}
int libcfs_debug_msg(struct libcfs_debug_msg_data *msgdata,
- const char *format, ...)
+ const char *format, ...)
{
- struct cfs_trace_cpu_data *tcd = NULL;
- struct ptldebug_header header = {0};
- struct cfs_trace_page *tage;
- /* string_buf is used only if tcd != NULL, and is always set then */
- char *string_buf = NULL;
- char *debug_buf;
- int known_size;
- int needed = 85; /* average message length */
- int max_nob;
- va_list ap;
- int i;
- int remain;
- int mask = msgdata->msg_mask;
- char *file = (char *)msgdata->msg_file;
+ struct cfs_trace_cpu_data *tcd = NULL;
+ struct ptldebug_header header = {0};
+ struct cfs_trace_page *tage;
+ /* string_buf is used only if tcd != NULL, and is always set then */
+ char *string_buf = NULL;
+ char *debug_buf;
+ int known_size;
+ int needed = 85; /* seeded with average message length */
+ int max_nob;
+ va_list ap;
+ int retry;
+ int mask = msgdata->msg_mask;
+ char *file = (char *)msgdata->msg_file;
struct cfs_debug_limit_state *cdls = msgdata->msg_cdls;
- if (strchr(file, '/'))
- file = strrchr(file, '/') + 1;
+ if (strchr(file, '/'))
+ file = strrchr(file, '/') + 1;
- tcd = cfs_trace_get_tcd();
+ tcd = cfs_trace_get_tcd();
- /* cfs_trace_get_tcd() grabs a lock, which disables preemption and
- * pins us to a particular CPU. This avoids an smp_processor_id()
- * warning on Linux when debugging is enabled. */
- cfs_set_ptldebug_header(&header, msgdata, CDEBUG_STACK());
+ /* cfs_trace_get_tcd() grabs a lock, which disables preemption and
+ * pins us to a particular CPU. This avoids an smp_processor_id()
+ * warning on Linux when debugging is enabled.
+ */
+ cfs_set_ptldebug_header(&header, msgdata, CDEBUG_STACK());
- if (tcd == NULL) /* arch may not log in IRQ context */
- goto console;
+ if (!tcd) /* arch may not log in IRQ context */
+ goto console;
- if (tcd->tcd_cur_pages == 0)
- header.ph_flags |= PH_FLAG_FIRST_RECORD;
+ if (tcd->tcd_cur_pages == 0)
+ header.ph_flags |= PH_FLAG_FIRST_RECORD;
- if (tcd->tcd_shutting_down) {
- cfs_trace_put_tcd(tcd);
- tcd = NULL;
- goto console;
- }
+ if (tcd->tcd_shutting_down) {
+ cfs_trace_put_tcd(tcd);
+ tcd = NULL;
+ goto console;
+ }
known_size = strlen(file) + 1;
- if (msgdata->msg_fn)
- known_size += strlen(msgdata->msg_fn) + 1;
+ if (msgdata->msg_fn)
+ known_size += strlen(msgdata->msg_fn) + 1;
- if (libcfs_debug_binary)
- known_size += sizeof(header);
+ if (libcfs_debug_binary)
+ known_size += sizeof(header);
- /*/
- * '2' used because vsnprintf return real size required for output
- * _without_ terminating NULL.
- * if needed is to small for this format.
- */
- for (i = 0; i < 2; i++) {
- tage = cfs_trace_get_tage(tcd, needed + known_size + 1);
- if (tage == NULL) {
+ /*
+ * May perform an additional pass to update 'needed' and increase
+ * tage buffer size to match vsnprintf reported size required
+ * On the second pass (retry=1) use vscnprintf [which returns
+ * number of bytes written not including the terminating nul]
+ * to clarify `needed` is used as number of bytes written
+ * for the remainder of this function
+ */
+ for (retry = 0; retry < 2; retry++) {
+ tage = cfs_trace_get_tage(tcd, needed + known_size + 1);
+ if (!tage) {
if (needed + known_size > PAGE_SIZE)
- mask |= D_ERROR;
+ mask |= D_ERROR;
- cfs_trace_put_tcd(tcd);
- tcd = NULL;
- goto console;
- }
+ cfs_trace_put_tcd(tcd);
+ tcd = NULL;
+ goto console;
+ }
string_buf = (char *)page_address(tage->page) +
tage->used + known_size;
goto console;
}
- needed = 0;
- remain = max_nob - needed;
- if (remain < 0)
- remain = 0;
-
va_start(ap, format);
- needed += vsnprintf(string_buf + needed, remain,
- format, ap);
+ if (retry)
