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perf tools: Update strbuf to remove xrealloc

RFC PATCH Superseded Masami Hiramatsu 2 participants 11 messages Apr 29, 2016 perf events

v1 of 3 Superseded Latest is v3 →

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#0 lore raw

cover perf tools: Update strbuf to remove xrealloc

Hi Arnaldo,

This patch series does refactoring strbuf and xrealloc related code to remove xrealloc since it can call die() to exit immediately when it hits any error. Instead of that, it should return error code to the caller so that the caller can handle its error.

Thus, at first, this changes the strbuf APIs to return error code instead of die() immediately. And then changing API callers according to the following rules.
- Check the return value of strbuf APIs and handle errors and,
- If the caller returns an error code (errno), it returns the return value of strbuf APIs.
- If the caller just return -1 or NULl in error case, it also returns -1 or NULL in case of strbuf error.
- If the caller can call die() directly, it also call die() in case of strbuf error.
- Error checking patches are splitted for each subcommand, since it will help review.

This also removes xrealloc and ALLOC_GROW from libperf, so that no one use it anymore.

This series actually depends on the series of SDT support patches which I've sent an hour ago. It is also able to change this not to depend on it easily. Please ask me if you'd like so.

Thank you,

---

Masami Hiramatsu (8):
perf: Rewrite strbuf not to die
perf probe: Check the return value of strbuf APIs
perf help: Make check_emacsclient_version to check strbuf APIs
perf: Make alias handler to check return value of strbuf perf header: Make topology checkers to check return value of strbuf perf pmu: Make pmu_formats_string to check return value of strbuf perf help: Do not use ALLOC_GROW in add_cmd_list
perf tools: Remove xrealloc and ALLOC_GROW

 tools/perf/builtin-help.c          |   18 ++--
 tools/perf/perf.c                  |    8 +-
 tools/perf/util/Build              |    1 
 tools/perf/util/cache.h            |   19 ----
 tools/perf/util/dwarf-aux.c        |   50 +++++------
 tools/perf/util/header.c           |   31 ++++---
 tools/perf/util/help-unknown-cmd.c |   30 +++++-
 tools/perf/util/pmu.c              |   10 +-
 tools/perf/util/probe-event.c      |  167 +++++++++++++++++++++---------------
 tools/perf/util/probe-finder.c     |   30 ++++--
 tools/perf/util/quote.c            |   36 ++++----
 tools/perf/util/quote.h            |    2 
 tools/perf/util/strbuf.c           |   93 ++++++++++++++------
 tools/perf/util/strbuf.h           |   25 +++--
 tools/perf/util/util.h             |    6 -
 tools/perf/util/wrapper.c          |   29 ------
 16 files changed, 302 insertions(+), 253 deletions(-)
 delete mode 100644 tools/perf/util/wrapper.c

--
Masami Hiramatsu

#1 lore raw

RFC PATCH 1/8 perf: Rewrite strbuf not to die

Rewrite strbuf implementation not to use die() nor xrealloc(). Instead of die, now most of the API returns error code or 0 if succeeded.

---
 tools/perf/util/strbuf.c |   93 +++++++++++++++++++++++++++++++++-------------
 tools/perf/util/strbuf.h |   25 +++++++-----
 2 files changed, 82 insertions(+), 36 deletions(-)
tools/perf/util/strbuf.c +67 -26
index 8fb7329..a98bb60 100644
@@ -1,3 +1,4 @@
+#include "debug.h"
 #include "cache.h"
 #include <linux/kernel.h>
 
@@ -17,12 +18,13 @@ int prefixcmp(const char *str, const char *prefix)
  */
 char strbuf_slopbuf[1];
 
-void strbuf_init(struct strbuf *sb, ssize_t hint)
+int strbuf_init(struct strbuf *sb, ssize_t hint)
 {
 	sb->alloc = sb->len = 0;
 	sb->buf = strbuf_slopbuf;
 	if (hint)
-		strbuf_grow(sb, hint);
+		return strbuf_grow(sb, hint);
+	return 0;
 }
 
 void strbuf_release(struct strbuf *sb)
@@ -42,67 +44,104 @@ char *strbuf_detach(struct strbuf *sb, size_t *sz)
 	return res;
 }
 
