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| author | Cyrill Gorcunov <gorcunov@openvz.org> | 2012-12-18 01:04:57 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-18 02:15:27 +0100 |
| commit | cbac5542d48127b546a23d816380a7926eee1c25 (patch) | |
| tree | 08ae343d94b427ed971bffc507edaaade053c294 | |
| parent | procfs: add ability to plug in auxiliary fdinfo providers (diff) | |
| download | linux-cbac5542d48127b546a23d816380a7926eee1c25.tar.xz linux-cbac5542d48127b546a23d816380a7926eee1c25.zip | |
fs, eventfd: add procfs fdinfo helper
This allows us to print out raw counter value. The /proc/pid/fdinfo/fd
output is
| pos: 0
| flags: 04002
| eventfd-count: 5a
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: James Bottomley <jbottomley@parallels.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matthew Helsley <matt.helsley@gmail.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@onelan.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/eventfd.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/fs/eventfd.c b/fs/eventfd.c index d81b9f654086..35470d9b96e6 100644 --- a/fs/eventfd.c +++ b/fs/eventfd.c @@ -19,6 +19,8 @@ #include <linux/export.h> #include <linux/kref.h> #include <linux/eventfd.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> struct eventfd_ctx { struct kref kref; @@ -284,7 +286,25 @@ static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t c return res; } +#ifdef CONFIG_PROC_FS +static int eventfd_show_fdinfo(struct seq_file *m, struct file *f) +{ + struct eventfd_ctx *ctx = f->private_data; + int ret; + + spin_lock_irq(&ctx->wqh.lock); + ret = seq_printf(m, "eventfd-count: %16llx\n", + (unsigned long long)ctx->count); + spin_unlock_irq(&ctx->wqh.lock); + + return ret; +} +#endif + static const struct file_operations eventfd_fops = { +#ifdef CONFIG_PROC_FS + .show_fdinfo = eventfd_show_fdinfo, +#endif .release = eventfd_release, .poll = eventfd_poll, .read = eventfd_read, |