Implement triggers for control groups.

PATCH In review Pavel Emelyanov 3 participants 6 messages Mar 13, 2008 – Mar 14, 2008 2 messages not in the archive

Subsystems (3)

Memory management cgroup memcg

lore

Share & tools

lore

Pavel Emelyanov

author

2008-03-13 11:34 UTC #0 lore raw

cover Implement triggers for control groups.

Hi, guys.

This is the final set I'm going to send to Andrew. It has a new feature - fail counter reset - and splitted, so I send it for a final review (maybe some Acked-by-s ;) ) before sending to Andrew.

Signed-off-by Pavel Emelyanov <[email protected]>

A message that is not in the archive (sent off-list or not yet received): [email protected]

Pavel Emelyanov

author

2008-03-13 11:36 UTC #2 lore raw

PATCH 1/3 Add the trigger callback to struct cftype

Trigger callback can be used to receive a kick-up from the user space. The string written is ignored.

The cftype->private is used for multiplexing events.

Signed-off-by Pavel Emelyanov <[email protected]>

---
 include/linux/cgroup.h |    8 ++++++++
 kernel/cgroup.c        |    4 ++++
 2 files changed, 12 insertions(+), 0 deletions(-)

include/linux/cgroup.h +8 -0

index 785a01c..2d1d151 100644
@@ -243,6 +243,14 @@ struct cftype {
 	 */
 	int (*write_s64) (struct cgroup *cgrp, struct cftype *cft, s64 val);
 
+	/*
+	 * trigger() callback can be used to get some kick from the
+	 * userspace, when the actual string written is not important
+	 * at all. The private field can be used to determine the
+	 * kick type for multiplexing.
+	 */
+	int (*trigger)(struct cgroup *cgrp, unsigned int event);
+
 	int (*release) (struct inode *inode, struct file *file);
 };

kernel/cgroup.c +4 -0

index e8e8ec4..f2d8f25 100644
@@ -1410,6 +1410,10 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf,
 		return cft->write(cgrp, cft, file, buf, nbytes, ppos);
 	if (cft->write_u64 || cft->write_s64)
 		return cgroup_write_X64(cgrp, cft, file, buf, nbytes, ppos);
+	if (cft->trigger) {
+		int ret = cft->trigger(cgrp, (unsigned int)cft->private);
+		return ret ? ret : nbytes;
+	}
 	return -EINVAL;
 }

Signature · 1 line

1.5.3.4

A message that is not in the archive (sent off-list or not yet received): [email protected]

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index e8e8ec4..f2d8f25 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1410,6 +1410,10 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf,

                return cft->write(cgrp, cft, file, buf, nbytes, ppos);
        if (cft->write_u64 || cft->write_s64)
                return cgroup_write_X64(cgrp, cft, file, buf, nbytes, ppos);
 +       if (cft->trigger) {
 +               int ret = cft->trigger(cgrp, (unsigned int)cft->private);
 +               return ret ? ret : nbytes;
 +       }
        return -EINVAL;

}

--
1.5.3.4

Pavel Emelyanov

author

2008-03-13 11:37 UTC #5 lore raw

PATCH 2/3 Use triggers in force_empty and max_usage files

In reply to a message not in the archive

Signed-off-by Pavel Emelyanov <[email protected]>

---
 mm/memcontrol.c |   21 ++++++---------------
 1 files changed, 6 insertions(+), 15 deletions(-)

mm/memcontrol.c +6 ~~-15~~

index c27141d..d3ec3e3 100644
@@ -868,27 +868,18 @@ static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
 				mem_cgroup_write_strategy);
 }
 
-static ssize_t mem_cgroup_max_reset(struct cgroup *cont, struct cftype *cft,
-				struct file *file, const char __user *userbuf,
-				size_t nbytes, loff_t *ppos)
+static int mem_cgroup_max_reset(struct cgroup *cont, unsigned int event)
 {
 	struct mem_cgroup *mem;
 
 	mem = mem_cgroup_from_cont(cont);
 	res_counter_reset_max(&mem->res);
-	return nbytes;
+	return 0;
 }
 
