MINOR: quic: duplicate glitches FE option on BE side

Previously, QUIC glitches support was only implemented for frontend
side. Extend this so that the option can be specified separately both on
frontend and backend sides. Function _qcc_report_glitch() now retrieves
the relevant max value based on connection side.

In addition to this, option has been renamed to use "fe/be" prefixes.
This is part of the current serie of commits which unify QUIC settings.
Older options are deprecated and will be removed on 3.5 release.

doc/configuration.txt

@@ -1888,11 +1888,13 @@ The following keywords are supported in the "global" section :
    - tune.pool-high-fd-ratio
    - tune.pool-low-fd-ratio
    - tune.pt.zero-copy-forwarding
+   - tune.quic.be.sec.glitches-threshold
    - tune.quic.cc-hystart
    - tune.quic.cc.cubic.min-losses
    - tune.quic.disable-tx-pacing
    - tune.quic.disable-udp-gso
-   - tune.quic.frontend.glitches-threshold
+   - tune.quic.fe.sec.glitches-threshold
+   - tune.quic.frontend.glitches-threshold (deprecated)
    - tune.quic.frontend.max-data-size
    - tune.quic.frontend.max-idle-timeout
    - tune.quic.frontend.max-streams-bidi
@@ -4079,8 +4081,8 @@ tune.glitches.kill.cpu-usage <number>
   twice the usually observed CPU usage, or the commonly observed CPU usage plus
   half the idle one (i.e. if CPU commonly reaches 60%, setting 80 here can make
   sense). This parameter has no effect without tune.h2.fe.glitches-threshold or
-  tune.quic.frontend.glitches-threshold. See also the global parameters
+  tune.quic.fe.sec.glitches-threshold. See also the global parameters
-  "tune.h2.fe.glitches-threshold" and "tune.quic.frontend.glitches-threshold".
+  "tune.h2.fe.glitches-threshold" and "tune.quic.fe.sec.glitches-threshold".
 
 tune.h1.zero-copy-fwd-recv { on | off }
   Enables ('on') of disabled ('off') the zero-copy receives of data for the H1
@@ -4727,20 +4729,26 @@ tune.quic.disable-udp-gso
   transfer. It may be useful to disable it on developers suggestion when
   suspecting an issue on emission.
 
-tune.quic.frontend.glitches-threshold <number>
+tune.quic.be.sec.glitches-threshold <number>
-  Sets the threshold for the number of glitches on a frontend connection, where
+tune.quic.fe.sec.glitches-threshold <number>
-  that connection will automatically be killed. This allows to automatically
+  Sets the threshold for the number of glitches per connection either on
-  kill misbehaving connections without having to write explicit rules for them.
+  frontend or backend side, where that connection will automatically be killed.
-  The default value is zero, indicating that no threshold is set so that no
+  This allows to automatically kill misbehaving connections without having to
-  event will cause a connection to be closed. Beware that some QUIC clients may
+  write explicit rules for them. The default value is zero, indicating that no
-  occasionally cause a few glitches over long lasting connection, so any non-
+  threshold is set so that no event will cause a connection to be closed.
-  zero value here should probably be in the hundreds or thousands to be
+  Beware that some QUIC clients may occasionally cause a few glitches over long
-  effective without affecting slightly bogus clients. It is also possible to
+  lasting connection, so any non- zero value here should probably be in the
-  only kill connections when the CPU usage crosses a certain level, by using
+  hundreds or thousands to be effective without affecting slightly bogus
-  "tune.glitches.kill.cpu-usage".
+  clients. It is also possible to only kill connections when the CPU usage
+  crosses a certain level, by using "tune.glitches.kill.cpu-usage".
 
   See also: fc_glitches, tune.glitches.kill.cpu-usage
 
+tune.quic.frontend.glitches-threshold <number> (deprecated)
+  This keyword has been deprecated in 3.3 and will be removed in 3.5. It is
+  part of the streamlining process apply on QUIC configuration. If used, this
+  setting will only be applied on frontend connections.
+
 tune.quic.frontend.max-data-size <size>
   This setting is the hard limit for the number of data bytes in flight over a
   QUIC frontend connection. It is reused as the value for the initial_max_data

include/haproxy/global-t.h

@@ -217,7 +217,6 @@ struct global {
 #ifdef USE_QUIC
 		unsigned int quic_backend_max_idle_timeout;
 		unsigned int quic_frontend_max_idle_timeout;
-		unsigned int quic_frontend_glitches_threshold;
 		unsigned int quic_frontend_max_data;
 		unsigned int quic_frontend_max_streams_bidi;
 		uint64_t quic_frontend_max_tx_mem;

include/haproxy/quic_tune-t.h

@@ -15,11 +15,13 @@
 
 struct quic_tune {
 	struct {
+		uint sec_glitches_threshold;
 		uint opts;    /* QUIC_TUNE_FE_* options specific to FE side */
 		uint fb_opts; /* QUIC_TUNE_FB_* options shared by both side */
 	} fe;
 
