diff options
| -rw-r--r-- | Documentation/dynamic-debug-howto.txt | 23 | ||||
| -rw-r--r-- | lib/dynamic_debug.c | 73 |
2 files changed, 66 insertions, 30 deletions
diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt index 378b5d1bf436..74e6c7782678 100644 --- a/Documentation/dynamic-debug-howto.txt +++ b/Documentation/dynamic-debug-howto.txt @@ -12,7 +12,7 @@ dynamically enabled per-callsite. Dynamic debug has even more useful features: * Simple query language allows turning on and off debugging statements by - matching any combination of: + matching any combination of 0 or 1 of: - source filename - function name @@ -79,31 +79,24 @@ Command Language Reference ========================== At the lexical level, a command comprises a sequence of words separated -by whitespace characters. Note that newlines are treated as word -separators and do *not* end a command or allow multiple commands to -be done together. So these are all equivalent: +by spaces or tabs. So these are all equivalent: nullarbor:~ # echo -c 'file svcsock.c line 1603 +p' > <debugfs>/dynamic_debug/control nullarbor:~ # echo -c ' file svcsock.c line 1603 +p ' > <debugfs>/dynamic_debug/control -nullarbor:~ # echo -c 'file svcsock.c\nline 1603 +p' > - <debugfs>/dynamic_debug/control nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > <debugfs>/dynamic_debug/control -Commands are bounded by a write() system call. If you want to do -multiple commands you need to do a separate "echo" for each, like: +Command submissions are bounded by a write() system call. +Multiple commands can be written together, separated by ';' or '\n'. -nullarbor:~ # echo 'file svcsock.c line 1603 +p' > /proc/dprintk ;\ -> echo 'file svcsock.c line 1563 +p' > /proc/dprintk + ~# echo "func pnpacpi_get_resources +p; func pnp_assign_mem +p" \ + > <debugfs>/dynamic_debug/control -or even like: +If your query set is big, you can batch them too: -nullarbor:~ # ( -> echo 'file svcsock.c line 1603 +p' ;\ -> echo 'file svcsock.c line 1563 +p' ;\ -> ) > /proc/dprintk + ~# cat query-batch-file > <debugfs>/dynamic_debug/control At the syntactical level, a command comprises a sequence of match specifications, followed by a flags change specification. diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 93fc5d500cd5..310c753cf83e 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -124,13 +124,13 @@ do { \ } 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; @@ -192,6 +192,8 @@ static void ddebug_change(const struct ddebug_query *query, if (!nfound && verbose) pr_info("no matches for query\n"); + + return nfound; } /* @@ -449,7 +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); @@ -461,8 +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 @@ -615,9 +656,9 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, if (verbose) pr_info("read %d bytes from userspace\n", (int)len); - ret = ddebug_exec_query(tmpbuf); + ret = ddebug_exec_queries(tmpbuf); kfree(tmpbuf); - if (ret) + if (ret < 0) return ret; *offp += len; @@ -927,13 +968,15 @@ static int __init dynamic_debug_init(void) /* 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: |