On Mon, 2023-07-10 at 18:16 +0200, Lorenzo Bianconi wrote: > Introduce rpc_status entry in nfsd debug filesystem in order to dump > pending RPC requests debugging information. > > Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=366 > Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> > --- > Changes since RFCv1: > - riduce time holding nfsd_mutex bumping svc_serv refcoung in > nfsd_rpc_status_open() > - dump rqstp->rq_stime > - add missing kdoc for nfsd_rpc_status_open() > --- > fs/nfsd/nfs4proc.c | 4 +-- > fs/nfsd/nfsctl.c | 10 ++++++ > fs/nfsd/nfsd.h | 2 ++ > fs/nfsd/nfssvc.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++ > net/sunrpc/svc.c | 2 +- > 5 files changed, 102 insertions(+), 4 deletions(-) > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > index 5ae670807449..a4dd1ef104c3 100644 > --- a/fs/nfsd/nfs4proc.c > +++ b/fs/nfsd/nfs4proc.c > @@ -2452,8 +2452,6 @@ static inline void nfsd4_increment_op_stats(u32 opnum) > > static const struct nfsd4_operation nfsd4_ops[]; > > -static const char *nfsd4_op_name(unsigned opnum); > - > /* > * Enforce NFSv4.1 COMPOUND ordering rules: > * > @@ -3583,7 +3581,7 @@ void warn_on_nonidempotent_op(struct nfsd4_op *op) > } > } > > -static const char *nfsd4_op_name(unsigned opnum) > +const char *nfsd4_op_name(unsigned opnum) > { > if (opnum < ARRAY_SIZE(nfsd4_ops)) > return nfsd4_ops[opnum].op_name; > diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c > index 1b8b1aab9a15..629b4296e7c6 100644 > --- a/fs/nfsd/nfsctl.c > +++ b/fs/nfsd/nfsctl.c > @@ -57,6 +57,8 @@ enum { > NFSD_RecoveryDir, > NFSD_V4EndGrace, > #endif > + NFSD_Rpc_Status, > + > NFSD_MaxReserved > }; > > @@ -195,6 +197,13 @@ static inline struct net *netns(struct file *file) > return file_inode(file)->i_sb->s_fs_info; > } > > +static const struct file_operations nfsd_rpc_status_operations = { > + .open = nfsd_rpc_status_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = nfsd_pool_stats_release, > +}; > + > /* > * write_unlock_ip - Release all locks used by a client > * > @@ -1400,6 +1409,7 @@ static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc) > [NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR}, > [NFSD_V4EndGrace] = {"v4_end_grace", &transaction_ops, S_IWUSR|S_IRUGO}, > #endif > + [NFSD_Rpc_Status] = {"rpc_status", &nfsd_rpc_status_operations, S_IRUGO}, > /* last one */ {""} > }; > > diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > index d88498f8b275..75a3e1d55bc8 100644 > --- a/fs/nfsd/nfsd.h > +++ b/fs/nfsd/nfsd.h > @@ -94,6 +94,7 @@ int nfsd_get_nrthreads(int n, int *, struct net *); > int nfsd_set_nrthreads(int n, int *, struct net *); > int nfsd_pool_stats_open(struct inode *, struct file *); > int nfsd_pool_stats_release(struct inode *, struct file *); > +int nfsd_rpc_status_open(struct inode *inode, struct file *file); > void nfsd_shutdown_threads(struct net *net); > > void nfsd_put(struct net *net); > @@ -506,6 +507,7 @@ extern void nfsd4_ssc_init_umount_work(struct nfsd_net *nn); > > extern void nfsd4_init_leases_net(struct nfsd_net *nn); > > +const char *nfsd4_op_name(unsigned opnum); > #else /* CONFIG_NFSD_V4 */ > static inline int nfsd4_is_junction(struct dentry *dentry) > { > diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c > index 2154fa63c5f2..ef1eb8b1c5bf 100644 > --- a/fs/nfsd/nfssvc.c > +++ b/fs/nfsd/nfssvc.c > @@ -1147,3 +1147,91 @@ int nfsd_pool_stats_release(struct inode *inode, struct file *file) > mutex_unlock(&nfsd_mutex); > return ret; > } > + > +static int nfsd_rpc_status_show(struct seq_file *m, void *v) > +{ > + struct inode *inode = file_inode(m->file); > + struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); > + int i; > + > + rcu_read_lock(); > + Much nicer without all of the heavyweight locking, I think! > + for (i = 0; i < nn->nfsd_serv->sv_nrpools; i++) { > + struct svc_rqst *rqstp; > + > + seq_puts(m, "XID | FLAGS | PROG |"); > + seq_puts(m, " VERS | PROC\t| TS(us)\t |"); > + seq_puts(m, " REMOTE - LOCAL IP ADDR"); > + seq_puts(m, "\t\t\t\t\t\t\t\t | NFS4 COMPOUND OPS\n"); It may be best to just eliminate the header, or at the very least, only print it once by moving it outside of the for loop. > + list_for_each_entry_rcu(rqstp, > + &nn->nfsd_serv->sv_pools[i].sp_all_threads, > + rq_all) { > + if (!test_bit(RQ_BUSY, &rqstp->rq_flags)) > + continue; > + > + seq_printf(m, > + "0x%08x | 0x%08lx | 0x%08x | NFSv%d |" > + " %s\t| %016lld |", I'd definitely get rid of the '|' delimiters. I think that it'd be best to just separate the fields by single spaces, as that will be simpler for scripts to parse. There are plenty of examples in the kernel that do that (/proc/locks, /proc/self/mountstats, etc.). We can always write a simple shell or python script for nfs-utils that parses and pretty-prints the fields. > + be32_to_cpu(rqstp->rq_xid), rqstp->rq_flags, > + rqstp->rq_prog, rqstp->rq_vers, > + svc_proc_name(rqstp), > + ktime_to_us(rqstp->rq_stime)); > + > + if (rqstp->rq_addr.ss_family == AF_INET) { > + seq_printf(m, " %pI4 - %pI4\t\t\t\t\t\t\t |", > + &((struct sockaddr_in *)&rqstp->rq_addr)->sin_addr, > + &((struct sockaddr_in *)&rqstp->rq_daddr)->sin_addr); > + } else if (rqstp->rq_addr.ss_family == AF_INET6) { > + seq_printf(m, " %pI6 - %pI6 |", > + &((struct sockaddr_in6 *)&rqstp->rq_addr)->sin6_addr, > + &((struct sockaddr_in6 *)&rqstp->rq_daddr)->sin6_addr); > + } else { > + seq_printf(m, " Unknown address family: %hu\n", ...and if we're going to go for something machine-parseable, maybe just print this as "unknown:%hu". Also, I don't think you want the extra newline here. > + rqstp->rq_addr.ss_family); > + continue; > + } > +#ifdef CONFIG_NFSD_V4 > + if (rqstp->rq_vers == NFS4_VERSION && > + rqstp->rq_proc == NFSPROC4_COMPOUND) { > + /* NFSv4 compund */ > + struct nfsd4_compoundargs *args = rqstp->rq_argp; > + struct nfsd4_compoundres *resp = rqstp->rq_resp; > + > + while (resp->opcnt < args->opcnt) { > + struct nfsd4_op *op = &args->ops[resp->opcnt++]; > + > + seq_printf(m, " %s", nfsd4_op_name(op->opnum)); > + } > + } > +#endif /* CONFIG_NFSD_V4 */ > + seq_puts(m, "\n"); > + } > + } > + > + rcu_read_unlock(); > + > + return 0; > +} > + > +/** > + * nfsd_rpc_status_open - Atomically copy a write verifier > + * @inode: entry inode pointer. > + * @file: entry file pointer. > + * > + * This routine dumps pending RPC requests info queued into nfs server. > + */ > +int nfsd_rpc_status_open(struct inode *inode, struct file *file) > +{ > + struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); > + > + mutex_lock(&nfsd_mutex); > + if (!nn->nfsd_serv) { > + mutex_unlock(&nfsd_mutex); > + return -ENODEV; > + } > + > + svc_get(nn->nfsd_serv); > + mutex_unlock(&nfsd_mutex); > + > + return single_open(file, nfsd_rpc_status_show, inode->i_private); > +} > diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c > index 587811a002c9..44eac83b35a1 100644 > --- a/net/sunrpc/svc.c > +++ b/net/sunrpc/svc.c > @@ -1629,7 +1629,7 @@ const char *svc_proc_name(const struct svc_rqst *rqstp) > return rqstp->rq_procinfo->pc_name; > return "unknown"; > } > - > +EXPORT_SYMBOL_GPL(svc_proc_name); > > /** > * svc_encode_result_payload - mark a range of bytes as a result payload -- Jeff Layton <jlayton@xxxxxxxxxx>
