+#include <asm/bug.h>
+#include <sys/time.h>
+#include <sys/resource.h>
#include "symbol.h"
#include "dso.h"
#include "machine.h"
return ret;
}
-static int open_dso(struct dso *dso, struct machine *machine)
+/*
+ * Global list of open DSOs and the counter.
+ */
+static LIST_HEAD(dso__data_open);
+static long dso__data_open_cnt;
+
+static void dso__list_add(struct dso *dso)
+{
+ list_add_tail(&dso->data.open_entry, &dso__data_open);
+ dso__data_open_cnt++;
+}
+
+static void dso__list_del(struct dso *dso)
+{
+ list_del(&dso->data.open_entry);
+ WARN_ONCE(dso__data_open_cnt <= 0,
+ "DSO data fd counter out of bounds.");
+ dso__data_open_cnt--;
+}
+
+static void close_first_dso(void);
+
+static int do_open(char *name)
+{
+ int fd;
+
+ do {
+ fd = open(name, O_RDONLY);
+ if (fd >= 0)
+ return fd;
+
+ pr_debug("dso open failed, mmap: %s\n", strerror(errno));
+ if (!dso__data_open_cnt || errno != EMFILE)
+ break;
+
+ close_first_dso();
+ } while (1);
+
+ return -1;
+}
+
+static int __open_dso(struct dso *dso, struct machine *machine)
{
int fd;
char *root_dir = (char *)"";
return -EINVAL;
}
- fd = open(name, O_RDONLY);
+ fd = do_open(name);
free(name);
return fd;
}
+static void check_data_close(void);
+
+/**
+ * dso_close - Open DSO data file
+ * @dso: dso object
+ *
+ * Open @dso's data file descriptor and updates
+ * list/count of open DSO objects.
+ */
+static int open_dso(struct dso *dso, struct machine *machine)
+{
+ int fd = __open_dso(dso, machine);
+
+ if (fd > 0) {
+ dso__list_add(dso);
+ /*
+ * Check if we crossed the allowed number
+ * of opened DSOs and close one if needed.
+ */
+ check_data_close();
+ }
+
+ return fd;
+}
+
+static void close_data_fd(struct dso *dso)
+{
+ if (dso->data.fd >= 0) {
+ close(dso->data.fd);
+ dso->data.fd = -1;
+ dso->data.file_size = 0;
+ dso__list_del(dso);
+ }
+}
+
+/**
+ * dso_close - Close DSO data file
+ * @dso: dso object
+ *
+ * Close @dso's data file descriptor and updates
+ * list/count of open DSO objects.
+ */
+static void close_dso(struct dso *dso)
+{
+ close_data_fd(dso);
+}
+
+static void close_first_dso(void)
+{
+ struct dso *dso;
+
+ dso = list_first_entry(&dso__data_open, struct dso, data.open_entry);
+ close_dso(dso);
+}
+
+static rlim_t get_fd_limit(void)
+{
+ struct rlimit l;
+ rlim_t limit = 0;
+
+ /* Allow half of the current open fd limit. */
+ if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
+ if (l.rlim_cur == RLIM_INFINITY)
+ limit = l.rlim_cur;
+ else
+ limit = l.rlim_cur / 2;
+ } else {
+ pr_err("failed to get fd limit\n");
+ limit = 1;
+ }
+
+ return limit;
+}
+
+static bool may_cache_fd(void)
+{
+ static rlim_t limit;
+
+ if (!limit)
+ limit = get_fd_limit();
+
+ if (limit == RLIM_INFINITY)
+ return true;
+
+ return limit > (rlim_t) dso__data_open_cnt;
+}
+
+/*
+ * Check and close LRU dso if we crossed allowed limit
+ * for opened dso file descriptors. The limit is half
+ * of the RLIMIT_NOFILE files opened.
+*/
+static void check_data_close(void)
+{
+ bool cache_fd = may_cache_fd();
+
+ if (!cache_fd)
+ close_first_dso();
+}
+
+/**
+ * dso__data_close - Close DSO data file
+ * @dso: dso object
+ *
+ * External interface to close @dso's data file descriptor.
+ */
+void dso__data_close(struct dso *dso)
+{
+ close_dso(dso);
+}
+
+/**
+ * dso__data_fd - Get dso's data file descriptor
+ * @dso: dso object
+ * @machine: machine object
+ *
+ * External interface to find dso's file, open it and
+ * returns file descriptor.
