@@ -18,12 +18,12 @@ OCAMLINCLUDE += \
-I $(OCAML_TOPLEVEL)/libs/xc \
-I $(OCAML_TOPLEVEL)/libs/eventchn
-LIBS = syslog.cma syslog.cmxa select.cma select.cmxa
+LIBS = syslog.cma syslog.cmxa poll.cma poll.cmxa
syslog_OBJS = syslog
syslog_C_OBJS = syslog_stubs
-select_OBJS = select
-select_C_OBJS = select_stubs
-OCAML_LIBRARY = syslog select
+poll_OBJS = poll
+poll_C_OBJS = select_stubs
+OCAML_LIBRARY = syslog poll
LIBS += systemd.cma systemd.cmxa
systemd_OBJS = systemd
@@ -58,13 +58,13 @@ OBJS = paths \
process \
xenstored
-INTF = symbol.cmi trie.cmi syslog.cmi systemd.cmi select.cmi
+INTF = symbol.cmi trie.cmi syslog.cmi systemd.cmi poll.cmi
XENSTOREDLIBS = \
unix.cmxa \
-ccopt -L -ccopt . syslog.cmxa \
-ccopt -L -ccopt . systemd.cmxa \
- -ccopt -L -ccopt . select.cmxa \
+ -ccopt -L -ccopt . poll.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/mmap $(OCAML_TOPLEVEL)/libs/mmap/xenmmap.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/eventchn $(OCAML_TOPLEVEL)/libs/eventchn/xeneventchn.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/xc $(OCAML_TOPLEVEL)/libs/xc/xenctrl.cmxa \
@@ -25,7 +25,6 @@ type config =
tracefile: string option; (* old xenstored compatibility *)
restart: bool;
disable_socket: bool;
- use_select: bool;
}
let do_argv =
@@ -37,7 +36,7 @@ let do_argv =
and config_file = ref ""
and restart = ref false
and disable_socket = ref false
- and use_select = ref false in
+ in
let speclist =
[ ("--no-domain-init", Arg.Unit (fun () -> domain_init := false),
@@ -54,9 +53,8 @@ let do_argv =
("-T", Arg.Set_string tracefile, ""); (* for compatibility *)
("--restart", Arg.Set restart, "Read database on starting");
("--disable-socket", Arg.Unit (fun () -> disable_socket := true), "Disable socket");
- ("--use-select", Arg.Unit (fun () -> use_select := true), "Use select instead of poll"); (* for backward compatibility and testing *)
] in
- let usage_msg = "usage : xenstored [--config-file <filename>] [--no-domain-init] [--help] [--no-fork] [--reraise-top-level] [--restart] [--disable-socket] [--use-select]" in
+ let usage_msg = "usage : xenstored [--config-file <filename>] [--no-domain-init] [--help] [--no-fork] [--reraise-top-level] [--restart] [--disable-socket]" in
Arg.parse speclist (fun _ -> ()) usage_msg;
{
domain_init = !domain_init;
@@ -68,5 +66,4 @@ let do_argv =
tracefile = if !tracefile <> "" then Some !tracefile else None;
restart = !restart;
disable_socket = !disable_socket;
- use_select = !use_select;
}
similarity index 85%
rename from tools/ocaml/xenstored/select.ml
rename to tools/ocaml/xenstored/poll.ml
@@ -63,15 +63,5 @@ let poll_select in_fds out_fds exc_fds timeout =
(if event.except then fd :: x else x))
a r
-(* If the use_poll function is not called at all, we default to the original Unix.select behavior *)
-let select_fun = ref Unix.select
-
-let use_poll yes =
- let sel_fun, max_fd =
- if yes then poll_select, get_sys_fs_nr_open ()
- else Unix.select, 1024 in
- select_fun := sel_fun;
- set_fd_limit max_fd
-
-let select in_fds out_fds exc_fds timeout =
- (!select_fun) in_fds out_fds exc_fds timeout
+let () =
+ set_fd_limit (get_sys_fs_nr_open ())
similarity index 58%
rename from tools/ocaml/xenstored/select.mli
rename to tools/ocaml/xenstored/poll.mli
@@ -13,15 +13,7 @@
*)
-(** Same interface and semantics as [Unix.select] but with an extra alternative
- implementation based on poll. Switching implementations is done by calling
- the [use_poll] function. *)
-val select:
+(** Same interface and semantics as [Unix.select], implemented using poll(3). *)
+val poll_select:
Unix.file_descr list -> Unix.file_descr list -> Unix.file_descr list -> float
-> Unix.file_descr list * Unix.file_descr list * Unix.file_descr list
-
-(** [use_poll true] will use poll based select with max fds number limitation
- eliminated; [use_poll false] will use standard [Unix.select] with max fd
- number set to 1024; not calling this function at all equals to use the
- standard [Unix.select] with max fd number setting untouched. *)
-val use_poll: bool -> unit
@@ -308,8 +308,6 @@ let _ =
);
);
- Select.use_poll (not cf.use_select);
-
Sys.set_signal Sys.sighup (Sys.Signal_handle sighup_handler);
Sys.set_signal Sys.sigterm (Sys.Signal_handle (fun _ -> quit := true));
Sys.set_signal Sys.sigusr1 (Sys.Signal_handle (fun _ -> sigusr1_handler store));
@@ -441,7 +439,7 @@ let _ =
let inset, outset = Connections.select ~only_if:is_peaceful cons in
let rset, wset, _ =
try
- Select.select (spec_fds @ inset) outset [] timeout
+ Poll.poll_select (spec_fds @ inset) outset [] timeout
with Unix.Unix_error(Unix.EINTR, _, _) ->
[], [], [] in
let sfds, cfds =
Poll has been the default since 2014, I think we can safely say by now that poll() works and we don't need to fall back to select(). This will allow fixing up the way we call poll to be more efficient (and pave the way for introducing epoll support): currently poll wraps the select API, which is inefficient. Signed-off-by: Edwin Török <edvin.torok@citrix.com> --- Changed since v1: * fix commit title --- tools/ocaml/xenstored/Makefile | 12 ++++++------ tools/ocaml/xenstored/parse_arg.ml | 7 ++----- tools/ocaml/xenstored/{select.ml => poll.ml} | 14 ++------------ tools/ocaml/xenstored/{select.mli => poll.mli} | 12 ++---------- tools/ocaml/xenstored/xenstored.ml | 4 +--- 5 files changed, 13 insertions(+), 36 deletions(-) rename tools/ocaml/xenstored/{select.ml => poll.ml} (85%) rename tools/ocaml/xenstored/{select.mli => poll.mli} (58%)