From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932092Ab1F1HMf (ORCPT ); Tue, 28 Jun 2011 03:12:35 -0400 Received: from mail-iw0-f174.google.com ([209.85.214.174]:34558 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756715Ab1F1HKZ (ORCPT ); Tue, 28 Jun 2011 03:10:25 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=qiBX9cHq8SLLVHv1yew0BVsvz2C6wUkZGd+mnRMGzkxeWgbJEMted0Ef9A6QsR9ik1 z7/wTlAUhb7SRnMSBV3Wd1jZg4lRo63R1S3y3TOdtacJAEDRmjpuYor5Q0aIJtoA9HNn FN17QzSB8VE6fmnHM3j8H2hnwi+jbO9ClEKBU= From: Jim Cromie To: linux-kernel@vger.kernel.org Cc: gnb@fmeh.org, jbaron@redhat.com, bvanassche@acm.org, gregkh@suse.de, Jim Cromie Subject: [PATCH 09/11] dynamic_debug: add_to_pending() saves non-matching queries for later. Date: Tue, 28 Jun 2011 01:09:50 -0600 Message-Id: <1309244992-2305-10-git-send-email-jim.cromie@gmail.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1309244992-2305-1-git-send-email-jim.cromie@gmail.com> References: <1309244992-2305-1-git-send-email-jim.cromie@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When a query/rule doesnt match, call add_to_pending(new function) to copy the query off the stack, into a (new) struct pending_query, and add to pending_queries (new) list. Patch adds: /sys/module/dynamic_debug/parameters/ verbose - rw, added previously, here for completeness pending_ct - ro, shows current count of pending queries pending_max - rw, set max pending, further pending queries are rejected With this and previous patches, queries added on the boot-line which do not match (because module is not built-in, and thus not present yet) are added to pending_queries. IE, with these boot-line additions: dynamic_debug.verbose=1 ddebug_query="module scx200_hrt +p" Kernel will log the following: ddebug_exec_queries: query 0: "module scx200_hrt +p" ddebug_tokenize: split into words: "module" "scx200_hrt" "+p" ddebug_parse_query: parsed q->function="(null)" q->filename="(null)" q->module="scx200_hrt" q->format="(null)" q->lineno=0-0 ddebug_parse_flags: op='+' ddebug_parse_flags: flags=0x1 ddebug_parse_flags: *flagsp=0x1 *maskp=0xffffffff ddebug_exec_query: nfound 0 on q->function="(null)" q->filename="(null)" q->module="scx200_hrt" q->format="(null)" q->lineno=0-0 ddebug_add_to_pending: add to pending: q->function="(null)" q->filename="(null)" q->module="scx200_hrt" q->format="(null)" q->lineno=0-0 ddebug_add_to_pending: ddebug: query saved as pending 1 Signed-off-by: Jim Cromie --- lib/dynamic_debug.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++---- 1 files changed, 72 insertions(+), 6 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 9b8b1e8..37d0275 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -53,6 +53,16 @@ struct ddebug_query { unsigned int first_lineno, last_lineno; }; +struct pending_query { + struct list_head link; + struct ddebug_query query; + char filename[100]; + char module[30]; + char function[50]; + char format[200]; + unsigned int flags, mask; +}; + struct ddebug_iter { struct ddebug_table *table; unsigned int idx; @@ -61,7 +71,13 @@ struct ddebug_iter { static DEFINE_MUTEX(ddebug_lock); static LIST_HEAD(ddebug_tables); static int verbose = 0; -module_param(verbose, int, 0744); +module_param(verbose, int, 0644); + +/* legal but inapplicable queries, save and test against new modules */ +static LIST_HEAD(pending_queries); +static int pending_ct, pending_max = 100; +module_param(pending_ct, int, 0444); +module_param(pending_max, int, 0644); /* Return the last part of a pathname */ static inline const char *basename(const char *path) @@ -96,6 +112,56 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf, return buf; } +static char prbuf_query[300]; + +static char *show_ddebug_query(const struct ddebug_query *q) +{ + sprintf(prbuf_query, + "q->function=\"%s\" q->filename=\"%s\" " + "q->module=\"%s\" q->format=\"%s\" q->lineno=%u-%u", + q->function, q->filename, q->module, q->format, + q->first_lineno, q->last_lineno); + + return prbuf_query; +} + +/* copy query off stack, save flags & mask, and store in pending-list */ +static void add_to_pending(const struct ddebug_query *query, + unsigned int flags, unsigned int mask) +{ + struct pending_query *pq; + + if (pending_ct >= pending_max) { + pr_warn("ddebug: no matches for query, pending is full\n"); + return; + } + if (verbose) + pr_info("add to pending: %s\n", show_ddebug_query(query)); + + pending_ct++; + pq = kzalloc(sizeof(struct pending_query), GFP_KERNEL); + + /* copy non-null match-specs into allocd mem, update pointers */ + if (query->module) + pq->query.module = strcpy(pq->module, query->module); + if (query->function) + pq->query.function = strcpy(pq->function, query->function); + if (query->filename) + pq->query.filename = strcpy(pq->filename, query->filename); + if (query->format) + pq->query.format = strcpy(pq->format, query->format); + + pq->flags = flags; + pq->mask = mask; + + mutex_lock(&ddebug_lock); + list_add(&pq->link, &pending_queries); + mutex_unlock(&ddebug_lock); + + if (verbose) + pr_info("ddebug: query saved as pending %d\n", pending_ct); +} + /* * Search the tables for _ddebug's which match the given * `query' and apply the `flags' and `mask' to them. Tells @@ -348,11 +414,7 @@ static int ddebug_parse_query(char *words[], int nwords, } 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); + pr_info("parsed %s\n", show_ddebug_query(query)); return 0; } @@ -437,6 +499,10 @@ static int ddebug_exec_query(char *query_string) /* actually go and implement the change */ nfound = ddebug_change(&query, flags, mask); + pr_info("nfound %d on %s\n", nfound, show_ddebug_query(&query)); + if (!nfound) + ddebug_add_to_pending(&query, flags, mask); + return 0; } -- 1.7.4.1