lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <20200522065330.34872-1-nick.gasson@arm.com>
Date:   Fri, 22 May 2020 14:53:30 +0800
From:   Nick Gasson <nick.gasson@....com>
To:     Arnaldo Carvalho de Melo <acme@...nel.org>,
        Jiri Olsa <jolsa@...hat.com>, Ian Rogers <irogers@...gle.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Stephane Eranian <eranian@...gle.com>
Cc:     Nick Gasson <nick.gasson@....com>, linux-kernel@...r.kernel.org
Subject: [PATCH] perf jvmti: remove redundant jitdump line table entries

For each PC/BCI pair in the JVMTI compiler inlining record table, the
jitdump plugin emits debug line table entries for every source line in
the method preceding that BCI. Instead only emit one source line per
PC/BCI pair. Reported by Ian Rogers. This reduces the .dump size for
SPECjbb from ~230MB to ~40MB.

Also fix an error in the DWARF line table state machine where addresses
are incorrectly offset by -0x40 (GEN_ELF_TEXT_OFFSET). This can be seen
with `objdump -S` on the ELF files after perf inject.

Signed-off-by: Nick Gasson <nick.gasson@....com>
---
 tools/perf/jvmti/libjvmti.c    | 73 +++++++++++++---------------------
 tools/perf/util/genelf_debug.c |  4 +-
 2 files changed, 30 insertions(+), 47 deletions(-)

diff --git a/tools/perf/jvmti/libjvmti.c b/tools/perf/jvmti/libjvmti.c
index a9a056d68416..398e4ba6498d 100644
--- a/tools/perf/jvmti/libjvmti.c
+++ b/tools/perf/jvmti/libjvmti.c
@@ -32,38 +32,41 @@ static void print_error(jvmtiEnv *jvmti, const char *msg, jvmtiError ret)
 
 #ifdef HAVE_JVMTI_CMLR
 static jvmtiError
-do_get_line_numbers(jvmtiEnv *jvmti, void *pc, jmethodID m, jint bci,
-		    jvmti_line_info_t *tab, jint *nr)
+do_get_line_number(jvmtiEnv *jvmti, void *pc, jmethodID m, jint bci,
+		   jvmti_line_info_t *tab)
 {
-	jint i, lines = 0;
-	jint nr_lines = 0;
+	jint i, nr_lines = 0;
 	jvmtiLineNumberEntry *loc_tab = NULL;
 	jvmtiError ret;
+	jint src_line = -1;
 
 	ret = (*jvmti)->GetLineNumberTable(jvmti, m, &nr_lines, &loc_tab);
 	if (ret == JVMTI_ERROR_ABSENT_INFORMATION || ret == JVMTI_ERROR_NATIVE_METHOD) {
 		/* No debug information for this method */
-		*nr = 0;
-		return JVMTI_ERROR_NONE;
+		return ret;
 	} else if (ret != JVMTI_ERROR_NONE) {
 		print_error(jvmti, "GetLineNumberTable", ret);
 		return ret;
 	}
 
-	for (i = 0; i < nr_lines; i++) {
-		if (loc_tab[i].start_location < bci) {
-			tab[lines].pc = (unsigned long)pc;
-			tab[lines].line_number = loc_tab[i].line_number;
-			tab[lines].discrim = 0; /* not yet used */
-			tab[lines].methodID = m;
-			lines++;
-		} else {
-			break;
-		}
+	for (i = 0; i < nr_lines && loc_tab[i].start_location <= bci; i++) {
+		src_line = i;
+	}
+
+	if (src_line != -1) {
+		tab->pc = (unsigned long)pc;
+		tab->line_number = loc_tab[src_line].line_number;
+		tab->discrim = 0; /* not yet used */
+		tab->methodID = m;
+
+		ret = JVMTI_ERROR_NONE;
+	} else {
+		ret = JVMTI_ERROR_ABSENT_INFORMATION;
 	}
+
 	(*jvmti)->Deallocate(jvmti, (unsigned char *)loc_tab);
-	*nr = lines;
-	return JVMTI_ERROR_NONE;
+
+	return ret;
 }
 
