Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8eab945c authored by Artem Bityutskiy's avatar Artem Bityutskiy Committed by J. Bruce Fields
Browse files

sunrpc: make the cache cleaner workqueue deferrable 



This patch makes the cache_cleaner workqueue deferrable, to prevent
unnecessary system wake-ups, which is very important for embedded
battery-powered devices.

do_cache_clean() is called every 30 seconds at the moment, and often
makes the system wake up from its power-save sleep state. With this
change, when the workqueue uses a deferrable timer, the
do_cache_clean() invocation will be delayed and combined with the
closest "real" wake-up. This improves the power consumption situation.

Note, I tried to create a DECLARE_DELAYED_WORK_DEFERRABLE() helper
macro, similar to DECLARE_DELAYED_WORK(), but failed because of the
way the timer wheel core stores the deferrable flag (it is the
LSBit in the time->base pointer). My attempt to define a static
variable with this bit set ended up with the "initializer element is
not constant" error.

Thus, I have to use run-time initialization, so I created a new
cache_initialize() function which is called once when sunrpc is
being initialized.

Signed-off-by: default avatarArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
parent cba9ba4b

include/linux/sunrpc/cache.h

+1 −0
Original line number Diff line number Diff line
@@ -192,6 +192,7 @@ extern int cache_check(struct cache_detail *detail, 
extern void cache_flush(void);

extern void cache_purge(struct cache_detail *detail);

#define NEVER (0x7FFFFFFF)

extern void __init cache_initialize(void);

extern int cache_register(struct cache_detail *cd);

extern void cache_unregister(struct cache_detail *cd);

net/sunrpc/cache.c

+6 −1
Original line number Diff line number Diff line
@@ -320,7 +320,7 @@ static struct cache_detail *current_detail; 
static int current_index;



static void do_cache_clean(struct work_struct *work);

static DECLARE_DELAYED_WORK(cache_cleaner, do_cache_clean);

static struct delayed_work cache_cleaner;



static void sunrpc_init_cache_detail(struct cache_detail *cd)

{
@@ -1504,6 +1504,11 @@ static int create_cache_proc_entries(struct cache_detail *cd) 
}

#endif



void __init cache_initialize(void)

{

	INIT_DELAYED_WORK_DEFERRABLE(&cache_cleaner, do_cache_clean);

}



int cache_register(struct cache_detail *cd)

{

	int ret;

net/sunrpc/sunrpc_syms.c

+1 −0
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ init_sunrpc(void) 
#ifdef CONFIG_PROC_FS

	rpc_proc_init();

#endif

	cache_initialize();

	cache_register(&ip_map_cache);

	cache_register(&unix_gid_cache);

	svc_init_xprt_sock();	/* svc sock transport */