feature: change Makefile and eio_cli for compling lifo but we use fif…

CLI/eio_cli

@@ -227,10 +227,10 @@ def sanity(hdd, ssd):
 	# Performs a very basic regression of operations			
 
 	modes = {3:"Write Through", 1:"Write Back", 2:"Read Only",0:"N/A"}
-	policies = {3:"rand", 1:"fifo", 2:"lru", 0:"N/A"}		
+	policies = {4:"lifo",3:"rand", 1:"fifo", 2:"lru", 0:"N/A"}		
 	blksizes = {"4096":4096, "2048":2048, "8192":8192,"":0}	
 	for mode in ["wb","wt","ro"]:
-		for policy in ["rand","fifo","lru"]:
+		for policy in ["lifo","rand","fifo","lru"]:
 			for blksize in ["4096","2048","8192"]:
 				cache = Cache_rec(name = "test_cache", src_name = hdd,\
 						ssd_name = ssd, policy = policy, mode = mode,\
@@ -265,7 +265,7 @@ class Cache_rec(Structure):
 		     blksize="", assoc=""): 
 
 		modes = {"wt":3,"wb":1,"ro":2,"":0}
-		policies = {"rand":3,"fifo":1, "lru":2,"":0}
+		policies = {"lifo":4,"rand":3,"fifo":1, "lru":2,"":0}
 		blksizes = {"4096":4096, "2048":2048, "8192":8192,"":0}	
 		associativity = {2048:128, 4096:256, 8192:512,0:0}
 
@@ -288,7 +288,7 @@ class Cache_rec(Structure):
 
 		# Display Cache info 
 		modes = {3:"Write Through", 1:"Write Back", 2:"Read Only",0:"N/A"}
-		policies = {3:"rand", 1:"fifo", 2:"lru", 0:"N/A"}
+		policies = {4:"lifo", 3:"rand", 1:"fifo", 2:"lru", 0:"N/A"}
 
 		print "Cache Name       : " + self.name 
 		print "Source Device    : " + self.src_name 
@@ -404,7 +404,7 @@ class Cache_rec(Structure):
 		cache_match_expr = make_udev_match_expr(self.ssd_name, self.name)
 		print cache_match_expr
 		modes = {3:"wt", 1:"wb", 2:"ro",0:"N/A"}
-		policies = {3:"rand", 1:"fifo", 2:"lru", 0:"N/A"}
+		policies = {4:"lifo", 3:"rand", 1:"fifo", 2:"lru", 0:"N/A"}
 
 		try: 	
 			udev_rule = udev_template.replace("<cache_name>",\
@@ -485,7 +485,7 @@ def create_parser():
 	parser_edit.add_argument("-m", action="store", dest="mode", \
 			choices=["wb","wt","ro"], help="cache mode",default="")
 	parser_edit.add_argument("-p", action="store", dest="policy", \
-				choices=["rand","fifo","lru"], help="cache \
+				choices=["lifo","rand","fifo","lru"], help="cache \
 				replacement policy",default="") 
 
 	#info
@@ -504,7 +504,7 @@ def create_parser():
 	parser_create.add_argument("-s", action="store", dest="ssd",\
 				required=True, help="name of the ssd device")
 	parser_create.add_argument("-p", action="store", dest="policy",\
-				   choices=["rand","fifo","lru"],\
+				   choices=["lifo","rand","fifo","lru"],\
 				   help="cache replacement policy",default="lru")
 	parser_create.add_argument("-m", action="store", dest="mode",\
 				   choices=["wb","wt","ro"],\
@@ -521,7 +521,7 @@ def create_parser():
 	parser_enable.add_argument("-s", action="store", dest="ssd",\
 				   required=True, help="name of the ssd device")
 	parser_enable.add_argument("-p", action="store", dest="policy",
-				   choices=["rand","fifo","lru"],\
+				   choices=["lifo","rand","fifo","lru"],\
 				   help="cache replacement policy",default="lru")
 	parser_enable.add_argument("-m", action="store", dest="mode",\
 				   choices=["wb","wt","ro"],\
@@ -563,6 +563,7 @@ def main():
 	run_cmd("/sbin/modprobe enhanceio_fifo")
 	run_cmd("/sbin/modprobe enhanceio_lru")
 	run_cmd("/sbin/modprobe enhanceio_rand")
+	run_cmd("/sbin/modprobe enhanceio_lifo")
 
 	f = open("/run/eio.lock", "w")
 	fcntl.flock(f, fcntl.LOCK_EX)

