*/
#define DEBUG_SUBSYSTEM S_LLITE
+#include <linux/version.h>
#include <linux/lustre_lite.h>
#include <linux/lprocfs_status.h>
+#include <linux/seq_file.h>
+#include <linux/obd_support.h>
+#include "llite_internal.h"
-int rd_path(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+/* /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,
+ struct super_block *sb, char *osc, char *mdc)
{
return 0;
}
-int rd_fstype(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+void lprocfs_unregister_mountpoint(struct ll_sb_info *sbi){}
+#else
+
+long long mnt_instance;
+
+static int ll_rd_blksize(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
- struct super_block *sb = (struct super_block*)data;
-
- len += snprintf(page, count, "%s\n", sb->s_type->name);
- return len;
+ struct super_block *sb = (struct super_block *)data;
+ struct obd_statfs osfs;
+ int rc;
+
+ LASSERT(sb != NULL);
+ rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
+ if (!rc) {
+ *eof = 1;
+ rc = snprintf(page, count, "%u\n", osfs.os_bsize);
+ }
+
+ return rc;
}
-int rd_blksize(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+
+static int ll_rd_kbytestotal(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
- struct super_block *sb = (struct super_block*)data;
- struct statfs mystats;
+ struct super_block *sb = (struct super_block *)data;
+ struct obd_statfs osfs;
+ int rc;
+
+ LASSERT(sb != NULL);
+ rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
+ if (!rc) {
+ __u32 blk_size = osfs.os_bsize >> 10;
+ __u64 result = osfs.os_blocks;
+
+ while (blk_size >>= 1)
+ result <<= 1;
- (sb->s_op->statfs)(sb, &mystats);
- len += snprintf(page, count, LPU64"\n", (__u64)(mystats.f_bsize));
- return len;
+ *eof = 1;
+ rc = snprintf(page, count, LPU64"\n", result);
+ }
+ return rc;
}
-int rd_kbytestotal(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+
+static int ll_rd_kbytesfree(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
- struct super_block *sb = (struct super_block*)data;
- struct statfs mystats;
- __u32 blk_size;
- __u64 result;
+ struct super_block *sb = (struct super_block *)data;
+ struct obd_statfs osfs;
+ int rc;
- (sb->s_op->statfs)(sb, &mystats);
- blk_size = mystats.f_bsize;
- blk_size >>= 10;
- result = mystats.f_blocks;
-
- while(blk_size >>= 1){
- result <<= 1;
+ LASSERT(sb != NULL);
+ rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
+ if (!rc) {
+ __u32 blk_size = osfs.os_bsize >> 10;
+ __u64 result = osfs.os_bfree;
+
+ while (blk_size >>= 1)
+ result <<= 1;
+
+ *eof = 1;
+ rc = snprintf(page, count, LPU64"\n", result);
}
-
- len += snprintf(page, count, LPU64"\n", result);
- return len;
-
+ return rc;
}
-
-int rd_kbytesfree(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+static int ll_rd_kbytesavail(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
- struct super_block *sb = (struct super_block*)data;
- struct statfs mystats;
- __u32 blk_size;
- __u64 result;
+ struct super_block *sb = (struct super_block *)data;
+ struct obd_statfs osfs;
+ int rc;
- (sb->s_op->statfs)(sb, &mystats);
- blk_size = mystats.f_bsize;
- blk_size >>= 10;
- result = mystats.f_bfree;
-
- while(blk_size >>= 1){
- result <<= 1;
- }
-
- len += snprintf(page, count, LPU64"\n", result);
- return len;
+ LASSERT(sb != NULL);
+ rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
+ if (!rc) {
+ __u32 blk_size = osfs.os_bsize >> 10;
+ __u64 result = osfs.os_bavail;
+
+ while (blk_size >>= 1)
+ result <<= 1;
-
+ *eof = 1;
+ rc = snprintf(page, count, LPU64"\n", result);
+ }
+ return rc;
}
-int rd_filestotal(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+static int ll_rd_filestotal(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
-
- int len = 0;
- struct super_block *sb = (struct super_block*)data;
- struct statfs mystats;
-
