From 64a7ef8bc06b5dcfcd9f99ea10a43bde75c4370f Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 3 Aug 2018 16:43:30 +0200 Subject: man: be more explicit about thread safety of sd_journal Triggered by https://bugzilla.redhat.com/show_bug.cgi?id=1609349 This adds two generic paragaphs we include via xinclude. One is the "strict" version, which contains wording saying that we are thread agnostic and what that means. And the other is the "safe" version, for the cases we provide fully safety. Let's then change most man pages to use either of these generic paragraphs. With one exception: man/sd_journal_get_catalog.xml contains both kinds of function, we hence use manual wording. --- man/libudev.xml | 8 +++----- man/sd-journal.xml | 17 ++++++++--------- man/sd_journal_enumerate_fields.xml | 3 +-- man/sd_journal_get_catalog.xml | 11 ++++++++--- man/sd_journal_get_cursor.xml | 3 +-- man/sd_journal_get_cutoff_realtime_usec.xml | 3 +-- man/sd_journal_get_data.xml | 8 +++++++- man/sd_journal_get_fd.xml | 11 +++-------- man/sd_journal_get_realtime_usec.xml | 8 +++++++- man/sd_journal_get_usage.xml | 3 +-- man/sd_journal_has_runtime_files.xml | 3 +-- man/sd_journal_next.xml | 3 +-- man/sd_journal_open.xml | 13 ++++--------- man/sd_journal_print.xml | 3 ++- man/sd_journal_query_unique.xml | 3 +-- man/sd_journal_seek_head.xml | 3 +-- man/sd_journal_stream_fd.xml | 3 +-- man/threads-aware.xml | 17 +++++++++++++++++ 18 files changed, 68 insertions(+), 55 deletions(-) create mode 100644 man/threads-aware.xml (limited to 'man') diff --git a/man/libudev.xml b/man/libudev.xml index 8cb4ba59f..382c1aa25 100644 --- a/man/libudev.xml +++ b/man/libudev.xml @@ -48,11 +48,9 @@ udev_new3. It is used to track library state and link objects together. No global state is used by libudev, everything is always linked to - a udev context. Furthermore, multiple different udev contexts can - be used in parallel by multiple threads. However, a single context - must not be accessed by multiple threads in parallel. The caller - is responsible for providing suitable locking if they intend to use - it from multiple threads. + a udev context. + + To introspect a local device on a system, a udev device object can be created via diff --git a/man/sd-journal.xml b/man/sd-journal.xml index 8bfcb90ca..3fa6c75b7 100644 --- a/man/sd-journal.xml +++ b/man/sd-journal.xml @@ -77,16 +77,15 @@ Thread safety - Functions that operate on the sd_journal object are thread - agnostic — given sd_journal pointer may only be used from one thread at - a time, but multiple threads may use multiple such objects safely. Other functions — - those that are used to send entries to the journal, like - sd_journal_print3 - and similar, or those that are used to retrieve global information like - sd_journal_stream_fd3 - and + Functions that operate on sd_journal objects are thread agnostic — given + sd_journal pointer may only be used from one specific thread at all times (and it has to + be the very same one during the entire lifetime of the object), but multiple, independent threads may use multiple, + independent objects safely. Other functions — those that are used to send entries to the journal, like + sd_journal_print3 and similar, + or those that are used to retrieve global information like + sd_journal_stream_fd3 and sd_journal_get_catalog_for_message_id3 - — are thread-safe and may be called from multiple threads in parallel. + — are fully thread-safe and may be called from multiple threads in parallel. diff --git a/man/sd_journal_enumerate_fields.xml b/man/sd_journal_enumerate_fields.xml index 95af2c1ee..c5704f53a 100644 --- a/man/sd_journal_enumerate_fields.xml +++ b/man/sd_journal_enumerate_fields.xml @@ -86,8 +86,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_get_catalog.xml b/man/sd_journal_get_catalog.xml index ce37e177b..80edc08c8 100644 --- a/man/sd_journal_get_catalog.xml +++ b/man/sd_journal_get_catalog.xml @@ -87,9 +87,14 @@ Notes - Function sd_journal_get_catalog() is thread-agnostic and only a - single thread may operate on a given sd_journal object. Function - sd_journal_get_catalog_for_message_id() is thread-safe. + Function sd_journal_get_catalog() is thread-agnostic and only + a single specific thread may operate on a given object during its entire lifetime. It's safe to allocate multiple + independent objects and use each from a specific thread in parallel. However, it's not safe to allocate such an + object in one thread, and operate or free it from any other, even if locking is used to ensure these threads don't + operate on it at the very same time. + + Function sd_journal_get_catalog_for_message_id() is are thread-safe and may be called in + parallel from multiple threads. diff --git a/man/sd_journal_get_cursor.xml