summaryrefslogtreecommitdiffstats
path: root/tools/objtool/builtin-check.c
diff options
context:
space:
mode:
authorJosh Poimboeuf <jpoimboe@redhat.com>2016-03-09 00:07:00 -0600
committerIngo Molnar <mingo@kernel.org>2016-03-09 10:48:10 +0100
commit042ba73fe7eb63872ee2d6ac86410052210c1f16 (patch)
tree6f3efe312fc1f2716f0f477a5860a3b6aed3e351 /tools/objtool/builtin-check.c
parent1698872b5c772aebc5c43ca445cc0a79f12b9fcc (diff)
downloadlinux-042ba73fe7eb63872ee2d6ac86410052210c1f16.tar.gz
linux-042ba73fe7eb63872ee2d6ac86410052210c1f16.tar.bz2
linux-042ba73fe7eb63872ee2d6ac86410052210c1f16.zip
objtool: Add several performance improvements
Use hash tables for instruction and rela lookups (and keep the linked lists around for sequential access). Also cache the section struct for the "__func_stack_frame_non_standard" section. With this change, "objtool check net/wireless/nl80211.o" goes from: real 0m1.168s user 0m1.163s sys 0m0.005s to: real 0m0.059s user 0m0.042s sys 0m0.017s for a 20x speedup. With the same object, it should be noted that the memory heap usage grew from 8MB to 62MB. Reducing the memory usage is on the TODO list. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/dd0d8e1449506cfa7701b4e7ba73577077c44253.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools/objtool/builtin-check.c')
-rw-r--r--tools/objtool/builtin-check.c18
1 files changed, 12 insertions, 6 deletions
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index cf1e48dbfa97..bfeee227aaab 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -34,6 +34,8 @@
#include "arch.h"
#include "warn.h"
+#include <linux/hashtable.h>
+
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
#define STATE_FP_SAVED 0x1
@@ -42,6 +44,7 @@
struct instruction {
struct list_head list;
+ struct hlist_node hash;
struct section *sec;
unsigned long offset;
unsigned int len, state;
@@ -61,7 +64,8 @@ struct alternative {
struct objtool_file {
struct elf *elf;
struct list_head insn_list;
- struct section *rodata;
+ DECLARE_HASHTABLE(insn_hash, 16);
+ struct section *rodata, *whitelist;
};
const char *objname;
@@ -72,7 +76,7 @@ static struct instruction *find_insn(struct objtool_file *file,
{
struct instruction *insn;
- list_for_each_entry(insn, &file->insn_list, list)
+ hash_for_each_possible(file->insn_hash, insn, hash, offset)
if (insn->sec == sec && insn->offset == offset)
return insn;
@@ -111,14 +115,12 @@ static struct instruction *next_insn_same_sec(struct objtool_file *file,
*/
static bool ignore_func(struct objtool_file *file, struct symbol *func)
{
- struct section *macro_sec;
struct rela *rela;
struct instruction *insn;
/* check for STACK_FRAME_NON_STANDARD */
- macro_sec = find_section_by_name(file->elf, "__func_stack_frame_non_standard");
- if (macro_sec && macro_sec->rela)
- list_for_each_entry(rela, &macro_sec->rela->rela_list, list)
+ if (file->whitelist && file->whitelist->rela)
+ list_for_each_entry(rela, &file->whitelist->rela->rela_list, list)
if (rela->sym->sec == func->sec &&
rela->addend == func->offset)
return true;
@@ -276,6 +278,7 @@ static int decode_instructions(struct objtool_file *file)
return -1;
}
+ hash_add(file->insn_hash, &insn->hash, insn->offset);
list_add_tail(&insn->list, &file->insn_list);
}
}
@@ -729,6 +732,7 @@ static int decode_sections(struct objtool_file *file)
{
int ret;
+ file->whitelist = find_section_by_name(file->elf, "__func_stack_frame_non_standard");
file->rodata = find_section_by_name(file->elf, ".rodata");
ret = decode_instructions(file);
@@ -1091,6 +1095,7 @@ static void cleanup(struct objtool_file *file)
free(alt);
}
list_del(&insn->list);
+ hash_del(&insn->hash);
free(insn);
}
elf_close(file->elf);
@@ -1125,6 +1130,7 @@ int cmd_check(int argc, const char **argv)
}
INIT_LIST_HEAD(&file.insn_list);
+ hash_init(file.insn_hash);
ret = decode_sections(&file);
if (ret < 0)