perf tools: Protect dso cache fd with a mutex
When dso cache is accessed in multi-thread environment, it's possible to close other dso->data.fd during operation due to open file limit. Protect the file descriptors using a separate mutex. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1431909055-21442-28-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
parent
8e67b7258e
commit
33bdedcea2
|
@ -265,6 +265,7 @@ int __kmod_path__parse(struct kmod_path *m, const char *path,
|
|||
*/
|
||||
static LIST_HEAD(dso__data_open);
|
||||
static long dso__data_open_cnt;
|
||||
static pthread_mutex_t dso__data_open_lock = PTHREAD_MUTEX_INITIALIZER;
|
||||
|
||||
static void dso__list_add(struct dso *dso)
|
||||
{
|
||||
|
@ -434,7 +435,9 @@ static void check_data_close(void)
|
|||
*/
|
||||
void dso__data_close(struct dso *dso)
|
||||
{
|
||||
pthread_mutex_lock(&dso__data_open_lock);
|
||||
close_dso(dso);
|
||||
pthread_mutex_unlock(&dso__data_open_lock);
|
||||
}
|
||||
|
||||
/**
|
||||
|
@ -457,6 +460,8 @@ int dso__data_fd(struct dso *dso, struct machine *machine)
|
|||
if (dso->data.status == DSO_DATA_STATUS_ERROR)
|
||||
return -1;
|
||||
|
||||
pthread_mutex_lock(&dso__data_open_lock);
|
||||
|
||||
if (dso->data.fd >= 0)
|
||||
goto out;
|
||||
|
||||
|
@ -479,6 +484,7 @@ out:
|
|||
else
|
||||
dso->data.status = DSO_DATA_STATUS_ERROR;
|
||||
|
||||
pthread_mutex_unlock(&dso__data_open_lock);
|
||||
return dso->data.fd;
|
||||
}
|
||||
|
||||
|
@ -583,7 +589,8 @@ dso_cache__memcpy(struct dso_cache *cache, u64 offset,
|
|||
}
|
||||
|
||||
static ssize_t
|
||||
dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
||||
dso_cache__read(struct dso *dso, struct machine *machine,
|
||||
u64 offset, u8 *data, ssize_t size)
|
||||
{
|
||||
struct dso_cache *cache;
|
||||
struct dso_cache *old;
|
||||
|
@ -592,11 +599,24 @@ dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
|||
do {
|
||||
u64 cache_offset;
|
||||
|
||||
ret = -ENOMEM;
|
||||
|
||||
cache = zalloc(sizeof(*cache) + DSO__DATA_CACHE_SIZE);
|
||||
if (!cache)
|
||||
break;
|
||||
return -ENOMEM;
|
||||
|
||||
pthread_mutex_lock(&dso__data_open_lock);
|
||||
|
||||
/*
|
||||
* dso->data.fd might be closed if other thread opened another
|
||||
* file (dso) due to open file limit (RLIMIT_NOFILE).
|
||||
*/
|
||||
if (dso->data.fd < 0) {
|
||||
dso->data.fd = open_dso(dso, machine);
|
||||
if (dso->data.fd < 0) {
|
||||
ret = -errno;
|
||||
dso->data.status = DSO_DATA_STATUS_ERROR;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
cache_offset = offset & DSO__DATA_CACHE_MASK;
|
||||
|
||||
|
@ -606,6 +626,11 @@ dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
|||
|
||||
cache->offset = cache_offset;
|
||||
cache->size = ret;
|
||||
} while (0);
|
||||
|
||||
pthread_mutex_unlock(&dso__data_open_lock);
|
||||
|
||||
if (ret > 0) {
|
||||
old = dso_cache__insert(dso, cache);
|
||||
if (old) {
|
||||
/* we lose the race */
|
||||
|
@ -614,8 +639,7 @@ dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
|||
}
|
||||
|
||||
ret = dso_cache__memcpy(cache, offset, data, size);
|
||||
|
||||
} while (0);
|
||||
}
|
||||
|
||||
if (ret <= 0)
|
||||
free(cache);
|
||||
|
@ -623,8 +647,8 @@ dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static ssize_t dso_cache_read(struct dso *dso, u64 offset,
|
||||
u8 *data, ssize_t size)
|
||||
static ssize_t dso_cache_read(struct dso *dso, struct machine *machine,
|
||||
u64 offset, u8 *data, ssize_t size)
|
||||
{
|
||||
struct dso_cache *cache;
|
||||
|
||||
|
@ -632,7 +656,7 @@ static ssize_t dso_cache_read(struct dso *dso, u64 offset,
|
|||
if (cache)
|
||||
return dso_cache__memcpy(cache, offset, data, size);
|
||||
else
|
||||
return dso_cache__read(dso, offset, data, size);
|
||||
return dso_cache__read(dso, machine, offset, data, size);
|
||||
}
|
||||
|
||||
/*
|
||||
|
@ -640,7 +664,8 @@ static ssize_t dso_cache_read(struct dso *dso, u64 offset,
|
|||
* in the rb_tree. Any read to already cached data is served
|
||||
* by cached data.
