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-rw-r--r--arch/x86/net/bpf_jit_comp.c150
-rw-r--r--include/linux/bpf.h72
-rw-r--r--include/linux/filter.h40
-rw-r--r--kernel/bpf/Makefile1
-rw-r--r--kernel/bpf/dispatcher.c158
-rw-r--r--kernel/bpf/syscall.c26
-rw-r--r--kernel/bpf/trampoline.c24
-rw-r--r--net/bpf/test_run.c15
-rw-r--r--net/core/dev.c19
-rw-r--r--net/core/filter.c8
-rw-r--r--tools/testing/selftests/bpf/prog_tests/xdp_perf.c25
11 files changed, 501 insertions, 37 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index b8be18427277..4c8a2d1f8470 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -10,10 +10,12 @@
#include <linux/if_vlan.h>
#include <linux/bpf.h>
#include <linux/memory.h>
+#include <linux/sort.h>
#include <asm/extable.h>
#include <asm/set_memory.h>
#include <asm/nospec-branch.h>
#include <asm/text-patching.h>
+#include <asm/asm-prototypes.h>
static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
{
@@ -1530,6 +1532,154 @@ int arch_prepare_bpf_trampoline(void *image, struct btf_func_model *m, u32 flags
return 0;
}
+static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ s64 offset;
+
+ offset = func - (ip + 2 + 4);
+ if (!is_simm32(offset)) {
+ pr_err("Target %p is out of range\n", func);
+ return -EINVAL;
+ }
+ EMIT2_off32(0x0F, jmp_cond + 0x10, offset);
+ *pprog = prog;
+ return 0;
+}
+
+static void emit_nops(u8 **pprog, unsigned int len)
+{
+ unsigned int i, noplen;
+ u8 *prog = *pprog;
+ int cnt = 0;
+
+ while (len > 0) {
+ noplen = len;
+
+ if (noplen > ASM_NOP_MAX)
+ noplen = ASM_NOP_MAX;
+
+ for (i = 0; i < noplen; i++)
+ EMIT1(ideal_nops[noplen][i]);
+ len -= noplen;
+ }
+
+ *pprog = prog;
+}
+
+static int emit_fallback_jump(u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int err = 0;
+
+#ifdef CONFIG_RETPOLINE
+ /* Note that this assumes the the compiler uses external
+ * thunks for indirect calls. Both clang and GCC use the same
+ * naming convention for external thunks.
+ */
+ err = emit_jump(&prog, __x86_indirect_thunk_rdx, prog);
+#else
+ int cnt = 0;
+
+ EMIT2(0xFF, 0xE2); /* jmp rdx */
+#endif
+ *pprog = prog;
+ return err;
+}
+
+static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs)
+{
+ u8 *jg_reloc, *jg_target, *prog = *pprog;
+ int pivot, err, jg_bytes = 1, cnt = 0;
+ s64 jg_offset;
+
+ if (a == b) {
+ /* Leaf node of recursion, i.e. not a range of indices
+ * anymore.
+ */
+ EMIT1(add_1mod(0x48, BPF_REG_3)); /* cmp rdx,func */
+ if (!is_simm32(progs[a]))
+ return -1;
+ EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3),
+ progs[a]);
+ err = emit_cond_near_jump(&prog, /* je func */
+ (void *)progs[a], prog,
+ X86_JE);
+ if (err)
+ return err;
+
+ err = emit_fallback_jump(&prog); /* jmp thunk/indirect */
+ if (err)
+ return err;
+
+ *pprog = prog;
+ return 0;
+ }
+
+ /* Not a leaf node, so we pivot, and recursively descend into
+ * the lower and upper ranges.
