King" <colin.i.king@gmail.com>,
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	"Jann Horn" <jannh@google.com>,
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	"Yang Jihong" <yangjihong@bytedance.com>,
	"Dmitry Vyukov" <dvyukov@google.com>,
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	"Junhao He" <hejunhao3@huawei.com>,
	"Masami Hiramatsu (Google)" <mhiramat@kernel.org>,
	"Xu Yang" <xu.yang_2@nxp.com>,
	"Steve Clevenger" <scclevenger@os.amperecomputing.com>,
	"Zixian Cai" <fzczx123@gmail.com>,
	"Stephen Brennan" <stephen.s.brennan@oracle.com>,
	"Yujie Liu" <yujie.liu@intel.com>,
	linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev
Subject: [PATCH v1 13/48] perf trace-event: Silence -Wshorten-64-to-32 warnings
Date: Tue,  1 Apr 2025 11:23:11 -0700	[thread overview]
Message-ID: <20250401182347.3422199-14-irogers@google.com> (raw)
In-Reply-To: <20250401182347.3422199-1-irogers@google.com>

The clang warning -Wshorten-64-to-32 can be useful to catch
inadvertent truncation. In some instances this truncation can lead to
changing the sign of a result, for example, truncation to return an
int to fit a sort routine. Silence the warning by making the implicit
truncation explicit.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/python.c                      |  4 ++--
 .../scripting-engines/trace-event-python.c    | 13 ++++++-----
 tools/perf/util/trace-event-info.c            |  3 ++-
 tools/perf/util/trace-event-parse.c           |  2 +-
 tools/perf/util/trace-event-read.c            | 23 +++++++++----------
 tools/perf/util/trace-event-scripting.c       |  2 +-
 6 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index f3c05da25b4a..f55b2b7435ad 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -305,7 +305,7 @@ tracepoint_field(const struct pyrf_event *pe, struct tep_format_field *field)
 		len    = field->size;
 		if (field->flags & TEP_FIELD_IS_DYNAMIC) {
 			val     = tep_read_number(pevent, data + offset, len);
-			offset  = val;
+			offset  = (unsigned int)val;
 			len     = offset >> 16;
 			offset &= 0xffff;
 			if (tep_field_is_relative(field->flags))
@@ -599,7 +599,7 @@ static PyObject *pyrf_thread_map__item(PyObject *obj, Py_ssize_t i)
 	if (i >= perf_thread_map__nr(pthreads->threads))
 		return NULL;
 
-	return Py_BuildValue("i", perf_thread_map__pid(pthreads->threads, i));
+	return Py_BuildValue("i", (int)perf_thread_map__pid(pthreads->threads, (int)i));
 }
 
 static PySequenceMethods pyrf_thread_map__sequence_methods = {
diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index 520729e78965..547eeb45a832 100644
--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c
@@ -713,9 +713,10 @@ static void set_sample_datasrc_in_dict(PyObject *dict,
 			_PyUnicode_FromString(decode));
 }
 
-static void regs_map(struct regs_dump *regs, uint64_t mask, const char *arch, char *bf, int size)
+static void regs_map(struct regs_dump *regs, uint64_t mask, const char *arch, char *bf, size_t size)
 {
-	unsigned int i = 0, r;
+	unsigned int i = 0;
+	u64 r;
 	int printed = 0;
 
 	bf[0] = 0;
@@ -731,7 +732,7 @@ static void regs_map(struct regs_dump *regs, uint64_t mask, const char *arch, ch
 
 		printed += scnprintf(bf + printed, size - printed,
 				     "%5s:0x%" PRIx64 " ",
-				     perf_reg_name(r, arch), val);
+				     perf_reg_name((int)r, arch), val);
 	}
 }
 
@@ -744,7 +745,7 @@ static int set_regs_in_dict(PyObject *dict,
 	struct perf_event_attr *attr = &evsel->core.attr;
 	const char *arch = perf_env__arch(evsel__env(evsel));
 
-	int size = (__sw_hweight64(attr->sample_regs_intr) * MAX_REG_SIZE) + 1;
+	size_t size = (__sw_hweight64(attr->sample_regs_intr) * MAX_REG_SIZE) + 1;
 	char *bf = NULL;
 
 	if (sample->intr_regs) {
@@ -957,7 +958,7 @@ static void python_process_tracepoint(struct perf_sample *sample,
 		Py_FatalError(handler_name);
 	}
 
