From 6cd3d6fd1fe2feae5ff9f6a821081569bb140bf4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 17 Feb 2022 15:01:24 +0000 Subject: netfs: Trace refcounting on the netfs_io_subrequest struct Add refcount tracing for the netfs_io_subrequest 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/164622998584.3564931.5052255990645723639.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678202603.1200972.14726007419792315578.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692901860.2099075.4845820886851239935.stgit@warthog.procyon.org.uk/ # v3 --- fs/netfs/internal.h | 2 -- fs/netfs/objects.c | 32 +++++++++++++++++++++++--------- fs/netfs/read_helper.c | 20 +++++++++++--------- 3 files changed, 34 insertions(+), 20 deletions(-) (limited to 'fs/netfs') diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h index 89b02357500d..a0b7d1bf9f3d 100644 --- a/fs/netfs/internal.h +++ b/fs/netfs/internal.h @@ -25,8 +25,6 @@ void netfs_clear_subrequests(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) diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c index 4e29c3bb6e5a..39097893e847 100644 --- a/fs/netfs/objects.c +++ b/fs/netfs/objects.c @@ -53,7 +53,8 @@ void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async) subreq = list_first_entry(&rreq->subrequests, struct netfs_io_subrequest, rreq_link); list_del(&subreq->rreq_link); - netfs_put_subrequest(subreq, was_async); + netfs_put_subrequest(subreq, was_async, + netfs_sreq_trace_put_clear); } } @@ -101,7 +102,7 @@ struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq subreq = kzalloc(sizeof(struct netfs_io_subrequest), GFP_KERNEL); if (subreq) { INIT_LIST_HEAD(&subreq->rreq_link); - refcount_set(&subreq->usage, 2); + refcount_set(&subreq->ref, 2); subreq->rreq = rreq; netfs_get_request(rreq, netfs_rreq_trace_get_subreq); netfs_stat(&netfs_n_rh_sreq); @@ -110,13 +111,18 @@ struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq return subreq; } -void netfs_get_subrequest(struct netfs_io_subrequest *subreq) +void netfs_get_subrequest(struct netfs_io_subrequest *subreq, + enum netfs_sreq_ref_trace what) { - refcount_inc(&subreq->usage); + int r; + + __refcount_inc(&subreq->ref, &r); + trace_netfs_sreq_ref(subreq->rreq->debug_id, subreq->debug_index, r + 1, + what); } -static void __netfs_put_subrequest(struct netfs_io_subrequest *subreq, - bool was_async) +static void netfs_free_subrequest(struct netfs_io_subrequest *subreq, + bool was_async) { struct netfs_io_request *rreq = subreq->rreq; @@ -126,8 +132,16 @@ static void __netfs_put_subrequest(struct netfs_io_subrequest *subreq, netfs_put_request(rreq, was_async, netfs_rreq_trace_put_subreq); } -void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async) +void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async, + enum netfs_sreq_ref_trace what) { - if (refcount_dec_and_test(&subreq->usage)) - __netfs_put_subrequest(subreq, was_async); + unsigned int debug_index = subreq->debug_index; + unsigned int debug_id = subreq->rreq->debug_id; + bool dead; + int r; + + dead = __refcount_dec_and_test(&subreq->ref, &r); + trace_netfs_sreq_ref(debug_id, debug_index, r - 1, what); + if (dead) + netfs_free_subrequest(subreq, was_async); } diff --git a/fs/netfs/read_helper.c b/fs/netfs/read_helper.c index 620c3be5ec0a..8f277da487b6 100644 --- a/fs/netfs/read_helper.c +++ b/fs/netfs/read_helper.c @@ -167,7 +167,7 @@ static void netfs_rreq_copy_terminated(void *priv, ssize_t transferred_or_error, if (atomic_dec_and_test(&rreq->nr_copy_ops)) netfs_rreq_unmark_after_write(rreq, was_async); - netfs_put_subrequest(subreq, was_async); + netfs_put_subrequest(subreq, was_async, netfs_sreq_trace_put_terminated); } /* @@ -191,7 +191,8 @@ static void netfs_rreq_do_write_to_cache(struct netfs_io_request *rreq) list_for_each_entry_safe(subreq, p, &rreq->subrequests, rreq_link) { if (!test_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags)) { list_del_init(&subreq->rreq_link); - netfs_put_subrequest(subreq, false); + netfs_put_subrequest(subreq, false, + netfs_sreq_trace_put_no_copy); } } @@ -203,7 +204,8 @@ static void netfs_rreq_do_write_to_cache(struct netfs_io_request *rreq) break; subreq->len += next->len; list_del_init(&next->rreq_link); - netfs_put_subrequest(next, false); + netfs_put_subrequest(next, false, + netfs_sreq_trace_put_merged); } ret = cres->ops->prepare_write(cres, &subreq->start, &subreq->len, @@ -219,7 +221,7 @@ static void netfs_rreq_do_write_to_cache(struct netfs_io_request *rreq) atomic_inc(&rreq->nr_copy_ops); netfs_stat(&netfs_n_rh_write); - netfs_get_subrequest(subreq); + netfs_get_subrequest(subreq, netfs_sreq_trace_get_copy_to_cache); trace_netfs_sreq(subreq, netfs_sreq_trace_write); cres->ops->write(cres, subreq->start, &iter, netfs_rreq_copy_terminated, subreq); @@ -342,7 +344,7 @@ static void netfs_rreq_short_read(struct netfs_io_request *rreq, netfs_stat(&netfs_n_rh_short_read); trace_netfs_sreq(subreq, netfs_sreq_trace_resubmit_short); - netfs_get_subrequest(subreq); + netfs_get_subrequest(subreq, netfs_sreq_trace_get_short_read); atomic_inc(&rreq->nr_outstanding); if (subreq->source == NETFS_READ_FROM_CACHE) netfs_read_from_cache(rreq, subreq, NETFS_READ_HOLE_CLEAR); @@ -376,7 +378,7 @@ static bool netfs_rreq_perform_resubmissions(struct netfs_io_request *rreq) subreq->error = 0; netfs_stat(&netfs_n_rh_download_instead); trace_netfs_sreq(subreq, netfs_sreq_trace_download_instead); - netfs_get_subrequest(subreq); + netfs_get_subrequest(subreq, netfs_sreq_trace_get_resubmit); atomic_inc(&rreq->nr_outstanding); netfs_read_from_server(rreq, subreq); } else if (test_bit(NETFS_SREQ_SHORT_IO, &subreq->flags)) { @@ -538,7 +540,7 @@ out: else if (u == 1) wake_up_var(&rreq->nr_outstanding); - netfs_put_subrequest(subreq, was_async); + netfs_put_subrequest(subreq, was_async, netfs_sreq_trace_put_terminated); return; incomplete: @@ -683,7 +685,7 @@ static bool netfs_rreq_submit_slice(struct netfs_io_request *rreq, subreq_failed: rreq->error = subreq->error; - netfs_put_subrequest(subreq, false); + netfs_put_subrequest(subreq, false, netfs_sreq_trace_put_failed); return false; } @@ -1030,13 +1032,13 @@ retry: */ ractl._nr_pages = folio_nr_pages(folio); netfs_rreq_expand(rreq, &ractl); + netfs_get_request(rreq, netfs_rreq_trace_get_hold); /* 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)) -- cgit v1.2.3