The return value type of read/write function from unistd.h is ssize_t. It's signed normaly, and return -1 on error. Fix incorrect use in the function read_ras_event_all_cpus().
BTW, make setting buffer_percent as a separate function.
Fixes: 94750bcf9309 ("rasdaemon: Fix poll() on per_cpu trace_pipe_raw blocks indefinitely") Signed-off-by: Xiaofei Tan tanxiaofei@huawei.com --- ras-events.c | 45 ++++++++++++++++++++++++++++++--------------- 1 file changed, 30 insertions(+), 15 deletions(-)
diff --git a/ras-events.c b/ras-events.c index 2662467..d041828 100644 --- a/ras-events.c +++ b/ras-events.c @@ -368,10 +368,37 @@ static int get_num_cpus(struct ras_events *ras) #endif }
+static int set_buffer_percent(struct ras_events *ras, int percent) +{ + char buf[16]; + ssize_t size; + int res = 0; + int fd; + + fd = open_trace(ras, "buffer_percent", O_WRONLY); + if (fd >= 0) { + /* For the backward compatibility to the old kernels, do not return + * if fail to set the buffer_percent. + */ + snprintf(buf, sizeof(buf), "%d", percent); + size = write(fd, buf, strlen(buf)); + if (size <= 0) { + log(TERM, LOG_WARNING, "can't write to buffer_percent\n"); + res = -1; + } + close(fd); + } else { + log(TERM, LOG_WARNING, "Can't open buffer_percent\n"); + res = -1; + } + + return res; +} + static int read_ras_event_all_cpus(struct pthread_data *pdata, unsigned n_cpus) { - unsigned size; + ssize_t size; unsigned long long time_stamp; void *data; int ready, i, count_nready; @@ -383,8 +410,6 @@ static int read_ras_event_all_cpus(struct pthread_data *pdata, int warnonce[n_cpus]; char pipe_raw[PATH_MAX]; int legacy_kernel = 0; - int fd; - char buf[16]; #if 0 int need_sleep = 0; #endif @@ -411,18 +436,8 @@ static int read_ras_event_all_cpus(struct pthread_data *pdata, * Set buffer_percent to 0 so that poll() will return immediately * when the trace data is available in the ras per_cpu trace pipe_raw */ - fd = open_trace(pdata[0].ras, "buffer_percent", O_WRONLY); - if (fd >= 0) { - /* For the backward compatibility to the old kernels, do not return - * if fail to set the buffer_percent. - */ - snprintf(buf, sizeof(buf), "0"); - size = write(fd, buf, strlen(buf)); - if (size <= 0) - log(TERM, LOG_WARNING, "can't write to buffer_percent\n"); - close(fd); - } else - log(TERM, LOG_WARNING, "Can't open buffer_percent\n"); + if (set_buffer_percent(pdata[0].ras, 0)) + log(TERM, LOG_WARNING, "Set buffer_percent failed\n");
for (i = 0; i < (n_cpus + 1); i++) fds[i].fd = -1;