[202412] [FRR] Add support for 514 BGP sessions (sonic-net#1034)

**Add support for 512 BGP sessions**

Backport sonic-net#22390 to
202412

| Patch | Upstream Commit |
|-------|----------------|
| 0044-zebra-Prevent-starvation-in-dplane_thread_loop.patch |
[6faad863](FRRouting/frr@6faad86)
|
| 0083-bgpd-fix-vty-output-of-evpn-route-target-AS4.patch |
[20b3ab48](FRRouting/frr@20b3ab4)
|
| 0084-zebra-Ensure-dplane-does-not-send-work-back-to-maste.patch |
[c4115522](FRRouting/frr@c411552)
|
| 0085-zebra-Limit-mutex-for-obuf-to-when-we-access-obuf.patch |
[c58da10d](FRRouting/frr@c58da10)
|
| 0086-bgpd-backpressure-Fix-to-pop-items-off-zebra_announc.patch |
[898852f](FRRouting/frr@898852f)
|
| 0087-zebra-fnc-obuf-could-be-accessed-without-a-lock.patch |
[e7a1fbbcf](FRRouting/frr@e7a1fbb)
|
| 0088-zebra-Add-show-fpm-status-json-command.patch |
[0a9e8ef49](FRRouting/frr@0a9e8ef)
|
| 0089-doc-Add-show-fpm-status-json-command-to-documentatio.patch |
[a0c4fe2ca](FRRouting/frr@a0c4fe2)
|
| 0090-zebra-avoid-a-race-during-FPM-dplane-plugin-shutdown.patch |
[277784f](FRRouting/frr@277784f)
|
| 0091-zebra-add-nexthop-counter-to-show-zebra-dplane-comma.patch |
[e36e570c](FRRouting/frr@e36e570)
|
| 0092-zebra-Installation-success-should-not-set-NHG-as-val.patch |
[910b2c5a](FRRouting/frr@910b2c5)
|
| 0093-zebra-When-reinstalling-a-NHG-set-REINSTALL-flag.patch |
[b2ade8e](FRRouting/frr@b2ade8e)
|
| 0094-zebra-Conslidate-zebra_nhg_set_valid-invalid-functio.patch |
[6ee9cc68](FRRouting/frr@8f76afd)
|
| 0095-zebra-Properly-note-that-a-nhg-s-nexthop-has-gone-do.patch |
[3b9428a7](FRRouting/frr@1bbbcf0)
|
| 0096-zebra-be-consistent-about-v6-nexthops-for-v4-routes.patch |
[c93bc371](FRRouting/frr@0221ed2)
|
| 0097-lib-zebra-Modify-nexthop_cmp-to-allow-you-to-use-wei.patch |
[75268f01](FRRouting/frr@b8e24a0)
|
| 0098-zebra-Create-Singleton-nhg-s-without-weights.patch |
[ae4a1315](FRRouting/frr@c20fa97)
|
| 0099-zebra-Allow-blackhole-singleton-nexthops-to-be-v6.patch |
[ae397ad9](FRRouting/frr@f90989d)
|
| 0100-zebra-Allow-for-initial-deny-of-installation-of-nhe-.patch |
