perf/urgent fixes
Arnaldo Carvalho de Melo
maintainerHi Ingo,
Please consider pulling,
- Arnaldo
The following changes since commit d01de2389c0190f5959f0a1258a2e87d2fe4ca82:
Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent (2015-01-17 11:04:35 +0100)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-urgent-for-mingo
for you to fetch changes up to 25dd9171f51c482eb7c4dc8618766ae733756e2d:
perf probe: Fix probing kretprobes (2015-01-21 10:06:24 -0300)
----------------------------------------------------------------
perf/urgent fixes:
User visible:
- Fix probing at function return (Namhyumg Kim)
Developer stuff:
- Symbol processing changes necessary for fixing support for kretprobes in 'perf probe' (Namhyung Kim, Arnaldo Carvalho de Melo)
- Annotation memory leaks and instruction parsing fixes (Rabin Vincent)
- Fix perl build on ARM64 (Wang Nam)
----------------------------------------------------------------
Arnaldo Carvalho de Melo (3):
perf evlist: Remove extraneous 'was' on error message
perf symbols: Introduce method to iterate symbols ordered by name perf symbols: Introduce 'for' method to iterate over the symbols with a given name
Namhyung Kim (3):
perf symbols: Return the first entry with a given name in find_by_name method perf probe: Do not rely on map__load() filter to find symbols perf probe: Fix probing kretprobes
Rabin Vincent (2):
perf annotate: Handle ins parsing failures perf annotate: Fix memory leaks in LOCK handling
Wang Nan (1):
perf scripting perl: Force to use stdbool
tools/perf/scripts/perl/Perf-Trace-Util/Context.c | 5 +++- tools/perf/util/annotate.c | 18 +++++++++--- tools/perf/util/evlist.c | 2 +- tools/perf/util/map.h | 16 +++++++++++ tools/perf/util/probe-event.c | 34 +++++++++++------------ tools/perf/util/symbol.c | 31 +++++++++++++++++++-- tools/perf/util/symbol.h | 1 + 7 files changed, 80 insertions(+), 27 deletions(-)
Arnaldo Carvalho de Melo
maintainerPATCH 1/9 perf evlist: Remove extraneous 'was' on error message
From: Arnaldo Carvalho de Melo <[email protected]>
[acme@mica ~]$ trace -p 3330
Error: Unable to find debugfs
Hint: Was your kernel was compiled with debugfs support?
^^^
^^^ Hint: Is the debugfs filesystem mounted?
Hint: Try 'sudo mount -t debugfs nodev /sys/kernel/debug'
Fix it.
--- tools/perf/util/evlist.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
tools/perf/util/evlist.c +1 -1
@@ -1445,7 +1445,7 @@ int perf_evlist__strerror_tp(struct perf_evlist *evlist __maybe_unused,case ENOENT :scnprintf (buf, size,"%s" ,"Error:\tUnable to find debugfs\n" -"Hint:\tWas your kernel was compiled with debugfs support?\n" +"Hint:\tWas your kernel compiled with debugfs support?\n" "Hint:\tIs the debugfs filesystem mounted?\n" "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'" );break ;
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 2/9 perf scripting perl: Force to use stdbool
In reply to Arnaldo Carvalho de MeloFrom: Wang Nan <[email protected]>
When building perf for arm64 I hit a warning (and be treated as an error) like below:
aarch64-oe-linux-gcc -o .../scripts/perl/Perf-Trace-Util/Context.o -c -Wbad-function-cast \
... scripts/perl/Perf-Trace-Util/Context.c
In file included from .../usr/lib64/perl/5.14.3/CORE/perl.h:2464:0,
from Context.xs:23:
/.../usr/lib64/perl/5.14.3/CORE/handy.h:108:0: error: "bool" redefined [-Werror]
# define bool char
^
In file included from /.../usr/src/kernel/tools/include/linux/types.h:4:0,
from /.../usr/src/kernel/arch/arm64/include/uapi/asm/sigcontext.h:19,
from /.../usr/include/bits/sigcontext.h:27,
from /.../usr/include/signal.h:340,
from /.../usr/include/sys/param.h:28,
from /.../usr/lib64/perl/5.14.3/CORE/perl.h:678,
from Context.xs:23:
/.../usr/lib/aarch64-oe-linux/gcc/aarch64-oe-linux/4.9.2/include/stdbool.h:33:0: note: this is the location of the previous definition
#define bool _BoolLooks like the failure is caused by arm64 uapi/asm/sigcontext.h, which includes linux/types.h while other archs not.