-void strbuf_grow(struct strbuf *sb, size_t extra)
+int strbuf_grow(struct strbuf *sb, size_t extra)
 {
-	if (sb->len + extra + 1 <= sb->len)
-		die("you want to use way too much memory");
-	if (!sb->alloc)
-		sb->buf = NULL;
-	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
+	char *buf;
+	size_t nr = sb->len + extra + 1;
+
+	if (nr < sb->alloc)
+		return 0;
+
+	if (nr <= sb->len)
+		return -E2BIG;
+
+	if (alloc_nr(sb->alloc) > nr)
+		nr = alloc_nr(sb->alloc);
+
+	buf = malloc(nr * sizeof(*buf));
+	if (!buf)
+		return -ENOMEM;
+
+	if (sb->alloc) {
+		memcpy(buf, sb->buf, sb->alloc);
+		free(sb->buf);
+	}
+	sb->buf = buf;
+	sb->alloc = nr;
+	return 0;
 }
 
-void strbuf_addch(struct strbuf *sb, int c)
+int strbuf_addch(struct strbuf *sb, int c)
 {
-	strbuf_grow(sb, 1);
+	int ret = strbuf_grow(sb, 1);
+	if (ret)
+		return ret;
+
 	sb->buf[sb->len++] = c;
 	sb->buf[sb->len] = '\0';
+	return 0;
 }
 
-void strbuf_add(struct strbuf *sb, const void *data, size_t len)
+int strbuf_add(struct strbuf *sb, const void *data, size_t len)
 {
-	strbuf_grow(sb, len);
+	int ret = strbuf_grow(sb, len);
+	if (ret)
+		return ret;
+
 	memcpy(sb->buf + sb->len, data, len);
-	strbuf_setlen(sb, sb->len + len);
+	return strbuf_setlen(sb, sb->len + len);
 }
 
-static void strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap)
+static int strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap)
 {
-	int len;
+	int len, ret;
 	va_list ap_saved;
 
-	if (!strbuf_avail(sb))
-		strbuf_grow(sb, 64);
+	if (!strbuf_avail(sb)) {
+		ret = strbuf_grow(sb, 64);
+		if (ret)
+			return ret;
+	}
 
 	va_copy(ap_saved, ap);
 	len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 	if (len < 0)
-		die("your vsnprintf is broken");
+		return len;
 	if (len > strbuf_avail(sb)) {
-		strbuf_grow(sb, len);
+		ret = strbuf_grow(sb, len);
+		if (ret)
+			return ret;
 		len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap_saved);
 		va_end(ap_saved);
 		if (len > strbuf_avail(sb)) {
-			die("this should not happen, your vsnprintf is broken");
+			pr_debug("this should not happen, your vsnprintf is broken");
+			return -EINVAL;
 		}
 	}
-	strbuf_setlen(sb, sb->len + len);
+	return strbuf_setlen(sb, sb->len + len);
 }
 
-void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
+int strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 {
 	va_list ap;
+	int ret;
 
 	va_start(ap, fmt);
-	strbuf_addv(sb, fmt, ap);
+	ret = strbuf_addv(sb, fmt, ap);
 	va_end(ap);
+	return ret;
 }
 
 ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
 {
 	size_t oldlen = sb->len;
 	size_t oldalloc = sb->alloc;
+	int ret;
+
+	ret = strbuf_grow(sb, hint ? hint : 8192);
+	if (ret)
+		return ret;
 
-	strbuf_grow(sb, hint ? hint : 8192);
 	for (;;) {
 		ssize_t cnt;
 
@@ -112,12 +151,14 @@ ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
 				strbuf_release(sb);
 			else
 				strbuf_setlen(sb, oldlen);
-			return -1;
+			return cnt;
 		}
 		if (!cnt)
 			break;
 		sb->len += cnt;
-		strbuf_grow(sb, 8192);
+		ret = strbuf_grow(sb, 8192);
+		if (ret)
+			return ret;
 	}
 
 	sb->buf[sb->len] = '\0';
tools/perf/util/strbuf.h +15 -10
index ab9be0fb..54b4092 100644
@@ -51,7 +51,7 @@ struct strbuf {
 #define STRBUF_INIT  { 0, 0, strbuf_slopbuf }
 
 /*----- strbuf life cycle -----*/
-void strbuf_init(struct strbuf *buf, ssize_t hint);
+int strbuf_init(struct strbuf *buf, ssize_t hint);
 void strbuf_release(struct strbuf *buf);
 char *strbuf_detach(struct strbuf *buf, size_t *);
 
@@ -60,26 +60,31 @@ static inline ssize_t strbuf_avail(const struct strbuf *sb) {
 	return sb->alloc ? sb->alloc - sb->len - 1 : 0;
 }
 
-void strbuf_grow(struct strbuf *buf, size_t);
+int strbuf_grow(struct strbuf *buf, size_t);
 