- (sb->s_op->statfs)(sb, &mystats);
- len += snprintf(page, count, LPU64"\n", (__u64)(mystats.f_files));
- return len;
+ struct super_block *sb = (struct super_block *)data;
+ struct obd_statfs osfs;
+ int rc;
+
+ LASSERT(sb != NULL);
+ rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
+ if (!rc) {
+ *eof = 1;
+ rc = snprintf(page, count, LPU64"\n", osfs.os_files);
+ }
+ return rc;
}
-int rd_filesfree(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+static int ll_rd_filesfree(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
-
- int len = 0;
- struct super_block *sb = (struct super_block*)data;
- struct statfs mystats;
-
- (sb->s_op->statfs)(sb, &mystats);
- len += snprintf(page, count, LPU64"\n", (__u64)(mystats.f_ffree));
- return len;
+ struct super_block *sb = (struct super_block *)data;
+ struct obd_statfs osfs;
+ int rc;
+
+ LASSERT(sb != NULL);
+ rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
+ if (!rc) {
+ *eof = 1;
+ rc = snprintf(page, count, LPU64"\n", osfs.os_ffree);
+ }
+ return rc;
+
}
-int rd_filegroups(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+#if 0
+static int ll_rd_path(char *page, char **start, off_t off, int count, int *eof,
+ void *data)
{
return 0;
}
-int rd_uuid(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+#endif
+
+static int ll_rd_fstype(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
struct super_block *sb = (struct super_block*)data;
- struct ll_sb_info *sbi = ll_s2sbi(sb);
- len += snprintf(page, count, "%s\n", sbi->ll_sb_uuid);
- return len;
+ LASSERT(sb != NULL);
+ *eof = 1;
+ return snprintf(page, count, "%s\n", sb->s_type->name);
}
-int rd_dev_name(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+
+static int ll_rd_sb_uuid(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
- struct obd_device* dev = (struct obd_device*)data;
- len += snprintf(page, count, "%s\n", dev->obd_name);
- return len;
+ struct super_block *sb = (struct super_block *)data;
+
+ LASSERT(sb != NULL);
+ *eof = 1;
+ return snprintf(page, count, "%s\n", ll_s2sbi(sb)->ll_sb_uuid.uuid);
}
-int rd_dev_uuid(char* page, char **start, off_t off, int count, int *eof,
- void *data)
+static int ll_rd_read_ahead(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
{
- int len = 0;
- struct obd_device* dev = (struct obd_device*)data;
- len += snprintf(page, count, "%s\n", dev->obd_uuid);
- return len;
+ struct super_block *sb = (struct super_block*)data;
+ struct ll_sb_info *sbi = ll_s2sbi(sb);
+ int val, rc;
+ ENTRY;
+
+ *eof = 1;
+ val = (sbi->ll_flags & LL_SBI_READAHEAD) ? 1 : 0;
+ rc = snprintf(page, count, "%d\n", val);
+ RETURN(rc);
}
+static int ll_wr_read_ahead(struct file *file, const char *buffer,
+ unsigned long count, void *data)
+{
+ struct super_block *sb = (struct super_block*)data;
+ struct ll_sb_info *sbi = ll_s2sbi(sb);
+ int readahead;
+ ENTRY;
+
+ if (1 != sscanf(buffer, "%d", &readahead))
+ RETURN(-EINVAL);
+
+ if (readahead)
+ sbi->ll_flags |= LL_SBI_READAHEAD;
+ else
+ sbi->ll_flags &= ~LL_SBI_READAHEAD;
+
+ RETURN(count);
+}
-struct lprocfs_vars status_var_nm_1[] = {
- {"status/uuid", rd_uuid, 0, 0},
- {"status/mntpt_path", rd_path, 0, 0},
- {"status/fstype", rd_fstype, 0, 0},
- {"status/blocksize",rd_blksize, 0, 0},
- {"status/kbytestotal",rd_kbytestotal, 0, 0},
- {"status/kbytesfree", rd_kbytesfree, 0, 0},
- {"status/filestotal", rd_filestotal, 0, 0},
- {"status/filesfree", rd_filesfree, 0, 0},
- {"status/filegroups", rd_filegroups, 0, 0},
- {0}
+static struct lprocfs_vars lprocfs_obd_vars[] = {
+ { "uuid", ll_rd_sb_uuid, 0, 0 },
+ //{ "mntpt_path", ll_rd_path, 0, 0 },
+ { "fstype", ll_rd_fstype, 0, 0 },
+ { "blocksize", ll_rd_blksize, 0, 0 },
+ { "kbytestotal", ll_rd_kbytestotal, 0, 0 },
+ { "kbytesfree", ll_rd_kbytesfree, 0, 0 },
+ { "kbytesavail", ll_rd_kbytesavail, 0, 0 },