Current perl consider this problem:
http://perl5.git.perl.org/perl.git/commit/bd31be4baa3ee68abdb92c0db3200efe0fad903b
However there are users which use old version of perl.
This patch includes stdbool.h before Context.xs and define HAS_BOOL to prevent perl'e headers define its own 'bool'. Code is learn from perl's git tree.
--- tools/perf/scripts/perl/Perf-Trace-Util/Context.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
tools/perf/scripts/perl/Perf-Trace-Util/Context.c +4 -1
@@ -5,7 +5,10 @@* ANY CHANGES MADE HERE WILL BE LOST! * */ - +#include <stdbool.h> +#ifndef HAS_BOOL +# define HAS_BOOL 1 +#endif #line 1 "Context.xs"/* * Context.xs. XS interfaces for perf script.
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 3/9 perf annotate: Handle ins parsing failures
In reply to Arnaldo Carvalho de MeloFrom: Rabin Vincent <[email protected]>
Don't use the ins's ->sncprintf() if the parsing failed.
For example, this fixes the display of "imul %edx". Without this patch:
| imul (null),(null)
After this patch:
| imul %edx
--- tools/perf/util/annotate.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
tools/perf/util/annotate.c +5 -4
@@ -183,8 +183,9 @@ static int lock__parse(struct ins_operands *ops)if (!ops->locked.ins->ops)return 0 ; -if (ops->locked.ins->ops->parse) - ops->locked.ins->ops->parse (ops->locked.ops); +if (ops->locked.ins->ops->parse && + ops->locked.ins->ops->parse (ops->locked.ops) <0 ) + goto out_free_ops;return 0 ;
@@ -531,8 +532,8 @@ static void disasm_line__init_ins(struct disasm_line *dl)if (!dl->ins->ops)return ; -if (dl->ins->ops->parse) - dl->ins->ops->parse (&dl->ops); +if (dl->ins->ops->parse && dl->ins->ops->parse (&dl->ops) <0 ) + dl->ins =NULL ; }static int disasm_line__parse (char *line,char **namep,char **rawp)
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 4/9 perf annotate: Fix memory leaks in LOCK handling
In reply to Arnaldo Carvalho de MeloFrom: Rabin Vincent <[email protected]>
The lock prefix handling fails to free the strdup()'d name as well as the fields allocated by the instruction parsing.
--- tools/perf/util/annotate.c | 9 +++++++++ 1 file changed, 9 insertions(+)
tools/perf/util/annotate.c +9 -0
@@ -177,6 +177,8 @@ static int lock__parse(struct ins_operands *ops) goto out_free_ops; ops->locked.ins =ins__find (name); +free (name); +if (ops->locked.ins ==NULL ) goto out_free_ops;
@@ -209,6 +211,13 @@ static int lock__scnprintf(struct ins *ins, char *bf, size_t size,static void lock__delete (struct ins_operands *ops) { +struct ins *ins = ops->locked.ins; + +if (ins && ins->ops->free) + ins->ops->free (ops->locked.ops); +else +ins__delete (ops->locked.ops); +zfree (&ops->locked.ops);zfree (&ops->target.raw);zfree (&ops->target.name);
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 5/9 perf symbols: Return the first entry with a given name in find_by_name method
In reply to Arnaldo Carvalho de MeloFrom: Namhyung Kim <[email protected]>
When a dso contains multiple symbols which have same name, current dso__find_symbol_by_name() only finds an one of them and there's no way to get the all symbols without going through the rbtree.
So make symbols__find_by_name() return the first entry with the given name and the next patch in this series will provide a way to iterate from there, by the name ordered rb_tree, till a suitable symbol is found.