-static inline void strbuf_setlen(struct strbuf *sb, size_t len) {
-	if (!sb->alloc)
-		strbuf_grow(sb, 0);
+static inline int strbuf_setlen(struct strbuf *sb, size_t len) {
+	int ret;
+	if (!sb->alloc) {
+		ret = strbuf_grow(sb, 0);
+		if (ret)
+			return ret;
+	}
 	assert(len < sb->alloc);
 	sb->len = len;
 	sb->buf[len] = '\0';
+	return 0;
 }
 
 /*----- add data in your buffer -----*/
-void strbuf_addch(struct strbuf *sb, int c);
+int strbuf_addch(struct strbuf *sb, int c);
 
-void strbuf_add(struct strbuf *buf, const void *, size_t);
-static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
-	strbuf_add(sb, s, strlen(s));
+int strbuf_add(struct strbuf *buf, const void *, size_t);
+static inline int strbuf_addstr(struct strbuf *sb, const char *s) {
+	return strbuf_add(sb, s, strlen(s));
 }
 
 __attribute__((format(printf,2,3)))
-void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
+int strbuf_addf(struct strbuf *sb, const char *fmt, ...);
 
 /* XXX: if read fails, any partial read is undone */
 ssize_t strbuf_read(struct strbuf *, int fd, ssize_t hint);
#2 lore raw

RFC PATCH 2/8 perf probe: Check the return value of strbuf APIs

In reply to Masami Hiramatsu

Check the return value of strbuf APIs in perf-probe related code, so that it can handle errors in strbuf.

---
 tools/perf/util/dwarf-aux.c    |   50 +++++-------
 tools/perf/util/probe-event.c  |  167 +++++++++++++++++++++++-----------------
 tools/perf/util/probe-finder.c |   30 ++++---
 3 files changed, 137 insertions(+), 110 deletions(-)
tools/perf/util/dwarf-aux.c +21 -29
index aea189b..8c8b4c1 100644
@@ -915,8 +915,7 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		tmp = "*";
 	else if (tag == DW_TAG_subroutine_type) {
 		/* Function pointer */
-		strbuf_add(buf, "(function_type)", 15);
-		return 0;
+		return strbuf_add(buf, "(function_type)", 15);
 	} else {
 		if (!dwarf_diename(&type))
 			return -ENOENT;
@@ -927,14 +926,10 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		else if (tag == DW_TAG_enumeration_type)
 			tmp = "enum ";
 		/* Write a base name */
-		strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
-		return 0;
+		return strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
 	}
 	ret = die_get_typename(&type, buf);
-	if (ret == 0)
-		strbuf_addstr(buf, tmp);
-
-	return ret;
+	return ret ? ret : strbuf_addstr(buf, tmp);
 }
 
 /**
@@ -951,12 +946,10 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
 	ret = die_get_typename(vr_die, buf);
 	if (ret < 0) {
 		pr_debug("Failed to get type, make it unknown.\n");
-		strbuf_add(buf, " (unknown_type)", 14);
+		ret = strbuf_add(buf, " (unknown_type)", 14);
 	}
 
-	strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
-
-	return 0;
+	return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
 }
 
 #ifdef HAVE_DWARF_GETLOCATIONS
@@ -998,23 +991,23 @@ static int die_get_var_innermost_scope(Dwarf_Die *sp_die, Dwarf_Die *vr_die,
 		goto out;
 	}
 
-	while ((offset = dwarf_ranges(&scopes[1], offset, &base,
-				&start, &end)) > 0) {
+	while (!ret && (offset = dwarf_ranges(&scopes[1], offset, &base,
+					&start, &end)) > 0) {
 		start -= entry;
 		end -= entry;
 
 		if (first) {
-			strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
-				name, start, end);
+			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
+					  name, start, end);
 			first = false;
 		} else {
-			strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
-				start, end);
+			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
+					  start, end);
 		}
 	}
 
-	if (!first)
-		strbuf_add(buf, "]>", 2);
+	if (!ret && !first)
+		ret = strbuf_add(buf, "]>", 2);
 
 out:
 	free(scopes);
@@ -1054,9 +1047,8 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
 	if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
 		return -EINVAL;
 
-	while ((offset = dwarf_getlocations(
-				&attr, offset, &base,
-				&start, &end, &op, &nops)) > 0) {
+	while (!ret && (offset = dwarf_getlocations(&attr, offset, &base,
+					&start, &end, &op, &nops)) > 0) {
 		if (start == 0) {
 			/* Single Location Descriptions */
 			ret = die_get_var_innermost_scope(sp_die, vr_die, buf);
@@ -1067,17 +1059,17 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
 		start -= entry;
 		end -= entry;
 		if (first) {
-			strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
-				name, start, end);
+			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
+					  name, start, end);
 			first = false;
 		} else {
-			strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
-				start, end);
+			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
+					  start, end);
 		}
 	}
 
