From 4245ddcbc9f935804c17c97872b90ec1050c2d75 Mon Sep 17 00:00:00 2001 From: Carlo Zancanaro Date: Sun, 26 Aug 2018 21:54:14 +1000 Subject: guix system: Load all services on reconfigure, not just stopped ones. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This uses the 'replacement' service slot introduced in the Shepherd version 0.5.0. * gnu/services/shepherd.scm (shepherd-service-upgrade): Return a list of services that need to be restarted to complete their upgrade. * guix/scripts/system.scm (call-with-service-upgrade-info): Rename an internal variable to reflect the change to shepherd-service-upgrade. (upgrade-shepherd-services): Call 'load-services/safe' instead of 'load-services'. Print a message about services that need to be manually restarted. * gnu/services/herd.scm (load-services/safe): New procedure. * doc/guix.texi (Invoking guix system): Document the new behaviour. Co-authored-by: Ludovic Courtès --- doc/guix.texi | 8 ++++---- gnu/services/herd.scm | 20 ++++++++++++++++++++ gnu/services/shepherd.scm | 23 ++++++++--------------- guix/scripts/system.scm | 25 ++++++++++++++++--------- 4 files changed, 48 insertions(+), 28 deletions(-) diff --git a/doc/guix.texi b/doc/guix.texi index 6b4b06f46d..e1046eb512 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -33,7 +33,7 @@ Copyright @copyright{} 2016 Alex ter Weele@* Copyright @copyright{} 2017, 2018 Clément Lassieur@* Copyright @copyright{} 2017 Mathieu Othacehe@* Copyright @copyright{} 2017 Federico Beffa@* -Copyright @copyright{} 2017 Carlo Zancanaro@* +Copyright @copyright{} 2017, 2018 Carlo Zancanaro@* Copyright @copyright{} 2017 Thomas Danckaert@* Copyright @copyright{} 2017 humanitiesNerd@* Copyright @copyright{} 2017 Christopher Allan Webber@* @@ -21920,9 +21920,9 @@ systems already running GuixSD.}. This effects all the configuration specified in @var{file}: user accounts, system services, global package list, setuid programs, etc. The command starts system services specified in @var{file} that are not -currently running; if a service is currently running, it does not -attempt to upgrade it since this would not be possible without stopping it -first. +currently running; if a service is currently running this command will +arrange for it to be upgraded the next time it is stopped (eg. by +@code{herd stop X} or @code{herd restart X}). This command creates a new generation whose number is one greater than the current generation (as reported by @command{guix system diff --git a/gnu/services/herd.scm b/gnu/services/herd.scm index 8c96b70731..8ff817759d 100644 --- a/gnu/services/herd.scm +++ b/gnu/services/herd.scm @@ -50,6 +50,7 @@ unload-services unload-service load-services + load-services/safe start-service stop-service)) @@ -232,6 +233,25 @@ returns a shepherd object." `(primitive-load ,file)) files)))) +(define (load-services/safe files) + "This is like 'load-services', but make sure only the subset of FILES that +can be safely reloaded is actually reloaded. + +This is done to accommodate the Shepherd < 0.15.0 where services lacked the +'replacement' slot, and where 'register-services' would throw an exception +when passed a service with an already-registered name." + (eval-there `(let* ((services (map primitive-load ',files)) + (slots (map slot-definition-name + (class-slots ))) + (can-replace? (memq 'replacement slots))) + (define (registered? service) + (not (null? (lookup-services (canonical-name service))))) + + (apply register-services + (if can-replace? + services + (remove registered? services)))))) + (define (start-service name) (with-shepherd-action name ('start) result result)) diff --git a/gnu/services/shepherd.scm b/gnu/services/shepherd.scm index 4cd2249841..4c7e72049f 100644 --- a/gnu/services/shepherd.scm +++ b/gnu/services/shepherd.scm @@ -1,6 +1,7 @@ ;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2013, 2014, 2015, 