--- tools/perf/util/symbol.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-)
tools/perf/util/symbol.c +17 -3
@@ -396,6 +396,7 @@ static struct symbol *symbols__find_by_name(struct rb_root *symbols, const char *name) {struct rb_node *n; +struct symbol_name_rb_node *s;if (symbols ==NULL )return NULL ;
@@ -403,7 +404,6 @@ static struct symbol *symbols__find_by_name(struct rb_root *symbols, n = symbols->rb_node;while (n) { -struct symbol_name_rb_node *s;int cmp; s = rb_entry(n, struct symbol_name_rb_node, rb_node);
@@ -414,10 +414,24 @@ static struct symbol *symbols__find_by_name(struct rb_root *symbols,else if (cmp >0 ) n = n->rb_right;else -return &s->sym; +break ; } -return NULL ; +if (n ==NULL ) +return NULL ; + +/* return first symbol that has same name (if any) */ +for (n =rb_prev (n); n; n =rb_prev (n)) { +struct symbol_name_rb_node *tmp; + + tmp = rb_entry(n, struct symbol_name_rb_node, rb_node); +if (strcmp (tmp->sym.name, s->sym.name)) +break ; + + s = tmp; + } + +return &s->sym; } struct symbol *dso__find_symbol(struct dso *dso,
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 6/9 perf symbols: Introduce method to iterate symbols ordered by name
In reply to Arnaldo Carvalho de MeloFrom: Arnaldo Carvalho de Melo <[email protected]>
Given a symbol, go to the next entry in a rbtree sorted by symbol name.
--- tools/perf/util/symbol.c | 11 +++++++++++ tools/perf/util/symbol.h | 1 + 2 files changed, 12 insertions(+)
tools/perf/util/symbol.c +11 -0
@@ -450,6 +450,17 @@ struct symbol *dso__next_symbol(struct symbol *sym)return symbols__next (sym); } +struct symbol *symbol__next_by_name (struct symbol *sym) +{ + struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym); +struct rb_node *n =rb_next (&s->rb_node); + + return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL; +} + +/* +* Teturns first symbol that matched with @name. +*/ struct symbol *dso__find_symbol_by_name (struct dso *dso,enum map_type type,const char *name) {
tools/perf/util/symbol.h +1 -0
@@ -231,6 +231,7 @@ struct symbol *dso__find_symbol(struct dso *dso, enum map_type type, u64 addr);struct symbol *dso__find_symbol_by_name (struct dso *dso,enum map_type type,const char *name); +struct symbol *symbol__next_by_name (struct symbol *sym);struct symbol *dso__first_symbol (struct dso *dso,enum map_type type);struct symbol *dso__next_symbol (struct symbol *sym);
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 7/9 perf probe: Do not rely on map__load() filter to find symbols
In reply to Arnaldo Carvalho de MeloFrom: Namhyung Kim <[email protected]>
The find_probe_trace_events_from_map() searches matching symbol from a map (so from a backing dso). For uprobes, it'll create a new map (and dso) and loads it using a filter. It's a little bit inefficient in that it'll read out the symbol table everytime but works well anyway.
For kprobes however, it'll reuse existing kernel map which might be loaded before. In this case map__load() just returns with no result. It makes kprobes always failed to find symbol even if it exists in the map (dso).
To fix it, use map__find_symbol_by_name() instead. It'll load a map with full symbols and sorts them by name. It needs to search sibing nodes since there can be multiple (local) symbols with same name.