-	pid = raw_field_value(event, "common_pid", data);
+	pid = (int)raw_field_value(event, "common_pid", data);
 
 	sprintf(handler_name, "%s__%s", event->system, event->name);
 
@@ -1017,7 +1018,7 @@ static void python_process_tracepoint(struct perf_sample *sample,
 			if (field->flags & TEP_FIELD_IS_DYNAMIC) {
 				val     = tep_read_number(scripting_context->pevent,
 							  data + offset, len);
-				offset  = val;
+				offset  = (unsigned int)val;
 				len     = offset >> 16;
 				offset &= 0xffff;
 				if (tep_field_is_relative(field->flags))
diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index c8755679281e..0f012890ff21 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -45,7 +45,8 @@ static int record_file(const char *file, ssize_t hdr_sz)
 	unsigned long long size = 0;
 	char buf[BUFSIZ], *sizep;
 	off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
-	int r, fd;
+	int fd;
+	ssize_t r;
 	int err = -EIO;
 
 	fd = open(file, O_RDONLY);
diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 9c015fc2bcfb..982cbbc57168 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -34,7 +34,7 @@ static int get_common_field(struct scripting_context *context,
 		*size = field->size;
 	}
 
-	return tep_read_number(pevent, context->event_data + *offset, *size);
+	return (int)tep_read_number(pevent, context->event_data + *offset, *size);
 }
 
 int common_lock_depth(struct scripting_context *context)
diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
index ecbbb93f0185..78a3b3801d69 100644
--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c
@@ -25,18 +25,18 @@ static int input_fd;
 static ssize_t trace_data_size;
 static bool repipe;
 
-static int __do_read(int fd, void *buf, int size)
+static int __do_read(int fd, void *buf, size_t size)
 {
-	int rsize = size;
+	int rsize = (int)size;
 
 	while (size) {
-		int ret = read(fd, buf, size);
+		ssize_t ret = read(fd, buf, size);
 
 		if (ret <= 0)
 			return -1;
 
 		if (repipe) {
-			int retw = write(STDOUT_FILENO, buf, ret);
+			ssize_t retw = write(STDOUT_FILENO, buf, ret);
 
 			if (retw <= 0 || retw != ret) {
 				pr_debug("repiping input file");
@@ -51,14 +51,13 @@ static int __do_read(int fd, void *buf, int size)
 	return rsize;
 }
 
-static int do_read(void *data, int size)
+static int do_read(void *data, size_t size)
 {
 	int r;
 
 	r = __do_read(input_fd, data, size);
 	if (r <= 0) {
-		pr_debug("reading input file (size expected=%d received=%d)",
-			 size, r);
+		pr_debug("reading input file (size expected=%zd received=%d)", size, r);
 		return -1;
 	}
 
@@ -68,10 +67,10 @@ static int do_read(void *data, int size)
 }
 
 /* If it fails, the next read will report it */
-static void skip(int size)
+static void skip(unsigned long long size)
 {
 	char buf[BUFSIZ];
-	int r;
+	unsigned long long r;
 
 	while (size) {
 		r = size > BUFSIZ ? BUFSIZ : size;
@@ -86,7 +85,7 @@ static unsigned int read4(struct tep_handle *pevent)
 
 	if (do_read(&data, 4) < 0)
 		return 0;
-	return tep_read_number(pevent, &data, 4);
+	return (unsigned int)tep_read_number(pevent, &data, 4);
 }
 
 static unsigned long long read8(struct tep_handle *pevent)
@@ -119,7 +118,7 @@ static char *read_string(void)
 		}
 
 		if (repipe) {
-			int retw = write(STDOUT_FILENO, &c, 1);
+			ssize_t retw = write(STDOUT_FILENO, &c, 1);
 
 			if (retw <= 0 || retw != r) {
 				pr_debug("repiping input file string");
@@ -365,7 +364,7 @@ static int read_saved_cmdline(struct tep_handle *pevent)
 	}
 	buf[ret] = '\0';
 
