Date: Mon, 5 Jul 2021 11:33:56 GMT From: Mateusz Guzik <mjg@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: git: d5fe617b09b2 - stable/13 - pfctl: cache getprotobynumber results Message-ID: <202107051133.165BXut8018157@gitrepo.freebsd.org>
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The branch stable/13 has been updated by mjg: URL: https://cgit.FreeBSD.org/src/commit/?id=d5fe617b09b2988676dcc0e323b6a88fd821fd41 commit d5fe617b09b2988676dcc0e323b6a88fd821fd41 Author: Mateusz Guzik <mjg@FreeBSD.org> AuthorDate: 2021-07-01 19:25:43 +0000 Commit: Mateusz Guzik <mjg@FreeBSD.org> CommitDate: 2021-07-05 11:32:14 +0000 pfctl: cache getprotobynumber results As for example pfctl -ss keeps calling it, it saves a lot of overhead from elided parsing of /etc/nsswitch.conf and /etc/protocols. Sample result when running a pre-nvlist binary with nfs root and dumping 7 mln states: before: 24.817u 62.993s 1:28.52 99.1% after: 8.064u 1.117s 0:18.87 48.5% Idea by Jim Thompson Reviewed by: kp Sponsored by: Rubicon Communications, LLC ("Netgate") (cherry picked from commit 858937bea4599d254a97ee6321683f8629604e15) --- sbin/pfctl/parse.y | 8 ++++---- sbin/pfctl/pf_print_state.c | 6 +++--- sbin/pfctl/pfctl.c | 43 +++++++++++++++++++++++++++++++++++++++++++ sbin/pfctl/pfctl.h | 2 ++ sbin/pfctl/pfctl_parser.c | 6 +++--- 5 files changed, 55 insertions(+), 10 deletions(-) diff --git a/sbin/pfctl/parse.y b/sbin/pfctl/parse.y index 4448a8255ce1..acd90e280b53 100644 --- a/sbin/pfctl/parse.y +++ b/sbin/pfctl/parse.y @@ -5017,13 +5017,13 @@ expand_label_port(const char *name, char *label, size_t len, void expand_label_proto(const char *name, char *label, size_t len, u_int8_t proto) { - struct protoent *pe; + const char *protoname; char n[4]; if (strstr(label, name) != NULL) { - pe = getprotobynumber(proto); - if (pe != NULL) - expand_label_str(label, len, name, pe->p_name); + protoname = pfctl_proto2name(proto); + if (protoname != NULL) + expand_label_str(label, len, name, protoname); else { snprintf(n, sizeof(n), "%u", proto); expand_label_str(label, len, name, n); diff --git a/sbin/pfctl/pf_print_state.c b/sbin/pfctl/pf_print_state.c index b1f0079154cf..b66a296d6080 100644 --- a/sbin/pfctl/pf_print_state.c +++ b/sbin/pfctl/pf_print_state.c @@ -211,7 +211,7 @@ print_state(struct pfctl_state *s, int opts) { struct pfctl_state_peer *src, *dst; struct pfctl_state_key *key, *sk, *nk; - struct protoent *p; + const char *protoname; int min, sec; sa_family_t af; uint8_t proto; @@ -243,8 +243,8 @@ print_state(struct pfctl_state *s, int opts) sk->port[1] = nk->port[1]; } printf("%s ", s->ifname); - if ((p = getprotobynumber(proto)) != NULL) - printf("%s ", p->p_name); + if ((protoname = pfctl_proto2name(proto)) != NULL) + printf("%s ", protoname); else printf("%u ", proto); diff --git a/sbin/pfctl/pfctl.c b/sbin/pfctl/pfctl.c index f82d75198d61..14b7f3a01657 100644 --- a/sbin/pfctl/pfctl.c +++ b/sbin/pfctl/pfctl.c @@ -254,6 +254,49 @@ usage(void) exit(1); } +/* + * Cache protocol number to name translations. + * + * Translation is performed a lot e.g., when dumping states and + * getprotobynumber is incredibly expensive. + * + * Note from the getprotobynumber(3) manpage: + * <quote> + * These functions use a thread-specific data space; if the data is needed + * for future use, it should be copied before any subsequent calls overwrite + * it. Only the Internet protocols are currently understood. + * </quote> + * + * Consequently we only cache the name and strdup it for safety. + * + * At the time of writing this comment the last entry in /etc/protocols is: + * divert 258 DIVERT # Divert pseudo-protocol [non IANA] + */ +const char * +pfctl_proto2name(int proto) +{ + static const char *pfctl_proto_cache[259]; + struct protoent *p; + + if (proto >= nitems(pfctl_proto_cache)) { + p = getprotobynumber(proto); + if (p == NULL) { + return (NULL); + } + return (p->p_name); + } + + if (pfctl_proto_cache[proto] == NULL) { + p = getprotobynumber(proto); + if (p == NULL) { + return (NULL); + } + pfctl_proto_cache[proto] = strdup(p->p_name); + } + + return (pfctl_proto_cache[proto]); +} + int pfctl_enable(int dev, int opts) { diff --git a/sbin/pfctl/pfctl.h b/sbin/pfctl/pfctl.h index f8ff5012e01b..80ef184fa90f 100644 --- a/sbin/pfctl/pfctl.h +++ b/sbin/pfctl/pfctl.h @@ -138,4 +138,6 @@ void pf_remove_if_empty_ruleset(struct pfctl_ruleset *); struct pfctl_ruleset *pf_find_ruleset(const char *); struct pfctl_ruleset *pf_find_or_create_ruleset(const char *); +const char *pfctl_proto2name(int); + #endif /* _PFCTL_H_ */ diff --git a/sbin/pfctl/pfctl_parser.c b/sbin/pfctl/pfctl_parser.c index ce460ab691ca..b4a1cde967bd 100644 --- a/sbin/pfctl/pfctl_parser.c +++ b/sbin/pfctl/pfctl_parser.c @@ -812,10 +812,10 @@ print_rule(struct pfctl_rule *r, const char *anchor_call, int verbose, int numer printf(" inet6"); } if (r->proto) { - struct protoent *p; + const char *protoname; - if ((p = getprotobynumber(r->proto)) != NULL) - printf(" proto %s", p->p_name); + if ((protoname = pfctl_proto2name(r->proto)) != NULL) + printf(" proto %s", protoname); else printf(" proto %u", r->proto); }
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