From a43aca973eb867bee632d521c49fd620904e0d1a Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Tue, 31 Jan 2017 22:53:29 +0100 Subject: system: Introduce 'file-systems' Shepherd service. * gnu/services/base.scm (file-system-shepherd-services): New procedure. (file-system-service-type): Use it as the SHEPHERD-ROOT-SERVICE-TYPE extension. (user-processes-service-type): Change to take a single 'grace-delay' parameter. (user-processes-service): Remove 'file-systems' parameter. Pass GRACE-DELAY as the only value for the service. * gnu/system.scm (essential-services): Adjust accordingly. --- gnu/services/base.scm | 169 ++++++++++++++++++++++++++------------------------ gnu/system.scm | 5 +- 2 files changed, 91 insertions(+), 83 deletions(-) diff --git a/gnu/services/base.scm b/gnu/services/base.scm index ef4d4b723e..ecabf78429 100644 --- a/gnu/services/base.scm +++ b/gnu/services/base.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2013, 2014, 2015, 2016 Ludovic Courtès +;;; Copyright © 2013, 2014, 2015, 2016, 2017 Ludovic Courtès ;;; Copyright © 2015, 2016 Alex Kost ;;; Copyright © 2015, 2016 Mark H Weaver ;;; Copyright © 2015 Sou Bunnbu @@ -313,13 +313,26 @@ (define (file-system-shepherd-service file-system) #:select (mount-file-system)) ,@%default-modules))))))) +(define (file-system-shepherd-services file-systems) + "Return the list of Shepherd services for FILE-SYSTEMS." + (let* ((file-systems (filter file-system-mount? file-systems))) + (define sink + (shepherd-service + (provision '(file-systems)) + (requirement (cons* 'root-file-system 'user-file-systems + (map file-system->shepherd-service-name + file-systems))) + (documentation "Target for all the initially-mounted file systems") + (start #~(const #t)) + (stop #~(const #f)))) + + (cons sink (map file-system-shepherd-service file-systems)))) + (define file-system-service-type (service-type (name 'file-systems) (extensions (list (service-extension shepherd-root-service-type - (lambda (file-systems) - (filter-map file-system-shepherd-service - file-systems))) + file-system-shepherd-services) (service-extension fstab-service-type identity))) (compose concatenate) @@ -366,93 +379,89 @@ (define %do-not-kill-file (define user-processes-service-type (shepherd-service-type 'user-processes - (match-lambda - ((requirements grace-delay) - (shepherd-service - (documentation "When stopped, terminate all user processes.") - (provision '(user-processes)) - (requirement (cons* 'root-file-system 'user-file-systems - (map file-system->shepherd-service-name - requirements))) - (start #~(const #t)) - (stop #~(lambda _ - (define (kill-except omit signal) - ;; Kill all the processes with SIGNAL except those listed - ;; in OMIT and the current process. - (let ((omit (cons (getpid) omit))) - (for-each (lambda (pid) - (unless (memv pid omit) - (false-if-exception - (kill pid signal)))) - (processes)))) - - (define omitted-pids - ;; List of PIDs that must not be killed. - (if (file-exists? #$%do-not-kill-file) - (map string->number - (call-with-input-file #$%do-not-kill-file - (compose string-tokenize - (@ (ice-9 rdelim) read-string)))) - '())) - - (define (now) - (car (gettimeofday))) - - (define (sleep* n) - ;; Really sleep N seconds. - ;; Work around . - (define start (now)) - (let loop ((elapsed 0)) - (when (> n elapsed) - (sleep (- n elapsed)) - (loop (- (now) start))))) - - (define lset= (@ (srfi srfi-1) lset=)) - - (display "sending all processes the TERM signal\n") - - (if (null? omitted-pids) - (begin - ;; Easy: terminate all of them. - (kill -1 SIGTERM) - (sleep* #$grace-delay) - (kill -1 SIGKILL)) - (begin - ;; Kill them all except OMITTED-PIDS. XXX: We would - ;; like to (kill -1 SIGSTOP) to get a fixed list of - ;; processes, like 'killall5' does, but that seems - ;; unreliable. - (kill-except omitted-pids SIGTERM) - (sleep* #$grace-delay) - (kill-except