From 0eea10301708c64a6b793894c156e21ddd15eb64 Mon Sep 17 00:00:00 2001 From: Balbir Singh Date: Thu, 7 Feb 2008 00:13:57 -0800 Subject: Memory controller improve user interface Change the interface to use bytes instead of pages. Page sizes can vary across platforms and configurations. A new strategy routine has been added to the resource counters infrastructure to format the data as desired. Suggested by David Rientjes, Andrew Morton and Herbert Poetzl Tested on a UML setup with the config for memory control enabled. [kamezawa.hiroyu@jp.fujitsu.com: possible race fix in res_counter] Signed-off-by: Balbir Singh Signed-off-by: Pavel Emelianov Cc: Paul Menage Cc: Peter Zijlstra Cc: "Eric W. Biederman" Cc: Nick Piggin Cc: Kirill Korotaev Cc: Herbert Poetzl Cc: David Rientjes Cc: Vaidyanathan Srinivasan Signed-off-by: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/res_counter.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-) (limited to 'kernel') diff --git a/kernel/res_counter.c b/kernel/res_counter.c index 722c484b068..16cbec2d5d6 100644 --- a/kernel/res_counter.c +++ b/kernel/res_counter.c @@ -16,7 +16,7 @@ void res_counter_init(struct res_counter *counter) { spin_lock_init(&counter->lock); - counter->limit = (unsigned long)LONG_MAX; + counter->limit = (unsigned long long)LLONG_MAX; } int res_counter_charge_locked(struct res_counter *counter, unsigned long val) @@ -59,8 +59,8 @@ void res_counter_uncharge(struct res_counter *counter, unsigned long val) } -static inline unsigned long *res_counter_member(struct res_counter *counter, - int member) +static inline unsigned long long * +res_counter_member(struct res_counter *counter, int member) { switch (member) { case RES_USAGE: @@ -76,24 +76,30 @@ static inline unsigned long *res_counter_member(struct res_counter *counter, } ssize_t res_counter_read(struct res_counter *counter, int member, - const char __user *userbuf, size_t nbytes, loff_t *pos) + const char __user *userbuf, size_t nbytes, loff_t *pos, + int (*read_strategy)(unsigned long long val, char *st_buf)) { - unsigned long *val; + unsigned long long *val; char buf[64], *s; s = buf; val = res_counter_member(counter, member); - s += sprintf(s, "%lu\n", *val); + if (read_strategy) + s += read_strategy(*val, s); + else + s += sprintf(s, "%llu\n", *val); return simple_read_from_buffer((void __user *)userbuf, nbytes, pos, buf, s - buf); } ssize_t res_counter_write(struct res_counter *counter, int member, - const char __user *userbuf, size_t nbytes, loff_t *pos) + const char __user *userbuf, size_t nbytes, loff_t *pos, + int (*write_strategy)(char *st_buf, unsigned long long *val)) { int ret; char *buf, *end; - unsigned long tmp, *val; + unsigned long flags; + unsigned long long tmp, *val; buf = kmalloc(nbytes + 1, GFP_KERNEL); ret = -ENOMEM; @@ -106,12 +112,20 @@ ssize_t res_counter_write(struct res_counter *counter, int member, goto out_free; ret = -EINVAL; - tmp = simple_strtoul(buf, &end, 10); - if (*end != '\0') - goto out_free; + if (write_strategy) { + if (write_strategy(buf, &tmp)) { + goto out_free; + } + } else { + tmp = simple_strtoull(buf, &end, 10); + if (*end != '\0') + goto out_free; + } + spin_lock_irqsave(&counter->lock, flags); val = res_counter_member(counter, member); *val = tmp; + spin_unlock_irqrestore(&counter->lock, flags); ret = nbytes; out_free: kfree(buf); -- cgit v1.2.3