From: Zhi Yong Wu <[email protected]> FS_IOC_GET_HEAT_INFO: return a struct containing the various metrics collected in hot_freq_data structs, and also return a calculated data temperature based on those metrics.
Optionally, retrieve the temperature from the hot data hash list instead of recalculating it. Signed-off-by: Chandra Seetharaman <[email protected]> Signed-off-by: Zhi Yong Wu <[email protected]> --- fs/compat_ioctl.c | 5 +++ fs/ioctl.c | 71 +++++++++++++++++++++++++++++++++++++++ include/linux/hot_tracking.h | 10 +++++- include/uapi/linux/hot_tracking.h | 33 ++++++++++++++++++ 4 files changed, 118 insertions(+), 1 deletion(-) create mode 100644 include/uapi/linux/hot_tracking.h diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c index 5d19acf..9026b8a 100644 --- a/fs/compat_ioctl.c +++ b/fs/compat_ioctl.c @@ -57,6 +57,7 @@ #include <linux/i2c-dev.h> #include <linux/atalk.h> #include <linux/gfp.h> +#include <linux/hot_tracking.h> #include <net/bluetooth/bluetooth.h> #include <net/bluetooth/hci.h> @@ -1399,6 +1400,9 @@ COMPATIBLE_IOCTL(TIOCSTART) COMPATIBLE_IOCTL(TIOCSTOP) #endif +/*Hot data tracking*/ +COMPATIBLE_IOCTL(FS_IOC_GET_HEAT_INFO) + /* fat 'r' ioctls. These are handled by fat with ->compat_ioctl, but we don't want warnings on other file systems. So declare them as compatible here. */ @@ -1578,6 +1582,7 @@ asmlinkage long compat_sys_ioctl(unsigned int fd, unsigned int cmd, case FIBMAP: case FIGETBSZ: case FIONREAD: + case FS_IOC_GET_HEAT_INFO: if (S_ISREG(file_inode(f.file)->i_mode)) break; /*FALL THROUGH*/ diff --git a/fs/ioctl.c b/fs/ioctl.c index fd507fb..b3693ea 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -15,6 +15,7 @@ #include <linux/writeback.h> #include <linux/buffer_head.h> #include <linux/falloc.h> +#include "hot_tracking.h" #include <asm/ioctls.h> @@ -537,6 +538,73 @@ static int ioctl_fsthaw(struct file *filp) } /* + * Retrieve information about access frequency for the given inode. + * + * The temperature that is returned can be "live" -- that is, recalculated when + * the ioctl is called -- or it can be returned from the map list, reflecting + * the (possibly old) value that the system will use when considering files + * for migration. This behavior is determined by hot_heat_info->live. + */ +static int ioctl_heat_info(struct file *file, void __user *argp) +{ + struct inode *inode = file_inode(file); + struct hot_info *root = inode->i_sb->s_hot_root; + struct hot_heat_info heat_info; + struct hot_inode_item *he; + int ret = 0; + + /* The 'live' field need to be read from the user space */ + if (copy_from_user((void *)&heat_info, + argp, + sizeof(struct hot_heat_info)) != 0) { + ret = -EFAULT; + goto err; + } + + he = hot_inode_item_lookup(root, inode->i_ino); + if (IS_ERR(he)) { + /* we don't have any info on this file yet */ + ret = -ENODATA; + goto err; + } + + heat_info.avg_delta_reads = + (__u64) he->freq.avg_delta_reads; + heat_info.avg_delta_writes = + (__u64) he->freq.avg_delta_writes; + heat_info.last_read_time = + (__u64) timespec_to_ns(&he->freq.last_read_time); + heat_info.last_write_time = + (__u64) timespec_to_ns(&he->freq.last_write_time); + heat_info.num_reads = (__u32) he->freq.nr_reads; + heat_info.num_writes = (__u32) he->freq.nr_writes; + + if (heat_info.live > 0) { + /* + * got a request for live temperature, + * call hot_calc_temp() to recalculate + */ + heat_info.temp = hot_temp_calc(&he->freq); + } else { + /* not live temperature, get it from the map list */ + heat_info.temp = he->freq.last_temp; + } + + spin_lock(&root->t_lock); + hot_inode_item_put(he); + spin_unlock(&root->t_lock); + + if (copy_to_user(argp, (void *)&heat_info, + sizeof(struct hot_heat_info))) { + ret = -EFAULT; + goto err; + } + +err: + return ret; +} + +/* * When you add any new common ioctls to the switches above and below * please update compat_sys_ioctl() too. * @@ -591,6 +659,9 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, case FIGETBSZ: return put_user(inode->i_sb->s_blocksize, argp); + case FS_IOC_GET_HEAT_INFO: + return ioctl_heat_info(filp, argp); + default: if (S_ISREG(inode->i_mode)) error = file_ioctl(filp, cmd, arg); diff --git a/include/linux/hot_tracking.h b/include/linux/hot_tracking.h index 67468a51..0ee9ca2 100644 --- a/include/linux/hot_tracking.h +++ b/include/linux/hot_tracking.h @@ -15,11 +15,11 @@ #ifndef _LINUX_HOTTRACK_H #define _LINUX_HOTTRACK_H -#include <linux/types.h> #include <linux/slab.h> #include <linux/rbtree.h> #include <linux/kref.h> #include <linux/fs.h> +#include <uapi/linux/hot_tracking.h> #define MAP_BITS 8 #define MAP_SIZE (1 << MAP_BITS) @@ -85,6 +85,14 @@ struct hot_info { struct shrinker hot_shrink; }; +/* + * Hot data tracking ioctls: + * + * HOT_INFO - retrieve info on frequency of access + */ +#define FS_IOC_GET_HEAT_INFO _IOR('f', 17, \ + struct hot_heat_info) + extern int hot_track_init(struct super_block *sb); extern void hot_track_exit(struct super_block *sb); extern void hot_freqs_update(struct inode *inode, loff_t start, diff --git a/include/uapi/linux/hot_tracking.h b/include/uapi/linux/hot_tracking.h new file mode 100644 index 0000000..09dfc00 --- /dev/null +++ b/include/uapi/linux/hot_tracking.h @@ -0,0 +1,33 @@ +/* + * include/uapi/linux/hot_tracking.h + * + * This file has definitions for VFS hot tracking + * structures etc. + * + * Copyright (C) 2013 IBM Corp. All rights reserved. + * Written by Zhi Yong Wu <[email protected]> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + */ + +#ifndef _UAPI_HOTTRACK_H +#define _UAPI_HOTTRACK_H + +#include <linux/types.h> + +struct hot_heat_info { + __u8 live; + __u8 resv[3]; + __u32 temp; + __u64 avg_delta_reads; + __u64 avg_delta_writes; + __u64 last_read_time; + __u64 last_write_time; + __u32 num_reads; + __u32 num_writes; + __u64 future[4]; /* For future expansions */ +}; + +#endif /* _UAPI_HOTTRACK_H */ -- 1.7.11.7 -- 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/