Driver/enhanceio/Kconfig

@@ -15,7 +15,7 @@ config ENHANCEIO
 	The caching engine is a loadable kernel module ("enhanceio.ko")
 	implemented as a device mapper target.	The cache replacement
 	policies are implemented as loadable kernel modules
-	("enhanceio_fifo.ko", "enhanceio_lru.ko") that register with
+	("enhanceio_fifo.ko", "enhanceio_lru.ko", "enhanceio_lifo.ko") that register with
 	the caching engine module.
 
 	If unsure, say N.

Driver/enhanceio/Makefile

@@ -7,7 +7,7 @@ KERNEL_SOURCE_VERSION ?= $(shell uname -r)
 KERNEL_TREE ?= /lib/modules/$(KERNEL_SOURCE_VERSION)/build
 EXTRA_CFLAGS += -I$(KERNEL_TREE)/drivers/md -I./ -DCOMMIT_REV="\"$(COMMIT_REV)\""
 EXTRA_CFLAGS += -I$(KERNEL_TREE)/include/ -I$(KERNEL_TREE)/include/linux 
-obj-m	+= enhanceio.o enhanceio_lru.o enhanceio_fifo.o  enhanceio_rand.o
+obj-m	+= enhanceio.o enhanceio_lru.o enhanceio_fifo.o  enhanceio_rand.o enhanceio_lifo.o
 enhanceio-y	+= \
 	eio_conf.o \
 	eio_ioctl.o \
@@ -20,6 +20,7 @@ enhanceio-y	+= \
 	eio_ttc.o
 enhanceio_fifo-y	+= eio_fifo.o
 enhanceio_rand-y	+= eio_rand.o
+enhanceio_lifo-y	+= eio_lifo.o
 enhanceio_lru-y	+= eio_lru.o
 .PHONY: all
 all: modules
@@ -33,6 +34,7 @@ modules_install: modules
 	install -o root -g root -m 0755 enhanceio_rand.ko $(DESTDIR)/lib/modules/$(KERNEL_SOURCE_VERSION)/extra/enhanceio/
 	install -o root -g root -m 0755 enhanceio_fifo.ko $(DESTDIR)/lib/modules/$(KERNEL_SOURCE_VERSION)/extra/enhanceio/
 	install -o root -g root -m 0755 enhanceio_lru.ko $(DESTDIR)/lib/modules/$(KERNEL_SOURCE_VERSION)/extra/enhanceio/
+	install -o root -g root -m 0755 enhanceio_lifo.ko $(DESTDIR)/lib/modules/$(KERNEL_SOURCE_VERSION)/extra/enhanceio/
 	depmod -a
 .PHONY: install
 install: modules_install

Driver/enhanceio/dkms.conf

@@ -13,3 +13,7 @@ DEST_MODULE_LOCATION[1]="/updates"
 
 BUILT_MODULE_NAME[2]="enhanceio_lru"
 DEST_MODULE_LOCATION[2]="/updates"
+
+
+BUILT_MODULE_NAME[3]="enhanceio_lifo"
+DEST_MODULE_LOCATION[3]="/updates"

Driver/enhanceio/eio.h

@@ -379,8 +379,9 @@ struct flash_cacheblock {
 #define CACHE_REPL_FIFO         1
 #define CACHE_REPL_LRU          2
 #define CACHE_REPL_RANDOM       3
+#define CACHE_REPL_LIFO	        4
 #define CACHE_REPL_FIRST        CACHE_REPL_FIFO
-#define CACHE_REPL_LAST         CACHE_REPL_RANDOM
+#define CACHE_REPL_LAST         CACHE_REPL_LIFO
 #define CACHE_REPL_DEFAULT      CACHE_REPL_FIFO
 
 struct eio_policy_and_name {
@@ -393,6 +394,7 @@ static const struct eio_policy_and_name eio_policy_names[] = {
 	{ CACHE_REPL_FIFO,   "fifo" },
 	{ CACHE_REPL_LRU,    "lru"  },
 	{ CACHE_REPL_RANDOM, "rand" },
+	{ CACHE_REPL_LIFO,   "lifo" },
 };
 
 