+ { "filestotal", ll_rd_filestotal, 0, 0 },
+ { "filesfree", ll_rd_filesfree, 0, 0 },
+ //{ "filegroups", lprocfs_rd_filegroups, 0, 0 },
+ { "read_ahead", ll_rd_read_ahead, ll_wr_read_ahead, 0 },
+ { 0 }
};
-/*
- * Proc registration function for Lustre
- * file system
- */
+#define MAX_STRING_SIZE 128
+
+struct llite_file_opcode {
+ __u32 opcode;
+ __u32 type;
+ const char *opname;
+} llite_opcode_table[LPROC_LL_FILE_OPCODES] = {
+ /* file operation */
+ { LPROC_LL_DIRTY_HITS, LPROCFS_TYPE_REGS, "dirty_pages_hits" },
+ { LPROC_LL_DIRTY_MISSES, LPROCFS_TYPE_REGS, "dirty_pages_misses" },
+ { LPROC_LL_WB_WRITEPAGE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "writeback_from_writepage" },
+ { LPROC_LL_WB_PRESSURE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "writeback_from_pressure" },
+ { LPROC_LL_WB_OK, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "writeback_ok_pages" },
+ { LPROC_LL_WB_FAIL, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "writeback_failed_pages" },
+ { LPROC_LL_READ_BYTES, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_BYTES,
+ "read_bytes" },
+ { LPROC_LL_WRITE_BYTES, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_BYTES,
+ "write_bytes" },
+ { LPROC_LL_BRW_READ, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "brw_read" },
+ { LPROC_LL_BRW_WRITE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "brw_write" },
+
+ { LPROC_LL_IOCTL, LPROCFS_TYPE_REGS, "ioctl" },
+ { LPROC_LL_OPEN, LPROCFS_TYPE_REGS, "open" },
+ { LPROC_LL_RELEASE, LPROCFS_TYPE_REGS, "close" },
+ { LPROC_LL_MAP, LPROCFS_TYPE_REGS, "mmap" },
+ { LPROC_LL_LLSEEK, LPROCFS_TYPE_REGS, "seek" },
+ { LPROC_LL_FSYNC, LPROCFS_TYPE_REGS, "fsync" },
+ /* inode operation */
+ { LPROC_LL_SETATTR, LPROCFS_TYPE_REGS, "setattr" },
+ { LPROC_LL_TRUNC, LPROCFS_TYPE_REGS, "punch" },
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
+ { LPROC_LL_GETATTR, LPROCFS_TYPE_REGS, "getattr" },
+#else
+ { LPROC_LL_REVALIDATE, LPROCFS_TYPE_REGS, "getattr" },
+#endif
+ /* special inode operation */
+ { LPROC_LL_STAFS, LPROCFS_TYPE_REGS, "statfs" },
+ { LPROC_LL_ALLOC_INODE, LPROCFS_TYPE_REGS, "alloc_inode" },
+ { LPROC_LL_DIRECT_READ, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "direct_read" },
+ { LPROC_LL_DIRECT_WRITE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
+ "direct_write" },
+};
-#define MAX_STRING_SIZE 100
-void ll_proc_namespace(struct super_block* sb, char* osc, char* mdc)
+int lprocfs_register_mountpoint(struct proc_dir_entry *parent,
+ struct super_block *sb, char *osc, char *mdc)
{
- char mnt_name[MAX_STRING_SIZE];
- char uuid_name[MAX_STRING_SIZE];
- struct lprocfs_vars d_vars[3];
+ struct lprocfs_vars lvars[2];
struct ll_sb_info *sbi = ll_s2sbi(sb);
- struct obd_device* obd;
- int err;
-
-
- /* Register this mount instance with LProcFS */
- snprintf(mnt_name, 100, "mount_%s", sbi->ll_sb_uuid);
- sbi->ll_proc_root = lprocfs_reg_mnt(mnt_name);
- if (!sbi->ll_proc_root)
- CDEBUG(D_OTHER, "Could not register FS");
- /* Add the static configuration info */
- err = lprocfs_add_vars(sbi->ll_proc_root,status_var_nm_1, sb);
+ struct obd_device *obd;
+ 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));
+
+ name[MAX_STRING_SIZE] = '\0';
+ lvars[0].name = name;
+
+ LASSERT(sbi != NULL);
+ LASSERT(mdc != NULL);
+ LASSERT(osc != NULL);
+
+ /* Mount info */
+ snprintf(name, MAX_STRING_SIZE, "fs%llu", mnt_instance);
+
+ mnt_instance++;
+ sbi->ll_proc_root = lprocfs_register(name, parent, NULL, NULL);
+ if (IS_ERR(sbi->ll_proc_root)) {
+ err = PTR_ERR(sbi->ll_proc_root);
+ sbi->ll_proc_root = NULL;
+ RETURN(err);
+ }
+
+ entry = create_proc_entry("dump_page_cache", 0444, sbi->ll_proc_root);
+ if (entry == NULL)
+ GOTO(out, err = -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;
+ goto out;
+ }
