Add a "vsl_mask" parameter, that allows individual SLT tags to be

suppressed so the never take up space/bandwidth in the VSL.

Reimplement vcl_trace using this:

	param.set vsl_mask +VCL_trace
	param.set vsl_mask -VCL_trace

XXX: doc-update needed

bin/varnishd/Makefile.am

@@ -61,6 +61,7 @@ varnishd_SOURCES = \
 	mgt/mgt_cli.c \
 	mgt/mgt_main.c \
 	mgt/mgt_param.c \
+	mgt/mgt_param_vsl.c \
 	mgt/mgt_pool.c \
 	mgt/mgt_sandbox.c \
 	mgt/mgt_sandbox_solaris.c \

bin/varnishd/cache/cache_shmlog.c

@@ -50,6 +50,18 @@ static uint32_t			*vsl_ptr;
 
 struct VSC_C_main       *VSC_C_main;
 
+static inline int
+vsl_tag_is_masked(enum VSL_tag_e tag)
+{
+	volatile uint8_t *bm = &cache_param->vsl_mask[0];
+	uint8_t b;
+
+	assert(tag < SLT_Reserved);
+	bm += ((unsigned)tag >> 3);
+	b = (0x80 >> ((unsigned)tag & 7));
+	return (*bm & b);
+}
+
 static inline uint32_t
 vsl_w0(uint32_t type, uint32_t length)
 {
@@ -159,6 +171,8 @@ VSL(enum VSL_tag_e tag, uint32_t vxid, const char *fmt, ...)
 	unsigned n, mlen = cache_param->shm_reclen;
 	char buf[mlen];
 
+	if (vsl_tag_is_masked(tag))
+		return;
 	AN(fmt);
 	va_start(ap, fmt);
 
@@ -281,6 +295,8 @@ VSLb(struct vsl_log *vsl, enum VSL_tag_e tag, const char *fmt, ...)
 	va_list ap;
 
 	AN(fmt);
+	if (vsl_tag_is_masked(tag))
+		return;
 	va_start(ap, fmt);
 	wsl(vsl, tag, vsl->wid, fmt, ap);
 	va_end(ap);
@@ -293,6 +309,9 @@ VSLb(struct vsl_log *vsl, enum VSL_tag_e tag, const char *fmt, ...)
 void
 VSLbt(struct vsl_log *vsl, enum VSL_tag_e tag, txt t)
 {
+
+	if (vsl_tag_is_masked(tag))
+		return;
 	wslr(vsl, tag, -1, t);
 }
 

bin/varnishd/cache/cache_vrt.c

@@ -75,7 +75,6 @@ VRT_count(struct req *req, unsigned u)
 	if (req == NULL)
 		return;
 	CHECK_OBJ_NOTNULL(req, REQ_MAGIC);
-	if (cache_param->vcl_trace)
 	VSLb(req->vsl, SLT_VCL_trace, "%u %u.%u", u,
 	    req->vcl->ref[u].line, req->vcl->ref[u].pos);
 }

bin/varnishd/common/params.h

@@ -103,10 +103,6 @@ struct params {
 	ssize_t			fetch_maxchunksize;
 	unsigned		nuke_limit;
 
-
-	/* VCL traces */
-	unsigned		vcl_trace;
-
 	unsigned		accept_filter;
 
 	/* Listen address */
@@ -204,4 +200,6 @@ struct params {
 	struct poolparam	req_pool;
 	struct poolparam	sess_pool;
 	struct poolparam	vbo_pool;
+
+	uint8_t			vsl_mask[256/8];
 };

bin/varnishd/mgt/mgt_param.c

@@ -872,14 +872,6 @@ static const struct parspec input_parspec[] = {
 		"fragmentation.\n",
 		EXPERIMENTAL,
 		"256m", "bytes" },
-	{ "vcl_trace", tweak_bool,  &mgt_param.vcl_trace, 0, 0,
-		"Trace VCL execution in the shmlog.\n"
-		"Enabling this will allow you to see the path each "
-		"request has taken through the VCL program.\n"
-		"This generates a lot of logrecords so it is off by "
-		"default.",
-		0,
-		"off", "bool" },
 	{ "accept_filter", tweak_bool, &mgt_param.accept_filter, 0, 0,
 		"Enable kernel accept-filters, if supported by the kernel.",
 		MUST_RESTART,
@@ -1318,7 +1310,7 @@ mcf_param_show(struct cli *cli, const char * const *av, void *priv)
 				continue;
 		}
 		pp->func(cli, pp, NULL);
-		if (pp->units != NULL)
+		if (pp->units != NULL && *pp->units != '\0')
 			VCLI_Out(cli, " [%s]\n", pp->units);
 		else
 			VCLI_Out(cli, "\n");
@@ -1496,6 +1488,7 @@ MCF_ParamInit(struct cli *cli)
 
 	MCF_AddParams(input_parspec);
 	MCF_AddParams(WRK_parspec);
+	MCF_AddParams(VSL_parspec);
 
 	/* XXX: We do this twice, to get past any interdependencies */
 	MCF_SetDefaults(NULL);

bin/varnishd/mgt/mgt_param.h

@@ -57,5 +57,8 @@ void tweak_timeout_double(struct cli *cli,
     const struct parspec *par, const char *arg);
 void tweak_bytes(struct cli *cli, const struct parspec *par, const char *arg);
 
