[patch 08/18] hugetlb: multi hstate sysctls

[npiggin@suse.de]

[-- Attachment #1: hugetlbfs-sysctl-hstates.patch --]
[-- Type: text/plain, Size: 5157 bytes --]

Expand the hugetlbfs sysctls to handle arrays for all hstates. This
now allows the removal of global_hstate -- everything is now hstate
aware.

- I didn't bother with hugetlb_shm_group and treat_as_movable,
these are still single global.
- Also improve error propagation for the sysctl handlers a bit

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
---
 include/linux/hugetlb.h |    7 ++----
 kernel/sysctl.c         |    2 -
 mm/hugetlb.c            |   53 +++++++++++++++++++++++++++++++++++++-----------
 3 files changed, 45 insertions(+), 17 deletions(-)

Index: linux-2.6/include/linux/hugetlb.h
===================================================================
--- linux-2.6.orig/include/linux/hugetlb.h
+++ linux-2.6/include/linux/hugetlb.h
@@ -32,8 +32,6 @@ int hugetlb_fault(struct mm_struct *mm, 
 int hugetlb_reserve_pages(struct inode *inode, long from, long to);
 void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);
 
-extern unsigned long max_huge_pages;
-extern unsigned long sysctl_overcommit_huge_pages;
 extern unsigned long hugepages_treat_as_movable;
 extern const unsigned long hugetlb_zero, hugetlb_infinity;
 extern int sysctl_hugetlb_shm_group;
@@ -226,8 +224,6 @@ struct hstate *size_to_hstate(unsigned l
 
 extern struct hstate hstates[HUGE_MAX_HSTATE];
 
-#define global_hstate (hstates[0])
-
 static inline struct hstate *hstate_inode(struct inode *i)
 {
 	struct hugetlbfs_sb_info *hsb;
@@ -265,6 +261,9 @@ static inline unsigned huge_page_shift(s
 	return h->order + PAGE_SHIFT;
 }
 
+extern unsigned long max_huge_pages[HUGE_MAX_HSTATE];
+extern unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
+
 #else
 struct hstate {};
 #define hstate_file(f) NULL
Index: linux-2.6/kernel/sysctl.c
===================================================================
--- linux-2.6.orig/kernel/sysctl.c
+++ linux-2.6/kernel/sysctl.c
@@ -924,7 +924,7 @@ static struct ctl_table vm_table[] = {
 	 {
 		.procname	= "nr_hugepages",
 		.data		= &max_huge_pages,
-		.maxlen		= sizeof(unsigned long),
+		.maxlen 	= sizeof(max_huge_pages),
 		.mode		= 0644,
 		.proc_handler	= &hugetlb_sysctl_handler,
 		.extra1		= (void *)&hugetlb_zero,
Index: linux-2.6/mm/hugetlb.c
===================================================================
--- linux-2.6.orig/mm/hugetlb.c
+++ linux-2.6/mm/hugetlb.c
@@ -22,8 +22,8 @@
 #include "internal.h"
 
 const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL;
-unsigned long max_huge_pages;
-unsigned long sysctl_overcommit_huge_pages;
+unsigned long max_huge_pages[HUGE_MAX_HSTATE];
+unsigned long sysctl_overcommit_huge_pages[HUGE_MAX_HSTATE];
 static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
 unsigned long hugepages_treat_as_movable;
 
@@ -587,8 +587,16 @@ void __init huge_add_hstate(unsigned ord
 
 static int __init hugetlb_setup(char *s)
 {
-	if (sscanf(s, "%lu", &default_hstate_resv) <= 0)
-		default_hstate_resv = 0;
+	unsigned long *mhp;
+
+	if (!max_hstate)
+		mhp = &default_hstate_resv;
+	else
+		mhp = &parsed_hstate->max_huge_pages;
+
+	if (sscanf(s, "%lu", mhp) <= 0)
+		*mhp = 0;
+
 	return 1;
 }
 __setup("hugepages=", hugetlb_setup);
@@ -632,10 +640,12 @@ static inline void try_to_free_low(struc
 #endif
 
 #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
-static unsigned long set_max_huge_pages(unsigned long count)
+static unsigned long
+set_max_huge_pages(struct hstate *h, unsigned long count, int *err)
 {
 	unsigned long min_count, ret;
-	struct hstate *h = &global_hstate;
+
+	*err = 0;
 
 	/*
 	 * Increase the pool size
@@ -707,10 +717,25 @@ int hugetlb_sysctl_handler(struct ctl_ta
 			   struct file *file, void __user *buffer,
 			   size_t *length, loff_t *ppos)
 {
-	proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
-	max_huge_pages = set_max_huge_pages(max_huge_pages);
-	global_hstate.max_huge_pages = max_huge_pages;
-	return 0;
+	int err = 0;
+	struct hstate *h;
+
+	err = proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
+	if (err)
+		return err;
+
+	if (write) {
+		for_each_hstate (h) {
+			int tmp;
+
+			h->max_huge_pages = set_max_huge_pages(h,
+					max_huge_pages[h - hstates], &tmp);
+			max_huge_pages[h - hstates] = h->max_huge_pages;
+			if (tmp && !err)
+				err = tmp;
+		}
+	}
+	return err;
 }
 
 int hugetlb_treat_movable_handler(struct ctl_table *table, int write,
@@ -729,10 +754,14 @@ int hugetlb_overcommit_handler(struct ct
 			struct file *file, void __user *buffer,
 			size_t *length, loff_t *ppos)
 {
-	struct hstate *h = &global_hstate;
+	struct hstate *h;
+	int i = 0;
 	proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
 	spin_lock(&hugetlb_lock);
-	h->nr_overcommit_huge_pages = sysctl_overcommit_huge_pages;
+	for_each_hstate (h) {
+		h->nr_overcommit_huge_pages = sysctl_overcommit_huge_pages[i];
+		i++;
+	}
 	spin_unlock(&hugetlb_lock);
 	return 0;
 }

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