diff options
Diffstat (limited to 'lib/dynamic_debug.c')
| -rw-r--r-- | lib/dynamic_debug.c | 270 |
1 files changed, 187 insertions, 83 deletions
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index dcdade39e47..310c753cf83 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -60,6 +60,7 @@ struct ddebug_iter { static DEFINE_MUTEX(ddebug_lock); static LIST_HEAD(ddebug_tables); static int verbose = 0; +module_param(verbose, int, 0644); /* Return the last part of a pathname */ static inline const char *basename(const char *path) @@ -68,12 +69,24 @@ static inline const char *basename(const char *path) return tail ? tail+1 : path; } +/* Return the path relative to source root */ +static inline const char *trim_prefix(const char *path) +{ + int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c"); + + if (strncmp(path, __FILE__, skip)) + skip = 0; /* prefix mismatch, don't skip */ + + return path + skip; +} + static struct { unsigned flag:8; char opt_char; } opt_array[] = { { _DPRINTK_FLAGS_PRINT, 'p' }, { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, { _DPRINTK_FLAGS_INCL_TID, 't' }, + { _DPRINTK_FLAGS_NONE, '_' }, }; /* format a string into buf[] which describes the _ddebug's flags */ @@ -83,58 +96,74 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf, char *p = buf; int i; - BUG_ON(maxlen < 4); + BUG_ON(maxlen < 6); for (i = 0; i < ARRAY_SIZE(opt_array); ++i) if (dp->flags & opt_array[i].flag) *p++ = opt_array[i].opt_char; if (p == buf) - *p++ = '-'; + *p++ = '_'; *p = '\0'; return buf; } +#define vpr_info_dq(q, msg) \ +do { \ + if (verbose) \ + /* trim last char off format print */ \ + pr_info("%s: func=\"%s\" file=\"%s\" " \ + "module=\"%s\" format=\"%.*s\" " \ + "lineno=%u-%u", \ + msg, \ + q->function ? q->function : "", \ + q->filename ? q->filename : "", \ + q->module ? q->module : "", \ + (int)(q->format ? strlen(q->format) - 1 : 0), \ + q->format ? q->format : "", \ + q->first_lineno, q->last_lineno); \ +} while (0) + /* - * Search the tables for _ddebug's which match the given - * `query' and apply the `flags' and `mask' to them. Tells - * the user which ddebug's were changed, or whether none - * were matched. + * Search the tables for _ddebug's which match the given `query' and + * apply the `flags' and `mask' to them. Returns number of matching + * callsites, normally the same as number of changes. If verbose, + * logs the changes. Takes ddebug_lock. */ -static void ddebug_change(const struct ddebug_query *query, - unsigned int flags, unsigned int mask) +static int ddebug_change(const struct ddebug_query *query, + unsigned int flags, unsigned int mask) { int i; struct ddebug_table *dt; unsigned int newflags; unsigned int nfound = 0; - char flagbuf[8]; + char flagbuf[10]; /* search for matching ddebugs */ mutex_lock(&ddebug_lock); list_for_each_entry(dt, &ddebug_tables, link) { /* match against the module name */ - if (query->module != NULL && - strcmp(query->module, dt->mod_name)) + if (query->module && strcmp(query->module, dt->mod_name)) continue; for (i = 0 ; i < dt->num_ddebugs ; i++) { struct _ddebug *dp = &dt->ddebugs[i]; /* match against the source filename */ - if (query->filename != NULL && + if (query->filename && strcmp(query->filename, dp->filename) && - strcmp(query->filename, basename(dp->filename))) + strcmp(query->filename, basename(dp->filename)) && + strcmp(query->filename, trim_prefix(dp->filename))) continue; /* match against the function */ - if (query->function != NULL && + if (query->function && strcmp(query->function, dp->function)) continue; /* match