+ */
+ pivot = (b - a) / 2;
+ EMIT1(add_1mod(0x48, BPF_REG_3)); /* cmp rdx,func */
+ if (!is_simm32(progs[a + pivot]))
+ return -1;
+ EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3), progs[a + pivot]);
+
+ if (pivot > 2) { /* jg upper_part */
+ /* Require near jump. */
+ jg_bytes = 4;
+ EMIT2_off32(0x0F, X86_JG + 0x10, 0);
+ } else {
+ EMIT2(X86_JG, 0);
+ }
+ jg_reloc = prog;
+
+ err = emit_bpf_dispatcher(&prog, a, a + pivot, /* emit lower_part */
+ progs);
+ if (err)
+ return err;
+
+ /* From Intel 64 and IA-32 Architectures Optimization
+ * Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler
+ * Coding Rule 11: All branch targets should be 16-byte
+ * aligned.
+ */
+ jg_target = PTR_ALIGN(prog, 16);
+ if (jg_target != prog)
+ emit_nops(&prog, jg_target - prog);
+ jg_offset = prog - jg_reloc;
+ emit_code(jg_reloc - jg_bytes, jg_offset, jg_bytes);
+
+ err = emit_bpf_dispatcher(&prog, a + pivot + 1, /* emit upper_part */
+ b, progs);
+ if (err)
+ return err;
+
+ *pprog = prog;
+ return 0;
+}
+
+static int cmp_ips(const void *a, const void *b)
+{
+ const s64 *ipa = a;
+ const s64 *ipb = b;
+
+ if (*ipa > *ipb)
+ return 1;
+ if (*ipa < *ipb)
+ return -1;
+ return 0;
+}
+
+int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs)
+{
+ u8 *prog = image;
+
+ sort(funcs, num_funcs, sizeof(funcs[0]), cmp_ips, NULL);
+ return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs);
+}
+
struct x64_jit_data {
struct bpf_binary_header *header;
int *addrs;
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 35903f148be5..d467983e61bb 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -470,11 +470,69 @@ struct bpf_trampoline {
void *image;
u64 selector;
};
+
+#define BPF_DISPATCHER_MAX 48 /* Fits in 2048B */
+
+struct bpf_dispatcher_prog {
+ struct bpf_prog *prog;
+ refcount_t users;
+};
+
+struct bpf_dispatcher {
+ /* dispatcher mutex */
+ struct mutex mutex;
+ void *func;
+ struct bpf_dispatcher_prog progs[BPF_DISPATCHER_MAX];
+ int num_progs;
+ void *image;
+ u32 image_off;
+};
+
+static __always_inline unsigned int bpf_dispatcher_nopfunc(
+ const void *ctx,
+ const struct bpf_insn *insnsi,
+ unsigned int (*bpf_func)(const void *,
+ const struct bpf_insn *))
+{
+ return bpf_func(ctx, insnsi);
+}
#ifdef CONFIG_BPF_JIT
struct bpf_trampoline *bpf_trampoline_lookup(u64 key);
int bpf_trampoline_link_prog(struct bpf_prog *prog);
int bpf_trampoline_unlink_prog(struct bpf_prog *prog);
void bpf_trampoline_put(struct bpf_trampoline *tr);
+void *bpf_jit_alloc_exec_page(void);
+#define BPF_DISPATCHER_INIT(name) { \
+ .mutex = __MUTEX_INITIALIZER(name.mutex), \
+ .func = &name##func, \
+ .progs = {}, \
+ .num_progs = 0, \
+ .image = NULL, \
+ .image_off = 0 \
+}
+
+#define DEFINE_BPF_DISPATCHER(name) \
+ noinline unsigned int name##func( \
+ const void *ctx, \
+ const struct bpf_insn *insnsi, \
+ unsigned int (*bpf_func)(const void *, \
+ const struct bpf_insn *)) \
+ { \
+ return bpf_func(ctx, insnsi); \
+ } \
+ EXPORT_SYMBOL(name##func); \
+ struct bpf_dispatcher name = BPF_DISPATCHER_INIT(name);
+#define DECLARE_BPF_DISPATCHER(name) \
+ unsigned int name##func( \
+ const void *ctx, \
+ const struct bpf_insn *insnsi, \
+ unsigned int (*bpf_func)(const void *, \
+ const struct bpf_insn *)); \
+ extern struct bpf_dispatcher name;