+ /* do counter init */
+ for (id = 0; id < LPROC_LL_FILE_OPCODES; id++) {
+ __u32 type = llite_opcode_table[id].type;
+ void *ptr = NULL;
+ if (type & LPROCFS_TYPE_REGS)
+ ptr = "regs";
+ else {
+ if (type & LPROCFS_TYPE_BYTES)
+ ptr = "bytes";
+ else {
+ if (type & LPROCFS_TYPE_PAGES)
+ ptr = "pages";
+ }
+ }
+ lprocfs_counter_init(svc_stats, llite_opcode_table[id].opcode,
+ (type & LPROCFS_CNTR_AVGMINMAX),
+ llite_opcode_table[id].opname, ptr);
+ }
+ err = lprocfs_register_stats(sbi->ll_proc_root, "stats", svc_stats);
if (err)
- CDEBUG(D_OTHER, "Unable to add procfs variables\n");
+ goto out;
+ else
+ sbi->ll_stats = svc_stats;
+ /* need place to keep svc_stats */
- /* MDC */
- obd = class_uuid2obd(mdc);
+ /* Static configuration info */
+ err = lprocfs_add_vars(sbi->ll_proc_root, lprocfs_obd_vars, sb);
+ if (err)
+ goto out;
-
- snprintf(mnt_name, MAX_STRING_SIZE, "status/%s/common_name",
- obd->obd_type->typ_name);
+ /* MDC info */
+ obd = class_name2obd(mdc);
- memset(d_vars, 0, sizeof(d_vars));
- d_vars[0].read_fptr = rd_dev_name;
- d_vars[0].write_fptr = NULL;
- d_vars[0].name = mnt_name;
+ LASSERT(obd != NULL);
+ LASSERT(obd->obd_type != NULL);
+ LASSERT(obd->obd_type->typ_name != NULL);
- snprintf(uuid_name, MAX_STRING_SIZE, "status/%s/uuid",
+ snprintf(name, MAX_STRING_SIZE, "%s/common_name",
obd->obd_type->typ_name);
- d_vars[1].read_fptr = rd_dev_uuid;
- d_vars[1].write_fptr = NULL;
- d_vars[1].name = uuid_name;
-
- err = lprocfs_add_vars(sbi->ll_proc_root, d_vars, obd);
+ lvars[0].read_fptr = lprocfs_rd_name;
+ err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
if (err)
- CDEBUG(D_OTHER, "Unable to add fs proc dynamic variables\n");
+ goto out;
- /* OSC or LOV*/
- obd = class_uuid2obd(osc);
+ snprintf(name, MAX_STRING_SIZE, "%s/uuid", obd->obd_type->typ_name);
+ lvars[0].read_fptr = lprocfs_rd_uuid;
+ err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
+ if (err)
+ goto out;
- /* Reuse mnt_name */
- snprintf(mnt_name, MAX_STRING_SIZE, "status/%s/common_name",
- obd->obd_type->typ_name);
+ /* OSC */
+ obd = class_name2obd(osc);
- memset(d_vars, 0, sizeof(d_vars));
- d_vars[0].read_fptr = rd_dev_name;
- d_vars[0].write_fptr = NULL;
- d_vars[0].name = mnt_name;
+ LASSERT(obd != NULL);
+ LASSERT(obd->obd_type != NULL);
+ LASSERT(obd->obd_type->typ_name != NULL);
- snprintf(uuid_name, MAX_STRING_SIZE, "status/%s/uuid",
+ snprintf(name, MAX_STRING_SIZE, "%s/common_name",
obd->obd_type->typ_name);
- d_vars[1].read_fptr = rd_dev_uuid;
- d_vars[1].write_fptr = NULL;
- d_vars[1].name = uuid_name;
-
- err = lprocfs_add_vars(sbi->ll_proc_root, d_vars, obd);
+ lvars[0].read_fptr = lprocfs_rd_name;
+ err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
if (err)
- CDEBUG(D_OTHER, "Unable to add fs proc dynamic variables\n");
+ goto out;
+
+ snprintf(name, MAX_STRING_SIZE, "%s/uuid", obd->obd_type->typ_name);
+ lvars[0].read_fptr = lprocfs_rd_uuid;
+ err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
+out:
+ if (err) {
+ if (svc_stats)
+ lprocfs_free_stats(svc_stats);
+ if (sbi->ll_proc_root)
+ lprocfs_remove(sbi->ll_proc_root);
+ }
+ RETURN(err);
+}
+void lprocfs_unregister_mountpoint(struct ll_sb_info *sbi)
+{
+ if (sbi->ll_proc_root) {
+ struct proc_dir_entry *file_stats =
+ lprocfs_srch(sbi->ll_proc_root, "stats");
+
+ if (file_stats) {
+ lprocfs_free_stats(sbi->ll_stats);
+ lprocfs_remove(file_stats);
+ }
+ }
}
#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 = PDE(inode);
+ struct ll_async_page *llap;
+ struct seq_file *seq;
+ struct ll_sb_info *sbi = dp->data;
+ int rc;
+
+ OBD_ALLOC_GFP(llap, 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) {
+ OBD_FREE(llap, sizeof(*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);
+ OBD_FREE(llap, sizeof(*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 */