 	struct {
+		uint sec_glitches_threshold;
 		uint fb_opts; /* QUIC_TUNE_FB_* options shared by both side */
 	} be;
 

src/cfgparse-quic.c

@@ -281,6 +281,7 @@ static int cfg_parse_quic_tune_setting(char **args, int section_type,
                                        const struct proxy *defpx,
                                        const char *file, int line, char **err)
 {
+	int ret = 0;
 	unsigned int arg = 0;
 	int prefix_len = strlen("tune.quic.");
 	const char *suffix, *errptr;
@@ -299,8 +300,12 @@ static int cfg_parse_quic_tune_setting(char **args, int section_type,
 	suffix = args[0] + prefix_len;
 	if (strcmp(suffix, "cc.cubic.min-losses") == 0)
 		global.tune.quic_cubic_loss_tol = arg - 1;
-	else if (strcmp(suffix, "frontend.glitches-threshold") == 0)
+	else if (strcmp(suffix, "be.sec.glitches-threshold") == 0 ||
-		global.tune.quic_frontend_glitches_threshold = arg;
+	         strcmp(suffix, "fe.sec.glitches-threshold") == 0) {
+		uint *ptr = (suffix[0] == 'b') ? &quic_tune.be.sec_glitches_threshold :
+		                                 &quic_tune.fe.sec_glitches_threshold;
+		*ptr = arg;
+	}
 	else if (strcmp(suffix, "frontend.max-data-size") == 0) {
 		if ((errptr = parse_size_err(args[1], &arg))) {
 			memprintf(err, "'%s': unexpected character '%c' in size argument '%s'.",
@@ -356,12 +361,20 @@ static int cfg_parse_quic_tune_setting(char **args, int section_type,
 	}
 	else if (strcmp(suffix, "retry-threshold") == 0)
 		global.tune.quic_retry_threshold = arg;
+
+	/* legacy options */
+	else if (strcmp(suffix, "frontend.glitches-threshold") == 0) {
+		memprintf(err, "'%s' is deprecated in 3.3 and will be removed in 3.5. "
+		               "Please use the newer keyword syntax 'tune.quic.fe.sec.glitches-threshold'.", args[0]);
+		quic_tune.fe.sec_glitches_threshold = arg;
+		ret = 1;
+	}
 	else {
 		memprintf(err, "'%s' keyword not unhandled (please report this bug).", args[0]);
 		return -1;
 	}
 
-	return 0;
+	return ret;
 }
 
 static int cfg_parse_quic_tune_setting0(char **args, int section_type,
@@ -439,7 +452,6 @@ static struct cfg_kw_list cfg_kws = {ILH, {
 	{ CFG_GLOBAL, "tune.quic.socket-owner", cfg_parse_quic_tune_socket_owner },
 	{ CFG_GLOBAL, "tune.quic.cc-hystart", cfg_parse_quic_tune_on_off },
 	{ CFG_GLOBAL, "tune.quic.cc.cubic.min-losses", cfg_parse_quic_tune_setting },
-	{ CFG_GLOBAL, "tune.quic.frontend.glitches-threshold", cfg_parse_quic_tune_setting },
 	{ CFG_GLOBAL, "tune.quic.frontend.max-data-size", cfg_parse_quic_tune_setting },
 	{ CFG_GLOBAL, "tune.quic.frontend.max-streams-bidi", cfg_parse_quic_tune_setting },
 	{ CFG_GLOBAL, "tune.quic.frontend.max-idle-timeout", cfg_parse_quic_time },
@@ -452,6 +464,14 @@ static struct cfg_kw_list cfg_kws = {ILH, {
 	{ CFG_GLOBAL, "tune.quic.disable-tx-pacing", cfg_parse_quic_tune_setting0 },
 	{ CFG_GLOBAL, "tune.quic.disable-udp-gso", cfg_parse_quic_tune_setting0 },
 	{ CFG_GLOBAL, "tune.quic.zero-copy-fwd-send", cfg_parse_quic_tune_on_off },
+
+	{ CFG_GLOBAL, "tune.quic.fe.sec.glitches-threshold", cfg_parse_quic_tune_setting },
+
+	{ CFG_GLOBAL, "tune.quic.be.sec.glitches-threshold", cfg_parse_quic_tune_setting },
+
+	/* legacy options */
+	{ CFG_GLOBAL, "tune.quic.frontend.glitches-threshold", cfg_parse_quic_tune_setting },
+
 	{ 0, NULL, NULL }
 }};
 

src/mux_quic.c

@@ -759,11 +759,7 @@ void qcc_set_error(struct qcc *qcc, int err, int app)
  */
 int _qcc_report_glitch(struct qcc *qcc, int inc)
 {
-	const int max = global.tune.quic_frontend_glitches_threshold;
+	const int max = QUIC_TUNE_FB_CONN_GET(sec_glitches_threshold, qcc->conn);
-
-	/* TODO add a BE limit for glitch counter */
-	if (qcc->flags & QC_CF_IS_BACK)
-		return 0;
 
 	qcc->glitches += inc;
 	if (max && qcc->glitches >= max && !(qcc->flags & QC_CF_ERRL) &&