From: Pavel Emelyanov Date: Thu, 24 Apr 2008 08:02:16 +0000 (-0700) Subject: [NET]: Fix heavy stack usage in seq_file output routines. X-Git-Tag: v2.6.26-rc1~1088^2~1 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5e659e4cb0eedacdc1f621a61e400a4611ddef8a;p=linux-2.6 [NET]: Fix heavy stack usage in seq_file output routines. Plan C: we can follow the Al Viro's proposal about %n like in this patch. The same applies to udp, fib (the /proc/net/route file), rt_cache and sctp debug. This is minus ~150-200 bytes for each. Signed-off-by: Pavel Emelyanov Signed-off-by: David S. Miller --- diff --git a/net/ipv4/fib_hash.c b/net/ipv4/fib_hash.c index 02088deb04..2e2fc3376a 100644 --- a/net/ipv4/fib_hash.c +++ b/net/ipv4/fib_hash.c @@ -1003,7 +1003,7 @@ static unsigned fib_flag_trans(int type, __be32 mask, struct fib_info *fi) static int fib_seq_show(struct seq_file *seq, void *v) { struct fib_iter_state *iter; - char bf[128]; + int len; __be32 prefix, mask; unsigned flags; struct fib_node *f; @@ -1025,18 +1025,19 @@ static int fib_seq_show(struct seq_file *seq, void *v) mask = FZ_MASK(iter->zone); flags = fib_flag_trans(fa->fa_type, mask, fi); if (fi) - snprintf(bf, sizeof(bf), - "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u", + seq_printf(seq, + "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u%n", fi->fib_dev ? fi->fib_dev->name : "*", prefix, fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority, mask, (fi->fib_advmss ? fi->fib_advmss + 40 : 0), fi->fib_window, - fi->fib_rtt >> 3); + fi->fib_rtt >> 3, &len); else - snprintf(bf, sizeof(bf), - "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u", - prefix, 0, flags, 0, 0, 0, mask, 0, 0, 0); - seq_printf(seq, "%-127s\n", bf); + seq_printf(seq, + "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u%n", + prefix, 0, flags, 0, 0, 0, mask, 0, 0, 0, &len); + + seq_printf(seq, "%*s\n", 127 - len, ""); out: return 0; } diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index ea294fffb9..4b02d14e7a 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -2602,15 +2602,16 @@ static int fib_route_seq_show(struct seq_file *seq, void *v) list_for_each_entry_rcu(fa, &li->falh, fa_list) { const struct fib_info *fi = fa->fa_info; unsigned flags = fib_flag_trans(fa->fa_type, mask, fi); - char bf[128]; + int len; if (fa->fa_type == RTN_BROADCAST || fa->fa_type == RTN_MULTICAST) continue; if (fi) - snprintf(bf, sizeof(bf), - "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u", + seq_printf(seq, + "%s\t%08X\t%08X\t%04X\t%d\t%u\t" + "%d\t%08X\t%d\t%u\t%u%n", fi->fib_dev ? fi->fib_dev->name : "*", prefix, fi->fib_nh->nh_gw, flags, 0, 0, @@ -2619,14 +2620,15 @@ static int fib_route_seq_show(struct seq_file *seq, void *v) (fi->fib_advmss ? fi->fib_advmss + 40 : 0), fi->fib_window, - fi->fib_rtt >> 3); + fi->fib_rtt >> 3, &len); else - snprintf(bf, sizeof(bf), - "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u", + seq_printf(seq, + "*\t%08X\t%08X\t%04X\t%d\t%u\t" + "%d\t%08X\t%d\t%u\t%u%n", prefix, 0, flags, 0, 0, 0, - mask, 0, 0, 0); + mask, 0, 0, 0, &len); - seq_printf(seq, "%-127s\n", bf); + seq_printf(seq, "%*s\n", 127 - len, ""); } } diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 780e9484c8..ce25a13f34 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -367,10 +367,10 @@ static int rt_cache_seq_show(struct seq_file *seq, void *v) "HHUptod\tSpecDst"); else { struct rtable *r = v; - char temp[256]; + int len; - sprintf(temp, "%s\t%08lX\t%08lX\t%8X\t%d\t%u\t%d\t" - "%08lX\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X", + seq_printf(seq, "%s\t%08lX\t%08lX\t%8X\t%d\t%u\t%d\t" + "%08lX\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n", r->u.dst.dev ? r->u.dst.dev->name : "*", (unsigned long)r->rt_dst, (unsigned long)r->rt_gateway, r->rt_flags, atomic_read(&r->u.dst.__refcnt), @@ -384,8 +384,9 @@ static int rt_cache_seq_show(struct seq_file *seq, void *v) r->u.dst.hh ? atomic_read(&r->u.dst.hh->hh_refcnt) : -1, r->u.dst.hh ? (r->u.dst.hh->hh_output == dev_queue_xmit) : 0, - r->rt_spec_dst); - seq_printf(seq, "%-127s\n", temp); + r->rt_spec_dst, &len); + + seq_printf(seq, "%*s\n", 127 - len, ""); } return 0; } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 776615180b..0e9bc12070 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2255,13 +2255,13 @@ void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) } static void get_openreq4(struct sock *sk, struct request_sock *req, - char *tmpbuf, int i, int uid) + struct seq_file *f, int i, int uid, int *len) { const struct inet_request_sock *ireq = inet_rsk(req); int ttd = req->expires - jiffies; - sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" - " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %p", + seq_printf(f, "%4d: %08X:%04X %08X:%04X" + " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %p%n", i, ireq->loc_addr, ntohs(inet_sk(sk)->sport), @@ -2276,10 +2276,11 @@ static void get_openreq4(struct sock *sk, struct