From 977e5f8ed0ab2786755f8d2a96b78a3c7320f7c4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 17 Apr 2020 17:31:26 +0100 Subject: afs: Split the usage count on struct afs_server Split the usage count on the afs_server struct to have an active count that registers who's actually using it separately from the reference count on the object. This allows a future patch to dispatch polling probes without advancing the "unuse" time into the future each time we emit a probe, which would otherwise prevent unused server records from expiring. Included in this: (1) The latter part of afs_destroy_server() in which the RCU destruction of afs_server objects is invoked and the outstanding server count is decremented is split out into __afs_put_server(). (2) afs_put_server() now calls __afs_put_server() rather then setting the management timer. (3) The calls begun by afs_fs_give_up_all_callbacks() and afs_fs_get_capabilities() can now take a ref on the server record, so afs_destroy_server() can just drop its ref and needn't wait for the completion of these calls. They'll put the ref when they're done. (4) Because of (3), afs_fs_probe_done() no longer needs to wake up afs_destroy_server() with server->probe_outstanding. (5) afs_gc_servers can be simplified. It only needs to check if server->active is 0 rather than playing games with the refcount. (6) afs_manage_servers() can propose a server for gc if usage == 0 rather than if ref == 1. The gc is effected by (5). Signed-off-by: David Howells --- include/trace/events/afs.h | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) (limited to 'include/trace') diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h index c612cabbc378..f9691f69b2d6 100644 --- a/include/trace/events/afs.h +++ b/include/trace/events/afs.h @@ -33,6 +33,7 @@ enum afs_server_trace { afs_server_trace_destroy, afs_server_trace_free, afs_server_trace_gc, + afs_server_trace_get_by_addr, afs_server_trace_get_by_uuid, afs_server_trace_get_caps, afs_server_trace_get_install, @@ -241,6 +242,7 @@ enum afs_cb_break_reason { EM(afs_server_trace_destroy, "DESTROY ") \ EM(afs_server_trace_free, "FREE ") \ EM(afs_server_trace_gc, "GC ") \ + EM(afs_server_trace_get_by_addr, "GET addr ") \ EM(afs_server_trace_get_by_uuid, "GET uuid ") \ EM(afs_server_trace_get_caps, "GET caps ") \ EM(afs_server_trace_get_install, "GET inst ") \ @@ -1271,26 +1273,30 @@ TRACE_EVENT(afs_cb_miss, ); TRACE_EVENT(afs_server, - TP_PROTO(struct afs_server *server, int usage, enum afs_server_trace reason), + TP_PROTO(struct afs_server *server, int ref, int active, + enum afs_server_trace reason), - TP_ARGS(server, usage, reason), + TP_ARGS(server, ref, active, reason), TP_STRUCT__entry( __field(unsigned int, server ) - __field(int, usage ) + __field(int, ref ) + __field(int, active ) __field(int, reason ) ), TP_fast_assign( __entry->server = server->debug_id; - __entry->usage = usage; + __entry->ref = ref; + __entry->active = active; __entry->reason = reason; ), - TP_printk("s=%08x %s u=%d", + TP_printk("s=%08x %s u=%d a=%d", __entry->server, __print_symbolic(__entry->reason, afs_server_traces), - __entry->usage) + __entry->ref, + __entry->active) ); #endif /* _TRACE_AFS_H */ -- cgit v1.2.3-59-g8ed1b