On Sun, 2023-10-01 at 13:25 -0400, Chuck Lever wrote: > From: Chuck Lever <chuck.lever@xxxxxxxxxx> > > fs/nfsd/export.c: In function 'svc_export_parse': > fs/nfsd/export.c:737:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=] > 737 | } > > On my systems, svc_export_parse() has a stack frame of over 800 > bytes, not 1040, but nonetheless, it could do with some reduction. > > When a struct svc_export is on the stack, it's a temporary structure > used as an argument, and not visible as an actual exported FS. No > need to reserve space for export_stats in such cases. > > Reported-by: kernel test robot <lkp@xxxxxxxxx> > Closes: https://lore.kernel.org/oe-kbuild-all/202310012359.YEw5IrK6-lkp@xxxxxxxxx/ > Cc: Amir Goldstein <amir73il@xxxxxxxxx> > Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> > --- > fs/nfsd/export.c | 30 +++++++++++++++++++++--------- > fs/nfsd/export.h | 4 ++-- > fs/nfsd/stats.h | 12 ++++++------ > 3 files changed, 29 insertions(+), 17 deletions(-) > > diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c > index 11a0eaa2f914..7cf26bfe199d 100644 > --- a/fs/nfsd/export.c > +++ b/fs/nfsd/export.c > @@ -339,12 +339,16 @@ static int export_stats_init(struct export_stats *stats) > > static void export_stats_reset(struct export_stats *stats) > { > - nfsd_percpu_counters_reset(stats->counter, EXP_STATS_COUNTERS_NUM); > + if (stats) > + nfsd_percpu_counters_reset(stats->counter, > + EXP_STATS_COUNTERS_NUM); > } > > static void export_stats_destroy(struct export_stats *stats) > { > - nfsd_percpu_counters_destroy(stats->counter, EXP_STATS_COUNTERS_NUM); > + if (stats) > + nfsd_percpu_counters_destroy(stats->counter, > + EXP_STATS_COUNTERS_NUM); > } > > static void svc_export_put(struct kref *ref) > @@ -353,7 +357,8 @@ static void svc_export_put(struct kref *ref) > path_put(&exp->ex_path); > auth_domain_put(exp->ex_client); > nfsd4_fslocs_free(&exp->ex_fslocs); > - export_stats_destroy(&exp->ex_stats); > + export_stats_destroy(exp->ex_stats); > + kfree(exp->ex_stats); > kfree(exp->ex_uuid); > kfree_rcu(exp, ex_rcu); > } > @@ -767,13 +772,13 @@ static int svc_export_show(struct seq_file *m, > seq_putc(m, '\t'); > seq_escape(m, exp->ex_client->name, " \t\n\\"); > if (export_stats) { > - seq_printf(m, "\t%lld\n", exp->ex_stats.start_time); > + seq_printf(m, "\t%lld\n", exp->ex_stats->start_time); > seq_printf(m, "\tfh_stale: %lld\n", > - percpu_counter_sum_positive(&exp->ex_stats.counter[EXP_STATS_FH_STALE])); > + percpu_counter_sum_positive(&exp->ex_stats->counter[EXP_STATS_FH_STALE])); > seq_printf(m, "\tio_read: %lld\n", > - percpu_counter_sum_positive(&exp->ex_stats.counter[EXP_STATS_IO_READ])); > + percpu_counter_sum_positive(&exp->ex_stats->counter[EXP_STATS_IO_READ])); > seq_printf(m, "\tio_write: %lld\n", > - percpu_counter_sum_positive(&exp->ex_stats.counter[EXP_STATS_IO_WRITE])); > + percpu_counter_sum_positive(&exp->ex_stats->counter[EXP_STATS_IO_WRITE])); > seq_putc(m, '\n'); > return 0; > } > @@ -819,7 +824,7 @@ static void svc_export_init(struct cache_head *cnew, struct cache_head *citem) > new->ex_layout_types = 0; > new->ex_uuid = NULL; > new->cd = item->cd; > - export_stats_reset(&new->ex_stats); > + export_stats_reset(new->ex_stats); > } > > static void export_update(struct cache_head *cnew, struct cache_head *citem) > @@ -856,7 +861,14 @@ static struct cache_head *svc_export_alloc(void) > if (!i) > return NULL; > > - if (export_stats_init(&i->ex_stats)) { > + i->ex_stats = kmalloc(sizeof(i->ex_stats), GFP_KERNEL); > + if (!i->ex_stats) { > + kfree(i); > + return NULL; > + } > + > + if (export_stats_init(i->ex_stats)) { > + kfree(i->ex_stats); > kfree(i); > return NULL; > } > diff --git a/fs/nfsd/export.h b/fs/nfsd/export.h > index 2df8ae25aad3..ca9dc230ae3d 100644 > --- a/fs/nfsd/export.h > +++ b/fs/nfsd/export.h > @@ -64,10 +64,10 @@ struct svc_export { > struct cache_head h; > struct auth_domain * ex_client; > int ex_flags; > + int ex_fsid; > struct path ex_path; > kuid_t ex_anon_uid; > kgid_t ex_anon_gid; > - int ex_fsid; > unsigned char * ex_uuid; /* 16 byte fsid */ > struct nfsd4_fs_locations ex_fslocs; > uint32_t ex_nflavors; > @@ -76,8 +76,8 @@ struct svc_export { > struct nfsd4_deviceid_map *ex_devid_map; > struct cache_detail *cd; > struct rcu_head ex_rcu; > - struct export_stats ex_stats; > unsigned long ex_xprtsec_modes; > + struct export_stats *ex_stats; > }; > > /* an "export key" (expkey) maps a filehandlefragement to an > diff --git a/fs/nfsd/stats.h b/fs/nfsd/stats.h > index a3e9e2f47ec4..14f50c660b61 100644 > --- a/fs/nfsd/stats.h > +++ b/fs/nfsd/stats.h > @@ -61,22 +61,22 @@ static inline void nfsd_stats_rc_nocache_inc(void) > static inline void nfsd_stats_fh_stale_inc(struct svc_export *exp) > { > percpu_counter_inc(&nfsdstats.counter[NFSD_STATS_FH_STALE]); > - if (exp) > - percpu_counter_inc(&exp->ex_stats.counter[EXP_STATS_FH_STALE]); > + if (exp && exp->ex_stats) > + percpu_counter_inc(&exp->ex_stats->counter[EXP_STATS_FH_STALE]); > } > > static inline void nfsd_stats_io_read_add(struct svc_export *exp, s64 amount) > { > percpu_counter_add(&nfsdstats.counter[NFSD_STATS_IO_READ], amount); > - if (exp) > - percpu_counter_add(&exp->ex_stats.counter[EXP_STATS_IO_READ], amount); > + if (exp && exp->ex_stats) > + percpu_counter_add(&exp->ex_stats->counter[EXP_STATS_IO_READ], amount); > } > > static inline void nfsd_stats_io_write_add(struct svc_export *exp, s64 amount) > { > percpu_counter_add(&nfsdstats.counter[NFSD_STATS_IO_WRITE], amount); > - if (exp) > - percpu_counter_add(&exp->ex_stats.counter[EXP_STATS_IO_WRITE], amount); > + if (exp && exp->ex_stats) > + percpu_counter_add(&exp->ex_stats->counter[EXP_STATS_IO_WRITE], amount); > } > > static inline void nfsd_stats_payload_misses_inc(struct nfsd_net *nn) > > Seems reasonable. Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>