b/man/sd_journal_get_cursor.xml index 6817a3cd5..d5e465b81 100644 --- a/man/sd_journal_get_cursor.xml +++ b/man/sd_journal_get_cursor.xml @@ -98,8 +98,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_get_cutoff_realtime_usec.xml b/man/sd_journal_get_cutoff_realtime_usec.xml index dc8e32bf8..b2a0634f7 100644 --- a/man/sd_journal_get_cutoff_realtime_usec.xml +++ b/man/sd_journal_get_cutoff_realtime_usec.xml @@ -96,8 +96,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_get_data.xml b/man/sd_journal_get_data.xml index 99f950044..464fd16ac 100644 --- a/man/sd_journal_get_data.xml +++ b/man/sd_journal_get_data.xml @@ -156,7 +156,13 @@ success or a negative errno-style error code. - + + Notes + + + + + Examples diff --git a/man/sd_journal_get_fd.xml b/man/sd_journal_get_fd.xml index 7edbc4bc2..2186b685b 100644 --- a/man/sd_journal_get_fd.xml +++ b/man/sd_journal_get_fd.xml @@ -226,14 +226,9 @@ else { Notes - The sd_journal_get_fd(), - sd_journal_get_events(), - sd_journal_reliable_fd(), - sd_journal_process() and - sd_journal_wait() interfaces are available as - a shared library, which can be compiled and linked to with the - libsystemd pkg-config1 - file. + + + diff --git a/man/sd_journal_get_realtime_usec.xml b/man/sd_journal_get_realtime_usec.xml index 2030e8372..e0f5c4d2e 100644 --- a/man/sd_journal_get_realtime_usec.xml +++ b/man/sd_journal_get_realtime_usec.xml @@ -89,7 +89,13 @@ sd_journal_get_monotonic_usec(). - + + Notes + + + + + See Also diff --git a/man/sd_journal_get_usage.xml b/man/sd_journal_get_usage.xml index 358a62d06..39f53dd5e 100644 --- a/man/sd_journal_get_usage.xml +++ b/man/sd_journal_get_usage.xml @@ -56,8 +56,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_has_runtime_files.xml b/man/sd_journal_has_runtime_files.xml index b7bbf224d..44fdc8d18 100644 --- a/man/sd_journal_has_runtime_files.xml +++ b/man/sd_journal_has_runtime_files.xml @@ -66,8 +66,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_next.xml b/man/sd_journal_next.xml index c0ca5a8a1..9a27d1426 100644 --- a/man/sd_journal_next.xml +++ b/man/sd_journal_next.xml @@ -122,8 +122,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_open.xml b/man/sd_journal_open.xml index 9f600b223..cf787b7ea 100644 --- a/man/sd_journal_open.xml +++ b/man/sd_journal_open.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_journal_open @@ -184,15 +185,9 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + - The sd_journal_open(), - sd_journal_open_directory() and - sd_journal_close() interfaces are available - as a shared library, which can be compiled and linked to with the - libsystemd pkg-config1 - file. + diff --git a/man/sd_journal_print.xml b/man/sd_journal_print.xml index f8ff7ba09..e18cf88bb 100644 --- a/man/sd_journal_print.xml +++ b/man/sd_journal_print.xml @@ -177,7 +177,8 @@ sd_journal_send("MESSAGE=Hello World, this is PID %lu!", (unsigned long) getpid( Thread safety - All functions listed here are thread-safe and may be called in parallel from multiple threads. + + sd_journal_sendv() is "async signal safe" in the meaning of signal-safety7. diff --git a/man/sd_journal_query_unique.xml b/man/sd_journal_query_unique.xml index c62f333ea..9adafa114 100644 --- a/man/sd_journal_query_unique.xml +++ b/man/sd_journal_query_unique.xml @@ -126,8 +126,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_seek_head.xml b/man/sd_journal_seek_head.xml index 86274071f..da88d241e 100644 --- a/man/sd_journal_seek_head.xml +++ b/man/sd_journal_seek_head.xml @@ -120,8 +120,7 @@ Notes - All functions listed here are thread-agnostic and only a single thread may operate - on a given sd_journal object. + diff --git a/man/sd_journal_stream_fd.xml b/man/sd_journal_stream_fd.xml index de76cabb4..8e65dc765 100644 --- a/man/sd_journal_stream_fd.xml +++ b/man/sd_journal_stream_fd.xml @@ -92,8 +92,7 @@ Notes - Function sd_journal_stream_fd() is thread-safe and may be called - from multiple threads. + diff --git a/man/threads-aware.xml b/man/threads-aware.xml new file mode 100644 index 000000000..7985f4acd --- /dev/null +++ b/man/threads-aware.xml @@ -0,0 +1,17 @@ + + + + + + + +All functions listed here are thread-agnostic and only a single specific thread may operate on a +given object during its entire lifetime. It's safe to allocate multiple independent objects and use each from a +specific thread in parallel. However, it's not safe to allocate such an object in one thread, and operate or free it +from any other, even if locking is used to ensure these threads don't operate on it at the very same time. + +All functions listed here are thread-safe and may be called in parallel from multiple threads. + + -- cgit v1.2.3-65-gdbad From 7647c01d8f55d5ba1c918d103773252cb09ebf23 