-	if (!first)
-		strbuf_add(buf, "]>", 2);
+	if (!ret && !first)
+		ret = strbuf_add(buf, "]>", 2);
 
 	return ret;
 }
tools/perf/util/probe-event.c +98 -69

312 lines not on this page · raw message

tools/perf/util/probe-finder.c +18 -12
index 9f68875..1259839 100644
@@ -1294,6 +1294,7 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 {
 	struct available_var_finder *af = data;
 	struct variable_list *vl;
+	struct strbuf buf = STRBUF_INIT;
 	int tag, ret;
 
 	vl = &af->vls[af->nvls - 1];
@@ -1307,25 +1308,26 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 		if (ret == 0 || ret == -ERANGE) {
 			int ret2;
 			bool externs = !af->child;
-			struct strbuf buf;
 
-			strbuf_init(&buf, 64);
+			if (strbuf_init(&buf, 64) < 0)
+				goto error;
 
 			if (probe_conf.show_location_range) {
-				if (!externs) {
-					if (ret)
-						strbuf_add(&buf, "[INV]\t", 6);
-					else
-						strbuf_add(&buf, "[VAL]\t", 6);
-				} else
-					strbuf_add(&buf, "[EXT]\t", 6);
+				if (!externs)
+					ret2 = strbuf_add(&buf,
+						ret ? "[INV]\t" : "[VAL]\t", 6);
+				else
+					ret2 = strbuf_add(&buf, "[EXT]\t", 6);
+				if (ret2)
+					goto error;
 			}
 
 			ret2 = die_get_varname(die_mem, &buf);
 
 			if (!ret2 && probe_conf.show_location_range &&
 				!externs) {
-				strbuf_addch(&buf, '\t');
+				if (strbuf_addch(&buf, '\t') < 0)
+					goto error;
 				ret2 = die_get_var_range(&af->pf.sp_die,
 							die_mem, &buf);
 			}
@@ -1334,8 +1336,8 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 			if (ret2 == 0) {
 				strlist__add(vl->vars,
 					strbuf_detach(&buf, NULL));
-			} else
-				strbuf_release(&buf);
+			}
+			strbuf_release(&buf);
 		}
 	}
 
@@ -1343,6 +1345,10 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 		return DIE_FIND_CB_CONTINUE;
 	else
 		return DIE_FIND_CB_SIBLING;
+error:
+	strbuf_release(&buf);
+	pr_debug("Error in strbuf\n");
+	return DIE_FIND_CB_END;
 }
 
 /* Add a found vars into available variables list */
#3 lore raw

RFC PATCH 3/8 perf help: Make check_emacsclient_version to check strbuf APIs

In reply to Masami Hiramatsu

Make check_emacsclient_version() to check the return value of strbuf APIs so that it can handle errors in strbuf.

---
 tools/perf/builtin-help.c |   18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)
tools/perf/builtin-help.c +10 -8
index bc1de9b..f9830c9 100644
@@ -61,6 +61,7 @@ static int check_emacsclient_version(void)
 	struct child_process ec_process;
 	const char *argv_ec[] = { "emacsclient", "--version", NULL };
 	int version;
+	int ret = -1;
 
 	/* emacsclient prints its version number on stderr */
 	memset(&ec_process, 0, sizeof(ec_process));
@@ -71,7 +72,10 @@ static int check_emacsclient_version(void)
 		fprintf(stderr, "Failed to start emacsclient.\n");
 		return -1;
 	}
-	strbuf_read(&buffer, ec_process.err, 20);
+	if (strbuf_read(&buffer, ec_process.err, 20) < 0) {
+		fprintf(stderr, "Failed to read emacsclient version\n");
+		goto out;
+	}
 	close(ec_process.err);
 
 	/*
@@ -82,8 +86,7 @@ static int check_emacsclient_version(void)
 
 	if (prefixcmp(buffer.buf, "emacsclient")) {
 		fprintf(stderr, "Failed to parse emacsclient version.\n");
-		strbuf_release(&buffer);
-		return -1;
+		goto out;
 	}
 
 	version = atoi(buffer.buf + strlen("emacsclient"));
@@ -92,12 +95,11 @@ static int check_emacsclient_version(void)
 		fprintf(stderr,
 			"emacsclient version '%d' too old (< 22).\n",
 			version);
-		strbuf_release(&buffer);
-		return -1;
-	}
-
+	} else
+		ret = 0;
+out:
 	strbuf_release(&buffer);
-	return 0;
+	return ret;
 }
 
 static void exec_woman_emacs(const char *path, const char *page)
#4 lore raw

RFC PATCH 4/8 perf: Make alias handler to check return value of strbuf

In reply to Masami Hiramatsu

Make alias handler and sq_quote_argv to check the return value of strbuf APIs.
In sq_quote_argv() calls die(), but this fix handles strbuf failure as a special case and returns to caller, since the caller - handle_alias() also has to check the return value of other strbuf APIs and those checks can be merged to one if() statement.

