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[PATCH v2 2/4] perf util: Add host_is_bigendian to util.h

Ian Rogers posted 4 patches 2 years, 9 months ago
[PATCH v2 2/4] perf util: Add host_is_bigendian to util.h
Posted by Ian Rogers 2 years, 9 months ago 
Avoid libtraceevent dependency for tep_is_bigendian or trace-event.h
dependency for bigendian. Add a new host_is_bigendian to util.h, using
the compiler defined __BYTE_ORDER__ when available.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/code-reading.c    |  4 ++--
 tools/perf/tests/sample-parsing.c  |  4 ++--
 tools/perf/util/evsel.c            |  5 +----
 tools/perf/util/trace-event-info.c | 14 +++-----------
 tools/perf/util/trace-event-read.c |  3 ++-
 tools/perf/util/trace-event.h      |  2 --
 tools/perf/util/util.h             | 19 +++++++++++++++++++
 7 files changed, 29 insertions(+), 22 deletions(-)

diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 95feb6ef34a0..cb8cd09938d5 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -16,7 +16,6 @@
 #include "dso.h"
 #include "env.h"
 #include "parse-events.h"
-#include "trace-event.h"
 #include "evlist.h"
 #include "evsel.h"
 #include "thread_map.h"
@@ -28,6 +27,7 @@
 #include "util/mmap.h"
 #include "util/string2.h"
 #include "util/synthetic-events.h"
+#include "util/util.h"
 #include "thread.h"
 
 #include "tests.h"
@@ -79,7 +79,7 @@ static size_t read_objdump_chunk(const char **line, unsigned char **buf,
 	 * see disassemble_bytes() at binutils/objdump.c for details
 	 * how objdump chooses display endian)
 	 */
-	if (bytes_read > 1 && !bigendian()) {
+	if (bytes_read > 1 && !host_is_bigendian()) {
 		unsigned char *chunk_end = chunk_start + bytes_read - 1;
 		unsigned char tmp;
 
diff --git a/tools/perf/tests/sample-parsing.c b/tools/perf/tests/sample-parsing.c
index 20930dd48ee0..927c7f0cc4cc 100644
--- a/tools/perf/tests/sample-parsing.c
+++ b/tools/perf/tests/sample-parsing.c
@@ -13,7 +13,7 @@
 #include "evsel.h"
 #include "debug.h"
 #include "util/synthetic-events.h"
-#include "util/trace-event.h"
+#include "util/util.h"
 
 #include "tests.h"
 
@@ -117,7 +117,7 @@ static bool samples_same(const struct perf_sample *s1,
 		COMP(branch_stack->hw_idx);
 		for (i = 0; i < s1->branch_stack->nr; i++) {
 			if (needs_swap)
-				return ((tep_is_bigendian()) ?
+				return ((host_is_bigendian()) ?
 					(FLAG(s2).value == BS_EXPECTED_BE) :
 					(FLAG(s2).value == BS_EXPECTED_LE));
 			else
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 45f4f08399ae..0f617359a82f 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2320,11 +2320,8 @@ u64 evsel__bitfield_swap_branch_flags(u64 value)
 	 * as it has variable bit-field sizes. Instead the
 	 * macro takes the bit-field position/size,
 	 * swaps it based on the host endianness.
-	 *
-	 * tep_is_bigendian() is used here instead of
-	 * bigendian() to avoid python test fails.
 	 */
-	if (tep_is_bigendian()) {
+	if (host_is_bigendian()) {
 		new_val = bitfield_swap(value, 0, 1);
 		new_val |= bitfield_swap(value, 1, 1);
 		new_val |= bitfield_swap(value, 2, 1);
diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index 892c323b4ac9..c24b3a15e319 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -26,6 +26,7 @@
 #include <api/fs/tracing_path.h>
 #include "evsel.h"
 #include "debug.h"
+#include "util.h"
 
 #define VERSION "0.6"
 #define MAX_EVENT_LENGTH 512
@@ -38,15 +39,6 @@ struct tracepoint_path {
 	struct tracepoint_path *next;
 };
 
-int bigendian(void)
-{
-	unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
-	unsigned int *ptr;
-
-	ptr = (unsigned int *)(void *)str;
-	return *ptr == 0x01020304;
-}
-
 /* unfortunately, you can not stat debugfs or proc files for size */
 static int record_file(const char *file, ssize_t hdr_sz)
 {
@@ -79,7 +71,7 @@ static int record_file(const char *file, ssize_t hdr_sz)
 
 	/* ugh, handle big-endian hdr_size == 4 */
 	sizep = (char*)&size;
-	if (bigendian())
+	if (host_is_bigendian())
 		sizep += sizeof(u64) - hdr_sz;
 
 	if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0) {
@@ -564,7 +556,7 @@ static int tracing_data_header(void)
 		return -1;
 
 	/* save endian */
-	if (bigendian())
+	if (host_is_bigendian())
 		buf[0] = 1;
 	else
 		buf[0] = 0;
diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
index 8a01af783310..43146a4ce2fb 100644
--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c
@@ -17,6 +17,7 @@
 
