From 9cfe015aa424b3c003baba3841a60dd9b5ad319b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 6 Feb 2008 01:37:16 -0800 Subject: get rid of NR_OPEN and introduce a sysctl_nr_open NR_OPEN (historically set to 1024*1024) actually forbids processes to open more than 1024*1024 handles. Unfortunatly some production servers hit the not so 'ridiculously high value' of 1024*1024 file descriptors per process. Changing NR_OPEN is not considered safe because of vmalloc space potential exhaust. This patch introduces a new sysctl (/proc/sys/fs/nr_open) wich defaults to 1024*1024, so that admins can decide to change this limit if their workload needs it. [akpm@linux-foundation.org: export it for sparc64] Signed-off-by: Eric Dumazet Cc: Alan Cox Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: "David S. Miller" Cc: Ralf Baechle Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/file.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'fs') diff --git a/fs/file.c b/fs/file.c index c5575de0111..5110acb1c9e 100644 --- a/fs/file.c +++ b/fs/file.c @@ -24,6 +24,8 @@ struct fdtable_defer { struct fdtable *next; }; +int sysctl_nr_open __read_mostly = 1024*1024; + /* * We use this list to defer free fdtables that have vmalloced * sets/arrays. By keeping a per-cpu list, we avoid having to embed @@ -147,8 +149,8 @@ static struct fdtable * alloc_fdtable(unsigned int nr) nr /= (1024 / sizeof(struct file *)); nr = roundup_pow_of_two(nr + 1); nr *= (1024 / sizeof(struct file *)); - if (nr > NR_OPEN) - nr = NR_OPEN; + if (nr > sysctl_nr_open) + nr = sysctl_nr_open; fdt = kmalloc(sizeof(struct fdtable), GFP_KERNEL); if (!fdt) @@ -233,7 +235,7 @@ int expand_files(struct files_struct *files, int nr) if (nr < fdt->max_fds) return 0; /* Can we expand? */ - if (nr >= NR_OPEN) + if (nr >= sysctl_nr_open) return -EMFILE; /* All good, so we try */ -- cgit v1.2.3