(no subject)

[Martin Nicolay]

From 7f5bb47a3b5b7a5443009078d936ab62dfa1fd85 Mon Sep 17 00:00:00 2001
From: Martin Nicolay <m.nicolay@osm-ag.de>
Date: Fri, 15 Nov 2019 16:41:20 +0100
Subject: [PATCH] enable a timeout for hold_lock_file_for_update

The new funktion get_files_lock_timeout_ms reads the config
core.fileslocktimeout analog get_files_ref_lock_timeout_ms.

This value is used in hold_lock_file_for_update instead of the
fixed value 0.
---
While working with complex scripts invoking git multiple times my
editor detects the changes and calls "git status". This leads to
aborts in "git-stash". With this patch and an appropriate value
core.fileslocktimeout this problem goes away.

 lockfile.c | 15 +++++++++++++++
 lockfile.h |  4 +++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/lockfile.c b/lockfile.c
index 8e8ab4f29f..ac19de8937 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -145,6 +145,21 @@ static int lock_file_timeout(struct lock_file *lk, const char *path,
 	}
 }
 
+long get_files_lock_timeout_ms(void)
+{
+	static int configured = 0;
+
+	/* The default timeout is 100 ms: */
+	static int timeout_ms = 100;
+
+	if (!configured) {
+		git_config_get_int("core.fileslocktimeout", &timeout_ms);
+		configured = 1;
+	}
+
+	return timeout_ms;
+}
+
 void unable_to_lock_message(const char *path, int err, struct strbuf *buf)
 {
 	if (err == EEXIST) {
diff --git a/lockfile.h b/lockfile.h
index 9843053ce8..a0520e6a7b 100644
--- a/lockfile.h
+++ b/lockfile.h
@@ -163,6 +163,8 @@ int hold_lock_file_for_update_timeout(
 		struct lock_file *lk, const char *path,
 		int flags, long timeout_ms);
 
+long get_files_lock_timeout_ms(void);
+
 /*
  * Attempt to create a lockfile for the file at `path` and return a
  * file descriptor for writing to it, or -1 on error. The flags
@@ -172,7 +174,7 @@ static inline int hold_lock_file_for_update(
 		struct lock_file *lk, const char *path,
 		int flags)
 {
-	return hold_lock_file_for_update_timeout(lk, path, flags, 0);
+	return hold_lock_file_for_update_timeout(lk, path, flags, get_files_lock_timeout_ms() );
 }
 
 /*
-- 
2.13.7

Re:

[Martin Ågren]

Hi Martin

On Fri, 15 Nov 2019 at 17:17, Martin Nicolay <martin@wsmn.osm-gmbh.de> wrote:

> While working with complex scripts invoking git multiple times my
> editor detects the changes and calls "git status". This leads to
> aborts in "git-stash". With this patch and an appropriate value
> core.fileslocktimeout this problem goes away.

Are you able to patch your editor to call
  git --no-optional-locks status
instead? See the bottom of git-status(1) ("BACKGROUND REFRESH") for more
on this.

> +long get_files_lock_timeout_ms(void)
> +{
> +       static int configured = 0;
> +
> +       /* The default timeout is 100 ms: */
> +       static int timeout_ms = 100;
> +
> +       if (!configured) {
> +               git_config_get_int("core.fileslocktimeout", &timeout_ms);
> +               configured = 1;
> +       }
> +
> +       return timeout_ms;
> +}
> +

> @@ -172,7 +174,7 @@ static inline int hold_lock_file_for_update(
>                 struct lock_file *lk, const char *path,
>                 int flags)
>  {
> -       return hold_lock_file_for_update_timeout(lk, path, flags, 0);
> +       return hold_lock_file_for_update_timeout(lk, path, flags, get_files_lock_timeout_ms() );
>  }

This looks like it changes the default from 0 ("try exactly once") to
100ms. Maybe we should stick with 0 for those who don't jump onto this
new config knob?

Martin

Re:

[Martin Ågren]

[Trying with another e-mail address for Martin Nicolay. Maybe the one
from the in-body From header works better. wsmn.osm-gmbh.de couldn't be
found.]

On Fri, 15 Nov 2019 at 17:29, Martin Ågren <martin.agren@gmail.com> wrote:
>
> Hi Martin
>
> On Fri, 15 Nov 2019 at 17:17, Martin Nicolay <martin@wsmn.osm-gmbh.de> wrote:
>
> > While working with complex scripts invoking git multiple times my
> > editor detects the changes and calls "git status". This leads to
> > aborts in "git-stash". With this patch and an appropriate value
> > core.fileslocktimeout this problem goes away.
>
> Are you able to patch your editor to call
>   git --no-optional-locks status
> instead? See the bottom of git-status(1) ("BACKGROUND REFRESH") for more
> on this.
>
> > +long get_files_lock_timeout_ms(void)
> > +{
> > +       static int configured = 0;
> > +
> > +       /* The default timeout is 100 ms: */
> > +       static int timeout_ms = 100;
> > +
> > +       if (!configured) {
> > +               git_config_get_int("core.fileslocktimeout", &timeout_ms);
> > +               configured = 1;
> > +       }
> > +
> > +       return timeout_ms;
> > +}
> > +
>
> > @@ -172,7 +174,7 @@ static inline int hold_lock_file_for_update(
> >                 struct lock_file *lk, const char *path,
> >                 int flags)
> >  {
> > -       return hold_lock_file_for_update_timeout(lk, path, flags, 0);
> > +       return hold_lock_file_for_update_timeout(lk, path, flags, get_files_lock_timeout_ms() );
> >  }
>
> This looks like it changes the default from 0 ("try exactly once") to
> 100ms. Maybe we should stick with 0 for those who don't jump onto this
> new config knob?
>
> Martin