Driver/enhanceio/eio_fifo.c

@@ -236,4 +236,4 @@ module_exit(fifo_unregister);
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("FIFO policy for EnhanceIO");
-MODULE_AUTHOR("STEC, Inc. based on code by Facebook");
+MODULE_AUTHOR("STEC, Inc. based on code by Facebook");

Driver/enhanceio/eio_lifo.c

@@ -0,0 +1,237 @@
+/*
+ *  eio_lifo.c
+ *
+ *  Copyright (C) 2012 STEC, Inc. All rights not specifically granted
+ *   under a license included herein are reserved
+ *  Made EnhanceIO specific changes.
+ *   Saied Kazemi <skazemi@stec-inc.com>
+ *   Siddharth Choudhuri <schoudhuri@stec-inc.com>
+ *
+ *  Copyright 2010 Facebook, Inc.
+ *   Author: Mohan Srinivasan (mohan@facebook.com)
+ *
+ *  Based on DM-Cache:
+ *   Copyright (C) International Business Machines Corp., 2006
+ *   Author: Ming Zhao (mingzhao@ufl.edu)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; under version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "eio.h"
+/* Generic policy functions prototypes */
+int eio_lifo_init(struct cache_c *);
+void eio_lifo_exit(void);
+int eio_lifo_cache_sets_init(struct eio_policy *);
+int eio_lifo_cache_blk_init(struct eio_policy *);
+void eio_lifo_find_reclaim_dbn(struct eio_policy *, index_t, index_t *);
+int eio_lifo_clean_set(struct eio_policy *, index_t, int);
+
+/* Per policy instance initialization */
+struct eio_policy *eio_lifo_instance_init(void);
+
+/* Per cache set data structure */
+struct eio_lifo_cache_set {
+	index_t set_lifo_next;
+	index_t set_clean_next;
+};
+
+/*
+ * Context that captures the LIFO replacement policy
+ */
+static struct eio_policy_header eio_lifo_ops = {
+	.sph_name		= CACHE_REPL_LIFO,
+	.sph_instance_init	= eio_lifo_instance_init,
+};
+
+/*
+ * Initialize LIFO policy.
+ */
+int eio_lifo_init(struct cache_c *dmc)
+{
+	return 0;
+}
+
+/*
+ * Initialize LIFO data structure called from ctr.
+ */
+int eio_lifo_cache_sets_init(struct eio_policy *p_ops)
+{
+	int i;
+	sector_t order;
+	struct cache_c *dmc = p_ops->sp_dmc;
+	struct eio_lifo_cache_set *cache_sets;
+
+	pr_info("Initializing lifo cache sets\n");
+	order = (dmc->size >> dmc->consecutive_shift) * 
+		sizeof(struct eio_lifo_cache_set);
+
+	dmc->sp_cache_set = vmalloc((size_t)order);
+	if (dmc->sp_cache_set == NULL)
+		return -ENOMEM;
+
+	cache_sets = (struct eio_lifo_cache_set *)dmc->sp_cache_set;
+
+	for (i = 0; i < (int)(dmc->size >> dmc->consecutive_shift); i++) {
+		cache_sets[i].set_lifo_next = i * dmc->assoc;
+		cache_sets[i].set_clean_next = i * dmc->assoc;
+	}
+
+	return 0;
+}
+
+/*
+ * The actual function that returns a victim block in index.
+ */
+void eio_lifo_find_reclaim_dbn(struct eio_policy *p_ops, index_t start_index, 
+						 	  	index_t *index)
+{
+	index_t end_index;
+	int slots_searched = 0;
+	index_t i;
+	index_t set;
+	struct eio_lifo_cache_set *cache_sets;
+	struct cache_c *dmc = p_ops->sp_dmc;
+
+	set = start_index / dmc->assoc;
+	end_index = start_index + dmc->assoc;
+	cache_sets = (struct eio_lifo_cache_set *)dmc->sp_cache_set;
+
+	i = cache_sets[set].set_lifo_next;
+	while (slots_searched < (int)dmc->assoc) {
+		EIO_ASSERT(i >= start_index);
+		EIO_ASSERT(i < end_index);
+		if (EIO_CACHE_STATE_GET(dmc, i) == VALID) {
+			*index = i;
+			break;
+		}
+		slots_searched++;
+		i--;