omitted-pids SIGKILL) - (delete-file #$%do-not-kill-file))) - - (let wait () - (let ((pids (processes))) - (unless (lset= = pids (cons 1 omitted-pids)) - (format #t "waiting for process termination\ + (lambda (grace-delay) + (shepherd-service + (documentation "When stopped, terminate all user processes.") + (provision '(user-processes)) + (requirement '(file-systems)) + (start #~(const #t)) + (stop #~(lambda _ + (define (kill-except omit signal) + ;; Kill all the processes with SIGNAL except those listed + ;; in OMIT and the current process. + (let ((omit (cons (getpid) omit))) + (for-each (lambda (pid) + (unless (memv pid omit) + (false-if-exception + (kill pid signal)))) + (processes)))) + + (define omitted-pids + ;; List of PIDs that must not be killed. + (if (file-exists? #$%do-not-kill-file) + (map string->number + (call-with-input-file #$%do-not-kill-file + (compose string-tokenize + (@ (ice-9 rdelim) read-string)))) + '())) + + (define (now) + (car (gettimeofday))) + + (define (sleep* n) + ;; Really sleep N seconds. + ;; Work around . + (define start (now)) + (let loop ((elapsed 0)) + (when (> n elapsed) + (sleep (- n elapsed)) + (loop (- (now) start))))) + + (define lset= (@ (srfi srfi-1) lset=)) + + (display "sending all processes the TERM signal\n") + + (if (null? omitted-pids) + (begin + ;; Easy: terminate all of them. + (kill -1 SIGTERM) + (sleep* #$grace-delay) + (kill -1 SIGKILL)) + (begin + ;; Kill them all except OMITTED-PIDS. XXX: We would + ;; like to (kill -1 SIGSTOP) to get a fixed list of + ;; processes, like 'killall5' does, but that seems + ;; unreliable. + (kill-except omitted-pids SIGTERM) + (sleep* #$grace-delay) + (kill-except omitted-pids SIGKILL) + (delete-file #$%do-not-kill-file))) + + (let wait () + (let ((pids (processes))) + (unless (lset= = pids (cons 1 omitted-pids)) + (format #t "waiting for process termination\ (processes left: ~s)~%" - pids) - (sleep* 2) - (wait)))) + pids) + (sleep* 2) + (wait)))) - (display "all processes have been terminated\n") - #f)) - (respawn? #f)))))) + (display "all processes have been terminated\n") + #f)) + (respawn? #f))))) -(define* (user-processes-service file-systems #:key (grace-delay 4)) +(define* (user-processes-service #:key (grace-delay 4)) "Return the service that is responsible for terminating all the processes so that the root file system can be re-mounted read-only, just before rebooting/halting. Processes still running GRACE-DELAY seconds after SIGTERM has been sent are terminated with SIGKILL. -The returned service will depend on 'root-file-system' and on all the shepherd -services corresponding to FILE-SYSTEMS. +The returned service will depend on 'file-systems', meaning that it is +considered started after all the auto-mount file systems have been mounted. All the services that spawn processes must depend on this one so that they are stopped before 'kill' is called." - (service user-processes-service-type - (list (filter file-system-mount? file-systems) grace-delay))) + (service user-processes-service-type grace-delay)) ;;; diff --git a/gnu/system.scm b/gnu/system.scm index 4e57f975e6..1006c842c9 100644 --- a/gnu/system.scm +++ b/gnu/system.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2013, 2014, 2015, 2016 Ludovic Courtès +;;; Copyright © 2013, 2014, 2015, 2016, 2017 Ludovic Courtès ;;; Copyright © 2015 Mark H Weaver ;;; Copyright © 2015, 2016 Alex Kost ;;; Copyright © 2016 Chris Marusich @@ -293,8 +293,7 @@ (define known-fs (other-fs (non-boot-file-system-service os)) (unmount (user-unmount-service known-fs)) (swaps (swap-services os)) - (procs (user-processes-service - (service-parameters other-fs))) + (procs (user-processes-service)) (host-name (host-name-service (operating-system-host-name os))) (entries (operating-system-directory-base-entries os #:container? container?))) -- cgit v1.2.3