[PATCH v3 5/5] powerpc/bpf: use patch_instructions()

[Hari Bathini]

Use the newly introduced patch_instructions() that handles patching
multiple instructions with one call. This improves speed of exectution
for JIT'ing bpf programs.

Without this patch (on a POWER9 lpar):

  # time modprobe test_bpf
  real    2m59.681s
  user    0m0.000s
  sys     1m44.160s
  #

With this patch (on a POWER9 lpar):

  # time modprobe test_bpf
  real    0m5.013s
  user    0m0.000s
  sys     0m4.216s
  #

Signed-off-by: Hari Bathini <hbath...@linux.ibm.com>
---
 arch/powerpc/net/bpf_jit_comp.c | 30 ++++--------------------------
 1 file changed, 4 insertions(+), 26 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index c60d7570e05d..1e5000d18321 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -26,28 +26,6 @@ static void bpf_jit_fill_ill_insns(void *area, unsigned int 
size)
        memset32(area, BREAKPOINT_INSTRUCTION, size / 4);
 }
 
-/*
- * Patch 'len' bytes of instructions from opcode to addr, one instruction
- * at a time. Returns addr on success. ERR_PTR(-EINVAL), otherwise.
- */
-static void *bpf_patch_instructions(void *addr, void *opcode, size_t len, bool 
fill_insn)
-{
-       while (len > 0) {
-               ppc_inst_t insn = ppc_inst_read(opcode);
-               int ilen = ppc_inst_len(insn);
-
-               if (patch_instruction(addr, insn))
-                       return ERR_PTR(-EINVAL);
-
-               len -= ilen;
-               addr = addr + ilen;
-               if (!fill_insn)
-                       opcode = opcode + ilen;
-       }
-
-       return addr;
-}
-
 int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx, int 
tmp_reg, long exit_addr)
 {
        if (!exit_addr || is_offset_in_branch_range(exit_addr - (ctx->idx * 
4))) {
@@ -330,16 +308,16 @@ int bpf_add_extable_entry(struct bpf_prog *fp, u32 
*image, u32 *fimage, int pass
 
 void *bpf_arch_text_copy(void *dst, void *src, size_t len)
 {
-       void *ret;
+       int err;
 
        if (WARN_ON_ONCE(core_kernel_text((unsigned long)dst)))
                return ERR_PTR(-EINVAL);
 
        mutex_lock(&text_mutex);
-       ret = bpf_patch_instructions(dst, src, len, false);
+       err = patch_instructions(dst, src, len, false);
        mutex_unlock(&text_mutex);
 
-       return ret;
+       return err ? ERR_PTR(err) : dst;
 }
 
 int bpf_arch_text_invalidate(void *dst, size_t len)
@@ -351,7 +329,7 @@ int bpf_arch_text_invalidate(void *dst, size_t len)
                return -EINVAL;
 
        mutex_lock(&text_mutex);
-       ret = IS_ERR(bpf_patch_instructions(dst, &insn, len, true));
+       ret = patch_instructions(dst, &insn, len, true);
        mutex_unlock(&text_mutex);
 
        return ret;
-- 
2.41.0