diff options
Diffstat (limited to 'recipes-core/swupd-client/swupd-client/0001-downloads-minimize-syscalls-to-improve-performance.patch')
| -rw-r--r-- | recipes-core/swupd-client/swupd-client/0001-downloads-minimize-syscalls-to-improve-performance.patch | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/recipes-core/swupd-client/swupd-client/0001-downloads-minimize-syscalls-to-improve-performance.patch b/recipes-core/swupd-client/swupd-client/0001-downloads-minimize-syscalls-to-improve-performance.patch new file mode 100644 index 0000000..59875b7 --- /dev/null +++ b/recipes-core/swupd-client/swupd-client/0001-downloads-minimize-syscalls-to-improve-performance.patch @@ -0,0 +1,186 @@ +From 9bc713b7ed0dba91304c5d7ed4905f5924ad8e42 Mon Sep 17 00:00:00 2001 +From: Patrick Ohly <patrick.ohly@intel.com> +Date: Thu, 14 Apr 2016 11:03:31 +0200 +Subject: [PATCH 1/3] downloads: minimize syscalls to improve performance + +The previous approach was to open/fdopen/fclose the file for each +chunk that gets passed from curl. This incurrs a huge performance hit +when close() triggers a hashing of the file content on systems where +integrity protection via IMA is enabled. + +Now the file is opened only once and kept open until the download is +complete. In addition, the unnecessary usage of C file IO is avoided. + +The semantic is changed as little as possible: +- file gets created only after the first chunk of data arrived +- file descriptors do not leak to child processes (O_CLOEXEC) +- data gets appended to existing files (via O_APPEND, used + to keep the code simple and avoid an additional lseek) +- data gets flushed explicitly for each chunk (via fdatasync(), + which somewhat approximates the effect that an explicit + close() may have had) + +As an additional improvement, failures during close() are checked. To +keep error handling as much as before, the completion function which has +the close() takes the current curl error code and replaces it if it +encounters a write error. + +[v2 of the patch with fixes by Dmitry Rozhkov, see https://github.com/pohly/swupd-client/pull/1] + +Signed-off-by: Patrick Ohly <patrick.ohly@intel.com> +--- + include/swupd.h | 3 +++ + src/curl.c | 63 ++++++++++++++++++++++++++++++++++++++++----------------- + src/download.c | 8 +++++++- + 3 files changed, 54 insertions(+), 20 deletions(-) + +diff --git a/include/swupd.h b/include/swupd.h +index 14e65ab..3bac8b2 100644 +--- a/include/swupd.h ++++ b/include/swupd.h +@@ -89,6 +89,7 @@ struct file { + int last_change; + struct update_stat stat; + ++ unsigned int fd_valid : 1; + unsigned int is_dir : 1; + unsigned int is_file : 1; + unsigned int is_link : 1; +@@ -109,6 +110,7 @@ struct file { + + char *staging; /* output name used during download & staging */ + CURL *curl; /* curl handle if downloading */ ++ int fd; /* file written into during downloading, unset when fd_valid is false */ + }; + + extern bool download_only; +@@ -199,6 +201,7 @@ extern void swupd_curl_set_current_version(int v); + extern void swupd_curl_set_requested_version(int v); + extern double swupd_query_url_content_size(char *url); + extern size_t swupd_download_file(void *ptr, size_t size, size_t nmemb, void *userdata); ++extern CURLcode swupd_download_file_complete(CURLcode curl_ret, struct file *file); + extern int swupd_curl_get_file(const char *url, char *filename, struct file *file, + struct version_container *tmp_version, bool pack); + #define SWUPD_CURL_LOW_SPEED_LIMIT 