diff options
Diffstat (limited to 'system/xen/xsa/xsa206-4.8-0014-oxenstored-don-t-wake-to-issue-no-conflict-credit.patch')
| -rw-r--r-- | system/xen/xsa/xsa206-4.8-0014-oxenstored-don-t-wake-to-issue-no-conflict-credit.patch | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/system/xen/xsa/xsa206-4.8-0014-oxenstored-don-t-wake-to-issue-no-conflict-credit.patch b/system/xen/xsa/xsa206-4.8-0014-oxenstored-don-t-wake-to-issue-no-conflict-credit.patch deleted file mode 100644 index 8aae281406..0000000000 --- a/system/xen/xsa/xsa206-4.8-0014-oxenstored-don-t-wake-to-issue-no-conflict-credit.patch +++ /dev/null @@ -1,141 +0,0 @@ -From 374c6a67e3d139a04ecde127a63ce70d24ed7b45 Mon Sep 17 00:00:00 2001 -From: Thomas Sanders <thomas.sanders@citrix.com> -Date: Fri, 24 Mar 2017 19:55:03 +0000 -Subject: [PATCH 14/15] oxenstored: don't wake to issue no conflict-credit - -In the main loop, when choosing the timeout for the select function -call, we were setting it so as to wake up to issue conflict-credit to -any domains that could accept it. When xenstore is idle, this would -mean waking up every 50ms (by default) to do no work. With this -commit, we check whether any domain is below its cap, and if not then -we set the timeout for longer (the same timeout as before the -conflict-protection feature was added). - -Reported-by: Juergen Gross <jgross@suse.com> -Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com> -Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com> ---- - tools/ocaml/xenstored/domains.ml | 51 ++++++++++++++++++++++++++++++-------- - tools/ocaml/xenstored/xenstored.ml | 5 +++- - 2 files changed, 44 insertions(+), 12 deletions(-) - -diff --git a/tools/ocaml/xenstored/domains.ml b/tools/ocaml/xenstored/domains.ml -index 99f68c7..61d1e2e 100644 ---- a/tools/ocaml/xenstored/domains.ml -+++ b/tools/ocaml/xenstored/domains.ml -@@ -35,8 +35,9 @@ type domains = { - on_first_conflict_pause: unit -> unit; - - (* If config is set to use individual instead of aggregate conflict-rate-limiting, -- we use this instead of the queues. *) -- mutable n_paused: int; -+ we use these counts instead of the queues. The second one includes the first. *) -+ mutable n_paused: int; (* Number of domains with zero or negative credit *) -+ mutable n_penalised: int; (* Number of domains with less than maximum credit *) - } - - let init eventchn on_first_conflict_pause = { -@@ -46,6 +47,7 @@ let init eventchn on_first_conflict_pause = { - doms_with_conflict_penalty = Queue.create (); - on_first_conflict_pause = on_first_conflict_pause; - n_paused = 0; -+ n_penalised = 0; - } - let del doms id = Hashtbl.remove doms.table id - let exist doms id = Hashtbl.mem doms.table id -@@ -53,6 +55,23 @@ let find doms id = Hashtbl.find doms.table id - let number doms = Hashtbl.length doms.table - let iter doms fct = Hashtbl.iter (fun _ b -> fct b) doms.table - -+let rec is_empty_queue q = -+ Queue.is_empty q || -+ if !(Queue.peek q) = None -+ then ( -+ ignore (Queue.pop q); -+ is_empty_queue q -+ ) else false -+ -+let all_at_max_credit doms = -+ if !Define.conflict_rate_limit_is_aggregate -+ then -+ (* Check both becuase if burst limit is 1.0 then a domain can go straight -+ * from max-credit to paused without getting into the penalty queue. *) -+ is_empty_queue doms.doms_with_conflict_penalty -+ && is_empty_queue doms.doms_conflict_paused -+ else doms.n_penalised = 0 -+ - (* Functions to handle queues of domains given that the domain might be deleted while in a queue. *) - let push dom queue = - Queue.push (ref (Some dom)) queue -@@ -130,13 +149,16 @@ let decr_conflict_credit doms dom = - let before = dom.Domain.conflict_credit in - let after = max (-1.0) (before -. 1.0) in - dom.Domain.conflict_credit <- after; -+ let newly_penalised = -+ before >= !Define.conflict_burst_limit -+ && after < !Define.conflict_burst_limit in -+ let newly_paused = before > 0.0 && after <= 0.0 in - if !Define.conflict_rate_limit_is_aggregate then ( -- if before >= !Define.conflict_burst_limit -- && after < !Define.conflict_burst_limit -+ if newly_penalised - && after > 0.0 - then ( - push dom doms.doms_with_conflict_penalty -- ) else if before > 0.0 && after <= 0.0 -+ ) else if newly_paused - then ( - let first_pause = Queue.is_empty doms.doms_conflict_paused in - push dom doms.doms_conflict_paused; -@@ -144,9 +166,12 @@ let decr_conflict_credit doms dom = - ) else ( - (* The queues are correct already: no further action needed. *) - ) -- ) else if before > 0.0 && after <= 0.0 then ( -- doms.n_paused <- doms.n_paused + 1; -- if doms.n_paused = 1 then doms.on_first_conflict_pause () -+ ) else ( -+ if newly_penalised then doms.n_penalised <- doms.n_penalised + 1; -+ if newly_paused then ( -+ doms.n_paused <- doms.n_paused + 1; -+ if doms.n_paused = 1 then doms.on_first_conflict_pause () -+ ) - ) - - (* Give one point of credit to one domain, and update the queues appropriately. *) -@@ -175,9 +200,13 @@ let incr_conflict_credit doms = - let before = dom.Domain.conflict_credit in - let after = min (before +. 1.0) !Define.conflict_burst_limit in - dom.Domain.conflict_credit <- after; -+ - if before <= 0.0 && after > 0.0 -- then doms.n_paused <- doms.n_paused - 1 -+ then doms.n_paused <- doms.n_paused - 1; -+ -+ if before < !Define.conflict_burst_limit -+ && after >= !Define.conflict_burst_limit -+ then doms.n_penalised <- doms.n_penalised - 1 - in -- (* Scope for optimisation (probably tiny): avoid iteration if all domains are at max credit *) -- iter doms inc -+ if doms.n_penalised > 0 then iter doms inc - ) -diff --git a/tools/ocaml/xenstored/xenstored.ml b/tools/ocaml/xenstored/xenstored.ml -index d5c50fd..06387a8 100644 ---- a/tools/ocaml/xenstored/xenstored.ml -+++ b/tools/ocaml/xenstored/xenstored.ml -@@ -437,7 +437,10 @@ let _ = - peaceful_mw; - let start_time = Unix.gettimeofday () in - let timeout = -- let until_next_activity = min (max 0. (!next_frequent_ops -. start_time)) period_ops_interval in -+ let until_next_activity = -+ if Domains.all_at_max_credit domains -+ then period_ops_interval -+ else min (max 0. (!next_frequent_ops -. start_time)) period_ops_interval in - if peaceful_mw <> [] then 0. else until_next_activity - in - let inset, outset = Connections.select ~only_if:is_peaceful cons in --- -2.1.4 - |