request_sock *req, 0, /* non standard timer */ 0, /* open_requests have no inode */ atomic_read(&sk->sk_refcnt), - req); + req, + len); } -static void get_tcp4_sock(struct sock *sk, char *tmpbuf, int i) +static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) { int timer_active; unsigned long timer_expires; @@ -2305,8 +2306,8 @@ static void get_tcp4_sock(struct sock *sk, char *tmpbuf, int i) timer_expires = jiffies; } - sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " - "%08X %5d %8d %lu %d %p %u %u %u %u %d", + seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " + "%08X %5d %8d %lu %d %p %u %u %u %u %d%n", i, src, srcp, dest, destp, sk->sk_state, tp->write_seq - tp->snd_una, sk->sk_state == TCP_LISTEN ? sk->sk_ack_backlog : @@ -2322,11 +2323,12 @@ static void get_tcp4_sock(struct sock *sk, char *tmpbuf, int i) icsk->icsk_ack.ato, (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, tp->snd_cwnd, - tp->snd_ssthresh >= 0xFFFF ? -1 : tp->snd_ssthresh); + tp->snd_ssthresh >= 0xFFFF ? -1 : tp->snd_ssthresh, + len); } static void get_timewait4_sock(struct inet_timewait_sock *tw, - char *tmpbuf, int i) + struct seq_file *f, int i, int *len) { __be32 dest, src; __u16 destp, srcp; @@ -2340,11 +2342,11 @@ static void get_timewait4_sock(struct inet_timewait_sock *tw, destp = ntohs(tw->tw_dport); srcp = ntohs(tw->tw_sport); - sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" - " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p", + seq_printf(f, "%4d: %08X:%04X %08X:%04X" + " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p%n", i, src, srcp, dest, destp, tw->tw_substate, 0, 0, 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, - atomic_read(&tw->tw_refcnt), tw); + atomic_read(&tw->tw_refcnt), tw, len); } #define TMPSZ 150 @@ -2352,7 +2354,7 @@ static void get_timewait4_sock(struct inet_timewait_sock *tw, static int tcp4_seq_show(struct seq_file *seq, void *v) { struct tcp_iter_state* st; - char tmpbuf[TMPSZ + 1]; + int len; if (v == SEQ_START_TOKEN) { seq_printf(seq, "%-*s\n", TMPSZ - 1, @@ -2366,16 +2368,16 @@ static int tcp4_seq_show(struct seq_file *seq, void *v) switch (st->state) { case TCP_SEQ_STATE_LISTENING: case TCP_SEQ_STATE_ESTABLISHED: - get_tcp4_sock(v, tmpbuf, st->num); + get_tcp4_sock(v, seq, st->num, &len); break; case TCP_SEQ_STATE_OPENREQ: - get_openreq4(st->syn_wait_sk, v, tmpbuf, st->num, st->uid); + get_openreq4(st->syn_wait_sk, v, seq, st->num, st->uid, &len); break; case TCP_SEQ_STATE_TIME_WAIT: - get_timewait4_sock(v, tmpbuf, st->num); + get_timewait4_sock(v, seq, st->num, &len); break; } - seq_printf(seq, "%-*s\n", TMPSZ - 1, tmpbuf); + seq_printf(seq, "%*s\n", TMPSZ - 1 - len, ""); out: return 0; } diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index b053ac7952..1f535e3151 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1619,7 +1619,8 @@ void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo) } /* ------------------------------------------------------------------------ */ -static void udp4_format_sock(struct sock *sp, char *tmpbuf, int bucket) +static void udp4_format_sock(struct sock *sp, struct seq_file *f, + int bucket, int *len) { struct inet_sock *inet = inet_sk(sp); __be32 dest = inet->daddr; @@ -1627,13 +1628,13 @@ static void udp4_format_sock(struct sock *sp, char *tmpbuf, int bucket) __u16 destp = ntohs(inet->dport); __u16 srcp = ntohs(inet->sport); - sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" - " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p", + seq_printf(f, "%4d: %08X:%04X %08X:%04X" + " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p%n", bucket, src, srcp, dest, destp, sp->sk_state, atomic_read(&sp->sk_wmem_alloc), atomic_read(&sp->sk_rmem_alloc), 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), - atomic_read(&sp->sk_refcnt), sp); + atomic_read(&sp->sk_refcnt), sp, len); } int udp4_seq_show(struct seq_file *seq, void *v) @@ -1644,11 +1645,11 @@ int udp4_seq_show(struct seq_file *seq, void *v) "rx_queue tr tm->when retrnsmt uid timeout " "inode"); else { - char tmpbuf[129]; struct udp_iter_state *state = seq->private; + int len; - udp4_format_sock(v, tmpbuf, state->bucket); - seq_printf(seq, "%-127s\n", tmpbuf); + udp4_format_sock(v, seq, state->bucket, &len); + seq_printf(seq, "%*s\n", 127 - len ,""); } return 0; } diff --git a/net/sctp/objcnt.c b/net/sctp/objcnt.c index cfeb07ea1b..f73ec0ea93 100644 --- a/net/sctp/objcnt.c +++ b/net/sctp/objcnt.c @@ -83,13 +83,12 @@ static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = { */ static int sctp_objcnt_seq_show(struct seq_file *seq, void *v) { - int i; - char temp[128]; + int i, len; i = (int)*(loff_t *)v; - sprintf(temp, "%s: %d", sctp_dbg_objcnt[i].label, - atomic_read(sctp_dbg_objcnt[i].counter)); - seq_printf(seq, "%-127s\n", temp); + seq_printf(seq, "%s: %d%n", sctp_dbg_objcnt[i].label, + atomic_read(sctp_dbg_objcnt[i].counter), &len); + seq_printf(seq, "%*s\n", 127 - len, ""); return 0; }