[4bf2c11f](FRRouting/frr@0c72a78)
|
| 0101-zebra-Properly-note-that-a-nhg-s-nexthop-has-gone-do.patch |
[892e8179](FRRouting/frr@1bbbcf0)
|
| 0102-zebra-Reinstall-nexthop-when-interface-comes-back-up.patch |
[279f427c](FRRouting/frr@3be8b48)
|
| 0103-zebra-Attempt-to-reuse-NHG-after-interface-up-and-ro.patch |
[98d56711](FRRouting/frr@f02d76f)
|
| 0104-zebra-Expose-_route_entry_dump_nh-so-it-can-be-used.patch |
[4fb44993](FRRouting/frr@ce166ca)
|
| 0105-zebra-Fix-resetting-valid-flags-for-NHG-dependents.patch |
[6e95686b](FRRouting/frr@54ec9f3)
|
| 0106-zebra-Fix-leaked-nhe.patch |
[a84d2bc0](FRRouting/frr@97fa24e)
|
| 0107-zebra-Uninstall-NHG-in-some-situations.patch |
[d1cba73a](FRRouting/frr@4c16694)
|
| 0108-zebra-Optimize-invoking-nhg-compare-func.patch |
[0faa70a5](FRRouting/frr@e77954e)
|
| 0109-zebra-Nexthops-need-to-be-ACTIVE-in-some-cases.patch |
[df56b92b](FRRouting/frr@b61424a)
|
| 0110-zebra-On-Nexthop-install-failure-don-t-set-Installat.patch |
[4b2b1a9a](FRRouting/frr@ec6a000)
|
| 0111-zebra-Bring-up-514-BGP-neighbor-sessions.patch |
[ea399e15](FRRouting/frr@6a75d33)
|
| 0112-lib-Add-support-for-stream-buffer-to-expand.patch |
[65b3ee4e](FRRouting/frr@c0c46ba)
|
| 0113-zebra-zebra-crash-for-zapi-stream.patch |
[c122afdb](FRRouting/frr@6fe9092)
|
| 0114-bgpd-Replace-per-peer-connection-error-with-per-bgp.patch |
[10c127bc](FRRouting/frr@6a5962e)
|
| 0115-bgpd-remove-apis-from-bgp_route.h.patch |
[1d5a8a20](FRRouting/frr@020245b)
|
| 0116-bgpd-batch-peer-connection-error-clearing.patch |
[4baa9f2d](FRRouting/frr@58f924d)
|
| 0117-zebra-move-peer-conn-error-list-to-connection-struct.patch |
[411abd6b](FRRouting/frr@6206e7e)
|
| 0118-bgpd-Allow-batch-clear-to-do-partial-work-and-contin.patch |
[b68be906](FRRouting/frr@c527882)
|
| 0119-zebra-send-v6-fast-RA-at-faster-interval.patch |
[c8f12a4f](FRRouting/frr#18451) |
| 0120-lib-add-option-to-start-stop-wheel-timer.patch |
[ca0adcdd](FRRouting/frr#18451) |
| 0121-bgpd-Paths-received-from-shutdown-peer-not-deleted.patch |
[2cbfc7ec](FRRouting/frr@d2bec7a)
|