-static ssize_t mem_force_empty_write(struct cgroup *cont,
-				struct cftype *cft, struct file *file,
-				const char __user *userbuf,
-				size_t nbytes, loff_t *ppos)
+static int mem_force_empty_write(struct cgroup *cont, unsigned int event)
 {
-	struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
-	int ret = mem_cgroup_force_empty(mem);
-	if (!ret)
-		ret = nbytes;
-	return ret;
+	return mem_cgroup_force_empty(mem_cgroup_from_cont(cont));
 }
 
 static const struct mem_cgroup_stat_desc {

@@ -936,7 +927,7 @@ static struct cftype mem_cgroup_files[] = {
 	{
 		.name = "max_usage_in_bytes",
 		.private = RES_MAX_USAGE,
-		.write = mem_cgroup_max_reset,
+		.trigger = mem_cgroup_max_reset,
 		.read_u64 = mem_cgroup_read,
 	},
 	{

@@ -952,7 +943,7 @@ static struct cftype mem_cgroup_files[] = {
 	},
 	{
 		.name = "force_empty",
-		.write = mem_force_empty_write,
+		.trigger = mem_force_empty_write,
 	},
 	{
 		.name = "stat",

Signature · 1 line

1.5.3.4

Pavel Emelyanov

author

2008-03-13 11:39 UTC #6 lore raw

PATCH 3/3 Implement failcounter reset

In reply to a message not in the archive

Merge two resets into one mem_cgroup_reset() function to demonstrate how multiplexing work.

Besides, I have plans to move the files, that correspond to res_counter to the res_counter.c file and somehow "import" them into controller. I don't know how to make it gracefully yet, but merging resets of max_usage and failcnt in one function will be there for sure.

Signed-off-by Pavel Emelyanov <[email protected]>

---
 include/linux/res_counter.h |    8 ++++++++
 mm/memcontrol.c             |   14 +++++++++++---
 2 files changed, 19 insertions(+), 3 deletions(-)

include/linux/res_counter.h +8 -0

index df8085a..3c05d6d 100644
@@ -141,4 +141,12 @@ static inline void res_counter_reset_max(struct res_counter *cnt)
 	spin_unlock_irqrestore(&cnt->lock, flags);
 }
 
+static inline void res_counter_reset_failcnt(struct res_counter *cnt)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cnt->lock, flags);
+	cnt->failcnt = 0;
+	spin_unlock_irqrestore(&cnt->lock, flags);
+}
 #endif

mm/memcontrol.c +11 -3

index d3ec3e3..5852b23 100644
@@ -868,12 +868,19 @@ static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
 				mem_cgroup_write_strategy);
 }
 
-static int mem_cgroup_max_reset(struct cgroup *cont, unsigned int event)
+static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
 {
 	struct mem_cgroup *mem;
 
 	mem = mem_cgroup_from_cont(cont);
-	res_counter_reset_max(&mem->res);
+	switch (event) {
+		case RES_MAX_USAGE:
+			res_counter_reset_max(&mem->res);
+			break;
+		case RES_FAILCNT:
+			res_counter_reset_failcnt(&mem->res);
+			break;
+	}
 	return 0;
 }

@@ -927,7 +934,7 @@ static struct cftype mem_cgroup_files[] = {
 	{
 		.name = "max_usage_in_bytes",
 		.private = RES_MAX_USAGE,
-		.trigger = mem_cgroup_max_reset,
+		.trigger = mem_cgroup_reset,
 		.read_u64 = mem_cgroup_read,
 	},
 	{

@@ -939,6 +946,7 @@ static struct cftype mem_cgroup_files[] = {
 	{
 		.name = "failcnt",
 		.private = RES_FAILCNT,
+		.trigger = mem_cgroup_reset,
 		.read_u64 = mem_cgroup_read,
 	},
 	{

Signature · 1 line

1.5.3.4

KAMEZAWA Hiroyuki

Acked-by

2008-03-14 02:08 UTC #7 lore raw

In reply to a message not in the archive

Quoted 7 lines · On Thu, 13 Mar 2008 14:34:39 +0300 Pavel Emelyanov…

Hi, guys.
This is the final set I'm going to send to Andrew. It has a new feature - fail counter reset - and splitted, so I send it for a final review (maybe some Acked-by-s ;) ) before sending to Andrew.
Signed-off-by Pavel Emelyanov <[email protected]>

I like this new interface. thank you.

Acked-by KAMEZAWA Hiroyuki <[email protected]>