From de29a260082bb35881a6eec2260bb4c8a2d538b3 Mon Sep 17 00:00:00 2001 From: Maxime Devos Date: Sat, 23 Jul 2022 21:08:23 +0200 Subject: [PATCH] =?UTF-8?q?guile-fibers:=20Backport=20the=20=E2=80=98epoll?= =?UTF-8?q?=20instance=20is=20dead=E2=80=99=20bugfix.?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This fixes some indeterministic test failures for gnunet-scheme observed while developing gnunet-scheme. The following checks were made: All dependents compile for x86_64: $ ./pre-inst-env guix build shepherd gnunet-scheme guix-build-coordinator nar-herder guix-data-service guile-fibers --system=x86_64-linux Everything except guix-build-coordinator (which depends on the non-cross-compilable sqitch) cross-compile from x86_64 to aarch64-linux-gnu: $ ./pre-inst-env guix build shepherd gnunet-scheme nar-herder guile-fibers --system=x86_64-linux --target=aarch64-linux-gnu I tried testing for reproducibility but the check phase took to long. However, you can compare the hash you get against the hash I got: $ ./pre-inst-env guix hash --serializer=nar $(./pre-inst-env guix build guile-fibers --no-grafts --system=x86_64-linux) 0qsaqx27b6q2s22h7y93417ijpkwl6gc1fhhck8aha6bvmawk5h0 I tried an emulated build for another architecture, but there the tests took overly long. There were no lint warnings for guile-fibers. * gnu/packages/patches/guile-fibers-epoll-instance-is-dead.patch: New patch. * gnu/local.mk (dist_patch_DATA): Register the patch. * gnu/packages/guile-xyz.scm (guile-fibers)[source]{patches}: Use the patch. Signed-off-by: Mathieu Othacehe --- gnu/local.mk | 1 + gnu/packages/guile-xyz.scm | 3 +- .../guile-fibers-epoll-instance-is-dead.patch | 99 +++++++++++++++++++ 3 files changed, 102 insertions(+), 1 deletion(-) create mode 100644 gnu/packages/patches/guile-fibers-epoll-instance-is-dead.patch diff --git a/gnu/local.mk b/gnu/local.mk index 2d32d85d47..882b13420b 100644 --- a/gnu/local.mk +++ b/gnu/local.mk @@ -1254,6 +1254,7 @@ dist_patch_DATA = \ %D%/packages/patches/guile-ac-d-bus-fix-tests.patch \ %D%/packages/patches/guile-cross-compilation.patch \ %D%/packages/patches/guile-fibers-destroy-peer-schedulers.patch \ + %D%/packages/patches/guile-fibers-epoll-instance-is-dead.patch \ %D%/packages/patches/guile-fibers-wait-for-io-readiness.patch \ %D%/packages/patches/guile-gdbm-ffi-support-gdbm-1.14.patch \ %D%/packages/patches/guile-git-adjust-for-libgit2-1.2.0.patch \ diff --git a/gnu/packages/guile-xyz.scm b/gnu/packages/guile-xyz.scm index fc6fa37f73..72b4b87d44 100644 --- a/gnu/packages/guile-xyz.scm +++ b/gnu/packages/guile-xyz.scm @@ -621,7 +621,8 @@ (define-public guile-fibers-1.1 (base32 "0ll63d7202clapg1k4bilbnlmfa4qvpjnsd7chbkka4kxf5klilc")) (patches - (search-patches "guile-fibers-wait-for-io-readiness.patch")))) + (search-patches "guile-fibers-wait-for-io-readiness.patch" + "guile-fibers-epoll-instance-is-dead.patch")))) (build-system gnu-build-system) (native-inputs (list texinfo pkg-config autoconf automake libtool diff --git a/gnu/packages/patches/guile-fibers-epoll-instance-is-dead.patch b/gnu/packages/patches/guile-fibers-epoll-instance-is-dead.patch new file mode 100644 index 0000000000..ba191f765d --- /dev/null +++ b/gnu/packages/patches/guile-fibers-epoll-instance-is-dead.patch @@ -0,0 +1,99 @@ +From 5db4077e9f5166033637d2af9532ec6144b85646 Mon Sep 17 00:00:00 2001 +From: Maxime Devos +Date: Thu, 30 Jun 2022 14:21:47 +0000 +Subject: [PATCH 1/2] Fix behaviour of 'epoll-wake!' after 'run-fibers'. + +This avoids the "epoll instance is dead" error noticed in +GNUnet-Scheme's test suite, as reported at +. +A test is added in the next commit. + +This patch has been applied upstream, but there hasn't been +a new release yet at time of writing. + +* fibers/epoll.scm (epoll-wake!)