--- tools/perf/util/probe-event.c | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-)
tools/perf/util/probe-event.c +22 -16
@@ -2193,18 +2193,20 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,return ret; } -static char *looking_function_name; -static int num_matched_functions; - -static int probe_function_filter (struct map *map__maybe_unused , -struct symbol *sym) +static int find_probe_functions (struct map *map,char *name) { -if ((sym->binding ==STB_GLOBAL || sym->binding ==STB_LOCAL ) && -strcmp (looking_function_name, sym->name) ==0 ) { - num_matched_functions++; -return 0 ; +int found =0 ; +struct symbol *sym =map__find_symbol_by_name (map, name,NULL ); + +while (sym !=NULL ) { +if (sym->binding ==STB_GLOBAL || sym->binding ==STB_LOCAL ) + found++; + sym =symbol__next_by_name (sym); +if (sym ==NULL ||strcmp (sym->name, name)) +break ; } -return 1 ; + +return found; }#define strdup_or_goto (str, label) \
@@ -2222,10 +2224,10 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,struct kmap *kmap =NULL ;struct ref_reloc_sym *reloc_sym =NULL ;struct symbol *sym; -struct rb_node *nd;struct probe_trace_event *tev;struct perf_probe_point *pp = &pev->point;struct probe_trace_point *tp; +int num_matched_functions;int ret, i;/* Init maps of given executable or kernel */
@@ -2242,10 +2244,8 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,* Load matched symbols: Since the different local symbols may have * same name but different addresses, this lists all the symbols. */ - num_matched_functions =0 ; - looking_function_name = pp->function; - ret =map__load (map, probe_function_filter); -if (ret || num_matched_functions ==0 ) { + num_matched_functions =find_probe_functions (map, pp->function); +if (num_matched_functions ==0 ) {pr_err ("Failed to find symbol %s in %s\n" , pp->function, target ? :"kernel" ); ret = -ENOENT ;
@@ -2275,7 +2275,9 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, } ret =0 ; -map__for_each_symbol (map, sym, nd) { + sym =map__find_symbol_by_name (map, pp->function,NULL ); + +while (sym !=NULL ) { tev = (*tevs) + ret; tp = &tev->point;if (ret == num_matched_functions) {
@@ -2323,6 +2325,10 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,strdup_or_goto (pev->args[i].type, nomem_out); } + + sym =symbol__next_by_name (sym); +if (sym ==NULL ||strcmp (sym->name, pp->function)) +break ; } out:
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 8/9 perf symbols: Introduce 'for' method to iterate over the symbols with a given name
In reply to Arnaldo Carvalho de MeloFrom: Arnaldo Carvalho de Melo <[email protected]>
Removing boilerplate from two places, where one would have to find the first entry, then iterate using symbol__next_by_name + strcmp to see if the next member had the same name.
--- tools/perf/util/map.h | 16 ++++++++++++++++ tools/perf/util/probe-event.c | 14 +++----------- 2 files changed, 19 insertions(+), 11 deletions(-)
tools/perf/util/map.h +16 -0
@@ -116,6 +116,22 @@ struct thread;#define map__for_each_symbol (map, pos, n) \ dso__for_each_symbol(map->dso, pos, n, map->type) +/* map__for_each_symbol_with_name - iterate over the symbols in the given map +* that have the given name +* +* @map: the 'struct map *' in which symbols itereated +* @sym_name: the symbol name +* @pos: the 'struct symbol *' to use as a loop cursor +* @filter: to use when loading the DSO +*/ +#define __map__for_each_symbol_by_name (map, sym_name, pos, filter) \ + for (pos = map__find_symbol_by_name(map, sym_name, filter); \ + pos && strcmp(pos->name, sym_name) == 0; \ + pos = symbol__next_by_name(pos)) + +#define map__for_each_symbol_by_name (map, sym_name, pos) \ + __map__for_each_symbol_by_name(map, sym_name, (pos), NULL) +typedef int (*symbol_filter_t )(struct map *map,struct symbol *sym); void map__init(struct map *map, enum map_type type,
tools/perf/util/probe-event.c +3 -11
@@ -2196,14 +2196,11 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,static int find_probe_functions (struct map *map,char *name) {int found =0 ; -struct symbol *sym =map__find_symbol_by_name (map, name,NULL ); +struct symbol *sym; -while (sym !=NULL ) { +map__for_each_symbol_by_name (map, name, sym) {if (sym->binding ==STB_GLOBAL || sym->binding ==STB_LOCAL ) found++; - sym =symbol__next_by_name (sym); -if (sym ==NULL ||strcmp (sym->name, name)) -break ; }return found;
@@ -2275,9 +2272,8 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, } ret =0 ; - sym =map__find_symbol_by_name (map, pp->function,NULL ); -while (sym !=NULL ) { +map__for_each_symbol_by_name (map, pp->function, sym) { tev = (*tevs) + ret; tp = &tev->point;if (ret == num_matched_functions) {
@@ -2325,10 +2321,6 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,strdup_or_goto (pev->args[i].type, nomem_out); } - - sym =symbol__next_by_name (sym); -if (sym ==NULL ||strcmp (sym->name, pp->function)) -break ; } out:
Signature · 1 line
1.9.3
Arnaldo Carvalho de Melo
maintainerPATCH 9/9 perf probe: Fix probing kretprobes
In reply to Arnaldo Carvalho de MeloFrom: Namhyung Kim <[email protected]>
The commit dfef99cd0b2c ("perf probe: Use ref_reloc_sym based address instead of the symbol name") converts kprobes to use ref_reloc_sym (i.e. _stext) and offset instead of using symbol's name directly. So on my system, adding do_fork ends up with like below:
$ sudo perf probe -v --add do_fork%return probe-definition(0): do_fork%return symbol:do_fork file:(null) line:0 offset:0 return:1 lazy:(null) 0 arguments Looking at the vmlinux_path (7 entries long) Using /lib/modules/3.17.6-1-ARCH/build/vmlinux for symbols Could not open debuginfo. Try to use symbols. Opening /sys/kernel/debug/tracing/kprobe_events write=1 Added new event: Writing event: r:probe/do_fork _stext+456136 Failed to write event: Invalid argument Error: Failed to add events. Reason: Operation not permitted (Code: -1)
As you can see, the do_fork was translated to _stext+456136. This was because to support (local) symbols that have same name. But the problem is that kretprobe requires to be inserted at function start point so it simply checks whether it's called with offset 0. And if not, it'll return with -EINVAL. You can see it with dmesg.