+#define BPF_DISPATCHER_FUNC(name) name##func
+#define BPF_DISPATCHER_PTR(name) (&name)
+void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from,
+ struct bpf_prog *to);
#else
static inline struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
{
@@ -489,6 +547,13 @@ static inline int bpf_trampoline_unlink_prog(struct bpf_prog *prog)
return -ENOTSUPP;
}
static inline void bpf_trampoline_put(struct bpf_trampoline *tr) {}
+#define DEFINE_BPF_DISPATCHER(name)
+#define DECLARE_BPF_DISPATCHER(name)
+#define BPF_DISPATCHER_FUNC(name) bpf_dispatcher_nopfunc
+#define BPF_DISPATCHER_PTR(name) NULL
+static inline void bpf_dispatcher_change_prog(struct bpf_dispatcher *d,
+ struct bpf_prog *from,
+ struct bpf_prog *to) {}
#endif
struct bpf_func_info_aux {
@@ -940,6 +1005,8 @@ int btf_distill_func_proto(struct bpf_verifier_log *log,
int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog);
+struct bpf_prog *bpf_prog_by_id(u32 id);
+
#else /* !CONFIG_BPF_SYSCALL */
static inline struct bpf_prog *bpf_prog_get(u32 ufd)
{
@@ -1071,6 +1138,11 @@ static inline int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
static inline void bpf_map_put(struct bpf_map *map)
{
}
+
+static inline struct bpf_prog *bpf_prog_by_id(u32 id)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
#endif /* CONFIG_BPF_SYSCALL */
static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
diff --git a/include/linux/filter.h b/include/linux/filter.h
index a141cb07e76a..37ac7025031d 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -559,23 +559,26 @@ struct sk_filter {
DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
-#define BPF_PROG_RUN(prog, ctx) ({ \
- u32 ret; \
- cant_sleep(); \
- if (static_branch_unlikely(&bpf_stats_enabled_key)) { \
- struct bpf_prog_stats *stats; \
- u64 start = sched_clock(); \
- ret = (*(prog)->bpf_func)(ctx, (prog)->insnsi); \
- stats = this_cpu_ptr(prog->aux->stats); \
- u64_stats_update_begin(&stats->syncp); \
- stats->cnt++; \
- stats->nsecs += sched_clock() - start; \
- u64_stats_update_end(&stats->syncp); \
- } else { \
- ret = (*(prog)->bpf_func)(ctx, (prog)->insnsi); \
- } \
+#define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \
+ u32 ret; \
+ cant_sleep(); \
+ if (static_branch_unlikely(&bpf_stats_enabled_key)) { \
+ struct bpf_prog_stats *stats; \
+ u64 start = sched_clock(); \
+ ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \
+ stats = this_cpu_ptr(prog->aux->stats); \
+ u64_stats_update_begin(&stats->syncp); \
+ stats->cnt++; \
+ stats->nsecs += sched_clock() - start; \
+ u64_stats_update_end(&stats->syncp); \
+ } else { \
+ ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \
+ } \
ret; })
+#define BPF_PROG_RUN(prog, ctx) __BPF_PROG_RUN(prog, ctx, \
+ bpf_dispatcher_nopfunc)
+
#define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
struct bpf_skb_data_end {
@@ -699,6 +702,8 @@ static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
return res;
}
+DECLARE_BPF_DISPATCHER(bpf_dispatcher_xdp)
+
static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
struct xdp_buff *xdp)
{
@@ -708,9 +713,12 @@ static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
* already takes rcu_read_lock() when fetching the program, so
* it's not necessary here anymore.
