#include <linux/version.h>
#include <linux/lustre_lite.h>
#include <linux/lprocfs_status.h>
+#include <linux/seq_file.h>
#include "llite_internal.h"
/* /proc/lustre/llite mount point registration */
struct proc_dir_entry *proc_lustre_fs_root;
+struct file_operations llite_dump_pgcache_fops;
#ifndef LPROCFS
int lprocfs_register_mountpoint(struct proc_dir_entry *parent,
char name[MAX_STRING_SIZE + 1];
int err, id;
struct lprocfs_stats *svc_stats = NULL;
+ struct proc_dir_entry *entry;
ENTRY;
memset(lvars, 0, sizeof(lvars));
RETURN(err);
}
+ entry = create_proc_entry("dump_page_cache", 0444, sbi->ll_proc_root);
+ if (entry == NULL)
+ GOTO(out, -ENOMEM);
+ entry->proc_fops = &llite_dump_pgcache_fops;
+ entry->data = sbi;
+
svc_stats = lprocfs_alloc_stats(LPROC_LL_FILE_OPCODES);
if (svc_stats == NULL) {
err = -ENOMEM;
}
}
#undef MAX_STRING_SIZE
+
+static struct ll_async_page *llite_pglist_next_llap(struct ll_sb_info *sbi,
+ struct list_head *list)
+{
+ struct ll_async_page *llap;
+ struct list_head *pos;
+
+ list_for_each(pos, list) {
+ if (pos == &sbi->ll_pglist)
+ return NULL;
+ llap = list_entry(pos, struct ll_async_page, llap_proc_item);
+ if (llap->llap_page == NULL)
+ continue;
+ return llap;
+ }
+ LBUG();
+ return NULL;
+}
+
+#define seq_page_flag(seq, page, flag, has_flags) do { \
+ if (test_bit(PG_##flag, &(page)->flags)) { \
+ if (!has_flags) \
+ has_flags = 1; \
+ else \
+ seq_putc(seq, '|'); \
+ seq_puts(seq, #flag); \
+ } \
+ } while(0);
+
+static int llite_dump_pgcache_seq_show(struct seq_file *seq, void *v)
+{
+ struct ll_async_page *llap, *dummy_llap = seq->private;
+ struct ll_sb_info *sbi = dummy_llap->llap_cookie;
+
+ /* 2.4 doesn't seem to have SEQ_START_TOKEN, so we implement
+ * it in our own state */
+ if (dummy_llap->llap_magic == 0) {
+ seq_printf(seq, "generation | llap .cookie | page ");
+ seq_printf(seq, "inode .index [ page flags ]\n");
+ return 0;
+ }
+
+ spin_lock(&sbi->ll_pglist_lock);
+
+ llap = llite_pglist_next_llap(sbi, &dummy_llap->llap_proc_item);
+ if (llap != NULL) {
+ int has_flags = 0;
+ struct page *page = llap->llap_page;
+
+ seq_printf(seq, "%lu | %p %p | %p %p %lu [",
+ sbi->ll_pglist_gen,
+ llap, llap->llap_cookie,
+ page, page->mapping->host, page->index);
+ seq_page_flag(seq, page, locked, has_flags);
+ seq_page_flag(seq, page, error, has_flags);
+ seq_page_flag(seq, page, referenced, has_flags);
+ seq_page_flag(seq, page, uptodate, has_flags);
+ seq_page_flag(seq, page, dirty, has_flags);
+ seq_page_flag(seq, page, highmem, has_flags);
+ if (!has_flags)
+ seq_puts(seq, "-]\n");
+ else
+ seq_puts(seq, "]\n");
+ }
+
+ spin_unlock(&sbi->ll_pglist_lock);
+
+ return 0;
+}
+
+static void *llite_dump_pgcache_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct ll_async_page *llap = seq->private;
+
+ if (llap->llap_magic == 2)
+ return NULL;
+
+ return (void *)1;
+}
+
+static void *llite_dump_pgcache_seq_next(struct seq_file *seq, void *v,
+ loff_t *pos)
+{
+ struct ll_async_page *llap, *dummy_llap = seq->private;
+ struct ll_sb_info *sbi = dummy_llap->llap_cookie;
+
+ /* bail if we just displayed the banner */
+ if (dummy_llap->llap_magic == 0) {
+ dummy_llap->llap_magic = 1;
+ return dummy_llap;
+ }
+
+ /* we've just displayed the llap that is after us in the list.