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 3 Aug 2018 17:34:40 +0200 Subject: man: include libsystemd-pkgconfig.xml in a few more man pages for some reason this was forgotten for a couple of sd_bus man pages, let's fix that. --- man/sd-bus-errors.xml | 13 +++---------- man/sd_bus_add_match.xml | 6 ++---- man/sd_bus_error_add_map.xml | 13 +++---------- man/sd_bus_is_open.xml | 11 +++-------- man/sd_bus_path_encode.xml | 12 ++---------- man/sd_bus_request_name.xml | 11 +++-------- man/sd_bus_set_connected_signal.xml | 11 +++-------- man/sd_bus_set_sender.xml | 11 +++-------- man/sd_bus_set_watch_bind.xml | 11 +++-------- 9 files changed, 25 insertions(+), 74 deletions(-) (limited to 'man') diff --git a/man/sd-bus-errors.xml b/man/sd-bus-errors.xml index 50abf4c07..c89651154 100644 --- a/man/sd-bus-errors.xml +++ b/man/sd-bus-errors.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd-bus-errors @@ -259,15 +260,7 @@ - - Notes - - The various error definitions described here are available - as a shared library, which can be compiled and linked to with the - libsystemd pkg-config1 - file. - + See Also diff --git a/man/sd_bus_add_match.xml b/man/sd_bus_add_match.xml index a22d443ce..c4f24aed3 100644 --- a/man/sd_bus_add_match.xml +++ b/man/sd_bus_add_match.xml @@ -8,7 +8,7 @@ Copyright © 2016 Julian Orth --> - + sd_bus_add_match @@ -154,9 +154,7 @@ Notes - sd_bus_add_match() and the other functions described here are available as a shared - library, which can be compiled and linked to with the libsystemd pkg-config1 file. + diff --git a/man/sd_bus_error_add_map.xml b/man/sd_bus_error_add_map.xml index 107291f26..dbe05a189 100644 --- a/man/sd_bus_error_add_map.xml +++ b/man/sd_bus_error_add_map.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_error_add_map @@ -123,15 +124,7 @@ - - Notes - - The various error definitions described here are available - as a shared library, which can be compiled and linked to with the - libsystemd pkg-config1 - file. - + See Also diff --git a/man/sd_bus_is_open.xml b/man/sd_bus_is_open.xml index 5cd2d18c4..0388db82a 100644 --- a/man/sd_bus_is_open.xml +++ b/man/sd_bus_is_open.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_is_open @@ -88,13 +89,7 @@ - - Notes - - sd_bus_is_open() and sd_bus_is_ready() are available as - a shared library, which can be compiled and linked to with the libsystemd pkg-config1 file. - + See Also diff --git a/man/sd_bus_path_encode.xml b/man/sd_bus_path_encode.xml index 4c60a8fa3..03130a697 100644 --- a/man/sd_bus_path_encode.xml +++ b/man/sd_bus_path_encode.xml @@ -6,7 +6,7 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_path_encode @@ -141,15 +141,7 @@ by the caller. - - Notes - - sd_bus_path_encode() and - sd_bus_path_decode() are available as a - shared library, which can be compiled and linked to with the - libsystemd pkg-config1 - file. - + See Also diff --git a/man/sd_bus_request_name.xml b/man/sd_bus_request_name.xml index 54a14c877..3c98b60c6 100644 --- a/man/sd_bus_request_name.xml +++ b/man/sd_bus_request_name.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_request_name @@ -193,13 +194,7 @@ - - Notes - - The sd_bus_acquire_name() and the other interfaces described here are available as a - shared library, which can be compiled and linked to with the libsystemd pkg-config1 file. - + See Also diff --git a/man/sd_bus_set_connected_signal.xml b/man/sd_bus_set_connected_signal.xml index 9dd47bc4d..32fc630cf 100644 --- a/man/sd_bus_set_connected_signal.xml +++ b/man/sd_bus_set_connected_signal.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_set_connected_signal @@ -94,13 +95,7 @@ - - Notes - - sd_bus_set_connected_signal() and sd_bus_get_connected_signal() are available as - a shared library, which can be compiled and linked to with the libsystemd pkg-config1 file. - + See Also diff --git a/man/sd_bus_set_sender.xml b/man/sd_bus_set_sender.xml index 512fffcf0..556e72cef 100644 --- a/man/sd_bus_set_sender.xml +++ b/man/sd_bus_set_sender.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_set_sender @@ -89,13 +90,7 @@ - - Notes - - sd_bus_set_sender() and sd_bus_get_sender() are available as - a shared library, which can be compiled and linked to with the libsystemd pkg-config1 file. - + See Also diff --git a/man/sd_bus_set_watch_bind.xml b/man/sd_bus_set_watch_bind.xml index 41a4bc27d..129b98c5f 100644 --- a/man/sd_bus_set_watch_bind.xml +++ b/man/sd_bus_set_watch_bind.xml @@ -6,7 +6,8 @@ SPDX-License-Identifier: LGPL-2.1+ --> - + sd_bus_set_watch_bind @@ -100,13 +101,7 @@ - - Notes - - sd_bus_set_watch_bind() and sd_bus_get_watch_bind() are available as - a shared library, which can be compiled and linked to with the libsystemd pkg-config1 file. - + See Also -- cgit v1.2.3-65-gdbad