|
||||
*/
|
||||
static ssize_t cached_read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
||||
static ssize_t cached_read(struct dso *dso, struct machine *machine,
|
||||
u64 offset, u8 *data, ssize_t size)
|
||||
{
|
||||
ssize_t r = 0;
|
||||
u8 *p = data;
|
||||
|
@ -648,7 +673,7 @@ static ssize_t cached_read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
|||
do {
|
||||
ssize_t ret;
|
||||
|
||||
ret = dso_cache_read(dso, offset, p, size);
|
||||
ret = dso_cache_read(dso, machine, offset, p, size);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
|
@ -668,21 +693,42 @@ static ssize_t cached_read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
|
|||
return r;
|
||||
}
|
||||
|
||||
static int data_file_size(struct dso *dso)
|
||||
static int data_file_size(struct dso *dso, struct machine *machine)
|
||||
{
|
||||
int ret = 0;
|
||||
struct stat st;
|
||||
char sbuf[STRERR_BUFSIZE];
|
||||
|
||||
if (!dso->data.file_size) {
|
||||
if (fstat(dso->data.fd, &st)) {
|
||||
pr_err("dso mmap failed, fstat: %s\n",
|
||||
strerror_r(errno, sbuf, sizeof(sbuf)));
|
||||
return -1;
|
||||
if (dso->data.file_size)
|
||||
return 0;
|
||||
|
||||
pthread_mutex_lock(&dso__data_open_lock);
|
||||
|
||||
/*
|
||||
* dso->data.fd might be closed if other thread opened another
|
||||
* file (dso) due to open file limit (RLIMIT_NOFILE).
|
||||
*/
|
||||
if (dso->data.fd < 0) {
|
||||
dso->data.fd = open_dso(dso, machine);
|
||||
if (dso->data.fd < 0) {
|
||||
ret = -errno;
|
||||
dso->data.status = DSO_DATA_STATUS_ERROR;
|
||||
goto out;
|
||||
}
|
||||
dso->data.file_size = st.st_size;
|
||||
}
|
||||
|
||||
return 0;
|
||||
if (fstat(dso->data.fd, &st) < 0) {
|
||||
ret = -errno;
|
||||
pr_err("dso cache fstat failed: %s\n",
|
||||
strerror_r(errno, sbuf, sizeof(sbuf)));
|
||||
dso->data.status = DSO_DATA_STATUS_ERROR;
|
||||
goto out;
|
||||
}
|
||||
dso->data.file_size = st.st_size;
|
||||
|
||||
out:
|
||||
pthread_mutex_unlock(&dso__data_open_lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
|
@ -700,17 +746,17 @@ off_t dso__data_size(struct dso *dso, struct machine *machine)
|
|||
if (fd < 0)
|
||||
return fd;
|
||||
|
||||
if (data_file_size(dso))
|
||||
if (data_file_size(dso, machine))
|
||||
return -1;
|
||||
|
||||
/* For now just estimate dso data size is close to file size */
|
||||
return dso->data.file_size;
|
||||
}
|
||||
|
||||
static ssize_t data_read_offset(struct dso *dso, u64 offset,
|
||||
u8 *data, ssize_t size)
|
||||
static ssize_t data_read_offset(struct dso *dso, struct machine *machine,
|
||||
u64 offset, u8 *data, ssize_t size)
|
||||
{
|
||||
if (data_file_size(dso))
|
||||
if (data_file_size(dso, machine))
|
||||
return -1;
|
||||
|
||||
/* Check the offset sanity. */
|
||||
|
@ -720,7 +766,7 @@ static ssize_t data_read_offset(struct dso *dso, u64 offset,
|
|||
if (offset + size < offset)
|
||||
return -1;
|
||||
|
||||
return cached_read(dso, offset, data, size);
|
||||
return cached_read(dso, machine, offset, data, size);
|
||||
}
|
||||
|
||||
/**
|
||||
|
@ -737,10 +783,10 @@ static ssize_t data_read_offset(struct dso *dso, u64 offset,
|
|||
ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
|
||||
u64 offset, u8 *data, ssize_t size)
|
||||
{
|
||||
if (dso__data_fd(dso, machine) < 0)
|
||||
if (dso->data.status == DSO_DATA_STATUS_ERROR)
|
||||
return -1;
|
||||
|
||||
return data_read_offset(dso, offset, data, size);
|
||||
return data_read_offset(dso, machine, offset, data, size);
|
||||
}
|
||||
|
||||
/**
|
||||
|
|
Loading…
Reference in New Issue