 static jvmtiError
@@ -71,9 +74,8 @@ get_line_numbers(jvmtiEnv *jvmti, const void *compile_info, jvmti_line_info_t **
 {
 	const jvmtiCompiledMethodLoadRecordHeader *hdr;
 	jvmtiCompiledMethodLoadInlineRecord *rec;
-	jvmtiLineNumberEntry *lne = NULL;
 	PCStackInfo *c;
-	jint nr, ret;
+	jint ret;
 	int nr_total = 0;
 	int i, lines_total = 0;
 
@@ -86,24 +88,7 @@ get_line_numbers(jvmtiEnv *jvmti, const void *compile_info, jvmti_line_info_t **
 	for (hdr = compile_info; hdr != NULL; hdr = hdr->next) {
 		if (hdr->kind == JVMTI_CMLR_INLINE_INFO) {
 			rec = (jvmtiCompiledMethodLoadInlineRecord *)hdr;
-			for (i = 0; i < rec->numpcs; i++) {
-				c = rec->pcinfo + i;
-				nr = 0;
-				/*
-				 * unfortunately, need a tab to get the number of lines!
-				 */
-				ret = (*jvmti)->GetLineNumberTable(jvmti, c->methods[0], &nr, &lne);
-				if (ret == JVMTI_ERROR_NONE) {
-					/* free what was allocated for nothing */
-					(*jvmti)->Deallocate(jvmti, (unsigned char *)lne);
-					nr_total += (int)nr;
-				} else if (ret == JVMTI_ERROR_ABSENT_INFORMATION
-					   || ret == JVMTI_ERROR_NATIVE_METHOD) {
-					/* No debug information for this method */
-				} else {
-					print_error(jvmti, "GetLineNumberTable", ret);
-				}
-			}
+			nr_total += rec->numpcs;
 		}
 	}
 
@@ -122,14 +107,12 @@ get_line_numbers(jvmtiEnv *jvmti, const void *compile_info, jvmti_line_info_t **
 			rec = (jvmtiCompiledMethodLoadInlineRecord *)hdr;
 			for (i = 0; i < rec->numpcs; i++) {
 				c = rec->pcinfo + i;
-				nr = 0;
-				ret = do_get_line_numbers(jvmti, c->pc,
-							  c->methods[0],
-							  c->bcis[0],
-							  *tab + lines_total,
-							  &nr);
+				ret = do_get_line_number(jvmti, c->pc,
+							 c->methods[0],
+							 c->bcis[0],
+							 *tab + lines_total);
 				if (ret == JVMTI_ERROR_NONE)
-					lines_total += nr;
+					lines_total++;
 			}
 		}
 	}
diff --git a/tools/perf/util/genelf_debug.c b/tools/perf/util/genelf_debug.c
index 30e9f618f6cd..dd40683bd4c0 100644
--- a/tools/perf/util/genelf_debug.c
+++ b/tools/perf/util/genelf_debug.c
@@ -342,7 +342,7 @@ static void emit_lineno_info(struct buffer_ext *be,
 	 */
 
 	/* start state of the state machine we take care of */
-	unsigned long last_vma = code_addr;
+	unsigned long last_vma = 0;
 	char const  *cur_filename = NULL;
 	unsigned long cur_file_idx = 0;
 	int last_line = 1;
@@ -473,7 +473,7 @@ jit_process_debug_info(uint64_t code_addr,
 		ent = debug_entry_next(ent);
 	}
 	add_compilation_unit(di, buffer_ext_size(dl));
-	add_debug_line(dl, debug, nr_debug_entries, 0);
+	add_debug_line(dl, debug, nr_debug_entries, GEN_ELF_TEXT_OFFSET);
 	add_debug_abbrev(da);
 	if (0) buffer_ext_dump(da, "abbrev");
 
-- 
2.26.2

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