+ * we advance to a position beyond it, returning null if there
+ * isn't another llap in the list beyond that new position. */
+ spin_lock(&sbi->ll_pglist_lock);
+ llap = llite_pglist_next_llap(sbi, &dummy_llap->llap_proc_item);
+ list_del_init(&dummy_llap->llap_proc_item);
+ if (llap) {
+ list_add(&dummy_llap->llap_proc_item, &llap->llap_proc_item);
+ llap = llite_pglist_next_llap(sbi, &dummy_llap->llap_proc_item);
+ }
+ spin_unlock(&sbi->ll_pglist_lock);
+
+ ++*pos;
+ if (llap == NULL) {
+ dummy_llap->llap_magic = 2;
+ return NULL;
+ }
+ return dummy_llap;
+}
+
+static void llite_dump_pgcache_seq_stop(struct seq_file *seq, void *v)
+{
+}
+
+struct seq_operations llite_dump_pgcache_seq_sops = {
+ .start = llite_dump_pgcache_seq_start,
+ .stop = llite_dump_pgcache_seq_stop,
+ .next = llite_dump_pgcache_seq_next,
+ .show = llite_dump_pgcache_seq_show,
+};
+
+/* we're displaying llaps in a list_head list. we don't want to hold a lock
+ * while we walk the entire list, and we don't want to have to seek into
+ * the right position in the list as an app advances with many syscalls. we
+ * allocate a dummy llap and hang it off file->private. its position in
+ * the list records where the app is currently displaying. this way our
+ * seq .start and .stop don't actually do anything. .next returns null
+ * when the dummy hits the end of the list which eventually leads to .release
+ * where we tear down. this kind of displaying is super-racey, so we put
+ * a generation counter on the list so the output shows when the list
+ * changes between reads.
+ */
+static int llite_dump_pgcache_seq_open(struct inode *inode, struct file *file)
+{
+ struct proc_dir_entry *dp = inode->u.generic_ip;
+ struct ll_async_page *llap;
+ struct seq_file *seq;
+ struct ll_sb_info *sbi = dp->data;
+ int rc;
+
+ llap = kmalloc(sizeof(*llap), GFP_KERNEL);
+ if (llap == NULL)
+ return -ENOMEM;
+ llap->llap_page = NULL;
+ llap->llap_cookie = sbi;
+ llap->llap_magic = 0;
+
+ rc = seq_open(file, &llite_dump_pgcache_seq_sops);
+ if (rc) {
+ kfree(llap);
+ return rc;
+ }
+ seq = file->private_data;
+ seq->private = llap;
+
+ spin_lock(&sbi->ll_pglist_lock);
+ list_add(&llap->llap_proc_item, &sbi->ll_pglist);
+ spin_unlock(&sbi->ll_pglist_lock);
+
+ return 0;
+}
+
+static int llite_dump_pgcache_seq_release(struct inode *inode,
+ struct file *file)
+{
+ struct seq_file *seq = file->private_data;
+ struct ll_async_page *llap = seq->private;
+ struct ll_sb_info *sbi = llap->llap_cookie;
+
+ spin_lock(&sbi->ll_pglist_lock);
+ if (!list_empty(&llap->llap_proc_item))
+ list_del_init(&llap->llap_proc_item);
+ spin_unlock(&sbi->ll_pglist_lock);
+ kfree(llap);
+
+ return seq_release(inode, file);
+}
+
+struct file_operations llite_dump_pgcache_fops = {
+ .open = llite_dump_pgcache_seq_open,
+ .read = seq_read,
+ .release = llite_dump_pgcache_seq_release,
+};
+
#endif /* LPROCFS */
git://git.whamcloud.com / fs / lustre-release.git / commitdiff