PR/57208 CVS commit: src/sys/kern

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

The following reply was made to PR kern/57208; it has been noted by GNATS.

From: "Taylor R Campbell" <riastradh%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/57208 CVS commit: src/sys/kern
Date: Tue, 17 Oct 2023 11:57:20 +0000

 Module Name:	src
 Committed By:	riastradh
 Date:		Tue Oct 17 11:57:20 UTC 2023
 
 Modified Files:
 	src/sys/kern: subr_thmap.c
 
 Log Message:
 thmap(9): Preallocate GC list storage for thmap_del.
 
 thmap_del can't fail, and it is used in places in npf where sleeping
 is forbidden, so it can't rely on allocating memory either.
 
 Instead of having thmap_del allocate memory on the fly for each
 object to defer freeing until thmap_gc, arrange to have thmap(9)
 preallocate the same storage when allocating all the objects in the
 first place, with a GC header.
 
 This is suboptimal for memory usage, especially on insertion- and
 lookup-heavy but deletion-light workloads, but it's not clear rmind's
 alternative (https://github.com/rmind/thmap/tree/thmap_del_mem_fail)
 is ready to use yet, so we'll go with this for correctness.
 
 PR kern/57208
 https://github.com/rmind/npf/issues/129
 
 XXX pullup-10
 XXX pullup-9
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.14 -r1.15 src/sys/kern/subr_thmap.c
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.