*/
- return BPF_PROG_RUN(prog, xdp);
+ return __BPF_PROG_RUN(prog, xdp,
+ BPF_DISPATCHER_FUNC(bpf_dispatcher_xdp));
}
+void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
+
static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
{
return prog->len * sizeof(struct bpf_insn);
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 3f671bf617e8..d4f330351f87 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o
obj-$(CONFIG_BPF_SYSCALL) += disasm.o
obj-$(CONFIG_BPF_JIT) += trampoline.o
obj-$(CONFIG_BPF_SYSCALL) += btf.o
+obj-$(CONFIG_BPF_JIT) += dispatcher.o
ifeq ($(CONFIG_NET),y)
obj-$(CONFIG_BPF_SYSCALL) += devmap.o
obj-$(CONFIG_BPF_SYSCALL) += cpumap.o
diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c
new file mode 100644
index 000000000000..204ee61a3904
--- /dev/null
+++ b/kernel/bpf/dispatcher.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2019 Intel Corporation. */
+
+#include <linux/hash.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+
+/* The BPF dispatcher is a multiway branch code generator. The
+ * dispatcher is a mechanism to avoid the performance penalty of an
+ * indirect call, which is expensive when retpolines are enabled. A
+ * dispatch client registers a BPF program into the dispatcher, and if
+ * there is available room in the dispatcher a direct call to the BPF
+ * program will be generated. All calls to the BPF programs called via
+ * the dispatcher will then be a direct call, instead of an
+ * indirect. The dispatcher hijacks a trampoline function it via the
+ * __fentry__ of the trampoline. The trampoline function has the
+ * following signature:
+ *
+ * unsigned int trampoline(const void *ctx, const struct bpf_insn *insnsi,
+ * unsigned int (*bpf_func)(const void *,
+ * const struct bpf_insn *));
+ */
+
+static struct bpf_dispatcher_prog *bpf_dispatcher_find_prog(
+ struct bpf_dispatcher *d, struct bpf_prog *prog)
+{
+ int i;
+
+ for (i = 0; i < BPF_DISPATCHER_MAX; i++) {
+ if (prog == d->progs[i].prog)
+ return &d->progs[i];
+ }
+ return NULL;
+}
+
+static struct bpf_dispatcher_prog *bpf_dispatcher_find_free(
+ struct bpf_dispatcher *d)
+{
+ return bpf_dispatcher_find_prog(d, NULL);
+}
+
+static bool bpf_dispatcher_add_prog(struct bpf_dispatcher *d,
+ struct bpf_prog *prog)
+{
+ struct bpf_dispatcher_prog *entry;
+
+ if (!prog)
+ return false;
+
+ entry = bpf_dispatcher_find_prog(d, prog);
+ if (entry) {
+ refcount_inc(&entry->users);
+ return false;
+ }
+
+ entry = bpf_dispatcher_find_free(d);
+ if (!entry)
+ return false;
+
+ bpf_prog_inc(prog);
+ entry->prog = prog;
+ refcount_set(&entry->users, 1);
+ d->num_progs++;
+ return true;
+}
+
+static bool bpf_dispatcher_remove_prog(struct bpf_dispatcher *d,
+ struct bpf_prog *prog)
+{
+ struct bpf_dispatcher_prog *entry;
+
+ if (!prog)
+ return false;
+
+ entry = bpf_dispatcher_find_prog(d, prog);
+ if (!entry)
+ return false;
+
+ if (refcount_dec_and_test(&entry->users)) {
+ entry->prog = NULL;
+ bpf_prog_put(prog);
+ d->num_progs--;
+ return true;
+ }
+ return false;
+}
+
+int __weak arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs)
+{
+ return -ENOTSUPP;
+}
+
+static int bpf_dispatcher_prepare(struct bpf_dispatcher *d, void *image)
+{
+ s64 ips[BPF_DISPATCHER_MAX] = {}, *ipsp = &ips[0];
+ int i;
+
+ for (i = 0; i < BPF_DISPATCHER_MAX; i++) {
+ if (d->progs[i].prog)
+ *ipsp++ = (s64)(uintptr_t)d->progs[i].prog->bpf_func;
+ }
+ return arch_prepare_bpf_dispatcher(image, &ips[0], d->num_progs);