against the format */ - if (query->format != NULL && - strstr(dp->format, query->format) == NULL) + if (query->format && + !strstr(dp->format, query->format)) continue; /* match against the line number range */ @@ -151,13 +180,9 @@ static void ddebug_change(const struct ddebug_query *query, if (newflags == dp->flags) continue; dp->flags = newflags; - if (newflags) - dp->enabled = 1; - else - dp->enabled = 0; if (verbose) - pr_info("changed %s:%d [%s]%s %s\n", - dp->filename, dp->lineno, + pr_info("changed %s:%d [%s]%s =%s\n", + trim_prefix(dp->filename), dp->lineno, dt->mod_name, dp->function, ddebug_describe_flags(dp, flagbuf, sizeof(flagbuf))); @@ -167,6 +192,8 @@ static void ddebug_change(const struct ddebug_query *query, if (!nfound && verbose) pr_info("no matches for query\n"); + + return nfound; } /* @@ -186,8 +213,10 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords) buf = skip_spaces(buf); if (!*buf) break; /* oh, it was trailing whitespace */ + if (*buf == '#') + break; /* token starts comment, skip rest of line */ - /* Run `end' over a word, either whitespace separated or quoted */ + /* find `end' of word, whitespace separated or quoted */ if (*buf == '"' || *buf == '\'') { int quote = *buf++; for (end = buf ; *end && *end != quote ; end++) @@ -199,8 +228,8 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords) ; BUG_ON(end == buf); } - /* Here `buf' is the start of the word, `end' is one past the end */ + /* `buf' is start of word, `end' is one past its end */ if (nwords == maxwords) return -EINVAL; /* ran out of words[] before bytes */ if (*end) @@ -279,6 +308,19 @@ static char *unescape(char *str) return str; } +static int check_set(const char **dest, char *src, char *name) +{ + int rc = 0; + + if (*dest) { + rc = -EINVAL; + pr_err("match-spec:%s val:%s overridden by %s", + name, *dest, src); + } + *dest = src; + return rc; +} + /* * Parse words[] as a ddebug query specification, which is a series * of (keyword, value) pairs chosen from these possibilities: @@ -290,11 +332,15 @@ static char *unescape(char *str) * format <escaped-string-to-find-in-format> * line <lineno> * line <first-lineno>-<last-lineno> // where either may be empty + * + * Only 1 of each type is allowed. + * Returns 0 on success, <0 on error. */ static int ddebug_parse_query(char *words[], int nwords, struct ddebug_query *query) { unsigned int i; + int rc; /* check we have an even number of words */ if (nwords % 2 != 0) @@ -303,41 +349,43 @@ static int ddebug_parse_query(char *words[], int nwords, for (i = 0 ; i < nwords ; i += 2) { if (!strcmp(words[i], "func")) - query->function = words[i+1]; + rc = check_set(&query->function, words[i+1], "func"); else if (!strcmp(words[i], "file")) - query->filename = words[i+1]; + rc = check_set(&query->filename, words[i+1], "file"); else if (!strcmp(words[i], "module")) - query->module = words[i+1]; + rc = check_set(&query->module, words[i+1], "module"); else if (!strcmp(words[i], "format")) - query->format = unescape(words[i+1]); + rc = check_set(&query->format, unescape(words[i+1]), + "format"); else if (!strcmp(words[i], "line")) { char *first = words[i+1]; char *last = strchr(first, '-'); + if (query->first_lineno || query->last_lineno) { + pr_err("match-spec:line given 2 times\n"); + return -EINVAL; + } if (last) *last++ = '\0'; if (parse_lineno(first, &query->first_lineno) < 0) return -EINVAL; - if (last != NULL) { + if (last) { /* range <first>-<last> */ - if (parse_lineno(last, &query->last_lineno) < 0) + if (parse_lineno(last, &query->last_lineno) + < query->first_lineno) { + pr_err("last-line < 1st-line\n"); return -EINVAL; + } } else { query->last_lineno = query->first_lineno; } } else { - if (verbose) - pr_err("unknown keyword \"%s\"\n", words[i]); + pr_err("unknown keyword \"%s\"\n", words[i]); return -EINVAL; } + if (rc) + return rc; } - - if (verbose) - pr_info("q->function=\"%s\" q->filename=\"%s\" " - "q->module=\"%s\" q->format=\"%s\" q->lineno=%u-%u\n", - query->function, query->filename, - query->module, query->format, query->first_lineno, - query->last_lineno); - + vpr_info_dq(query, "parsed"); return 0; } @@ -375,8 +423,6 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp, if (i < 0) return -EINVAL; } - if (flags == 0) - return -EINVAL; if (verbose) pr_info("flags=0x%x\n", flags); @@ -405,7 +451,7 @@ static int ddebug_exec_query(char *query_string) unsigned int flags = 0, mask = 0; struct ddebug_query query; #define MAXWORDS 9 - int nwords; + int nwords, nfound; char *words[MAXWORDS]; nwords = ddebug_tokenize(query_string, words, MAXWORDS); @@ -417,8 +463,47 @@ static int ddebug_exec_query(char *query_string) return -EINVAL; /* actually go and implement the change */ - ddebug_change(&query, flags, mask); - return 0; + nfound = ddebug_change(&query, flags, mask); + vpr_info_dq((&query), (nfound) ? "applied" : "no-match"); + + return nfound; +} + +/* handle multiple queries in query string, continue on error, return + last error or number of matching callsites. Module name is either + in param (for boot arg) or perhaps in query string. +*/ +static int ddebug_exec_queries(char *query) +{ + char *split; + int i, errs = 0, exitcode = 0, rc, nfound = 0; + + for (i = 0; query; query = split) { + split = strpbrk(query, ";\n"); + if (split) + *split++ = '\0'; + + query = skip_spaces(query); + if (!query || !*query || *query == '#') + continue; + + if (verbose) + pr_info("query %d: \"%s\"\n", i, query); + + rc = ddebug_exec_query(query); + if (rc < 0) { + errs++; + exitcode = rc; + } else + nfound += rc; + i++; + } + pr_info("processed %d queries, with %d matches, %d errs\n", + i, nfound, errs); + + if (exitcode) + return exitcode; + return nfound; } #define PREFIX_SIZE 64 @@ -452,7 +537,8 @@ static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf) pos += snprintf(buf + pos, remaining(pos), "%s:", desc->function); if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) - pos += snprintf(buf + pos, remaining(pos), "%d:", desc->lineno); + pos += snprintf(buf + pos, remaining(pos), "%d:", + desc->lineno); if (pos - pos_after_tid) pos += snprintf(buf + pos, remaining(pos), " "); if (pos >= PREFIX_SIZE) @@ -527,14 +613,16 @@ EXPORT_SYMBOL(__dynamic_netdev_dbg); #endif -static __initdata char ddebug_setup_string[1024]; +#define DDEBUG_STRING_SIZE 1024 +static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE]; + static __init int ddebug_setup_query(char *str) { - if (strlen(str) >= 1024) { + if (strlen(str) >= DDEBUG_STRING_SIZE) { pr_warn("ddebug boot param string too large\n"); return 0; } - strcpy(ddebug_setup_string, str); + strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE); return 1; } @@ -544,25 +632,33 @@ __setup("ddebug_query=", ddebug_setup_query); * File_ops->write method for <debugfs>/dynamic_debug/conrol. Gathers the * command text from userspace, parses and executes it. */ +#define USER_BUF_PAGE 4096 static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, size_t len, loff_t *offp) { - char tmpbuf[256]; + char *tmpbuf; int ret; if (len == 0) return 0; - /* we don't check *offp -- multiple writes() are allowed */ - if (len > sizeof(tmpbuf)-1) + if (len > USER_BUF_PAGE - 1) { + pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE); return -E2BIG; - if (copy_from_user(tmpbuf, ubuf, len)) + } + tmpbuf = kmalloc(len + 1, GFP_KERNEL); + if (!tmpbuf) + return -ENOMEM; + if (copy_from_user(tmpbuf, ubuf, len)) { + kfree(tmpbuf); return -EFAULT; + } tmpbuf[len] = '\0'; if (verbose) pr_info("read %d bytes from userspace\n", (int)len); - ret = ddebug_exec_query(tmpbuf); - if (ret) + ret = ddebug_exec_queries(tmpbuf); + kfree(tmpbuf); + if (ret < 0) return ret; *offp += len; @@ -668,7 +764,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) { struct ddebug_iter *iter = m->private; struct _ddebug *dp = p; - char flagsbuf[8]; + char flagsbuf[10]; if (verbose) pr_info("called m=%p p=%p\n", m, p); @@ -679,10 +775,10 @@ static int ddebug_proc_show(struct seq_file *m, void *p) return 0; } - seq_printf(m, "%s:%u [%s]%s %s \"", - dp->filename, dp->lineno, - iter->table->mod_name, dp->function, - ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf))); + seq_printf(m, "%s:%u [%s]%s =%s \"", + trim_prefix(dp->filename), dp->lineno, + iter->table->mod_name, dp->function, + ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf))); seq_escape(m, dp->format, "\t\r\n\""); seq_puts(m, "\"\n"); @@ -708,10 +804,11 @@ static const struct seq_operations ddebug_proc_seqops = { }; /* - * File_ops->open method for <debugfs>/dynamic_debug/control. Does the seq_file - * setup dance, and also creates an iterator to walk the _ddebugs. - * Note that we create a seq_file always, even for O_WRONLY files - * where it's not needed, as doing so simplifies the ->release method. + * File_ops->open method for <debugfs>/dynamic_debug/control. Does + * the seq_file setup dance, and also creates an iterator to walk the + * _ddebugs. Note that we create a seq_file always, even for O_WRONLY + * files where it's not needed, as doing so simplifies the ->release + * method. */ static int ddebug_proc_open(struct inode *inode, struct file *file) { @@ -846,33 +943,40 @@ static int __init dynamic_debug_init(void) int ret = 0; int n = 0; - if (__start___verbose != __stop___verbose) { - iter = __start___verbose; - modname = iter->modname; - iter_start = iter; - for (; iter < __stop___verbose; iter++) { - if (strcmp(modname, iter->modname)) { - ret = ddebug_add_module(iter_start, n, modname); - if (ret) - goto out_free; - n = 0; - modname = iter->modname; - iter_start = iter; - } - n++; + if (__start___verbose == __stop___verbose) { + pr_warn("_ddebug table is empty in a " + "CONFIG_DYNAMIC_DEBUG build"); + return 1; + } + iter = __start___verbose; + modname = iter->modname; + iter_start = iter; + for (; iter < __stop___verbose; iter++) { + if (strcmp(modname, iter->modname)) { + ret = ddebug_add_module(iter_start, n, modname); + if (ret) + goto out_free; + n = 0; + modname = iter->modname; + iter_start = iter; } - ret = ddebug_add_module(iter_start, n, modname); + n++; } + ret = ddebug_add_module(iter_start, n, modname); + if (ret) + goto out_free; /* ddebug_query boot param got passed -> set it up */ if (ddebug_setup_string[0] != '\0') { - ret = ddebug_exec_query(ddebug_setup_string); - if (ret) + ret = ddebug_exec_queries(ddebug_setup_string); + if (ret < 0) pr_warn("Invalid ddebug boot param %s", ddebug_setup_string); else - pr_info("ddebug initialized with string %s", - ddebug_setup_string); + pr_info("%d changes by ddebug_query\n", ret); + + /* keep tables even on ddebug_query parse error */ + ret = 0; } out_free: |