From 040f9915e99e604688c2880e0b1e5b59dbfefa54 Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Wed, 13 Apr 2016 08:21:05 +0000 Subject: [PATCH] perf data: Add perf_data_file__switch() helper perf_data_file__switch() closes current output file, renames it, then open a new one to continue recording. It will be used by 'perf record' to split output into multiple perf.data files. Signed-off-by: Wang Nan Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1460535673-159866-3-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/data.c | 41 +++++++++++++++++++++++++++++++++++++++++ tools/perf/util/data.h | 11 ++++++++++- 2 files changed, 51 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c index 1921942fc2e0..be83516155ee 100644 --- a/tools/perf/util/data.c +++ b/tools/perf/util/data.c @@ -136,3 +136,44 @@ ssize_t perf_data_file__write(struct perf_data_file *file, { return writen(file->fd, buf, size); } + +int perf_data_file__switch(struct perf_data_file *file, + const char *postfix, + size_t pos, bool at_exit) +{ + char *new_filepath; + int ret; + + if (check_pipe(file)) + return -EINVAL; + if (perf_data_file__is_read(file)) + return -EINVAL; + + if (asprintf(&new_filepath, "%s.%s", file->path, postfix) < 0) + return -ENOMEM; + + /* + * Only fire a warning, don't return error, continue fill + * original file. + */ + if (rename(file->path, new_filepath)) + pr_warning("Failed to rename %s to %s\n", file->path, new_filepath); + + if (!at_exit) { + close(file->fd); + ret = perf_data_file__open(file); + if (ret < 0) + goto out; + + if (lseek(file->fd, pos, SEEK_SET) == (off_t)-1) { + ret = -errno; + pr_debug("Failed to lseek to %zu: %s", + pos, strerror(errno)); + goto out; + } + } + ret = file->fd; +out: + free(new_filepath); + return ret; +} diff --git a/tools/perf/util/data.h b/tools/perf/util/data.h index 2b15d0c95c7f..ae510ce16cb1 100644 --- a/tools/perf/util/data.h +++ b/tools/perf/util/data.h @@ -46,5 +46,14 @@ int perf_data_file__open(struct perf_data_file *file); void perf_data_file__close(struct perf_data_file *file); ssize_t perf_data_file__write(struct perf_data_file *file, void *buf, size_t size); - +/* + * If at_exit is set, only rename current perf.data to + * perf.data., continue write on original file. + * Set at_exit when flushing the last output. + * + * Return value is fd of new output. + */ +int perf_data_file__switch(struct perf_data_file *file, + const char *postfix, + size_t pos, bool at_exit); #endif /* __PERF_DATA_H */ -- 2.20.1