From de74023befa1876f64bc5871a2a4a51850517118 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 17 Feb 2022 21:13:05 +0000 Subject: netfs: Trace refcounting on the netfs_io_request struct Add refcount tracing for the netfs_io_request structure. Changes ======= ver #3) - Switch 'W=' to 'R=' in the traceline to match other request debug IDs. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622997668.3564931.14456171619219324968.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678200943.1200972.7241495532327787765.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692900920.2099075.11847712419940675791.stgit@warthog.procyon.org.uk/ # v3 --- fs/netfs/internal.h | 11 +++++++++-- fs/netfs/objects.c | 24 +++++++++++++++++------- fs/netfs/read_helper.c | 14 +++++++------- 3 files changed, 33 insertions(+), 16 deletions(-) (limited to 'fs/netfs') diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h index cf7a3ddb16a4..89b02357500d 100644 --- a/fs/netfs/internal.h +++ b/fs/netfs/internal.h @@ -20,13 +20,20 @@ struct netfs_io_request *netfs_alloc_request(const struct netfs_request_ops *ops, void *netfs_priv, struct file *file); -void netfs_get_request(struct netfs_io_request *rreq); +void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what); void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async); -void netfs_put_request(struct netfs_io_request *rreq, bool was_async); +void netfs_put_request(struct netfs_io_request *rreq, bool was_async, + enum netfs_rreq_ref_trace what); struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq); void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async); void netfs_get_subrequest(struct netfs_io_subrequest *subreq); +static inline void netfs_see_request(struct netfs_io_request *rreq, + enum netfs_rreq_ref_trace what) +{ + trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what); +} + /* * read_helper.c */ diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c index f7383c28dc6e..4e29c3bb6e5a 100644 --- a/fs/netfs/objects.c +++ b/fs/netfs/objects.c @@ -27,7 +27,7 @@ struct netfs_io_request *netfs_alloc_request( rreq->debug_id = atomic_inc_return(&debug_ids); INIT_LIST_HEAD(&rreq->subrequests); INIT_WORK(&rreq->work, netfs_rreq_work); - refcount_set(&rreq->usage, 1); + refcount_set(&rreq->ref, 1); __set_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags); if (ops->init_request) ops->init_request(rreq, file); @@ -37,9 +37,12 @@ struct netfs_io_request *netfs_alloc_request( return rreq; } -void netfs_get_request(struct netfs_io_request *rreq) +void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what) { - refcount_inc(&rreq->usage); + int r; + + __refcount_inc(&rreq->ref, &r); + trace_netfs_rreq_ref(rreq->debug_id, r + 1, what); } void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async) @@ -68,9 +71,16 @@ static void netfs_free_request(struct work_struct *work) netfs_stat_d(&netfs_n_rh_rreq); } -void netfs_put_request(struct netfs_io_request *rreq, bool was_async) +void netfs_put_request(struct netfs_io_request *rreq, bool was_async, + enum netfs_rreq_ref_trace what) { - if (refcount_dec_and_test(&rreq->usage)) { + unsigned int debug_id = rreq->debug_id; + bool dead; + int r; + + dead = __refcount_dec_and_test(&rreq->ref, &r); + trace_netfs_rreq_ref(debug_id, r - 1, what); + if (dead) { if (was_async) { rreq->work.func = netfs_free_request; if (!queue_work(system_unbound_wq, &rreq->work)) @@ -93,7 +103,7 @@ struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq INIT_LIST_HEAD(&subreq->rreq_link); refcount_set(&subreq->usage, 2); subreq->rreq = rreq; - netfs_get_request(rreq); + netfs_get_request(rreq, netfs_rreq_trace_get_subreq); netfs_stat(&netfs_n_rh_sreq); } @@ -113,7 +123,7 @@ static void __netfs_put_subrequest(struct netfs_io_subrequest *subreq, trace_netfs_sreq(subreq, netfs_sreq_trace_free); kfree(subreq); netfs_stat_d(&netfs_n_rh_sreq); - netfs_put_request(rreq, was_async); + netfs_put_request(rreq, was_async, netfs_rreq_trace_put_subreq); } void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async) diff --git a/fs/netfs/read_helper.c b/fs/netfs/read_helper.c index 181aeda32649..620c3be5ec0a 100644 --- a/fs/netfs/read_helper.c +++ b/fs/netfs/read_helper.c @@ -109,7 +109,7 @@ static void netfs_rreq_completed(struct netfs_io_request *rreq, bool was_async) { trace_netfs_rreq(rreq, netfs_rreq_trace_done); netfs_clear_subrequests(rreq, was_async); - netfs_put_request(rreq, was_async); + netfs_put_request(rreq, was_async, netfs_rreq_trace_put_complete); } /* @@ -799,7 +799,7 @@ void netfs_readahead(struct readahead_control *ractl, return; cleanup_free: - netfs_put_request(rreq, false); + netfs_put_request(rreq, false, netfs_rreq_trace_put_failed); return; cleanup: if (netfs_priv) @@ -858,7 +858,7 @@ int netfs_readpage(struct file *file, netfs_stat(&netfs_n_rh_readpage); trace_netfs_read(rreq, rreq->start, rreq->len, netfs_read_trace_readpage); - netfs_get_request(rreq); + netfs_get_request(rreq, netfs_rreq_trace_get_hold); atomic_set(&rreq->nr_outstanding, 1); do { @@ -883,7 +883,7 @@ int netfs_readpage(struct file *file, ret = -EIO; } out: - netfs_put_request(rreq, false); + netfs_put_request(rreq, false, netfs_rreq_trace_put_hold); return ret; } EXPORT_SYMBOL(netfs_readpage); @@ -1030,13 +1030,13 @@ retry: */ ractl._nr_pages = folio_nr_pages(folio); netfs_rreq_expand(rreq, &ractl); - netfs_get_request(rreq); /* We hold the folio locks, so we can drop the references */ folio_get(folio); while (readahead_folio(&ractl)) ; + netfs_get_request(rreq, netfs_rreq_trace_get_hold); atomic_set(&rreq->nr_outstanding, 1); do { if (!netfs_rreq_submit_slice(rreq, &debug_index)) @@ -1062,7 +1062,7 @@ retry: trace_netfs_failure(rreq, NULL, ret, netfs_fail_short_write_begin); ret = -EIO; } - netfs_put_request(rreq, false); + netfs_put_request(rreq, false, netfs_rreq_trace_put_hold); if (ret < 0) goto error; @@ -1078,7 +1078,7 @@ have_folio_no_wait: return 0; error_put: - netfs_put_request(rreq, false); + netfs_put_request(rreq, false, netfs_rreq_trace_put_failed); error: folio_unlock(folio); folio_put(folio); -- cgit v1.2.3