---
 tools/perf/perf.c       |    8 +++++---
 tools/perf/util/quote.c |   36 ++++++++++++++++++++----------------
 tools/perf/util/quote.h |    2 +-
 3 files changed, 26 insertions(+), 20 deletions(-)
tools/perf/perf.c +5 -3
index 83ffe7c..7970008 100644
@@ -309,9 +309,11 @@ static int handle_alias(int *argcp, const char ***argv)
 			if (*argcp > 1) {
 				struct strbuf buf;
 
-				strbuf_init(&buf, PATH_MAX);
-				strbuf_addstr(&buf, alias_string);
-				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
+				if (strbuf_init(&buf, PATH_MAX) < 0 ||
+				    strbuf_addstr(&buf, alias_string) < 0 ||
+				    sq_quote_argv(&buf, (*argv) + 1,
+						  PATH_MAX) < 0)
+					die("Failed to allocate memory.");
 				free(alias_string);
 				alias_string = buf.buf;
 			}
tools/perf/util/quote.c +20 -16
index 01f0324..c6d4ee2 100644
@@ -17,38 +17,42 @@ static inline int need_bs_quote(char c)
 	return (c == '\'' || c == '!');
 }
 
-static void sq_quote_buf(struct strbuf *dst, const char *src)
+static int sq_quote_buf(struct strbuf *dst, const char *src)
 {
 	char *to_free = NULL;
+	int ret;
 
 	if (dst->buf == src)
 		to_free = strbuf_detach(dst, NULL);
 
-	strbuf_addch(dst, '\'');
-	while (*src) {
+	ret = strbuf_addch(dst, '\'');
+	while (!ret && *src) {
 		size_t len = strcspn(src, "'!");
-		strbuf_add(dst, src, len);
+		ret = strbuf_add(dst, src, len);
 		src += len;
-		while (need_bs_quote(*src)) {
-			strbuf_addstr(dst, "'\\");
-			strbuf_addch(dst, *src++);
-			strbuf_addch(dst, '\'');
-		}
+		while (!ret && need_bs_quote(*src))
+			ret = strbuf_addf(dst, "'\\%c\'", *src++);
 	}
-	strbuf_addch(dst, '\'');
+	if (!ret)
+		ret = strbuf_addch(dst, '\'');
 	free(to_free);
+
+	return ret;
 }
 
-void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
+int sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
 {
-	int i;
+	int i, ret;
 
 	/* Copy into destination buffer. */
-	strbuf_grow(dst, 255);
-	for (i = 0; argv[i]; ++i) {
-		strbuf_addch(dst, ' ');
-		sq_quote_buf(dst, argv[i]);
+	ret = strbuf_grow(dst, 255);
+	for (i = 0; !ret && argv[i]; ++i) {
+		ret = strbuf_addch(dst, ' ');
+		if (ret)
+			break;
+		ret = sq_quote_buf(dst, argv[i]);
 		if (maxlen && dst->len > maxlen)
 			die("Too many or long arguments");
 	}
+	return ret;
 }
tools/perf/util/quote.h +1 -1
index 3340c9c..e1ec191 100644
@@ -24,6 +24,6 @@
  * sq_quote() in a real application.
  */
 
-void sq_quote_argv(struct strbuf *, const char **argv, size_t maxlen);
+int sq_quote_argv(struct strbuf *, const char **argv, size_t maxlen);
 
 #endif /* __PERF_QUOTE_H */
#5 lore raw

RFC PATCH 5/8 perf header: Make topology checkers to check return value of strbuf

In reply to Masami Hiramatsu

Make topology checkers to check the return value of strbuf APIs so that it can detect errors in it.

