5/6: ckrm_numtasks_forkrate
Adds support to control the forkrate in the system.
--
Signed-Off-By: Chandra Seetharaman <[email protected]>
Signed-Off-By: Matt Helsley <[email protected]>
kernel/ckrm/ckrm_numtasks.c | 75 ++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 75 insertions(+)
Index: linux2617-rc2/kernel/ckrm/ckrm_numtasks.c
===================================================================
--- linux2617-rc2.orig/kernel/ckrm/ckrm_numtasks.c
+++ linux2617-rc2/kernel/ckrm/ckrm_numtasks.c
@@ -27,6 +27,11 @@ static int total_numtasks __read_mostly
static struct ckrm_class *root_class;
static int total_cnt_alloc = 0;
+#define DEF_FORKRATE UNLIMITED
+#define DEF_FORKRATE_INTERVAL (1)
+static int forkrate __read_mostly = DEF_FORKRATE;
+static int forkrate_interval __read_mostly = DEF_FORKRATE_INTERVAL;
+
struct ckrm_numtasks {
struct ckrm_class *class; /* the class i am part of... */
struct ckrm_shares shares;
@@ -41,6 +46,11 @@ struct ckrm_numtasks {
/* stats */
int successes;
int failures;
+ int forkrate_failures;
+
+ /* Fork rate fields */
+ int forks_in_period;
+ unsigned long period_start;
};
struct ckrm_controller numtasks_ctlr;
@@ -58,8 +68,24 @@ static struct ckrm_numtasks *get_class_n
&numtasks_ctlr));
}
+static inline int check_forkrate(struct ckrm_numtasks *res)
+{
+ if (time_after(jiffies, res->period_start + forkrate_interval * HZ)) {
+ res->period_start = jiffies;
+ res->forks_in_period = 0;
+ }
+
+ if (res->forks_in_period >= forkrate) {
+ res->forkrate_failures++;
+ return -ENOSPC;
+ }
+ res->forks_in_period++;
+ return 0;
+}
+
int numtasks_allow_fork(struct ckrm_class *class)
{
+ int rc;
struct ckrm_numtasks *res;
/* controller is not registered; no class is given */
@@ -71,6 +97,11 @@ int numtasks_allow_fork(struct ckrm_clas
if (!res)
return 0;
+ /* Check forkrate before checking class's usage */
+ rc = check_forkrate(res);
+ if (rc)
+ return rc;
+
if (res->cnt_max_shares == CKRM_SHARE_DONT_CARE)
return 0;
@@ -146,6 +177,7 @@ static void numtasks_res_init_one(struct
numtasks_res->cnt_min_shares = CKRM_SHARE_DONT_CARE;
numtasks_res->cnt_unused = CKRM_SHARE_DONT_CARE;
numtasks_res->cnt_max_shares = CKRM_SHARE_DONT_CARE;
+ numtasks_res->period_start = jiffies;
}
static struct ckrm_shares *numtasks_alloc_shares_struct(
@@ -306,6 +338,9 @@ static ssize_t numtasks_show_stats(struc
buf += i; j += i; buf_size -= i;
i = snprintf(buf, buf_size, "%s: Number of failures %d\n",
res_ctlr_name, res->failures);
+ buf += i; j += i; buf_size -= i;
+ i = snprintf(buf, buf_size, "%s: Number of forkrate failures %d\n",
+ res_ctlr_name, res->forkrate_failures);
j += i;
return j;
}
@@ -365,6 +400,46 @@ static int set_total_numtasks(const char
module_param_set_call(total_numtasks, int, set_total_numtasks,
S_IRUGO | S_IWUSR);
+static void reset_forkrates(struct ckrm_class *class, unsigned long now)
+{
+ struct ckrm_numtasks *res;
+ struct ckrm_class *child = NULL;
+
+ res = get_class_numtasks(class);
+ if (!res)
+ return;
+ res->forks_in_period = 0;
+ res->period_start = now;
+
+ spin_lock(&class->class_lock);
+ for_each_child(child, class)
+ reset_forkrates(child, now);
+ spin_unlock(&class->class_lock);
+}
+
+static int set_forkrate(const char *val, struct kernel_param *kp)
+{
+ int prev = forkrate;
+ int rc = set_numtasks_config_val(&forkrate, prev, val, kp);
+ if (rc < 0)
+ return rc;
+ reset_forkrates(root_class, jiffies);
+ return 0;
+}
+module_param_set_call(forkrate, int, set_forkrate, S_IRUGO | S_IWUSR);
+
+static int set_forkrate_interval(const char *val, struct kernel_param *kp)
+{
+ int prev = forkrate_interval;
+ int rc = set_numtasks_config_val(&forkrate_interval, prev, val, kp);
+ if (rc < 0)
+ return rc;
+ reset_forkrates(root_class, jiffies);
+ return 0;
+}
+module_param_set_call(forkrate_interval, int, set_forkrate_interval,
+ S_IRUGO | S_IWUSR);
+
int __init init_ckrm_numtasks_res(void)
{
if (numtasks_ctlr.ctlr_id != CKRM_NO_RES_ID)
--
----------------------------------------------------------------------
Chandra Seetharaman | Be careful what you choose....
- [email protected] | .......you may get it.
----------------------------------------------------------------------
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
