5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit 6939ace1f22681fface7841cdbf34d3204cc94b5 ]
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@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202310012359.YEw5IrK6-lkp@intel.com/ Cc: Amir Goldstein amir73il@gmail.com Reviewed-by: Jeff Layton jlayton@kernel.org Stable-dep-of: 4b14885411f7 ("nfsd: make all of the nfsd stats per-network namespace") [ cel: adjusted to apply to v5.15.y ] Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfsd/export.c | 32 +++++++++++++++++++++++--------- fs/nfsd/export.h | 4 ++-- fs/nfsd/stats.h | 12 ++++++------ 3 files changed, 31 insertions(+), 17 deletions(-)
--- a/fs/nfsd/export.c +++ b/fs/nfsd/export.c @@ -339,12 +339,16 @@ static int export_stats_init(struct expo
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 * 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); } @@ -744,13 +749,15 @@ static int svc_export_show(struct seq_fi 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); + struct percpu_counter *counter = exp->ex_stats->counter; + + 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(&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(&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(&counter[EXP_STATS_IO_WRITE])); seq_putc(m, '\n'); return 0; } @@ -796,7 +803,7 @@ static void svc_export_init(struct cache 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) @@ -832,7 +839,14 @@ static struct cache_head *svc_export_all 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; } --- 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; @@ -76,7 +76,7 @@ struct svc_export { struct nfsd4_deviceid_map *ex_devid_map; struct cache_detail *cd; struct rcu_head ex_rcu; - struct export_stats ex_stats; + struct export_stats *ex_stats; };
/* an "export key" (expkey) maps a filehandlefragement to an --- a/fs/nfsd/stats.h +++ b/fs/nfsd/stats.h @@ -60,22 +60,22 @@ static inline void nfsd_stats_rc_nocache 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)