1 +diff --git a/src/curl.c b/src/curl.c +index b14193b..cab1ef2 100644 +--- a/src/curl.c ++++ b/src/curl.c +@@ -165,35 +165,57 @@ size_t swupd_download_file(void *ptr, size_t size, size_t nmemb, void *userdata) + const char *outfile; + int fd; + FILE *f; +- size_t written; ++ size_t written, remaining; + + outfile = file->staging; ++ if (file->fd_valid) { ++ fd = file->fd; ++ } else { ++ fd = open(outfile, O_CREAT | O_RDWR | O_CLOEXEC | O_APPEND, 00600); ++ if (fd < 0) { ++ fprintf(stderr, "Cannot open file for write \\*outfile=\"%s\",strerror=\"%s\"*\\\n", ++ outfile, strerror(errno)); ++ return -1; ++ } ++ file->fd = fd; ++ file->fd_valid = 1; ++ } + +- fd = open(outfile, O_CREAT | O_RDWR, 00600); +- if (fd < 0) { +- printf("Error: Cannot open %s for write: %s\n", +- outfile, strerror(errno)); +- return -1; ++ /* handle short writes with repeated write() calls */ ++ for (remaining = size * nmemb; remaining; remaining -= written) { ++ written = write(fd, ptr, size*nmemb); ++ if (written < 0) { ++ if (errno == EINTR) { ++ written = 0; ++ continue; ++ } ++ fprintf(stderr, "write error \\*outfile=\"%s\",strerror=\"%s\"*\\\n", ++ outfile, strerror(errno)); ++ return -1; ++ } + } + +- f = fdopen(fd, "a"); +- if (!f) { +- printf("Error: Cannot fdopen %s for write: %s\n", +- outfile, strerror(errno)); +- close(fd); ++ if (fdatasync(fd)) { ++ fprintf(stderr, "fdatasync \\*outfile=\"%s\",strerror=\"%s\"*\\\n", outfile, strerror(errno)); + return -1; + } + +- written = fwrite(ptr, size * nmemb, 1, f); +- +- fflush(f); +- fclose(f); ++ return size*nmemb; ++} + +- if (written != 1) { +- return -1; ++CURLcode swupd_download_file_complete(CURLcode curl_ret, struct file *file) ++{ ++ if (file->fd_valid) { ++ if (close(file->fd)) { ++ fprintf(stderr, "Cannot close file after write \\*outfile=\"%s\",strerror=\"%s\"*\\\n", ++ file->staging, strerror(errno)); ++ if (curl_ret == CURLE_OK) { ++ curl_ret = CURLE_WRITE_ERROR; ++ } ++ } ++ file->fd_valid = 0; + } +- +- return size * nmemb; ++ return curl_ret; + } + + /* Download a single file SYNCHRONOUSLY +@@ -281,6 +303,9 @@ int swupd_curl_get_file(const char *url, char *filename, struct file *file, + } + + exit: ++ if (local) { ++ curl_ret = swupd_download_file_complete(curl_ret, local); ++ } + if (curl_ret == CURLE_OK) { + /* curl command succeeded, download might've failed, let our caller handle */ + switch (ret) { +diff --git a/src/download.c b/src/download.c +index 6d81d81..c4a7a07 100644 +--- a/src/download.c ++++ b/src/download.c +@@ -164,6 +164,7 @@ static void free_curl_list_data(void *data) + { + struct file *file = (struct file *)data; + CURL *curl = file->curl; ++ (void) swupd_download_file_complete(CURLE_OK, file); + if (curl != NULL) { + curl_multi_remove_handle(mcurl, curl); + curl_easy_cleanup(curl); +@@ -368,9 +369,14 @@ static int perform_curl_io_and_complete(int *left) + continue; + } + ++ /* Get error code from easy handle and augment it if ++ * completing the download encounters further problems. */ ++ curl_ret = msg->data.result; ++ curl_ret = swupd_download_file_complete(curl_ret, file); ++ + /* The easy handle may have an error set, even if the server returns + * HTTP 200, so retry the download for this case. */ +- if (ret == 200 && msg->data.result != CURLE_OK) { ++ if (ret == 200 && curl_ret != CURLE_OK) { + printf("Error for %s download: %s\n", file->hash, + curl_easy_strerror(msg->data.result)); + failed = list_prepend_data(failed, file); +-- +2.1.4 + |