+}
+
+static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs)
+{
+ void *old, *new;
+ u32 noff;
+ int err;
+
+ if (!prev_num_progs) {
+ old = NULL;
+ noff = 0;
+ } else {
+ old = d->image + d->image_off;
+ noff = d->image_off ^ (PAGE_SIZE / 2);
+ }
+
+ new = d->num_progs ? d->image + noff : NULL;
+ if (new) {
+ if (bpf_dispatcher_prepare(d, new))
+ return;
+ }
+
+ err = bpf_arch_text_poke(d->func, BPF_MOD_JUMP, old, new);
+ if (err || !new)
+ return;
+
+ d->image_off = noff;
+}
+
+void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from,
+ struct bpf_prog *to)
+{
+ bool changed = false;
+ int prev_num_progs;
+
+ if (from == to)
+ return;
+
+ mutex_lock(&d->mutex);
+ if (!d->image) {
+ d->image = bpf_jit_alloc_exec_page();
+ if (!d->image)
+ goto out;
+ }
+
+ prev_num_progs = d->num_progs;
+ changed |= bpf_dispatcher_remove_prog(d, from);
+ changed |= bpf_dispatcher_add_prog(d, to);
+
+ if (!changed)
+ goto out;
+
+ bpf_dispatcher_update(d, prev_num_progs);
+out:
+ mutex_unlock(&d->mutex);
+}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 66b90eaf99fe..b08c362f4e02 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2338,17 +2338,12 @@ static int bpf_obj_get_next_id(const union bpf_attr *attr,
#define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
-static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
+struct bpf_prog *bpf_prog_by_id(u32 id)
{
struct bpf_prog *prog;
- u32 id = attr->prog_id;
- int fd;
-
- if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
- return -EINVAL;
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
+ if (!id)
+ return ERR_PTR(-ENOENT);
spin_lock_bh(&prog_idr_lock);
prog = idr_find(&prog_idr, id);
@@ -2357,7 +2352,22 @@ static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
else
prog = ERR_PTR(-ENOENT);
spin_unlock_bh(&prog_idr_lock);
+ return prog;
+}
+
+static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
+{
+ struct bpf_prog *prog;
+ u32 id = attr->prog_id;
+ int fd;
+
+ if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ prog = bpf_prog_by_id(id);
if (IS_ERR(prog))
return PTR_ERR(prog);
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 7e89f1f49d77..5ee301ddbd00 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -13,6 +13,22 @@ static struct hlist_head trampoline_table[TRAMPOLINE_TABLE_SIZE];
/* serializes access to trampoline_table */
static DEFINE_MUTEX(trampoline_mutex);
+void *bpf_jit_alloc_exec_page(void)
+{
+ void *image;
+
+ image = bpf_jit_alloc_exec(PAGE_SIZE);
+ if (!image)
+ return NULL;
+
+ set_vm_flush_reset_perms(image);
+ /* Keep image as writeable. The alternative is to keep flipping ro/rw
+ * everytime new program is attached or detached.
+ */
+ set_memory_x((long)image, 1);
+ return image;
+}
+
struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
{
struct bpf_trampoline *tr;
@@ -33,7 +49,7 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
goto out;
/* is_root was checked earlier. No need for bpf_jit_charge_modmem() */
- image = bpf_jit_alloc_exec(PAGE_SIZE);
+ image = bpf_jit_alloc_exec_page();
if (!image) {
kfree(tr);
tr = NULL;
@@ -47,12 +63,6 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
mutex_init(&tr->mutex);
for (i = 0; i < BPF_TRAMP_MAX; i++)
INIT_HLIST_HEAD(&tr->progs_hlist[i]);
-
- set_vm_flush_reset_perms(image);
- /* Keep image as writeable. The alternative is to keep flipping ro/rw
- * everytime new program is attached or detached.