+ */
int dso__data_fd(struct dso *dso, struct machine *machine)
{
enum dso_binary_type binary_type_data[] = {
};
int i = 0;
- if (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND)
- return open_dso(dso, machine);
+ if (dso->data.fd >= 0)
+ return dso->data.fd;
+
+ if (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND) {
+ dso->data.fd = open_dso(dso, machine);
+ return dso->data.fd;
+ }
do {
int fd;
fd = open_dso(dso, machine);
if (fd >= 0)
- return fd;
+ return dso->data.fd = fd;
} while (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND);
}
static ssize_t
-dso_cache__read(struct dso *dso, struct machine *machine,
- u64 offset, u8 *data, ssize_t size)
+dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size)
{
struct dso_cache *cache;
ssize_t ret;
- int fd;
-
- fd = dso__data_fd(dso, machine);
- if (fd < 0)
- return -1;
do {
u64 cache_offset;
cache_offset = offset & DSO__DATA_CACHE_MASK;
ret = -EINVAL;
- if (-1 == lseek(fd, cache_offset, SEEK_SET))
+ if (-1 == lseek(dso->data.fd, cache_offset, SEEK_SET))
break;
- ret = read(fd, cache->data, DSO__DATA_CACHE_SIZE);
+ ret = read(dso->data.fd, cache->data, DSO__DATA_CACHE_SIZE);
if (ret <= 0)
break;
cache->offset = cache_offset;
cache->size = ret;
- dso_cache__insert(&dso->cache, cache);
+ dso_cache__insert(&dso->data.cache, cache);
ret = dso_cache__memcpy(cache, offset, data, size);
if (ret <= 0)
free(cache);
- close(fd);
return ret;
}
-static ssize_t dso_cache_read(struct dso *dso, struct machine *machine,
- u64 offset, u8 *data, ssize_t size)
+static ssize_t dso_cache_read(struct dso *dso, u64 offset,
+ u8 *data, ssize_t size)
{
struct dso_cache *cache;
- cache = dso_cache__find(&dso->cache, offset);
+ cache = dso_cache__find(&dso->data.cache, offset);
if (cache)
return dso_cache__memcpy(cache, offset, data, size);
else
- return dso_cache__read(dso, machine, offset, data, size);
+ return dso_cache__read(dso, offset, data, size);
}
-ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
- u64 offset, u8 *data, ssize_t size)
+/*
+ * Reads and caches dso data DSO__DATA_CACHE_SIZE size chunks
+ * 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)
{
ssize_t r = 0;
u8 *p = data;
do {
ssize_t ret;
- ret = dso_cache_read(dso, machine, offset, p, size);
+ ret = dso_cache_read(dso, offset, p, size);
if (ret < 0)
return ret;
return r;
}
+static int data_file_size(struct dso *dso)
+{
+ struct stat st;
+
+ if (!dso->data.file_size) {
+ if (fstat(dso->data.fd, &st)) {
+ pr_err("dso mmap failed, fstat: %s\n", strerror(errno));
+ return -1;
+ }
+ dso->data.file_size = st.st_size;
+ }
+
+ return 0;
+}
+
+static ssize_t data_read_offset(struct dso *dso, u64 offset,
+ u8 *data, ssize_t size)
+{
+ if (data_file_size(dso))
+ return -1;
+
+ /* Check the offset sanity. */
+ if (offset > dso->data.file_size)
+ return -1;
+
+ if (offset + size < offset)
+ return -1;
+
+ return cached_read(dso, offset, data, size);
+}
+
+/**
+ * dso__data_read_offset - Read data from dso file offset
+ * @dso: dso object
+ * @machine: machine object
+ * @offset: file offset
+ * @data: buffer to store data
+ * @size: size of the @data buffer
+ *
+ * External interface to read data from dso file offset. Open
+ * dso data file and use cached_read to get the data.
+ */
+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)
+ return -1;
+
+ return data_read_offset(dso, offset, data, size);
+}
+
+/**
+ * dso__data_read_addr - Read data from dso address
+ * @dso: dso object
+ * @machine: machine object
+ * @add: virtual memory address
+ * @data: buffer to store data
+ * @size: size of the @data buffer
+ *
+ * External interface to read data from dso address.
+ */
ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
struct machine *machine, u64 addr,
u8 *data, ssize_t size)
dso__set_short_name(dso, dso->name, false);
for (i = 0; i < MAP__NR_TYPES; ++i)
dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
- dso->cache = RB_ROOT;
+ dso->data.cache = RB_ROOT;
+ dso->data.fd = -1;
dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->binary_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->loaded = 0;
dso->kernel = DSO_TYPE_USER;
dso->needs_swap = DSO_SWAP__UNSET;
INIT_LIST_HEAD(&dso->node);
+ INIT_LIST_HEAD(&dso->data.open_entry);
}
return dso;
dso->long_name_allocated = false;
}
- dso_cache__free(&dso->cache);
+ dso__data_close(dso);
+ dso_cache__free(&dso->data.cache);
dso__free_a2l(dso);
zfree(&dso->symsrc_filename);
free(dso);
projects / cascardo / linux.git / blobdiff