[dead]: Instead of throwing an error, +just return #t. +--- + fibers/epoll.scm | 8 +++++++- + 1 file changed, 7 insertions(+), 1 deletion(-) + +diff --git a/fibers/epoll.scm b/fibers/epoll.scm +index d26db4d..eb63242 100644 +--- a/fibers/epoll.scm ++++ b/fibers/epoll.scm +@@ -1,6 +1,7 @@ + ;; epoll + + ;;;; Copyright (C) 2016 Andy Wingo ++;;;; Copyright (C) 2022 Maxime Devos + ;;;; + ;;;; This library is free software; you can redistribute it and/or + ;;;; modify it under the terms of the GNU Lesser General Public +@@ -135,7 +136,12 @@ epoll wait (if appropriate)." + ('waiting + (primitive-epoll-wake (fileno (epoll-wake-write-pipe epoll)))) + ('not-waiting #t) +- ('dead (error "epoll instance is dead")))) ++ ;; This can happen if a fiber was waiting on a condition and ++ ;; run-fibers completes before the fiber completes and afterwards ++ ;; the condition is signalled. In that case, we don't have to ++ ;; resurrect the fiber or something, we can just do nothing. ++ ;; (Bug report: https://github.com/wingo/fibers/issues/61) ++ ('dead #t))) + + (define (epoll-default-folder fd events seed) + (acons fd events seed)) + +From c01d3853eb56ea4adacc31f51f6e917f8c0abe1c Mon Sep 17 00:00:00 2001 +From: Maxime Devos +Date: Thu, 30 Jun 2022 14:18:36 +0000 +Subject: [PATCH 2/2] Test for issue #61. + +* tests/conditions.scm: Add a test. +--- + tests/conditions.scm | 20 ++++++++++++++++++++ + 1 file changed, 20 insertions(+) + +diff --git a/tests/conditions.scm b/tests/conditions.scm +index 505c42a..179605a 100644 +--- a/tests/conditions.scm ++++ b/tests/conditions.scm +@@ -1,6 +1,7 @@ + ;; Fibers: cooperative, event-driven user-space threads. + + ;;;; Copyright (C) 2016 Free Software Foundation, Inc. ++;;;; Copyright (C) 2022 Maxime Devos + ;;;; + ;;;; This library is free software; you can redistribute it and/or + ;;;; modify it under the terms of the GNU Lesser General Public +@@ -21,6 +22,7 @@ + #:use-module (fibers) + #:use-module (fibers conditions) + #:use-module (fibers operations) ++ #:use-module (fibers scheduler) + #:use-module (fibers timers)) + + (define failed? #f) +@@ -78,4 +80,22 @@ + (wait cv) + #t)) + ++;; Make a condition, wait for it inside a fiber, let the fiber abruptly ++;; terminate and signal the condition afterwards. This tests for the bug ++;; noticed at . ++(assert-equal #t ++ (let ((cv (make-condition))) ++ (run-fibers ++ (lambda () ++ (spawn-fiber (lambda () (wait cv))) ++ (yield-current-task)) ; let the other fiber wait forever ++ ;; This test relies on not draining -- this is the default, ++ ;; but let's make this explicit. ++ #:drain? #false ; ++ ;; For simplicity, disable concurrency and preemption. ++ ;; That way, we can use 'yield-current-task' instead of an ++ ;; arbitrary sleep time. ++ #:hz 0 #:parallelism 1) ++ (signal-condition! cv))) ++ + (exit (if failed? 1 0))