[PATCH 1/2] sched_deadline: Accommodate new location of HRTICK file in kernel
From: John Kacur <jkacur@redhat.com>
Date: 2021-07-23 19:16:36
Subsystem:
the rest · Maintainer:
Linus Torvalds
Newer kernels rename /sys/kernel/debug/sched_features to /sys/kernel/debug/sched/features Modify sched_deadline tests to look for the new file and if that fails look for the old file name These functions are based on ones in stalld, and stalld itself has functions based on the sched_deadline programs in rt-tests Signed-off-by: John Kacur <jkacur@redhat.com> --- src/sched_deadline/cyclicdeadline.c | 65 ++++++++++++++++++++++------- src/sched_deadline/deadline_test.c | 61 +++++++++++++++++++++------ 2 files changed, 100 insertions(+), 26 deletions(-)
diff --git a/src/sched_deadline/cyclicdeadline.c b/src/sched_deadline/cyclicdeadline.c
index 8447424273ee..4a38ec2274c9 100644
--- a/src/sched_deadline/cyclicdeadline.c
+++ b/src/sched_deadline/cyclicdeadline.c@@ -230,12 +230,53 @@ found: mark_fd = open(files, O_WRONLY); } +/* + * Return true if file exists + */ +static int check_file_exists(char *path) +{ + int ret; + struct stat st; + + ret = !stat(path, &st); + + return ret; + +} + +/* + * Return 0 on success + */ + +static int fill_sched_features(char *path) +{ + int ret; + const char *debugfs; + + debugfs = find_debugfs(); + if (strlen(debugfs) == 0) + return -1; + + snprintf(path, MAX_PATH, "%s/sched/features", debugfs); + ret = check_file_exists(path); + if (ret) + return 0; + + snprintf(path, MAX_PATH, "%s/sched_features", debugfs); + ret = check_file_exists(path); + if (ret) + return 0; + + memset(path, 0, MAX_PATH); + + return ret; + +} + static int setup_hr_tick(void) { - const char *debugfs = find_debugfs(); - char files[strlen(debugfs) + strlen("/sched_features") + 1]; + char path[MAX_PATH]; char buf[500]; - struct stat st; static int set = 0; char *p; int ret;
@@ -244,27 +285,23 @@ static int setup_hr_tick(void) if (set) return 1; - set = 1; - if (strlen(debugfs) == 0) - return 0; - - sprintf(files, "%s/sched_features", debugfs); - ret = stat(files, &st); - if (ret < 0) + ret = fill_sched_features(path); + if (ret) return 0; - fd = open(files, O_RDWR); - perror(files); - if (fd < 0) + fd = open(path, O_RDWR); + if (fd < 0) { + perror(path); return 0; + } len = sizeof(buf); ret = read(fd, buf, len); if (ret < 0) { - perror(files); + perror(path); close(fd); return 0; }
diff --git a/src/sched_deadline/deadline_test.c b/src/sched_deadline/deadline_test.c
index 395c2370f69a..c1e890319895 100644
--- a/src/sched_deadline/deadline_test.c
+++ b/src/sched_deadline/deadline_test.c@@ -368,6 +368,49 @@ found: mark_fd = open(files, O_WRONLY); } +/* + * Return true if file exists + */ +static int check_file_exists(char *path) +{ + int ret; + struct stat st; + + ret = !stat(path, &st); + + return ret; + +} + +/* + * Return 0 on success + */ + +static int fill_sched_features(char *path) +{ + int ret; + const char *debugfs; + + debugfs = find_debugfs(); + if (strlen(debugfs) == 0) + return -1; + + snprintf(path, MAX_PATH, "%s/sched/features", debugfs); + ret = check_file_exists(path); + if (ret) + return 0; + + snprintf(path, MAX_PATH, "%s/sched_features", debugfs); + ret = check_file_exists(path); + if (ret) + return 0; + + memset(path, 0, MAX_PATH); + + return ret; + +} + /** * setup_hr_tick - Enable the HRTICK in sched_features (if available) *
@@ -381,10 +424,8 @@ found: */ static int setup_hr_tick(void) { - const char *debugfs = find_debugfs(); - char files[strlen(debugfs) + strlen("/sched_features") + 1]; + char path[MAX_PATH]; char buf[500]; - struct stat st; static int set = 0; char *p; int ret;
@@ -396,17 +437,13 @@ static int setup_hr_tick(void) set = 1; - if (strlen(debugfs) == 0) - return 0; - - sprintf(files, "%s/sched_features", debugfs); - ret = stat(files, &st); - if (ret < 0) + ret = fill_sched_features(path); + if (ret) return 0; - fd = open(files, O_RDWR); + fd = open(path, O_RDWR); if (fd < 0) { - perror(files); + perror(path); return 0; }
@@ -414,7 +451,7 @@ static int setup_hr_tick(void) ret = read(fd, buf, len); if (ret < 0) { - perror(files); + perror(path); close(fd); return 0; }
--
2.31.1