code: plan9front

Info  •  Files  •  Log

libc: Add poolreset() function

This is intended for the secrmem pool in the kernel,
but could also be used for temporary pools to
recover the memory used by the arenas.

--- a/sys/include/pool.h

+++ b/sys/include/pool.h

@@ -17,6 +17,7 @@

 	void*	(*alloc)(ulong);

 	int	(*merge)(void*, void*);

 	void	(*move)(void* from, void* to);

+	void	(*free)(void*, ulong);

 	int	flags;

 	int	nfree;

@@ -36,6 +37,7 @@

 extern void	poolfree(Pool*, void*);

 extern ulong	poolmsize(Pool*, void*);

 extern int	poolisoverlap(Pool*, void*, ulong);

+extern void	poolreset(Pool*);

 extern void*	poolrealloc(Pool*, void*, ulong);

 extern void	poolcheck(Pool*);

 extern int	poolcompact(Pool*);

--- a/sys/man/2/pool

+++ b/sys/man/2/pool

@@ -28,6 +28,9 @@

 int	poolisoverlap(Pool* pool, void* ptr, ulong len)

 .PP

 .B

+void	poolreset(Pool* pool)

+.PP

+.B

 void*	poolrealloc(Pool* pool, void* ptr, ulong size)

 .PP

 .B

@@ -119,6 +122,18 @@

 .BR pool ,

 returning non-zero when there is overlap or zero if none.

 .PP

+.I Poolreset

+clears the pool counters and frees all arenas.

+The arenas are filled with a pattern before

+freeing them when the

+.B POOL_ANTAGONISM

+flag is set.

+When the

+.B free

+function of the pool is non-nil,

+it is called for each arena,

+passing its pointer and size.

+.PP

 The 

 .I poolblockcheck

 and

@@ -156,6 +171,7 @@

 	void*	(*alloc)(ulong);

 	int	(*merge)(void*, void*);

 	void	(*move)(void* from, void* to);

+	void	(*free)(void*, ulong);

 	void	(*lock)(Pool*);

 	void	(*unlock)(Pool*);

 	void	(*print)(Pool*, char*, ...);

@@ -279,12 +295,15 @@

 with a constant.

 The pointer value is the pointer to the beginning of the allocated block

 and the constant varies in order to distinguish different markings.

-Freed blocks use the constant 

+Freed blocks use the constant

 .BR 0xF7000000 ,

 newly allocated blocks

 .BR 0xF9000000 ,

 and newly created unallocated blocks

-.BR 0xF1000000 .

+.BR 0xF1000000 ,

+freed arenas after

+.I poolreset

+.BR 0xFF000000 .

 For example, if 

 .B POOL_ANTAGONISM 

 is set and

--- a/sys/src/libc/port/mkfile

+++ b/sys/src/libc/port/mkfile

@@ -131,6 +131,8 @@

 profile.$O: /sys/include/tos.h

+malloc.$O pool.$O: /sys/include/pool.h

+

 runenorm.$O:	runenormdata runenorm.c

 runetotype.$O:	runetotypedata runetotype.c

 runeistype.$O:	runeistypedata runeistype.c

--- a/sys/src/libc/port/pool.c

+++ b/sys/src/libc/port/pool.c

@@ -1345,6 +1345,43 @@

 	return a != nil;

 }

+void

+poolreset(Pool *p)

+{

+	Arena *a;

+

+	if(p == nil)

+		return;

+

+	p->lock(p);

+	paranoia {

+		poolcheckl(p);

+	}

+	verbosity {

+		pooldumpl(p);

+	}

+	p->cursize = 0;

+	p->curfree = 0;

+	p->curalloc = 0;

+	p->lastcompact = p->nfree = 0;

+	p->freeroot = nil;

+	a = p->arenalist;

+	p->arenalist = nil;

+	LOG(p, "poolreset %p\n", p);

+	p->unlock(p);

+

+	while(a != nil){

+		Arena *next = a->down;

+		ulong asize = a->asize;

+		antagonism {

+			memmark(a, 0xFF, asize);

+		}

+		if(p->free)

+			p->free(a, asize);

+		a = next;

+	}

+}

+

 /*

  * Debugging

  */

--- a/sys/src/libmemdraw/mkfile

+++ b/sys/src/libmemdraw/mkfile

@@ -29,6 +29,8 @@

 </sys/src/cmd/mksyslib

+alloc.$O draw.$O: /sys/include/pool.h

+

 $O.drawtest: drawtest.$O $LIB

 	$LD -o $target $prereq