Make reserved be an option when mounting a hugetlbfs. reserved option is only possible if size option is also specified. On mount, reserve size hugepages and note in subpool. Unreserve pages when fs is unmounted.
Signed-off-by: Mike Kravetz <[email protected]> --- fs/hugetlbfs/inode.c | 15 +++++++++++++-- include/linux/hugetlb.h | 1 + mm/hugetlb.c | 15 ++++++++++++++- 3 files changed, 28 insertions(+), 3 deletions(-) diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 5eba47f..99d0cec 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -50,6 +50,7 @@ struct hugetlbfs_config { long nr_blocks; long nr_inodes; struct hstate *hstate; + bool reserved; }; struct hugetlbfs_inode_info { @@ -73,7 +74,7 @@ int sysctl_hugetlb_shm_group; enum { Opt_size, Opt_nr_inodes, Opt_mode, Opt_uid, Opt_gid, - Opt_pagesize, + Opt_pagesize, Opt_reserved, Opt_err, }; @@ -84,6 +85,7 @@ static const match_table_t tokens = { {Opt_uid, "uid=%u"}, {Opt_gid, "gid=%u"}, {Opt_pagesize, "pagesize=%s"}, + {Opt_reserved, "reserved"}, {Opt_err, NULL}, }; @@ -832,6 +834,10 @@ hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) break; } + case Opt_reserved: + pconfig->reserved = true; + break; + default: pr_err("Bad mount option: \"%s\"\n", p); return -EINVAL; @@ -872,6 +878,7 @@ hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) config.gid = current_fsgid(); config.mode = 0755; config.hstate = &default_hstate; + config.reserved = false; ret = hugetlbfs_parse_options(data, &config); if (ret) return ret; @@ -889,7 +896,11 @@ hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) sbinfo->spool = hugepage_new_subpool(config.nr_blocks); if (!sbinfo->spool) goto out_free; - } + sbinfo->spool->hstate = config.hstate; + if (config.reserved && !reserve_hugepage_subpool(sbinfo->spool)) + goto out_free; + } else if (config.reserved) + goto out_free; sb->s_maxbytes = MAX_LFS_FILESIZE; sb->s_blocksize = huge_page_size(config.hstate); sb->s_blocksize_bits = huge_page_shift(config.hstate); diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 605c648..117e1bd 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -45,6 +45,7 @@ static inline bool subpool_reserved(struct hugepage_subpool *spool) return spool && spool->reserved; } struct hugepage_subpool *hugepage_new_subpool(long nr_blocks); +bool reserve_hugepage_subpool(struct hugepage_subpool *spool); void hugepage_put_subpool(struct hugepage_subpool *spool); int PageHuge(struct page *page); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 4ef8379..3ae3596 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -61,6 +61,8 @@ DEFINE_SPINLOCK(hugetlb_lock); static int num_fault_mutexes; static struct mutex *htlb_fault_mutex_table ____cacheline_aligned_in_smp; +/* Forward declaration */ +static int hugetlb_acct_memory(struct hstate *h, long delta); static inline void unlock_or_release_subpool(struct hugepage_subpool *spool) { bool free = (spool->count == 0) && (spool->used_hpages == 0); @@ -69,8 +71,11 @@ static inline void unlock_or_release_subpool(struct hugepage_subpool *spool) /* If no pages are used, and no other handles to the subpool * remain, free the subpool the subpool remain */ - if (free) + if (free) { + if (spool->reserved) + hugetlb_acct_memory(spool->hstate, -spool->max_hpages); kfree(spool); + } } struct hugepage_subpool *hugepage_new_subpool(long nr_blocks) @@ -91,6 +96,14 @@ struct hugepage_subpool *hugepage_new_subpool(long nr_blocks) return spool; } +bool reserve_hugepage_subpool(struct hugepage_subpool *spool) +{ + if (hugetlb_acct_memory(spool->hstate, spool->max_hpages)) + return false; + spool->reserved = true; + return true; +} + void hugepage_put_subpool(struct hugepage_subpool *spool) { spin_lock(&spool->lock); -- 2.1.0 -- 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/
