[PATCH 12/16] dyndbg: add filter parameter to ddebug_parse_flags

From: Jim Cromie <jim.cromie@gmail.com>
To: jbaron@akamai.com, linux-kernel@vger.kernel.org,
	akpm@linuxfoundation.org, gregkh@linuxfoundation.org
Cc: linux@rasmusvillemoes.dk, Jim Cromie <jim.cromie@gmail.com>
Subject: [PATCH 12/16] dyndbg: add filter parameter to ddebug_parse_flags
Date: Fri,  5 Jun 2020 10:26:41 -0600	[thread overview]
Message-ID: <20200605162645.289174-13-jim.cromie@gmail.com> (raw)
In-Reply-To: <20200605162645.289174-1-jim.cromie@gmail.com>

Add a new *filter param to ddebug_parse_flags(), allowing it to
communicate optional filter flags back to its caller: ddebug_change()

Also, ddebug_change doesn't alter any of its arguments, including its 2
new ones; mods, filter.  Say so by adding const modifier to them.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
 lib/dynamic_debug.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 2ecabfd3f432..32eb7d9545c7 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -146,7 +146,8 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
  * logs the changes.  Takes ddebug_lock.
  */
 static int ddebug_change(const struct ddebug_query *query,
-			 struct flagsettings *mods)
+			 const struct flagsettings *mods,
+			 const struct flagsettings *filter)
 {
 	int i;
 	struct ddebug_table *dt;
@@ -444,7 +445,10 @@ static int ddebug_read_flags(const char *str, struct flagsettings *f)
  * flags fields of matched _ddebug's.  Returns 0 on success
  * or <0 on error.
  */
-static int ddebug_parse_flags(const char *str, struct flagsettings *mods)
+
+static int ddebug_parse_flags(const char *str,
+			      struct flagsettings *mods,
+			      struct flagsettings *filter)
 {
 	int op;
 
@@ -476,7 +480,9 @@ static int ddebug_parse_flags(const char *str, struct flagsettings *mods)
 		mods->flags = 0;
 		break;
 	}
-	vpr_info("*flagsp=0x%x *maskp=0x%x\n", mods->flags, mods->mask);
+
+	vpr_info("mods:flags=0x%x,mask=0x%x filter:flags=0x%x,mask=0x%x\n",
+		 mods->flags, mods->mask, filter->flags, filter->mask);
 
 	return 0;
 }
@@ -484,6 +490,7 @@ static int ddebug_parse_flags(const char *str, struct flagsettings *mods)
 static int ddebug_exec_query(char *query_string, const char *modname)
 {
 	struct flagsettings mods = {};
+	struct flagsettings filter = {};
 	struct ddebug_query query;
 #define MAXWORDS 9
 	int nwords, nfound;
@@ -495,7 +502,7 @@ static int ddebug_exec_query(char *query_string, const char *modname)
 		return -EINVAL;
 	}
 	/* check flags 1st (last arg) so query is pairs of spec,val */
-	if (ddebug_parse_flags(words[nwords-1], &mods)) {
+	if (ddebug_parse_flags(words[nwords-1], &mods, &filter)) {
 		pr_err("flags parse failed\n");
 		return -EINVAL;
 	}
@@ -504,7 +511,7 @@ static int ddebug_exec_query(char *query_string, const char *modname)
 		return -EINVAL;
 	}
 	/* actually go and implement the change */
-	nfound = ddebug_change(&query, &mods);
+	nfound = ddebug_change(&query, &mods, &filter);
 	vpr_info_dq(&query, nfound ? "applied" : "no-match");
 
 	return nfound;
-- 
2.26.2