2016, 2018 Ludovic Courtès ;;; Copyright © 2017 Clément Lassieur +;;; Copyright © 2018 Carlo Zancanaro ;;; ;;; This file is part of GNU Guix. ;;; @@ -329,7 +330,7 @@ symbols provided/required by a service." (define (shepherd-service-upgrade live target) "Return two values: the subset of LIVE (a list of ) that needs to be unloaded, and the subset of TARGET (a list of ) that -needs to be loaded." +need to be restarted to complete their upgrade." (define (essential? service) (memq (first (live-service-provision service)) '(root shepherd))) @@ -346,12 +347,6 @@ needs to be loaded." (and=> (lookup-live (shepherd-service-canonical-name service)) live-service-running)) - (define (stopped service) - (match (lookup-live (shepherd-service-canonical-name service)) - (#f #f) - (service (and (not (live-service-running service)) - service)))) - (define live-service-dependents (shepherd-service-back-edges live #:provision live-service-provision @@ -362,16 +357,14 @@ needs to be loaded." (#f (every obsolete? (live-service-dependents service))) (_ #f))) - (define to-load - ;; Only load services that are either new or currently stopped. - (remove running? target)) + (define to-restart + ;; Restart services that are currently running. + (filter running? target)) (define to-unload - ;; Unload services that are (1) no longer required, or (2) are in TO-LOAD. - (remove essential? - (append (filter obsolete? live) - (filter-map stopped to-load)))) + ;; Unload services that are no longer required. + (remove essential? (filter obsolete? live))) - (values to-unload to-load)) + (values to-unload to-restart)) ;;; shepherd.scm ends here diff --git a/guix/scripts/system.scm b/guix/scripts/system.scm index 69bd05b516..1e7620f147 100644 --- a/guix/scripts/system.scm +++ b/guix/scripts/system.scm @@ -310,9 +310,9 @@ names of services to load (upgrade), and the list of names of services to unload." (match (current-services) ((services ...) - (let-values (((to-unload to-load) + (let-values (((to-unload to-restart) (shepherd-service-upgrade services new-services))) - (mproc to-load + (mproc to-restart (map (compose first live-service-provision) to-unload)))) (#f @@ -335,25 +335,32 @@ bring the system down." ;; Arrange to simply emit a warning if the service upgrade fails. (with-shepherd-error-handling (call-with-service-upgrade-info new-services - (lambda (to-load to-unload) + (lambda (to-restart to-unload) (for-each (lambda (unload) (info (G_ "unloading service '~a'...~%") unload) (unload-service unload)) to-unload) (with-monad %store-monad - (munless (null? to-load) - (let ((to-load-names (map shepherd-service-canonical-name to-load)) - (to-start (filter shepherd-service-auto-start? to-load))) - (info (G_ "loading new services:~{ ~a~}...~%") to-load-names) + (munless (null? new-services) + (let ((new-service-names (map shepherd-service-canonical-name new-services)) + (to-restart-names (map shepherd-service-canonical-name to-restart)) + (to-start (filter shepherd-service-auto-start? new-services))) + (info (G_ "loading new services:~{ ~a~}...~%") new-service-names) + (unless (null? to-restart-names) + ;; Listing TO-RESTART-NAMES in the message below wouldn't help + ;; because many essential services cannot be meaningfully + ;; restarted. See . + (format #t (G_ "To complete the upgrade, run 'herd restart SERVICE' to stop, +upgrade, and restart each service that was not automatically restarted.\n"))) (mlet %store-monad ((files (mapm %store-monad (compose lower-object shepherd-service-file) - to-load))) + new-services))) ;; Here we assume that FILES are exactly those that were computed ;; as part of the derivation that built OS, which is normally the ;; case. - (load-services (map derivation->output-path files)) + (load-services/safe (map derivation->output-path files)) (for-each start-service (map shepherd-service-canonical-name to-start)) -- cgit 1.4.1