+ needed = vscnprintf(string_buf, max_nob, format, ap);
+ else
+ needed = vsnprintf(string_buf, max_nob, format, ap);
va_end(ap);
- if (needed < max_nob) /* well. printing ok.. */
- break;
- }
+ if (needed < max_nob) /* well. printing ok.. */
+ break;
+ }
+ /* `needed` is actual bytes written to string_buf */
if (*(string_buf + needed - 1) != '\n') {
pr_info("Lustre: format at %s:%d:%s doesn't end in newline\n",
file, msgdata->msg_line, msgdata->msg_fn);
file, msgdata->msg_line, msgdata->msg_fn);
}
- header.ph_len = known_size + needed;
+ header.ph_len = known_size + needed;
debug_buf = (char *)page_address(tage->page) + tage->used;
- if (libcfs_debug_binary) {
- memcpy(debug_buf, &header, sizeof(header));
- tage->used += sizeof(header);
- debug_buf += sizeof(header);
- }
+ if (libcfs_debug_binary) {
+ memcpy(debug_buf, &header, sizeof(header));
+ tage->used += sizeof(header);
+ debug_buf += sizeof(header);
+ }
- strcpy(debug_buf, file);
- tage->used += strlen(file) + 1;
- debug_buf += strlen(file) + 1;
+ strlcpy(debug_buf, file, PAGE_SIZE - tage->used);
+ tage->used += strlen(file) + 1;
+ debug_buf += strlen(file) + 1;
- if (msgdata->msg_fn) {
- strcpy(debug_buf, msgdata->msg_fn);
- tage->used += strlen(msgdata->msg_fn) + 1;
- debug_buf += strlen(msgdata->msg_fn) + 1;
- }
+ if (msgdata->msg_fn) {
+ strlcpy(debug_buf, msgdata->msg_fn, PAGE_SIZE - tage->used);
+ tage->used += strlen(msgdata->msg_fn) + 1;
+ debug_buf += strlen(msgdata->msg_fn) + 1;
+ }
- __LASSERT(debug_buf == string_buf);
+ __LASSERT(debug_buf == string_buf);
- tage->used += needed;
+ tage->used += needed;
__LASSERT(tage->used <= PAGE_SIZE);
console:
- if ((mask & libcfs_printk) == 0) {
- /* no console output requested */
- if (tcd != NULL)
- cfs_trace_put_tcd(tcd);
- return 1;
- }
+ if ((mask & libcfs_printk) == 0) {
+ /* no console output requested */
+ if (tcd != NULL)
+ cfs_trace_put_tcd(tcd);
+ return 1;
+ }
if (cdls != NULL) {
if (libcfs_console_ratelimit &&
cdls->cdls_next = (jiffies + cdls->cdls_delay) | 1;
}
- if (tcd != NULL) {
- cfs_print_to_console(&header, mask, string_buf, needed, file,
- msgdata->msg_fn);
- cfs_trace_put_tcd(tcd);
- } else {
- string_buf = cfs_trace_get_console_buffer();
-
- needed = 0;
- remain = CFS_TRACE_CONSOLE_BUFFER_SIZE - needed;
- if (remain > 0) {
- va_start(ap, format);
- needed += vsnprintf(string_buf+needed, remain,
- format, ap);
- va_end(ap);
- }
+ if (tcd) {
+ cfs_print_to_console(&header, mask, string_buf, needed, file,
+ msgdata->msg_fn);
+ cfs_trace_put_tcd(tcd);
+ } else {
+ string_buf = cfs_trace_get_console_buffer();
+
+ va_start(ap, format);
+ needed = vscnprintf(string_buf, CFS_TRACE_CONSOLE_BUFFER_SIZE,
+ format, ap);
+ va_end(ap);
- cfs_print_to_console(&header, mask,
- string_buf, needed, file, msgdata->msg_fn);
+ cfs_print_to_console(&header, mask,
+ string_buf, needed, file, msgdata->msg_fn);
put_cpu();
- }
+ }
- if (cdls != NULL && cdls->cdls_count != 0) {
- string_buf = cfs_trace_get_console_buffer();
+ if (cdls != NULL && cdls->cdls_count != 0) {
+ string_buf = cfs_trace_get_console_buffer();
- needed = snprintf(string_buf, CFS_TRACE_CONSOLE_BUFFER_SIZE,
- "Skipped %d previous similar message%s\n",
- cdls->cdls_count,
- (cdls->cdls_count > 1) ? "s" : "");
+ needed = scnprintf(string_buf, CFS_TRACE_CONSOLE_BUFFER_SIZE,
+ "Skipped %d previous similar message%s\n",
+ cdls->cdls_count,
+ (cdls->cdls_count > 1) ? "s" : "");
/* Do not allow print this to TTY */
cfs_print_to_console(&header, mask & ~D_TTY, string_buf,
needed, file, msgdata->msg_fn);
put_cpu();
- cdls->cdls_count = 0;
- }
+ cdls->cdls_count = 0;
+ }
- return 0;
+ return 0;
}
EXPORT_SYMBOL(libcfs_debug_msg);