- */
- set_memory_x((long)image, 1);
tr->image = image;
out:
mutex_unlock(&trampoline_mutex);
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 85c8cbbada92..5016c538d3ce 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -15,7 +15,7 @@
#include <trace/events/bpf_test_run.h>
static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat,
- u32 *retval, u32 *time)
+ u32 *retval, u32 *time, bool xdp)
{
struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = { NULL };
enum bpf_cgroup_storage_type stype;
@@ -41,7 +41,11 @@ static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat,
time_start = ktime_get_ns();
for (i = 0; i < repeat; i++) {
bpf_cgroup_storage_set(storage);
- *retval = BPF_PROG_RUN(prog, ctx);
+
+ if (xdp)
+ *retval = bpf_prog_run_xdp(prog, ctx);
+ else
+ *retval = BPF_PROG_RUN(prog, ctx);
if (signal_pending(current)) {
ret = -EINTR;
@@ -356,7 +360,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
ret = convert___skb_to_skb(skb, ctx);
if (ret)
goto out;
- ret = bpf_test_run(prog, skb, repeat, &retval, &duration);
+ ret = bpf_test_run(prog, skb, repeat, &retval, &duration, false);
if (ret)
goto out;
if (!is_l2) {
@@ -413,8 +417,8 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0);
xdp.rxq = &rxqueue->xdp_rxq;
-
- ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration);
+ bpf_prog_change_xdp(NULL, prog);
+ ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true);
if (ret)
goto out;
if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN ||
@@ -422,6 +426,7 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
size = xdp.data_end - xdp.data;
ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration);
out:
+ bpf_prog_change_xdp(prog, NULL);
kfree(data);
return ret;
}
diff --git a/net/core/dev.c b/net/core/dev.c
index 2c277b8aba38..255d3cf35360 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -8542,7 +8542,17 @@ static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op,
struct netlink_ext_ack *extack, u32 flags,
struct bpf_prog *prog)
{
+ bool non_hw = !(flags & XDP_FLAGS_HW_MODE);
+ struct bpf_prog *prev_prog = NULL;
struct netdev_bpf xdp;
+ int err;
+
+ if (non_hw) {
+ prev_prog = bpf_prog_by_id(__dev_xdp_query(dev, bpf_op,
+ XDP_QUERY_PROG));
+ if (IS_ERR(prev_prog))
+ prev_prog = NULL;
+ }
memset(&xdp, 0, sizeof(xdp));
if (flags & XDP_FLAGS_HW_MODE)
@@ -8553,7 +8563,14 @@ static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op,
xdp.flags = flags;
xdp.prog = prog;
- return bpf_op(dev, &xdp);
+ err = bpf_op(dev, &xdp);
+ if (!err && non_hw)
+ bpf_prog_change_xdp(prev_prog, prog);
+
+ if (prev_prog)
+ bpf_prog_put(prev_prog);
+
+ return err;
}
static void dev_xdp_uninstall(struct net_device *dev)
diff --git a/net/core/filter.c b/net/core/filter.c
index f1e703eed3d2..a411f7835dee 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -8940,3 +8940,11 @@ const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
const struct bpf_prog_ops sk_reuseport_prog_ops = {
};
#endif /* CONFIG_INET */
+
+DEFINE_BPF_DISPATCHER(bpf_dispatcher_xdp)
+
+void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
+{
+ bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(bpf_dispatcher_xdp),
+ prev_prog, prog);
+}
diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_perf.c b/tools/testing/selftests/bpf/prog_tests/xdp_perf.c
new file mode 100644
index 000000000000..7185bee16fe4
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_perf.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+
+void test_xdp_perf(void)
+{
+ const char *file = "./xdp_dummy.o";
+ __u32 duration, retval, size;
+ struct bpf_object *obj;
+ char in[128], out[128];
+ int err, prog_fd;
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ err = bpf_prog_test_run(prog_fd, 1000000, &in[0], 128,
+ out, &size, &retval, &duration);
+
+ CHECK(err || retval != XDP_PASS || size != 128,
+ "xdp-perf",
+ "err %d errno %d retval %d size %d\n",
+ err, errno, retval, size);
+
+ bpf_object__close(obj);
+}