$ dmesg | tail -1
[125621.764103] Return probe must be used without offset.So we need to use the symbol name instead of ref_reloc_sym in case of return probes.
--- tools/perf/util/probe-event.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
tools/perf/util/probe-event.c +2 -2
@@ -446,7 +446,7 @@ static int post_process_probe_trace_events(struct probe_trace_event *tevs, }for (i =0 ; i < ntevs; i++) { -if (tevs[i].point.address) { +if (tevs[i].point.address && !tevs[i].point.retprobe) { tmp =strdup (reloc_sym->name);if (!tmp)return -ENOMEM ;
@@ -2254,7 +2254,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, goto out; } -if (!pev->uprobes) { +if (!pev->uprobes && !pp->retprobe) { kmap =map__kmap (map); reloc_sym = kmap->ref_reloc_sym;if (!reloc_sym) {
Signature · 1 line
1.9.3
Quoted 55 lines · Arnaldo Carvalho de Melo
Hi Ingo,
Please consider pulling,
- Arnaldo
The following changes since commit
d01de2389c0190f5959f0a1258a2e87d2fe4ca82:Merge tag 'perf-urgent-for-mingo' of
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linuxinto perf/urgent (2015-01-17 11:04:35 +0100)are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.gittags/perf-urgent-for-mingofor you to fetch changes up to
25dd9171f51c482eb7c4dc8618766ae733756e2d:perf probe: Fix probing kretprobes (2015-01-21 10:06:24 -0300)
----------------------------------------------------------------
perf/urgent fixes:User visible:
- Fix probing at function return (Namhyumg Kim)
Developer stuff:
- Symbol processing changes necessary for fixing support for kretprobes in 'perf probe' (Namhyung Kim, Arnaldo Carvalho de Melo)
- Annotation memory leaks and instruction parsing fixes (Rabin Vincent)
- Fix perl build on ARM64 (Wang Nam)
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>----------------------------------------------------------------
Arnaldo Carvalho de Melo (3):
perf evlist: Remove extraneous 'was' on error message
perf symbols: Introduce method to iterate symbols ordered by name perf symbols: Introduce 'for' method to iterate over the symbols with a given nameNamhyung Kim (3):
perf symbols: Return the first entry with a given name infind_by_namemethod perf probe: Do not rely onmap__load()filter to find symbols perf probe: Fix probing kretprobesRabin Vincent (2):
perf annotate: Handle ins parsing failures perf annotate: Fix memory leaks in LOCK handlingWang Nan (1):
perf scripting perl: Force to use stdbool
Quoted 8 lines
tools/perf/scripts/perl/Perf-Trace-Util/Context.c | 5 +++- tools/perf/util/annotate.c | 18 +++++++++--- tools/perf/util/evlist.c | 2 +- tools/perf/util/map.h | 16 +++++++++++ tools/perf/util/probe-event.c | 34 +++++++++++------------ tools/perf/util/symbol.c | 31 +++++++++++++++++++-- tools/perf/util/symbol.h | 1 + 7 files changed, 80 insertions(+), 27 deletions(-)
Pulled, thanks a lot Arnaldo!
Ingo