mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

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: Brad Boyer <flar@allandria.com>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/71ed7fb234a5f7381a50253b0d841a656d53e64c.1684200125.git.fthain@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This commit is contained in:
Finn Thain 2023-05-16 11:22:05 +10:00 committed by Geert Uytterhoeven
parent b7629ce6f4
commit 72b44f6577
3 changed files with 15 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/nubus/nubus.c
View File

@ -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);
}
}

8
drivers/nubus/proc.c
View File

@ -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);

1
include/linux/nubus.h
View File

@ -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,