+		if (i == start_index - 1)
+			i = end_index - 1;
+	}
+	i--;
+	if (i == start_index - 1)
+		i = end_index - 1;
+	cache_sets[set].set_lifo_next = i;
+}
+
+/*
+ * Go through the entire set and clean.
+ */
+int eio_lifo_clean_set(struct eio_policy *p_ops, index_t set, int to_clean)
+{
+	index_t i;
+	int scanned = 0, nr_writes = 0;
+	index_t start_index;
+	index_t end_index;
+	struct eio_lifo_cache_set *cache_sets;
+	struct cache_c *dmc;
+
+	dmc = p_ops->sp_dmc;
+	cache_sets = (struct eio_lifo_cache_set *)dmc->sp_cache_set;
+	start_index = set * dmc->assoc;
+	end_index = start_index + dmc->assoc;
+	i = cache_sets[set].set_clean_next;
+
+	while ((scanned < (int)dmc->assoc) && (nr_writes < to_clean)) {
+		if ((EIO_CACHE_STATE_GET(dmc, i) & (DIRTY | BLOCK_IO_INPROG)) == DIRTY) {
+			EIO_CACHE_STATE_ON(dmc, i, DISKWRITEINPROG);
+			nr_writes++;
+		}
+		scanned++;
+		i++;
+		if (i == end_index)
+			i = start_index;
+	}
+	cache_sets[set].set_clean_next = i;
+
+	return nr_writes;
+}
+
+/*
+ * LIFO is per set, so do nothing on a per block init.
+ */
+int eio_lifo_cache_blk_init(struct eio_policy *p_ops)
+{
+	return 0;
+}
+
+/*
+ * Allocate a new instance of eio_policy per dmc
+ */
+struct eio_policy *eio_lifo_instance_init(void)
+{
+	struct eio_policy *new_instance;
+
+	new_instance = vmalloc(sizeof(struct eio_policy));
+	if (new_instance == NULL) {
+		pr_err("ssdscache_lifo_instance_init: vmalloc failed");
+		return NULL;
+	}
+
+	/* Initialize the LIFO specific functions and variables */
+	new_instance->sp_name = CACHE_REPL_LIFO;
+	new_instance->sp_policy.lru = NULL;
+	new_instance->sp_repl_init = eio_lifo_init;
+	new_instance->sp_repl_exit = eio_lifo_exit;
+	new_instance->sp_repl_sets_init = eio_lifo_cache_sets_init;
+	new_instance->sp_repl_blk_init = eio_lifo_cache_blk_init;
+	new_instance->sp_find_reclaim_dbn = eio_lifo_find_reclaim_dbn;
+	new_instance->sp_clean_set = eio_lifo_clean_set;
+	new_instance->sp_dmc = NULL;
+
+	try_module_get(THIS_MODULE);
+
+	pr_info("eio_lifo_instance_init: created new instance of LIFO");
+
+	return new_instance;
+}
+
+/*
+ * Cleanup an instance of eio_policy (called from dtr).
+ */
+void eio_lifo_exit(void)
+{
+	module_put(THIS_MODULE);
+}
+
+static
+int __init lifo_register(void)
+{
+	int ret;
+
+	ret = eio_register_policy(&eio_lifo_ops);
+	if (ret != 0)
+		pr_info("eio_lifo already registered");
+
+	return ret;
+}
+
+static
+void __exit lifo_unregister(void)
+{
+	int ret;
+
+	ret = eio_unregister_policy(&eio_lifo_ops);
+	if (ret != 0)
+		pr_err("eio_lifo unregister failed");
+}
+
+module_init(lifo_register);
+module_exit(lifo_unregister);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LIFO policy for EnhanceIO");
+MODULE_AUTHOR("STEC, Inc. based on code by Facebook");

Install-EIO

@@ -102,6 +102,8 @@ _LoadMods ()
     ${SBPREFIX}modprobe enhanceio_rand &&
     ${SBPREFIX}modprobe enhanceio_fifo &&
     ${SBPREFIX}modprobe enhanceio_lru &&
+    ${SBPREFIX}modprobe enhanceio_lifo &&
+
     return 0
     return 1
 }

Install.txt

@@ -113,6 +113,7 @@ Loading Modules:
    # modprode enhanceio_rand
    # modprode enhanceio_fifo
    # modprode enhanceio_lru
+   # modprode enhanceio_lifo
 
    Once the modules have been loaded you will be able to use eio_cli to create/modify caches.