**Verification:**
Verified the changes on topology with scaled BGP tests

---------

Signed-off-by: Vivek Reddy <[email protected]>
Signed-off-by: Vivek <[email protected]>

Author: vivekrnv

src/sonic-frr/patch/0044-zebra-Modify-dplane-loop-to-allow-backpressure-to-fi.patch

@@ -1,8 +1,7 @@
-From 4671ddf4920553b663fda129f7c4366839347645 Mon Sep 17 00:00:00 2001
+From e6e096f2507e76c375ba9d6b20c05af0b61ce2cd Mon Sep 17 00:00:00 2001
 From: Donald Sharp <[email protected]>
 Date: Wed, 12 Jun 2024 14:14:48 -0400
-Subject: [PATCH 3/5] zebra: Modify dplane loop to allow backpressure to filter
- up
+Subject: [PATCH] zebra: Modify dplane loop to allow backpressure to filter up
 
 Currently when the dplane_thread_loop is run, it moves contexts
 from the dg_update_list and puts the contexts on the input queue
@@ -30,11 +29,12 @@ context system and memory will not go out of control.
 
 Signed-off-by: Donald Sharp <[email protected]>
 
+
 diff --git a/zebra/zebra_dplane.c b/zebra/zebra_dplane.c
-index c52e032660..f0e1ff6f27 100644
+index 44ee41d8c..0460463bc 100644
 --- a/zebra/zebra_dplane.c
 +++ b/zebra/zebra_dplane.c
-@@ -7155,10 +7155,10 @@ static void dplane_thread_loop(struct thread *event)
+@@ -7279,10 +7279,10 @@ static void dplane_thread_loop(struct event *event)
  {
  	struct dplane_ctx_list_head work_list;
  	struct dplane_ctx_list_head error_list;
@@ -47,7 +47,7 @@ index c52e032660..f0e1ff6f27 100644
  	bool reschedule = false;
 
  	/* Capture work limit per cycle */
-@@ -7182,18 +7182,48 @@ static void dplane_thread_loop(struct thread *event)
+@@ -7306,18 +7306,48 @@ static void dplane_thread_loop(struct event *event)
  	/* Locate initial registered provider */
  	prov = dplane_prov_list_first(&zdplane_info.dg_providers);
 
@@ -104,7 +104,7 @@ index c52e032660..f0e1ff6f27 100644
  	DPLANE_UNLOCK();
 
  	atomic_fetch_sub_explicit(&zdplane_info.dg_routes_queued, counter,
-@@ -7212,8 +7242,9 @@ static void dplane_thread_loop(struct thread *event)
+@@ -7336,8 +7366,9 @@ static void dplane_thread_loop(struct event *event)
  		 * items.
  		 */
  		if (IS_ZEBRA_DEBUG_DPLANE_DETAIL)
@@ -116,7 +116,7 @@ index c52e032660..f0e1ff6f27 100644
 
  		/* Capture current provider id in each context; check for
  		 * error status.
-@@ -7271,18 +7302,61 @@ static void dplane_thread_loop(struct thread *event)
+@@ -7395,18 +7426,61 @@ static void dplane_thread_loop(struct event *event)
  		if (!zdplane_info.dg_run)
  			break;
 
@@ -185,8 +185,8 @@ index c52e032660..f0e1ff6f27 100644
  		dplane_provider_unlock(prov);
 
  		if (counter >= limit)
-@@ -7293,7 +7367,7 @@ static void dplane_thread_loop(struct thread *event)
- 				   counter, dplane_provider_get_name(prov));
+@@ -7422,7 +7496,7 @@ static void dplane_thread_loop(struct event *event)
+ 		}
 
  		/* Locate next provider */
 -		prov = dplane_prov_list_next(&zdplane_info.dg_providers, prov);

