Multi-file support

Makefile

@@ -1,5 +1,14 @@
 CC = gcc
 CFLAGS = -Wall -D_GNU_SOURCE -Wunused
+
+ifeq ($(filter-out %64 %64be %64eb %64le %64el s390x, $(shell uname -m)),)
+	LIBDIR ?= /usr/lib64
+else
+	LIBDIR ?= /usr/lib
+endif
+
+LDFLAGS = -L$(LIBDIR)
+
 LDLIBS = -pthread -lbpf -lm
 
 

README.md

@@ -4,17 +4,18 @@ query operations.  SimpleKV supports low-latency IO via the XRP BPF interface
 and can also run using user-space IO (`pread()`) on mainline (and XRP
 compatible) kernels.
 
-For usage instructions run `./simplekv --help` after compiling.
+For usage instructions run `LD_PRELOAD="/usr/lib64/libbpf.so.0" ./simplekv --help` after compiling.
 
 
 # Building
-SimpleKV is built using the provided Makefile. Compiling the simplekv binary
+SimpleKV is built using the provided Makefile. Compiling the `simplekv` binary
 is as simple as running `make`. To perform IO with XRP via the `--use-xrp`
 flag the corresponding BPF programs in the `xrp-bpf` directory must be
 compiled.
 
 These BPF programs require [libbpf](https://github.com/libbpf/libbpf) and an XRP compatible kernel.
 Before compiling, install libbpf via your distribution's package manager or source.
+Compiling these programs also requires installing `clang` and `llvm`.
 
 To compile on an XRP compatible kernel with libbpf, run:
 ```
@@ -26,6 +27,9 @@ Alternatively, you can compile simplekv without the BPF programs and use userspa
 make simplekv
 ```
 
+For the below commands, we assume your libbpf installation is located in the
+default directory specified by libbpf: `/usr/lib64` (for 64-bit architectures).
+
 # Running
 
 ## Create a Database File
@@ -45,39 +49,28 @@ space.
 
 To create a 6-layer database file:
 ```
-./simplekv 6-layer-db 6 create
+LD_PRELOAD="/usr/lib64/libbpf.so.0" ./simplekv 6-layer-db 6 create
 ```
 
 ## Running the benchmark
 SimpleKV supports get queries and range queries, both of which can be run with various options.
 Usage and option docs can be reviewed by passing the `--help` flag to either command:
 ```
-./simplekv 6-layer-db 6 get --help
-./simplekv 6-layer-db 6 range --help
+LD_PRELOAD="/usr/lib64/libbpf.so.0" ./simplekv 6-layer-db 6 get --help
+LD_PRELOAD="/usr/lib64/libbpf.so.0" ./simplekv 6-layer-db 6 range --help
 ```
 
 ### Using XRP
-Before running with XRP you must load the corresponding BPF function using the
-`xrp_loader` program built via the default make target. Note that GET and RANGE operations
-use separate BPF programs, so be sure to load the correct one.
-
-For GET operations:
-```
-LD_PRELOAD="/usr/lib64/libbpf.so.0" ./xrp_loader xrp-bpf/get_op.o
-```
-
-For RANGE operations:
-```
-LD_PRELOAD="/usr/lib64/libbpf.so.0" ./xrp_loader xrp-bpf/range_op.o
-```
 
 NOTE: You may need to change `LD_PRELOAD` depending on where `libbpf.so.0` is located on your machine.
 
 With the BPF program loaded, you can run a basic GET benchmark as follows:
 ```
-./simplekv 6-layer-db 6 get --requests=100000 --use-xrp
+sudo LD_PRELOAD="/usr/lib64/libbpf.so.0" ./simplekv 6-layer-db 6 get --requests=100000 --use-xrp
 ```
 
+Root access is required in order to load the bpf programs.
+
 ### CPU Configuration
 For consistent benchmark results you may need to disable CPU frequency scaling.
 

xrp-bpf/get.c

@@ -54,6 +54,7 @@ static __inline void set_context_next_index(struct bpf_xrp *context, struct Scat
         context->next_addr[0] = query->root_pointer;
         context->size[0] = BLK_SIZE;
     }
+    context->fd_arr[0] = context->cur_fd;
 }
 
 /* Mask to prevent out of bounds memory access */
@@ -65,6 +66,8 @@ unsigned int oliver_agg_func(struct bpf_xrp *context) {
     Node *node = (Node *) context->data;
     int *curr_idx = &query->current_index;
 
+    dbg_print("fd: %d\n", context->cur_fd );
+
     /* Three cases:
      *
      * 1. We've found the log offset in the previous iteration and are
@@ -112,12 +115,14 @@ unsigned int oliver_agg_func(struct bpf_xrp *context) {
         ptr__t base = query->value_ptr & ~(BLK_SIZE - 1);
         context->next_addr[0] = base;
         context->size[0] = BLK_SIZE;
+        context->fd_arr[0] = context->cur_fd;
         return 0;
     }
 
     /* Case 3: at an internal node, keep going */
     dbg_print("simplekv-bpf: case 3 - internal node\n");
     context->next_addr[0] = decode(nxt_node(query->keys[*curr_idx & EBPF_CONTEXT_MASK], node));
     context->size[0] = BLK_SIZE;
+    context->fd_arr[0] = context->cur_fd;
     return 0;
 }

xrp-bpf/range.c

@@ -49,6 +49,7 @@ static __inline unsigned int process_leaf(struct bpf_xrp *context, struct RangeQ
             if (curr_key >= first_key) {
                 /* Set up the next resubmit to read the value */
                 context->next_addr[0] = value_base(decode(node->ptr[*i & KEY_MASK]));
+                context->fd_arr[0] = context->cur_fd;
                 context->size[0] = BLK_SIZE;
 
                 key__t key = node->key[*i & KEY_MASK];
@@ -102,6 +103,7 @@ static __inline unsigned int process_leaf(struct bpf_xrp *context, struct RangeQ
         query->_state = RNG_READ_NODE;
         query->_node_key_ix = 0;
         context->next_addr[0] = node->next;
+        context->fd_arr[0] = context->cur_fd;
         context->size[0] = BLK_SIZE;
         return 0;
     }
@@ -138,6 +140,7 @@ static __inline unsigned int traverse_index(struct bpf_xrp *context, struct Rang
 
     /* Grab the next node in the traversal */
     context->next_addr[0] = decode(nxt_node(query->range_begin, node));
+    context->fd_arr[0] = context->cur_fd;
     context->size[0] = BLK_SIZE;
     return 0;
 }

xrp-bpf/simplekvspec.h

@@ -37,7 +37,6 @@ static __inline void print_query(struct Query *q) {
 static __inline void print_node(Node *node) {
     dbg_print("struct Node {\n");
 
-    dbg_print("\tnum = %ld\n", node->num);
     dbg_print("\ttype = %ld\n", node->type);
     dbg_print("\tkey[0] = %ld\n", node->key[0]);
     dbg_print("\tkey[30] = %ld\n", node->key[NODE_CAPACITY - 1]);
@@ -50,6 +49,4 @@ static __inline void print_node(Node *node) {
 #define dbg_print(...)
 #endif
 
-
-
 #endif