s390/bpf,jit: improve code generation

Make use of new immediate instructions that came with the
extended immediate and general instruction extension facilities.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 37 insertions, 4 deletions

diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index b07aa3dc5ee..f57f0c335b1 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -10,6 +10,7 @@
 #include <linux/filter.h>
 #include <asm/cacheflush.h>
 #include <asm/processor.h>
+#include <asm/facility.h>
 
 /*
  * Conventions:
@@ -114,6 +115,12 @@ struct bpf_jit {
         EMIT6(op1 | __disp, op2);                       \
 })
 
+#define EMIT6_IMM(op, imm)                              \
+({                                                      \
+        unsigned int __imm = (imm);                     \
+        EMIT6(op | (__imm >> 16), __imm & 0xffff);      \
+})
+
 #define EMIT_CONST(val)                                 \
 ({                                                      \
         unsigned int ret;                               \
@@ -276,6 +283,9 @@ static int bpf_jit_insn(struct bpf_jit *jit, struct sock_filter *filter,
                 if (K <= 16383)
                         /* ahi %r5,<K> */
                         EMIT4_IMM(0xa75a0000, K);
+                else if (test_facility(21))
+                        /* alfi %r5,<K> */
+                        EMIT6_IMM(0xc25b0000, K);
                 else
                         /* a %r5,<d(K)>(%r13) */
                         EMIT4_DISP(0x5a50d000, EMIT_CONST(K));
@@ -291,6 +301,9 @@ static int bpf_jit_insn(struct bpf_jit *jit, struct sock_filter *filter,
                 if (K <= 16384)
                         /* ahi %r5,-K */
                         EMIT4_IMM(0xa75a0000, -K);
+                else if (test_facility(21))
+                        /* alfi %r5,-K */
+                        EMIT6_IMM(0xc25b0000, -K);
                 else
                         /* s %r5,<d(K)>(%r13) */
                         EMIT4_DISP(0x5b50d000, EMIT_CONST(K));
@@ -304,6 +317,9 @@ static int bpf_jit_insn(struct bpf_jit *jit, struct sock_filter *filter,
                 if (K <= 16383)
                         /* mhi %r5,K */
                         EMIT4_IMM(0xa75c0000, K);
+                else if (test_facility(34))
+                        /* msfi %r5,<K> */
+                        EMIT6_IMM(0xc2510000, K);
                 else
                         /* ms %r5,<d(K)>(%r13) */
                         EMIT4_DISP(0x7150d000, EMIT_CONST(K));
@@ -331,8 +347,12 @@ static int bpf_jit_insn(struct bpf_jit *jit, struct sock_filter *filter,
                 EMIT2(0x145c);
                 break;
         case BPF_S_ALU_AND_K: /* A &= K */
-                /* n %r5,<d(K)>(%r13) */
-                EMIT4_DISP(0x5450d000, EMIT_CONST(K));
+                if (test_facility(21))
+                        /* nilf %r5,<K> */
+                        EMIT6_IMM(0xc05b0000, K);
+                else
+                        /* n %r5,<d(K)>(%r13) */
+                        EMIT4_DISP(0x5450d000, EMIT_CONST(K));
                 break;
         case BPF_S_ALU_OR_X: /* A |= X */
                 jit->seen |= SEEN_XREG;
@@ -340,8 +360,12 @@ static int bpf_jit_insn(struct bpf_jit *jit, struct sock_filter *filter,
                 EMIT2(0x165c);
                 break;
         case BPF_S_ALU_OR_K: /* A |= K */
-                /* o %r5,<d(K)>(%r13) */
-                EMIT4_DISP(0x5650d000, EMIT_CONST(K));
+                if (test_facility(21))
+                        /* oilf %r5,<K> */
+                        EMIT6_IMM(0xc05d0000, K);
+                else
+                        /* o %r5,<d(K)>(%r13) */
+                        EMIT4_DISP(0x5650d000, EMIT_CONST(K));
                 break;
         case BPF_S_ALU_LSH_X: /* A <<= X; */
                 jit->seen |= SEEN_XREG;
@@ -386,6 +410,9 @@ kbranch:	/* Emit compare if the branch targets are different */
                         if (K <= 16383)
                                 /* chi %r5,<K> */
                                 EMIT4_IMM(0xa75e0000, K);
+                        else if (test_facility(21))
+                                /* clfi %r5,<K> */
+                                EMIT6_IMM(0xc25f0000, K);
                         else
                                 /* c %r5,<d(K)>(%r13) */
                                 EMIT4_DISP(0x5950d000, EMIT_CONST(K));
@@ -508,6 +535,9 @@ call_fn:	/* lg %r1,<d(function)>(%r13) */
                 if (K <= 16383)
                         /* lhi %r5,K */
                         EMIT4_IMM(0xa7580000, K);
+                else if (test_facility(21))
+                        /* llilf %r5,<K> */
+                        EMIT6_IMM(0xc05f0000, K);
                 else
                         /* l %r5,<d(K)>(%r13) */
                         EMIT4_DISP(0x5850d000, EMIT_CONST(K));
@@ -517,6 +547,9 @@ call_fn:	/* lg %r1,<d(function)>(%r13) */
                 if (K <= 16383)
                         /* lhi %r12,<K> */
                         EMIT4_IMM(0xa7c80000, K);
+                else if (test_facility(21))
+                        /* llilf %r12,<K> */
+                        EMIT6_IMM(0xc0cf0000, K);
                 else
                         /* l %r12,<d(K)>(%r13) */
                         EMIT4_DISP(0x58c0d000, EMIT_CONST(K));