src/sonic-frr/patch/0044-zebra-Prevent-starvation-in-dplane_thread_loop.patch

@@ -0,0 +1,49 @@
+From 6faad863f30d29157e4c675ad956e3ccd38991a7 Mon Sep 17 00:00:00 2001
+From: Donald Sharp <[email protected]>
+Date: Fri, 14 Jun 2024 13:36:51 -0400
+Subject: [PATCH] zebra: Prevent starvation in dplane_thread_loop
+
+When removing a large number of routes, the linux kernel can take the
+cpu for an extended amount of time, leaving a situation where FRR
+detects a starvation event.
+
+r1# sharp install routes 10.0.0.0 nexthop 192.168.44.33 1000000 repeat 10
+2024-06-14 12:55:49.365 [NTFY] sharpd: [M7Q4P-46WDR] vty[5]@# sharp install routes 10.0.0.0 nexthop 192.168.44.33 1000000 repeat 10
+2024-06-14 12:55:49.365 [DEBG] sharpd: [YP4TQ-01TYK] Inserting 1000000 routes
+2024-06-14 12:55:57.256 [DEBG] sharpd: [TPHKD-3NYSB] Installed All Items 7.890085
+2024-06-14 12:55:57.256 [DEBG] sharpd: [YJ486-NX5R1] Removing 1000000 routes
+2024-06-14 12:56:07.802 [WARN] zebra: [QH9AB-Y4XMZ][EC 100663314] STARVATION: task dplane_thread_loop (634377bc8f9e) ran for 7078ms (cpu time 220ms)
+2024-06-14 12:56:25.039 [DEBG] sharpd: [WTN53-GK9Y5] Removed all Items 27.783668
+2024-06-14 12:56:25.039 [DEBG] sharpd: [YP4TQ-01TYK] Inserting 1000000 routes
+2024-06-14 12:56:32.783 [DEBG] sharpd: [TPHKD-3NYSB] Installed All Items 7.743524
+2024-06-14 12:56:32.783 [DEBG] sharpd: [YJ486-NX5R1] Removing 1000000 routes
+2024-06-14 12:56:41.447 [WARN] zebra: [QH9AB-Y4XMZ][EC 100663314] STARVATION: task dplane_thread_loop (634377bc8f9e) ran for 5175ms (cpu time 179ms)
+
+Let's modify the loop in dplane_thread_loop such that after a provider
+has been run, check to see if the event should yield, if so, stop
+and reschedule this for the future.
+
+Signed-off-by: Donald Sharp <[email protected]>
+---
+ zebra/zebra_dplane.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/zebra/zebra_dplane.c b/zebra/zebra_dplane.c
+index 06b34da209..3944876439 100644
+--- a/zebra/zebra_dplane.c
++++ b/zebra/zebra_dplane.c
+@@ -7441,6 +7441,11 @@ static void dplane_thread_loop(struct event *event)
+ 			zlog_debug("dplane dequeues %d completed work from provider %s",
+ 				   counter, dplane_provider_get_name(prov));
+ 
++		if (event_should_yield(event)) {
++			reschedule = true;
++			break;
++		}
++
+ 		/* Locate next provider */
+ 		prov = dplane_prov_list_next(&zdplane_info.dg_providers, prov);
+ 	}
+-- 
+2.39.5
+

src/sonic-frr/patch/0045-zebra-Limit-queue-depth-in-dplane_fpm_nl.patch

@@ -1,7 +1,7 @@
-From 50f606c158f6c89abd0d3f531905005d3a48a5b6 Mon Sep 17 00:00:00 2001
+From 1712fbd14dddd542e7aa4b468356abdfe42817d4 Mon Sep 17 00:00:00 2001
 From: Donald Sharp <[email protected]>
 Date: Wed, 12 Jun 2024 15:16:08 -0400
-Subject: [PATCH 4/5] zebra: Limit queue depth in dplane_fpm_nl
+Subject: [PATCH] zebra: Limit queue depth in dplane_fpm_nl
 
 The dplane providers have a concept of input queues
 and output queues.  These queues are chained together
@@ -16,12 +16,15 @@ queue when it is already full.  This will allow the backpressure
 to work appropriately in zebra proper.
 
 Signed-off-by: Donald Sharp <[email protected]>
+---
+ zebra/dplane_fpm_nl.c | 19 +++++++++++++++++++
+ 1 file changed, 19 insertions(+)
 
 diff --git a/zebra/dplane_fpm_nl.c b/zebra/dplane_fpm_nl.c
-index bc9815bb10..4fd42f64a2 100644
+index a054d362f..81f1c9417 100644
 --- a/zebra/dplane_fpm_nl.c
 +++ b/zebra/dplane_fpm_nl.c
-@@ -1560,6 +1560,25 @@ static int fpm_nl_process(struct zebra_dplane_provider *prov)
+@@ -1603,6 +1603,25 @@ static int fpm_nl_process(struct zebra_dplane_provider *prov)
 
  	fnc = dplane_provider_get_data(prov);
  	limit = dplane_provider_get_work_limit(prov);
@@ -36,7 +39,7 @@ index bc9815bb10..4fd42f64a2 100644
 +				   ") of internal work, hold off",
 +				   __func__, cur_queue);
 +		limit = 0;
-+	} else {
++	} else if (cur_queue != 0) {
 +		if (IS_ZEBRA_DEBUG_FPM)
 +			zlog_debug("%s: current queue is %" PRIu64
 +				   ", limiting to lesser amount of %" PRIu64,