Improve the tracing of afs_volume objects to include displaying a debug ID so that different instances of volumes with the same "vid" can be distinguished. Also be consistent about displaying the volume's refcount (and not the cell's). Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: Marc Dionne <marc.dionne@xxxxxxxxxxxx> cc: linux-afs@xxxxxxxxxxxxxxxxxxx cc: linux-fsdevel@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20250224234154.2014840-9-dhowells@xxxxxxxxxx/ # v1 --- fs/afs/internal.h | 1 + fs/afs/volume.c | 15 +++++++++------ include/trace/events/afs.h | 18 +++++++++++------- 3 files changed, 21 insertions(+), 13 deletions(-) diff --git a/fs/afs/internal.h b/fs/afs/internal.h index 47e98a78f59f..97045e2a455d 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -623,6 +623,7 @@ struct afs_volume { afs_volid_t vid; /* The volume ID of this volume */ afs_volid_t vids[AFS_MAXTYPES]; /* All associated volume IDs */ refcount_t ref; + unsigned int debug_id; /* Debugging ID for traces */ time64_t update_at; /* Time at which to next update */ struct afs_cell *cell; /* Cell to which belongs (pins ref) */ struct rb_node cell_node; /* Link in cell->volumes */ diff --git a/fs/afs/volume.c b/fs/afs/volume.c index af3a3f57c1b3..0efff3d25133 100644 --- a/fs/afs/volume.c +++ b/fs/afs/volume.c @@ -10,6 +10,7 @@ #include "internal.h" static unsigned __read_mostly afs_volume_record_life = 60 * 60; +static atomic_t afs_volume_debug_id; static void afs_destroy_volume(struct work_struct *work); @@ -59,7 +60,7 @@ static void afs_remove_volume_from_cell(struct afs_volume *volume) struct afs_cell *cell = volume->cell; if (!hlist_unhashed(&volume->proc_link)) { - trace_afs_volume(volume->vid, refcount_read(&cell->ref), + trace_afs_volume(volume->debug_id, volume->vid, refcount_read(&volume->ref), afs_volume_trace_remove); write_seqlock(&cell->volume_lock); hlist_del_rcu(&volume->proc_link); @@ -84,6 +85,7 @@ static struct afs_volume *afs_alloc_volume(struct afs_fs_context *params, if (!volume) goto error_0; + volume->debug_id = atomic_inc_return(&afs_volume_debug_id); volume->vid = vldb->vid[params->type]; volume->update_at = ktime_get_real_seconds() + afs_volume_record_life; volume->cell = afs_get_cell(params->cell, afs_cell_trace_get_vol); @@ -115,7 +117,7 @@ static struct afs_volume *afs_alloc_volume(struct afs_fs_context *params, *_slist = slist; rcu_assign_pointer(volume->servers, slist); - trace_afs_volume(volume->vid, 1, afs_volume_trace_alloc); + trace_afs_volume(volume->debug_id, volume->vid, 1, afs_volume_trace_alloc); return volume; error_1: @@ -247,7 +249,7 @@ static void afs_destroy_volume(struct work_struct *work) afs_remove_volume_from_cell(volume); afs_put_serverlist(volume->cell->net, slist); afs_put_cell(volume->cell, afs_cell_trace_put_vol); - trace_afs_volume(volume->vid, refcount_read(&volume->ref), + trace_afs_volume(volume->debug_id, volume->vid, refcount_read(&volume->ref), afs_volume_trace_free); kfree_rcu(volume, rcu); @@ -262,7 +264,7 @@ bool afs_try_get_volume(struct afs_volume *volume, enum afs_volume_trace reason) int r; if (__refcount_inc_not_zero(&volume->ref, &r)) { - trace_afs_volume(volume->vid, r + 1, reason); + trace_afs_volume(volume->debug_id, volume->vid, r + 1, reason); return true; } return false; @@ -278,7 +280,7 @@ struct afs_volume *afs_get_volume(struct afs_volume *volume, int r; __refcount_inc(&volume->ref, &r); - trace_afs_volume(volume->vid, r + 1, reason); + trace_afs_volume(volume->debug_id, volume->vid, r + 1, reason); } return volume; } @@ -290,12 +292,13 @@ struct afs_volume *afs_get_volume(struct afs_volume *volume, void afs_put_volume(struct afs_volume *volume, enum afs_volume_trace reason) { if (volume) { + unsigned int debug_id = volume->debug_id; afs_volid_t vid = volume->vid; bool zero; int r; zero = __refcount_dec_and_test(&volume->ref, &r); - trace_afs_volume(vid, r - 1, reason); + trace_afs_volume(debug_id, vid, r - 1, reason); if (zero) schedule_work(&volume->destructor); } diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h index c19132605f41..cf94bf1e8286 100644 --- a/include/trace/events/afs.h +++ b/include/trace/events/afs.h @@ -1539,25 +1539,29 @@ TRACE_EVENT(afs_server, ); TRACE_EVENT(afs_volume, - TP_PROTO(afs_volid_t vid, int ref, enum afs_volume_trace reason), + TP_PROTO(unsigned int debug_id, afs_volid_t vid, int ref, + enum afs_volume_trace reason), - TP_ARGS(vid, ref, reason), + TP_ARGS(debug_id, vid, ref, reason), TP_STRUCT__entry( + __field(unsigned int, debug_id) __field(afs_volid_t, vid) __field(int, ref) __field(enum afs_volume_trace, reason) ), TP_fast_assign( - __entry->vid = vid; - __entry->ref = ref; - __entry->reason = reason; + __entry->debug_id = debug_id; + __entry->vid = vid; + __entry->ref = ref; + __entry->reason = reason; ), - TP_printk("V=%llx %s ur=%d", - __entry->vid, + TP_printk("V=%08x %s vid=%llx r=%d", + __entry->debug_id, __print_symbolic(__entry->reason, afs_volume_traces), + __entry->vid, __entry->ref) );
