Commit b32ee9e5 authored by Kan Liang's avatar Kan Liang Committed by Arnaldo Carvalho de Melo

perf tools: Lock to protect namespaces and comm list

Add two locks to protect namespaces_list and comm_list.

The lock is only needed for multithreaded code, so using mutex wrappers
provided by perf tool.

Not all the comm_list/namespaces_list accessing are protected, e.g.
thread__exec_comm. Because the multithread code for perf top event
synthesizing does not touch them. They don't need a lock.
Signed-off-by: default avatarKan Liang <kan.liang@intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1506696477-146932-2-git-send-email-kan.liang@intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 22905582
...@@ -45,6 +45,8 @@ struct thread *thread__new(pid_t pid, pid_t tid) ...@@ -45,6 +45,8 @@ struct thread *thread__new(pid_t pid, pid_t tid)
thread->cpu = -1; thread->cpu = -1;
INIT_LIST_HEAD(&thread->namespaces_list); INIT_LIST_HEAD(&thread->namespaces_list);
INIT_LIST_HEAD(&thread->comm_list); INIT_LIST_HEAD(&thread->comm_list);
init_rwsem(&thread->namespaces_lock);
init_rwsem(&thread->comm_lock);
comm_str = malloc(32); comm_str = malloc(32);
if (!comm_str) if (!comm_str)
...@@ -83,18 +85,26 @@ void thread__delete(struct thread *thread) ...@@ -83,18 +85,26 @@ void thread__delete(struct thread *thread)
map_groups__put(thread->mg); map_groups__put(thread->mg);
thread->mg = NULL; thread->mg = NULL;
} }
down_write(&thread->namespaces_lock);
list_for_each_entry_safe(namespaces, tmp_namespaces, list_for_each_entry_safe(namespaces, tmp_namespaces,
&thread->namespaces_list, list) { &thread->namespaces_list, list) {
list_del(&namespaces->list); list_del(&namespaces->list);
namespaces__free(namespaces); namespaces__free(namespaces);
} }
up_write(&thread->namespaces_lock);
down_write(&thread->comm_lock);
list_for_each_entry_safe(comm, tmp_comm, &thread->comm_list, list) { list_for_each_entry_safe(comm, tmp_comm, &thread->comm_list, list) {
list_del(&comm->list); list_del(&comm->list);
comm__free(comm); comm__free(comm);
} }
up_write(&thread->comm_lock);
unwind__finish_access(thread); unwind__finish_access(thread);
nsinfo__zput(thread->nsinfo); nsinfo__zput(thread->nsinfo);
exit_rwsem(&thread->namespaces_lock);
exit_rwsem(&thread->comm_lock);
free(thread); free(thread);
} }
...@@ -125,7 +135,7 @@ struct namespaces *thread__namespaces(const struct thread *thread) ...@@ -125,7 +135,7 @@ struct namespaces *thread__namespaces(const struct thread *thread)
return list_first_entry(&thread->namespaces_list, struct namespaces, list); return list_first_entry(&thread->namespaces_list, struct namespaces, list);
} }
int thread__set_namespaces(struct thread *thread, u64 timestamp, static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
struct namespaces_event *event) struct namespaces_event *event)
{ {
struct namespaces *new, *curr = thread__namespaces(thread); struct namespaces *new, *curr = thread__namespaces(thread);
...@@ -149,6 +159,17 @@ int thread__set_namespaces(struct thread *thread, u64 timestamp, ...@@ -149,6 +159,17 @@ int thread__set_namespaces(struct thread *thread, u64 timestamp,
return 0; return 0;
} }
int thread__set_namespaces(struct thread *thread, u64 timestamp,
struct namespaces_event *event)
{
int ret;
down_write(&thread->namespaces_lock);
ret = __thread__set_namespaces(thread, timestamp, event);
up_write(&thread->namespaces_lock);
return ret;
}
struct comm *thread__comm(const struct thread *thread) struct comm *thread__comm(const struct thread *thread)
{ {
if (list_empty(&thread->comm_list)) if (list_empty(&thread->comm_list))
...@@ -170,8 +191,8 @@ struct comm *thread__exec_comm(const struct thread *thread) ...@@ -170,8 +191,8 @@ struct comm *thread__exec_comm(const struct thread *thread)
return last; return last;
} }
int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp, static int ____thread__set_comm(struct thread *thread, const char *str,
bool exec) u64 timestamp, bool exec)
{ {
struct comm *new, *curr = thread__comm(thread); struct comm *new, *curr = thread__comm(thread);
...@@ -195,6 +216,17 @@ int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp, ...@@ -195,6 +216,17 @@ int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
return 0; return 0;
} }
int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
bool exec)
{
int ret;
down_write(&thread->comm_lock);
ret = ____thread__set_comm(thread, str, timestamp, exec);
up_write(&thread->comm_lock);
return ret;
}
int thread__set_comm_from_proc(struct thread *thread) int thread__set_comm_from_proc(struct thread *thread)
{ {
char path[64]; char path[64];
...@@ -212,7 +244,7 @@ int thread__set_comm_from_proc(struct thread *thread) ...@@ -212,7 +244,7 @@ int thread__set_comm_from_proc(struct thread *thread)
return err; return err;
} }
const char *thread__comm_str(const struct thread *thread) static const char *__thread__comm_str(const struct thread *thread)
{ {
const struct comm *comm = thread__comm(thread); const struct comm *comm = thread__comm(thread);
...@@ -222,6 +254,17 @@ const char *thread__comm_str(const struct thread *thread) ...@@ -222,6 +254,17 @@ const char *thread__comm_str(const struct thread *thread)
return comm__str(comm); return comm__str(comm);
} }
const char *thread__comm_str(const struct thread *thread)
{
const char *str;
down_read((struct rw_semaphore *)&thread->comm_lock);
str = __thread__comm_str(thread);
up_read((struct rw_semaphore *)&thread->comm_lock);
return str;
}
/* CHECKME: it should probably better return the max comm len from its comm list */ /* CHECKME: it should probably better return the max comm len from its comm list */
int thread__comm_len(struct thread *thread) int thread__comm_len(struct thread *thread)
{ {
......
...@@ -9,6 +9,7 @@ ...@@ -9,6 +9,7 @@
#include "symbol.h" #include "symbol.h"
#include <strlist.h> #include <strlist.h>
#include <intlist.h> #include <intlist.h>
#include "rwsem.h"
struct thread_stack; struct thread_stack;
struct unwind_libunwind_ops; struct unwind_libunwind_ops;
...@@ -29,7 +30,9 @@ struct thread { ...@@ -29,7 +30,9 @@ struct thread {
int comm_len; int comm_len;
bool dead; /* if set thread has exited */ bool dead; /* if set thread has exited */
struct list_head namespaces_list; struct list_head namespaces_list;
struct rw_semaphore namespaces_lock;
struct list_head comm_list; struct list_head comm_list;
struct rw_semaphore comm_lock;
u64 db_id; u64 db_id;
void *priv; void *priv;
......
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