Commit 72b44f65 authored by Finn Thain's avatar Finn Thain Committed by Geert Uytterhoeven
Browse files

nubus: Don't list slot resources by default 



Some Nubus card ROMs contain many slot resources. A single Radius video
card produced well over a thousand entries under /proc/bus/nubus/.
Populating /proc/bus/nubus/ on a slow machine with several such cards
installed takes long enough that the user may think that the system is
wedged. All those procfs entries also consume significant RAM though
they are not normally needed (except by developers).
Omit these resources from /proc/bus/nubus/ by default and add a kernel
parameter to enable them when needed.
On the test machine, this saved 300 kB and 10 seconds.

Cc: Brad Boyer <flar@allandria.com>
Reviewed-by: default avatarBrad Boyer <flar@allandria.com>
Tested-by: default avatarStan Johnson <userm57@yahoo.com>
Signed-off-by: default avatarFinn Thain <fthain@linux-m68k.org>
Reviewed-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/71ed7fb234a5f7381a50253b0d841a656d53e64c.1684200125.git.fthain@linux-m68k.org


Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
parent b7629ce6

drivers/nubus/nubus.c

+10 −3
Original line number Diff line number Diff line
@@ -32,6 +32,13 @@ 


/* Globals */



/* The "nubus.populate_procfs" parameter makes slot resources available in

 * procfs. It's deprecated and disabled by default because procfs is no longer

 * thought to be suitable for that and some board ROMs make it too expensive.

 */

bool nubus_populate_procfs;

module_param_named(populate_procfs, nubus_populate_procfs, bool, 0);



LIST_HEAD(nubus_func_rsrcs);



/* Meaning of "bytelanes":
@@ -572,9 +579,9 @@ nubus_get_functional_resource(struct nubus_board *board, int slot, 
			nubus_proc_add_rsrc(dir.procdir, &ent);

			break;

		default:

			/* Local/Private resources have their own

			   function */

			nubus_get_private_resource(fres, dir.procdir, &ent);

			if (nubus_populate_procfs)

				nubus_get_private_resource(fres, dir.procdir,

							   &ent);

		}

	}

drivers/nubus/proc.c

+4 −4
Original line number Diff line number Diff line
@@ -55,7 +55,7 @@ struct proc_dir_entry *nubus_proc_add_board(struct nubus_board *board) 
{

	char name[2];



	if (!proc_bus_nubus_dir)

	if (!proc_bus_nubus_dir || !nubus_populate_procfs)

		return NULL;

	snprintf(name, sizeof(name), "%x", board->slot);

	return proc_mkdir(name, proc_bus_nubus_dir);
@@ -72,7 +72,7 @@ struct proc_dir_entry *nubus_proc_add_rsrc_dir(struct proc_dir_entry *procdir, 
	char name[9];

	int lanes = board->lanes;



	if (!procdir)

	if (!procdir || !nubus_populate_procfs)

		return NULL;

	snprintf(name, sizeof(name), "%x", ent->type);

	remove_proc_subtree(name, procdir);
@@ -157,7 +157,7 @@ void nubus_proc_add_rsrc_mem(struct proc_dir_entry *procdir, 
	char name[9];

	struct nubus_proc_pde_data *pded;



	if (!procdir)

	if (!procdir || !nubus_populate_procfs)

		return;



	snprintf(name, sizeof(name), "%x", ent->type);
@@ -176,7 +176,7 @@ void nubus_proc_add_rsrc(struct proc_dir_entry *procdir, 
	char name[9];

	unsigned char *data = (unsigned char *)ent->data;



	if (!procdir)

	if (!procdir || !nubus_populate_procfs)

		return;



	snprintf(name, sizeof(name), "%x", ent->type);

include/linux/nubus.h

+1 −0
Original line number Diff line number Diff line
@@ -93,6 +93,7 @@ extern struct bus_type nubus_bus_type; 


/* Generic NuBus interface functions, modelled after the PCI interface */

#ifdef CONFIG_PROC_FS

extern bool nubus_populate_procfs;

void nubus_proc_init(void);

struct proc_dir_entry *nubus_proc_add_board(struct nubus_board *board);

struct proc_dir_entry *nubus_proc_add_rsrc_dir(struct proc_dir_entry *procdir,