---
 tools/perf/util/header.c |   31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)
tools/perf/util/header.c +20 -11
index 90680ec..5ab74e4 100644
@@ -1819,7 +1819,8 @@ static int process_cpu_topology(struct perf_file_section *section,
 
 	ph->env.nr_sibling_cores = nr;
 	size += sizeof(u32);
-	strbuf_init(&sb, 128);
+	if (strbuf_init(&sb, 128) < 0)
+		goto free_cpu;
 
 	for (i = 0; i < nr; i++) {
 		str = do_read_string(fd, ph);
@@ -1827,7 +1828,8 @@ static int process_cpu_topology(struct perf_file_section *section,
 			goto error;
 
 		/* include a NULL character at the end */
-		strbuf_add(&sb, str, strlen(str) + 1);
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
 		size += string_size(str);
 		free(str);
 	}
@@ -1849,7 +1851,8 @@ static int process_cpu_topology(struct perf_file_section *section,
 			goto error;
 
 		/* include a NULL character at the end */
-		strbuf_add(&sb, str, strlen(str) + 1);
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
 		size += string_size(str);
 		free(str);
 	}
@@ -1907,7 +1910,7 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 	u32 nr, node, i;
 	char *str;
 	uint64_t mem_total, mem_free;
-	struct strbuf sb;
+	struct strbuf sb = STRBUF_INIT;
 
 	/* nr nodes */
 	ret = readn(fd, &nr, sizeof(nr));
@@ -1918,7 +1921,8 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 		nr = bswap_32(nr);
 
 	ph->env.nr_numa_nodes = nr;
-	strbuf_init(&sb, 256);
+	if (strbuf_init(&sb, 256) < 0)
+		goto error;
 
 	for (i = 0; i < nr; i++) {
 		/* node number */
@@ -1940,15 +1944,17 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 			mem_free = bswap_64(mem_free);
 		}
 
-		strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
-			    node, mem_total, mem_free);
+		if (strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
+				node, mem_total, mem_free) < 0)
+			goto error;
 
 		str = do_read_string(fd, ph);
 		if (!str)
 			goto error;
 
 		/* include a NULL character at the end */
-		strbuf_add(&sb, str, strlen(str) + 1);
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
 		free(str);
 	}
 	ph->env.numa_nodes = strbuf_detach(&sb, NULL);
@@ -1982,7 +1988,8 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
 	}
 
 	ph->env.nr_pmu_mappings = pmu_num;
-	strbuf_init(&sb, 128);
+	if (strbuf_init(&sb, 128) < 0)
+		return -1;
 
 	while (pmu_num) {
 		if (readn(fd, &type, sizeof(type)) != sizeof(type))
@@ -1994,9 +2001,11 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
 		if (!name)
 			goto error;
 
-		strbuf_addf(&sb, "%u:%s", type, name);
+		if (strbuf_addf(&sb, "%u:%s", type, name) < 0)
+			goto error;
 		/* include a NULL character at the end */
-		strbuf_add(&sb, "", 1);
+		if (strbuf_add(&sb, "", 1) < 0)
+			goto error;
 
 		if (!strcmp(name, "msr"))
 			ph->env.msr_pmu_type = type;
#6 lore raw

RFC PATCH 6/8 perf pmu: Make pmu_formats_string to check return value of strbuf

In reply to Masami Hiramatsu

Make pmu_formats_string() to check return value of strbuf APIs so that it can detect errors in it.

---
 tools/perf/util/pmu.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
tools/perf/util/pmu.c +5 -5
index bf34468..ddb0261 100644
@@ -643,20 +643,20 @@ static int pmu_resolve_param_term(struct parse_events_term *term,
 static char *pmu_formats_string(struct list_head *formats)
 {
 	struct perf_pmu_format *format;
-	char *str;
-	struct strbuf buf;
+	char *str = NULL;
+	struct strbuf buf = STRBUF_INIT;
 	unsigned i = 0;
 
 	if (!formats)
 		return NULL;
 
-	strbuf_init(&buf, 0);
 	/* sysfs exported terms */
 	list_for_each_entry(format, formats, list)
-		strbuf_addf(&buf, i++ ? ",%s" : "%s",
-			    format->name);
+		if (strbuf_addf(&buf, i++ ? ",%s" : "%s", format->name) < 0)
+			goto error;
 
 	str = strbuf_detach(&buf, NULL);
+error:
 	strbuf_release(&buf);
 
 	return str;
#7 lore raw

RFC PATCH 7/8 perf help: Do not use ALLOC_GROW in add_cmd_list

In reply to Masami Hiramatsu

Replace ALLOC_GROW with normal realloc code in add_cmd_list() so that it can handle errors directly.