 #include "trace-event.h"
 #include "debug.h"
+#include "util.h"
 
 static int input_fd;
 
@@ -414,7 +415,7 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
 		return -1;
 	}
 	file_bigendian = buf[0];
-	host_bigendian = bigendian();
+	host_bigendian = host_is_bigendian() ? 1 : 0;
 
 	if (trace_event__init(tevent)) {
 		pr_debug("trace_event__init failed");
diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h
index 640981105788..8f39f5bcb2c2 100644
--- a/tools/perf/util/trace-event.h
+++ b/tools/perf/util/trace-event.h
@@ -27,8 +27,6 @@ trace_event__tp_format(const char *sys, const char *name);
 
 struct tep_event *trace_event__tp_format_id(int id);
 
-int bigendian(void);
-
 void event_format__fprintf(struct tep_event *event,
 			   int cpu, void *data, int size, FILE *fp);
 
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 63cdab0e5314..87d418cb6792 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -94,4 +94,23 @@ int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x,
 		0;						\
 	})
 
+static inline bool host_is_bigendian(void)
+{
+#ifdef __BYTE_ORDER__
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+	return false;
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+	return true;
+#else
+#error "Unrecognized __BYTE_ORDER__"
+#endif
+#else
+	unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
+	unsigned int *ptr;
+
+	ptr = (unsigned int *)(void *)str;
+	return *ptr == 0x01020304;
+#endif
+}
+
 #endif /* __PERF_UTIL_H */
-- 
2.38.1.584.g0f3c55d4c2-goog
Re: [PATCH v2 2/4] perf util: Add host_is_bigendian to util.h
Posted by Namhyung Kim 2 years, 9 months ago 
On Tue, Nov 29, 2022 at 10:30 PM Ian Rogers <irogers@google.com> wrote:
>
> Avoid libtraceevent dependency for tep_is_bigendian or trace-event.h
> dependency for bigendian. Add a new host_is_bigendian to util.h, using
> the compiler defined __BYTE_ORDER__ when available.
>
> Signed-off-by: Ian Rogers <irogers@google.com>

Acked-by: Namhyung Kim <namhyung@kernel.org>

A nit below...

> ---
[SNIP]
> diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
> index 63cdab0e5314..87d418cb6792 100644
> --- a/tools/perf/util/util.h
> +++ b/tools/perf/util/util.h
> @@ -94,4 +94,23 @@ int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x,
>                 0;                                              \
>         })
>
> +static inline bool host_is_bigendian(void)
> +{
> +#ifdef __BYTE_ORDER__
> +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> +       return false;
> +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> +       return true;
> +#else
> +#error "Unrecognized __BYTE_ORDER__"
> +#endif
> +#else

It'd be nice if we could have a comment at least there's a nested
ifdef condition.  Like below?

#else  /* !__BYTE_ORDER__ */

Thanks,
Namhyung


> +       unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
> +       unsigned int *ptr;
> +
> +       ptr = (unsigned int *)(void *)str;
> +       return *ptr == 0x01020304;
> +#endif
> +}
> +
>  #endif /* __PERF_UTIL_H */
> --
> 2.38.1.584.g0f3c55d4c2-goog
>
Re: [PATCH v2 2/4] perf util: Add host_is_bigendian to util.h
Posted by Arnaldo Carvalho de Melo 2 years, 9 months ago 
Em Wed, Nov 30, 2022 at 10:52:35AM -0800, Namhyung Kim escreveu:
> On Tue, Nov 29, 2022 at 10:30 PM Ian Rogers <irogers@google.com> wrote:
> >
> > Avoid libtraceevent dependency for tep_is_bigendian or trace-event.h
> > dependency for bigendian. Add a new host_is_bigendian to util.h, using
> > the compiler defined __BYTE_ORDER__ when available.
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>
> 
> Acked-by: Namhyung Kim <namhyung@kernel.org>
> 
> A nit below...
> 
> > ---
> [SNIP]
> > diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
> > index 63cdab0e5314..87d418cb6792 100644
> > --- a/tools/perf/util/util.h
> > +++ b/tools/perf/util/util.h
> > @@ -94,4 +94,23 @@ int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x,
> >                 0;                                              \
> >         })
> >
> > +static inline bool host_is_bigendian(void)
> > +{
> > +#ifdef __BYTE_ORDER__
> > +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> > +       return false;
> > +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> > +       return true;
> > +#else
> > +#error "Unrecognized __BYTE_ORDER__"
> > +#endif
> > +#else
> 
> It'd be nice if we could have a comment at least there's a nested
> ifdef condition.  Like below?
> 
> #else  /* !__BYTE_ORDER__ */

Reasonable, added it and applied the first two patches in this series,
with your Acked-by, thanks.

- Arnaldo


diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 87d418cb67929576..a06c54ab85ee4506 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -104,7 +104,7 @@ static inline bool host_is_bigendian(void)
 #else
 #error "Unrecognized __BYTE_ORDER__"
 #endif
-#else
+#else /* !__BYTE_ORDER__ */
 	unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
 	unsigned int *ptr;

Patchew 2.1-devel-b67e4c2

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