1 files changed, 133 insertions, 38 deletions

diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c
index c47aa34fdc0a..164eb45a0b36 100644
--- a/tools/perf/util/data.c
+++ b/tools/perf/util/data.c
@@ -3,6 +3,7 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/zalloc.h>
+#include <linux/err.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <errno.h>
@@ -16,11 +17,12 @@
 #include "util.h" // rm_rf_perf_data()
 #include "debug.h"
 #include "header.h"
+#include "rlimit.h"
 #include <internal/lib.h>
 
 static void close_dir(struct perf_data_file *files, int nr)
 {
-	while (--nr >= 1) {
+	while (--nr >= 0) {
 		close(files[nr].fd);
 		zfree(&files[nr].path);
 	}
@@ -34,8 +36,9 @@ void perf_data__close_dir(struct perf_data *data)
 
 int perf_data__create_dir(struct perf_data *data, int nr)
 {
+	enum rlimit_action set_rlimit = NO_CHANGE;
 	struct perf_data_file *files = NULL;
-	int i, ret = -1;
+	int i, ret;
 
 	if (WARN_ON(!data->is_dir))
 		return -EINVAL;
@@ -44,23 +47,37 @@ int perf_data__create_dir(struct perf_data *data, int nr)
 	if (!files)
 		return -ENOMEM;
 
-	data->dir.version = PERF_DIR_VERSION;
-	data->dir.files   = files;
-	data->dir.nr      = nr;
-
 	for (i = 0; i < nr; i++) {
 		struct perf_data_file *file = &files[i];
 
-		if (asprintf(&file->path, "%s/data.%d", data->path, i) < 0)
+		ret = asprintf(&file->path, "%s/data.%d", data->path, i);
+		if (ret < 0) {
+			ret = -ENOMEM;
 			goto out_err;
+		}
 
+retry_open:
 		ret = open(file->path, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);
-		if (ret < 0)
+		if (ret < 0) {
+			/*
+			 * If using parallel threads to collect data,
+			 * perf record needs at least 6 fds per CPU.
+			 * When we run out of them try to increase the limits.
+			 */
+			if (errno == EMFILE && rlimit__increase_nofile(&set_rlimit))
+				goto retry_open;
+
+			ret = -errno;
 			goto out_err;
+		}
+		set_rlimit = NO_CHANGE;
 
 		file->fd = ret;
 	}
 
+	data->dir.version = PERF_DIR_VERSION;
+	data->dir.files   = files;
+	data->dir.nr      = nr;
 	return 0;
 
 out_err:
@@ -127,6 +144,7 @@ int perf_data__open_dir(struct perf_data *data)
 		file->size = st.st_size;
 	}
 
+	closedir(dir);
 	if (!files)
 		return -EINVAL;
 
@@ -135,30 +153,11 @@ int perf_data__open_dir(struct perf_data *data)
 	return 0;
 
 out_err:
+	closedir(dir);
 	close_dir(files, nr);
 	return ret;
 }
 
-int perf_data__update_dir(struct perf_data *data)
-{
-	int i;
-
-	if (WARN_ON(!data->is_dir))
-		return -EINVAL;
-
-	for (i = 0; i < data->dir.nr; i++) {
-		struct perf_data_file *file = &data->dir.files[i];
-		struct stat st;
-
-		if (fstat(file->fd, &st))
-			return -1;
-
-		file->size = st.st_size;
-	}
-
-	return 0;
-}
-
 static bool check_pipe(struct perf_data *data)
 {
 	struct stat st;
@@ -174,8 +173,26 @@ static bool check_pipe(struct perf_data *data)
 			is_pipe = true;
 	}
 
-	if (is_pipe)
-		data->file.fd = fd;
+	if (is_pipe) {
+		if (data->use_stdio) {
+			const char *mode;
+
+			mode = perf_data__is_read(data) ? "r" : "w";
+			data->file.fptr = fdopen(fd, mode);
+
+			if (data->file.fptr == NULL) {
+				data->file.fd = fd;
+				data->use_stdio = false;
+			}
+
+		/*
+		 * When is_pipe and data->file.fd is given, use given fd
+		 * instead of STDIN_FILENO or STDOUT_FILENO
+		 */
+		} else if (data->file.fd <= 0) {
+			data->file.fd = fd;
+		}
+	}
 
 	return data->is_pipe = is_pipe;
 }
@@ -226,11 +243,12 @@ static bool is_dir(struct perf_data *data)
 
 static int open_file_read(struct perf_data *data)
 {
+	int flags = data->in_place_update ? O_RDWR : O_RDONLY;
 	struct stat st;
 	int fd;
 	char sbuf[STRERR_BUFSIZE];
 