---
 tools/perf/util/help-unknown-cmd.c |   30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)
tools/perf/util/help-unknown-cmd.c +22 -8
index 43a98a4..d62ccae 100644
@@ -27,16 +27,27 @@ static int levenshtein_compare(const void *p1, const void *p2)
 	return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 }
 
-static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
+static int add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 {
-	unsigned int i;
-
-	ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
-
+	unsigned int i, nr = cmds->cnt + old->cnt;
+	void *tmp;
+
+	if (nr > cmds->alloc) {
+		/* Choose bigger one to alloc */
+		if (alloc_nr(cmds->alloc) < nr)
+			cmds->alloc = nr;
+		else
+			cmds->alloc = alloc_nr(cmds->alloc);
+		tmp = realloc(cmds->names, cmds->alloc * sizeof(*cmds->names));
+		if (!tmp)
+			return -1;
+		cmds->names = tmp;
+	}
 	for (i = 0; i < old->cnt; i++)
 		cmds->names[cmds->cnt++] = old->names[i];
 	zfree(&old->names);
 	old->cnt = 0;
+	return 0;
 }
 
 const char *help_unknown_cmd(const char *cmd)
@@ -52,8 +63,11 @@ const char *help_unknown_cmd(const char *cmd)
 
 	load_command_list("perf-", &main_cmds, &other_cmds);
 
-	add_cmd_list(&main_cmds, &aliases);
-	add_cmd_list(&main_cmds, &other_cmds);
+	if (add_cmd_list(&main_cmds, &aliases) < 0 ||
+	    add_cmd_list(&main_cmds, &other_cmds) < 0) {
+		fprintf(stderr, "ERROR: Failed to allocate command list for unknown command.\n");
+		goto end;
+	}
 	qsort(main_cmds.names, main_cmds.cnt,
 	      sizeof(main_cmds.names), cmdname_compare);
 	uniq(&main_cmds);
@@ -99,6 +113,6 @@ const char *help_unknown_cmd(const char *cmd)
 		for (i = 0; i < n; i++)
 			fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 	}
-
+end:
 	exit(1);
 }
#8 lore raw

RFC PATCH 8/8 perf tools: Remove xrealloc and ALLOC_GROW

In reply to Masami Hiramatsu

Remove unused xrealloc() and ALLOC_GROW() from libperf.

---
 tools/perf/util/Build     |    1 -
 tools/perf/util/cache.h   |   19 -------------------
 tools/perf/util/util.h    |    6 ------
 tools/perf/util/wrapper.c |   29 -----------------------------
 4 files changed, 55 deletions(-)
 delete mode 100644 tools/perf/util/wrapper.c
tools/perf/util/Build +0 -1
index 90229a8..b7768ea 100644
@@ -27,7 +27,6 @@ libperf-y += strlist.o
 libperf-y += strfilter.o
 libperf-y += top.o
 libperf-y += usage.o
-libperf-y += wrapper.o
 libperf-y += dso.o
 libperf-y += symbol.o
 libperf-y += symbol_fprintf.o
tools/perf/util/cache.h +0 -19
index 1f5a93c..0d814bb 100644
@@ -40,25 +40,6 @@ int split_cmdline(char *cmdline, const char ***argv);
 
 #define alloc_nr(x) (((x)+16)*3/2)
 
-/*
- * Realloc the buffer pointed at by variable 'x' so that it can hold
- * at least 'nr' entries; the number of entries currently allocated
- * is 'alloc', using the standard growing factor alloc_nr() macro.
- *
- * DO NOT USE any expression with side-effect for 'x' or 'alloc'.
- */
-#define ALLOC_GROW(x, nr, alloc) \
-	do { \
-		if ((nr) > alloc) { \
-			if (alloc_nr(alloc) < (nr)) \
-				alloc = (nr); \
-			else \
-				alloc = alloc_nr(alloc); \
-			x = xrealloc((x), alloc * sizeof(*(x))); \
-		} \
-	} while(0)
-
-
 static inline int is_absolute_path(const char *path)
 {
 	return path[0] == '/';
tools/perf/util/util.h +0 -6
index 88f607a..7651633 100644
@@ -160,12 +160,6 @@ static inline char *gitstrchrnul(const char *s, int c)
 }
 #endif
 
-/*
- * Wrappers:
- */
-void *xrealloc(void *ptr, size_t size) __attribute__((weak));
-
-
 static inline void *zalloc(size_t size)
 {
 	return calloc(1, size);
tools/perf/util/wrapper.c deleted +0 -29
deleted file mode 100644
index 5f1a07c..0000000
@@ -1,29 +0,0 @@
-/*
- * Various trivial helper wrappers around standard functions
- */
-#include "cache.h"
-
-/*
- * There's no pack memory to release - but stay close to the Git
- * version so wrap this away:
- */
-static inline void release_pack_memory(size_t size __maybe_unused,
-				       int flag __maybe_unused)
-{
-}
-
-void *xrealloc(void *ptr, size_t size)
-{
-	void *ret = realloc(ptr, size);
-	if (!ret && !size)
-		ret = realloc(ptr, 1);
-	if (!ret) {
-		release_pack_memory(size, -1);
-		ret = realloc(ptr, size);
-		if (!ret && !size)
-			ret = realloc(ptr, 1);
-		if (!ret)
-			die("Out of memory, realloc failed");
-	}
-	return ret;
-}
#9 lore raw
In reply to Masami Hiramatsu