-	parse_saved_cmdline(pevent, buf, size);
+	parse_saved_cmdline(pevent, buf, (unsigned int)size);
 	ret = 0;
 out:
 	free(buf);
diff --git a/tools/perf/util/trace-event-scripting.c b/tools/perf/util/trace-event-scripting.c
index 72abb28b7b5a..fb1fa227c98e 100644
--- a/tools/perf/util/trace-event-scripting.c
+++ b/tools/perf/util/trace-event-scripting.c
@@ -422,5 +422,5 @@ int perf_sample__sprintf_flags(u32 flags, char *str, size_t sz)
 	if (pos < sz)
 		str[pos] = 0;
 
-	return pos;
+	return (int)pos;
 }
-- 
2.49.0.504.g3bcea36a83-goog


  parent reply	other threads:[~2025-04-01 18:25 UTC|newest]

Thread overview: 70+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-01 18:22 [PATCH v1 00/48] Perf build support for -Wshorten-64-to-32 Ian Rogers
2025-04-01 18:22 ` [PATCH v1 01/48] perf build: Avoid building libbpf/bpftool with LIBBPF_DYNAMIC Ian Rogers
2025-04-01 18:23 ` [PATCH v1 02/48] tools headers: Silence -Wshorten-64-to-32 warnings Ian Rogers
2025-04-03 14:08   ` Yury Norov
2025-04-03 14:26     ` Yury Norov
2025-04-03 14:52       ` Ian Rogers
2025-04-03 15:23         ` Yury Norov
2025-04-03 15:45           ` Ian Rogers
2025-04-03 18:12             ` Ian Rogers
2025-04-03 18:18               ` Yury Norov
2025-04-03 18:25                 ` Ian Rogers
2025-04-01 18:23 ` [PATCH v1 03/48] arm64: cputype: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 04/48] x86/insn: " Ian Rogers
2025-04-02 11:10   ` Eder Zulian
2025-04-01 18:23 ` [PATCH v1 05/48] tools lib: " Ian Rogers
2025-04-03 14:19   ` Yury Norov
2025-04-01 18:23 ` [PATCH v1 06/48] libperf: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 07/48] tools subcmd: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 08/48] perf bench: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 09/48] perf tests: " Ian Rogers
2025-04-02 14:35   ` Leo Yan
2025-04-02 15:42     ` Ian Rogers
2025-04-02 16:38       ` Leo Yan
2025-04-02 16:53         ` Ian Rogers
2025-04-03  4:53           ` Namhyung Kim
2025-04-03 15:20             ` Ian Rogers
2025-04-28 11:10               ` Leo Yan
2025-04-28 16:29                 ` Ian Rogers
2025-04-29  9:53                   ` Leo Yan
2025-04-02 22:01         ` David Laight
2025-04-02 22:32           ` Ian Rogers
2025-04-01 18:23 ` [PATCH v1 10/48] perf arch x86: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 11/48] perf arm-spe: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 12/48] perf trace: " Ian Rogers
2025-04-01 18:23 ` Ian Rogers [this message]
2025-04-01 18:23 ` [PATCH v1 14/48] perf jvmti: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 15/48] perf pmu: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 16/48] perf annotate powerpc: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 17/48] perf s390: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 18/48] perf cs-etm: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 19/48] perf stat: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 20/48] perf dlfilter: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 21/48] perf demangle: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 22/48] perf ui: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 23/48] perf annotate: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 24/48] perf report: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 25/48] perf help: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 26/48] perf hisi-ptt: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 27/48] perf probe: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 28/48] perf kwork: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 29/48] perf buildid: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 30/48] perf lock: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 31/48] perf mem: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 32/48] perf script: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 33/48] perf evlist: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 34/48] perf bpf_counter: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 35/48] perf ftrace: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 36/48] perf record: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 37/48] perf inject: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 38/48] perf sched: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 39/48] perf timechart: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 40/48] perf list: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 41/48] perf kvm: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 42/48] perf diff: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 43/48] perf daemon: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 44/48] perf zlib: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 45/48] perf symbol: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 46/48] perf util: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 47/48] perf hashmap: " Ian Rogers
2025-04-01 18:23 ` [PATCH v1 48/48] perf: " Ian Rogers

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