Skip to content

Commit

Permalink
northd: lflow-mgr: Reconstruct DPG bitmap on lflow reference unlink.
Browse files Browse the repository at this point in the history 
Signed-off-by: Ilya Maximets <[email protected]>
  • Loading branch information
@igsilya
igsilya committed Feb 8, 2024
1 parent 5ac3a78 commit 8c0f700
Showing 1 changed file with 17 additions and 108 deletions.
125 changes: 17 additions & 108 deletions northd/lflow-mgr.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
#include <config.h>

/* OVS includes */
#include "coverage.h"
#include "include/openvswitch/thread.h"
#include "lib/bitmap.h"
#include "openvswitch/vlog.h"
Expand Down Expand Up @@ -100,12 +101,6 @@ static bool sync_lflow_to_sb(struct ovn_lflow *,
extern int parallelization_state;
extern thread_local size_t thread_lflow_counter;

struct dp_refcnt;
static struct dp_refcnt *dp_refcnt_find(struct hmap *dp_refcnts_map,
size_t dp_index);
static void dp_refcnt_use(struct hmap *dp_refcnts_map, size_t dp_index);
static bool dp_refcnt_release(struct hmap *dp_refcnts_map, size_t dp_index);
static void ovn_lflow_clear_dp_refcnts_map(struct ovn_lflow *);
static struct lflow_ref_node *lflow_ref_node_find(struct hmap *lflow_ref_nodes,
struct ovn_lflow *lflow,
uint32_t lflow_hash);
Expand Down Expand Up @@ -177,9 +172,6 @@ struct ovn_lflow {

struct uuid sb_uuid; /* SB DB row uuid, specified by northd. */
struct ovs_list referenced_by; /* List of struct lflow_ref_node. */
struct hmap dp_refcnts_map; /* Maintains the number of times this ovn_lflow
* is referenced by a given datapath.
* Contains 'struct dp_refcnt' in the map. */
};

/* Logical flow table. */
Expand Down Expand Up @@ -566,6 +558,9 @@ lflow_ref_destroy(struct lflow_ref *lflow_ref)
free(lflow_ref);
}

COVERAGE_DEFINE(ref_unlink_clear)
COVERAGE_DEFINE(ref_unlink_recon)

/* Unlinks the lflows referenced by the 'lflow_ref'.
* For each lflow_ref_node (lrn) in the lflow_ref, it basically clears
* the datapath id (lrn->dp_index) or all the datapath id bits in the
Expand All @@ -578,18 +573,20 @@ lflow_ref_unlink_lflows(struct lflow_ref *lflow_ref)
struct lflow_ref_node *lrn;

HMAP_FOR_EACH (lrn, ref_node, &lflow_ref->lflow_ref_nodes) {
if (lrn->dpgrp_lflow) {
size_t index;
BITMAP_FOR_EACH_1 (index, lrn->dpgrp_bitmap_len,
lrn->dpgrp_bitmap) {
if (dp_refcnt_release(&lrn->lflow->dp_refcnts_map, index)) {
bitmap_set0(lrn->lflow->dpg_bitmap, index);
}
struct lflow_ref_node *lflow_lrn;

COVERAGE_INC(ref_unlink_clear);
memset(lrn->lflow->dpg_bitmap, 0, lrn->dpgrp_bitmap_len);
LIST_FOR_EACH (lflow_lrn, ref_list_node, &lrn->lflow->referenced_by) {
if (lflow_lrn == lrn) {
continue;
}
} else {
if (dp_refcnt_release(&lrn->lflow->dp_refcnts_map,
lrn->dp_index)) {
bitmap_set0(lrn->lflow->dpg_bitmap, lrn->dp_index);
COVERAGE_INC(ref_unlink_recon);
if (lflow_lrn->dpgrp_lflow) {
bitmap_or(lrn->lflow->dpg_bitmap, lflow_lrn->dpgrp_bitmap,
lflow_lrn->dpgrp_bitmap_len);
} else {
bitmap_set1(lrn->lflow->dpg_bitmap, lflow_lrn->dp_index);
}
}