Em Fri, Apr 29, 2016 at 11:46:32PM +0900, Masami Hiramatsu escreveu:

Quoted 20 lines

Hi Arnaldo,

This patch series does refactoring strbuf and xrealloc related code to remove xrealloc since it can call die() to exit immediately when it hits any error. Instead of that, it should return error code to the caller so that the caller can handle its error.

Thus, at first, this changes the strbuf APIs to return error code instead of die() immediately. And then changing API callers according to the following rules.
- Check the return value of strbuf APIs and handle errors and,
- If the caller returns an error code (errno), it returns the return value of strbuf APIs.
- If the caller just return -1 or NULl in error case, it also returns -1 or NULL in case of strbuf error.
- If the caller can call die() directly, it also call die() in case of strbuf error.
- Error checking patches are splitted for each subcommand, since it will help review.

Quoted 6 lines

This also removes xrealloc and ALLOC_GROW from libperf, so that no one use it anymore.

This series actually depends on the series of SDT support patches which I've sent an hour ago. It is also able to change this not to depend on it easily. Please ask me if you'd like so.

Please do so, as this one looks easier to review, so can go in faster.

- Arnaldo

Quoted 36 lines

Thank you,

---

Masami Hiramatsu (8):
perf: Rewrite strbuf not to die
perf probe: Check the return value of strbuf APIs
perf help: Make check_emacsclient_version to check strbuf APIs
perf: Make alias handler to check return value of strbuf perf header: Make topology checkers to check return value of strbuf perf pmu: Make pmu_formats_string to check return value of strbuf perf help: Do not use ALLOC_GROW in add_cmd_list
perf tools: Remove xrealloc and ALLOC_GROW

 tools/perf/builtin-help.c          |   18 ++--
 tools/perf/perf.c                  |    8 +-
 tools/perf/util/Build              |    1 
 tools/perf/util/cache.h            |   19 ----
 tools/perf/util/dwarf-aux.c        |   50 +++++------
 tools/perf/util/header.c           |   31 ++++---
 tools/perf/util/help-unknown-cmd.c |   30 +++++-
 tools/perf/util/pmu.c              |   10 +-
 tools/perf/util/probe-event.c      |  167 +++++++++++++++++++++---------------
 tools/perf/util/probe-finder.c     |   30 ++++--
 tools/perf/util/quote.c            |   36 ++++----
 tools/perf/util/quote.h            |    2 
 tools/perf/util/strbuf.c           |   93 ++++++++++++++------
 tools/perf/util/strbuf.h           |   25 +++--
 tools/perf/util/util.h             |    6 -
 tools/perf/util/wrapper.c          |   29 ------
 16 files changed, 302 insertions(+), 253 deletions(-)
 delete mode 100644 tools/perf/util/wrapper.c

--
Masami Hiramatsu

#10 lore raw
Quoted 21 lines · On Fri, 29 Apr 2016 11:54:54 -0300 Arnaldo Carvalho de Melo <[email protected]>…

Em Fri, Apr 29, 2016 at 11:46:32PM +0900, Masami Hiramatsu escreveu:

Quoted 20 lines

Hi Arnaldo,

This patch series does refactoring strbuf and xrealloc related code to remove xrealloc since it can call die() to exit immediately when it hits any error. Instead of that, it should return error code to the caller so that the caller can handle its error.

Thus, at first, this changes the strbuf APIs to return error code instead of die() immediately. And then changing API callers according to the following rules.
- Check the return value of strbuf APIs and handle errors and,
- If the caller returns an error code (errno), it returns the return value of strbuf APIs.
- If the caller just return -1 or NULl in error case, it also returns -1 or NULL in case of strbuf error.
- If the caller can call die() directly, it also call die() in case of strbuf error.
- Error checking patches are splitted for each subcommand, since it will help review.

Quoted 8 lines
Quoted 6 lines

This also removes xrealloc and ALLOC_GROW from libperf, so that no one use it anymore.

This series actually depends on the series of SDT support patches which I've sent an hour ago. It is also able to change this not to depend on it easily. Please ask me if you'd like so.

Please do so, as this one looks easier to review, so can go in faster.

OK, I sent it as v2 in order to avoid confusion.

Thank you!

Signature · 1 line
Masami Hiramatsu <[email protected]>