+/* mgt_param_vsl.c */
+extern const struct parspec VSL_parspec[];
+
 /* mgt_pool.c */
 extern const struct parspec WRK_parspec[];

bin/varnishd/mgt/mgt_param_vsl.c

+/*-
+ * Copyright (c) 2006 Verdens Gang AS
+ * Copyright (c) 2006-2011 Varnish Software AS
+ * All rights reserved.
+ *
+ * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "common/params.h"
+#include "mgt/mgt.h"
+#include "mgt/mgt_param.h"
+
+#include "vav.h"
+#include "vcli.h"
+#include "vcli_common.h"
+#include "vcli_priv.h"
+
+#include "vapi/vsl_int.h"
+
+static const char * const VSL_tags[256] = {
+#  define SLTM(foo,sdesc,ldesc)       [SLT_##foo] = #foo,
+#  include "tbl/vsl_tags.h"
+#  undef SLTM
+};
+
+enum bit_do {BSET, BCLR, BTST};
+
+static int
+vsl_bit(unsigned no, enum bit_do act)
+{
+	volatile uint8_t *bm = &mgt_param.vsl_mask[0];
+	uint8_t b;
+
+	assert(no < (unsigned)SLT_Reserved);
+
+	bm += (no >> 3);
+	b = (0x80 >> (no & 7));
+	if (act == BSET)
+		*bm |= b;
+	else if (act == BCLR)
+		*bm &= ~b;
+	return (*bm & b);
+}
+
+static void
+tweak_vsl_mask(struct cli *cli, const struct parspec *par, const char *arg)
+{
+	int i, n;
+	unsigned j;
+	const char *s;
+	char **av;
+	(void)par;
+
+	if (arg != NULL) {
+		if (!strcmp(arg, "default")) {
+			(void)vsl_bit(SLT_VCL_trace, BSET);
+			(void)vsl_bit(SLT_WorkThread, BSET);
+		} else if (*arg != 0) {
+			av = VAV_Parse(arg, &n, ARGV_COMMA);
+			if (av[0] != NULL) {
+				VCLI_Out(cli, "Cannot parse: %s\n", av[0]);
+				VCLI_SetResult(cli, CLIS_PARAM);
+				return;
+			}
+			for (i = 1; av[i] != NULL; i++) {
+				s = av[i];
+				if (*s != '-' && *s != '+') {
+					VCLI_Out(cli,
+					    "Missing '+' or '-' (%s)\n", s);
+					VCLI_SetResult(cli, CLIS_PARAM);
+					VAV_Free(av);
+					return;
+				}
+				for (j = 0; j < 256; j++)
+					if (VSL_tags[j] != NULL &&
+					    !strcasecmp(s + 1, VSL_tags[j]))
+						break;
+				if (j == 256) {
+					VCLI_Out(cli,
+					    "Unknown VSL tag (%s)\n", s);
+					VCLI_SetResult(cli, CLIS_PARAM);
+					VAV_Free(av);
+					return;
+				}
+				if (s[0] == '+')
+					(void)vsl_bit(j, BCLR);
+				else
+					(void)vsl_bit(j, BSET);
+			}
+			VAV_Free(av);
+		}
+	} else {
+		s = "";
+		for (j = 0; j < 256; j++) {
+			if (vsl_bit(j, BTST)) {
+				VCLI_Out(cli, "%s-%s", s, VSL_tags[j]);
+				s = ",";
+			}
+		}
+		if (*s == '\0')
+			VCLI_Out(cli, "(all enabled)");
+	}
+}
+
+const struct parspec VSL_parspec[] = {
+	{ "vsl_mask", tweak_vsl_mask, NULL, 0, 0,
+		"Mask individual VSL messages from being logged",
+		0, "default", "" },
+	{ NULL, NULL, NULL }
+};

bin/varnishtest/tests/c00005.vtc

@@ -9,7 +9,7 @@ server s1 {
 	txresp -body "2222\n"
 } -start
 
-varnish v1 -arg "-p vcl_trace=on" -vcl+backend {
+varnish v1 -arg "-p vsl_mask=+VCL_trace" -vcl+backend {
 	acl acl1 {
 		"localhost";
 	}

bin/varnishtest/tests/c00054.vtc

+varnishtest "SLT masking"
+
+
+server s1 {
+	rxreq
+	txresp
+} -start
+
+varnish v1 -vcl+backend {} -start
+
+varnish v1 -cliok "param.show vsl_mask"
+varnish v1 -cliok "param.set vsl_mask +VCL_trace"
+varnish v1 -cliok "param.show vsl_mask"
+varnish v1 -cliok "param.set vsl_mask -WorkThread,-TTL"
+varnish v1 -cliok "param.show vsl_mask"
+varnish v1 -cliok "param.set vsl_mask +WorkThread"
+varnish v1 -clierr 106 "param.set vsl_mask FooBar"
+varnish v1 -clierr 106 "param.set vsl_mask -FooBar"
+
+client c1 {
+	txreq
+	rxresp
+} -run