Expand Down Expand Up @@ -691,18 +688,8 @@ lflow_table_add_lflow(struct lflow_table *lflow_table,
if (lrn->dpgrp_lflow) {
lrn->dpgrp_bitmap = bitmap_clone(dp_bitmap, dp_bitmap_len);
lrn->dpgrp_bitmap_len = dp_bitmap_len;

size_t index;
BITMAP_FOR_EACH_1 (index, dp_bitmap_len, dp_bitmap) {
if (bitmap_is_set(lflow->dpg_bitmap, index)) {
dp_refcnt_use(&lflow->dp_refcnts_map, index);
}
}
} else {
lrn->dp_index = od->index;
if (bitmap_is_set(lflow->dpg_bitmap, od->index)) {
dp_refcnt_use(&lflow->dp_refcnts_map, lrn->dp_index);
}
}
ovs_list_insert(&lflow->referenced_by, &lrn->ref_list_node);
hmap_insert(&lflow_ref->lflow_ref_nodes, &lrn->ref_node, hash);
Expand Down Expand Up @@ -863,7 +850,6 @@ ovn_lflow_init(struct ovn_lflow *lflow, struct ovn_datapath *od,
lflow->dpg = NULL;
lflow->where = where;
lflow->sb_uuid = UUID_ZERO;
hmap_init(&lflow->dp_refcnts_map);
ovs_list_init(&lflow->referenced_by);
}

Expand Down Expand Up @@ -939,7 +925,6 @@ ovn_lflow_destroy(struct lflow_table *lflow_table, struct ovn_lflow *lflow)
free(lflow->io_port);
free(lflow->stage_hint);
free(lflow->ctrl_meter);
ovn_lflow_clear_dp_refcnts_map(lflow);
struct lflow_ref_node *lrn;
LIST_FOR_EACH_SAFE (lrn, ref_list_node, &lflow->referenced_by) {
lflow_ref_node_destroy(lrn);
Expand Down Expand Up @@ -1314,82 +1299,6 @@ lflow_ref_sync_lflows__(struct lflow_ref *lflow_ref,
return true;
}

/* Used for the datapath reference counting for a given 'struct ovn_lflow'.
* See the hmap 'dp_refcnts_map in 'struct ovn_lflow'.
* For a given lflow L(M, A) with match - M and actions - A, it can be
* referenced by multiple lflow_refs for the same datapath
* Eg. Two lflow_ref's - op->lflow_ref and op->stateful_lflow_ref of a
* datapath can have a reference to the same lflow L (M, A). In this it
* is important to maintain this reference count so that the sync to the
* SB DB logical_flow is correct. */
struct dp_refcnt {
struct hmap_node key_node;

size_t dp_index; /* datapath index. Also used as hmap key. */
size_t refcnt; /* reference counter. */
};

static struct dp_refcnt *
dp_refcnt_find(struct hmap *dp_refcnts_map, size_t dp_index)
{
struct dp_refcnt *dp_refcnt;
HMAP_FOR_EACH_WITH_HASH (dp_refcnt, key_node, dp_index, dp_refcnts_map) {
if (dp_refcnt->dp_index == dp_index) {
return dp_refcnt;
}
}

return NULL;
}

static void
dp_refcnt_use(struct hmap *dp_refcnts_map, size_t dp_index)
{
struct dp_refcnt *dp_refcnt = dp_refcnt_find(dp_refcnts_map, dp_index);

if (!dp_refcnt) {
dp_refcnt = xmalloc(sizeof *dp_refcnt);
dp_refcnt->dp_index = dp_index;
/* Allocation is happening on the second (!) use. */
dp_refcnt->refcnt = 1;

hmap_insert(dp_refcnts_map, &dp_refcnt->key_node, dp_index);
}

dp_refcnt->refcnt++;
}

/* Decrements the datapath's refcnt from the 'dp_refcnts_map' if it exists
* and returns true if the refcnt is 0 or if the dp refcnt doesn't exist. */
static bool
dp_refcnt_release(struct hmap *dp_refcnts_map, size_t dp_index)
{
struct dp_refcnt *dp_refcnt = dp_refcnt_find(dp_refcnts_map, dp_index);
if (!dp_refcnt) {
return true;
}

if (!--dp_refcnt->refcnt) {
hmap_remove(dp_refcnts_map, &dp_refcnt->key_node);
free(dp_refcnt);
return true;
}

return false;
}

static void
ovn_lflow_clear_dp_refcnts_map(struct ovn_lflow *lflow)
{
struct dp_refcnt *dp_refcnt;

HMAP_FOR_EACH_POP (dp_refcnt, key_node, &lflow->dp_refcnts_map) {
free(dp_refcnt);
}

hmap_destroy(&lflow->dp_refcnts_map);
}

static struct lflow_ref_node *
lflow_ref_node_find(struct hmap *lflow_ref_nodes, struct ovn_lflow *lflow,
uint32_t lflow_hash)
Expand Down

0 comments on commit 8c0f700

Please sign in to comment.