-	fd = open(data->file.path, O_RDONLY);
+	fd = open(data->file.path, flags);
 	if (fd < 0) {
 		int err = errno;
 
@@ -334,6 +352,9 @@ int perf_data__open(struct perf_data *data)
 	if (check_pipe(data))
 		return 0;
 
+	/* currently it allows stdio for pipe only */
+	data->use_stdio = false;
+
 	if (!data->path)
 		data->path = "perf.data";
 
@@ -353,7 +374,21 @@ void perf_data__close(struct perf_data *data)
 		perf_data__close_dir(data);
 
 	zfree(&data->file.path);
-	close(data->file.fd);
+
+	if (data->use_stdio)
+		fclose(data->file.fptr);
+	else
+		close(data->file.fd);
+}
+
+ssize_t perf_data__read(struct perf_data *data, void *buf, size_t size)
+{
+	if (data->use_stdio) {
+		if (fread(buf, size, 1, data->file.fptr) == 1)
+			return size;
+		return feof(data->file.fptr) ? 0 : -1;
+	}
+	return readn(data->file.fd, buf, size);
 }
 
 ssize_t perf_data_file__write(struct perf_data_file *file,
@@ -363,20 +398,23 @@ ssize_t perf_data_file__write(struct perf_data_file *file,
 }
 
 ssize_t perf_data__write(struct perf_data *data,
-			      void *buf, size_t size)
+			 void *buf, size_t size)
 {
+	if (data->use_stdio) {
+		if (fwrite(buf, size, 1, data->file.fptr) == 1)
+			return size;
+		return -1;
+	}
 	return perf_data_file__write(&data->file, buf, size);
 }
 
 int perf_data__switch(struct perf_data *data,
-			   const char *postfix,
-			   size_t pos, bool at_exit,
-			   char **new_filepath)
+		      const char *postfix,
+		      size_t pos, bool at_exit,
+		      char **new_filepath)
 {
 	int ret;
 
-	if (check_pipe(data))
-		return -EINVAL;
 	if (perf_data__is_read(data))
 		return -EINVAL;
 
@@ -439,6 +477,25 @@ int perf_data__make_kcore_dir(struct perf_data *data, char *buf, size_t buf_sz)
 	return mkdir(buf, S_IRWXU);
 }
 
+bool has_kcore_dir(const char *path)
+{
+	struct dirent *d = ERR_PTR(-EINVAL);
+	const char *name = "kcore_dir";
+	DIR *dir = opendir(path);
+	size_t n = strlen(name);
+	bool result = false;
+
+	if (dir) {
+		while (d && !result) {
+			d = readdir(dir);
+			result = d ? strncmp(d->d_name, name, n) : false;
+		}
+		closedir(dir);
+	}
+
+	return result;
+}
+
 char *perf_data__kallsyms_name(struct perf_data *data)
 {
 	char *kallsyms_name;
@@ -457,3 +514,41 @@ char *perf_data__kallsyms_name(struct perf_data *data)
 
 	return kallsyms_name;
 }
+
+char *perf_data__guest_kallsyms_name(struct perf_data *data, pid_t machine_pid)
+{
+	char *kallsyms_name;
+	struct stat st;
+
+	if (!data->is_dir)
+		return NULL;
+
+	if (asprintf(&kallsyms_name, "%s/kcore_dir__%d/kallsyms", data->path, machine_pid) < 0)
+		return NULL;
+
+	if (stat(kallsyms_name, &st)) {
+		free(kallsyms_name);
+		return NULL;
+	}
+
+	return kallsyms_name;
+}
+
+bool is_perf_data(const char *path)
+{
+	bool ret = false;
+	FILE *file;
+	u64 magic;
+
+	file = fopen(path, "r");
+	if (!file)
+		return false;
+
+	if (fread(&magic, 1, 8, file) < 8)
+		goto out;
+
+	ret = is_perf_magic(magic);
+out:
+	fclose(file);
+	return ret;
+}