diff mbox series

[v6,2/2] bpftool: Align bpf_load_and_run_opts insns and data

Message ID 20231007044439.25171-2-irogers@google.com (mailing list archive)
State Accepted
Commit 1be84ca53ca0421c781f9ec007cd8bccbb58f763
Delegated to: BPF
Headers show
Series [v6,1/2] bpftool: Align output skeleton ELF code | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-0 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-4 success Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-2 success Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-1 success Logs for build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-3 success Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-5 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-6 success Logs for test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-7 success Logs for test_maps on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-8 success Logs for test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for test_maps on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-21 success Logs for test_progs_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-13 success Logs for test_progs on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-18 success Logs for test_progs_no_alu32_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-17 success Logs for test_progs_no_alu32 on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-10 success Logs for test_progs on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-26 success Logs for test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-12 success Logs for test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-19 success Logs for test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for test_progs_no_alu32_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-24 success Logs for test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-22 success Logs for test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-14 success Logs for test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-25 success Logs for test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-15 success Logs for test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-23 success Logs for test_progs_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-28 success Logs for veristat
bpf/vmtest-bpf-next-VM_Test-27 success Logs for test_verifier on x86_64 with llvm-16

Commit Message

Ian Rogers Oct. 7, 2023, 4:44 a.m. UTC 
A C string lacks alignment so use aligned arrays to avoid potential
alignment problems. Switch to using sizeof (less 1 for the \0
terminator) rather than a hardcode size constant.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
---
 tools/bpf/bpftool/gen.c | 43 ++++++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 20 deletions(-)
diff mbox series

Patch

diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c
index 882bf8e6e70e..ee3ce2b8000d 100644
--- a/tools/bpf/bpftool/gen.c
+++ b/tools/bpf/bpftool/gen.c
@@ -708,17 +708,22 @@  static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h
 
 		codegen("\
 		\n\
-			skel->%1$s = skel_prep_map_data((void *)\"\\	    \n\
-		", ident);
+			{						    \n\
+				static const char data[] __attribute__((__aligned__(8))) = \"\\\n\
+		");
 		mmap_data = bpf_map__initial_value(map, &mmap_size);
 		print_hex(mmap_data, mmap_size);
 		codegen("\
 		\n\
-		\", %1$zd, %2$zd);					    \n\
-			if (!skel->%3$s)				    \n\
-				goto cleanup;				    \n\
-			skel->maps.%3$s.initial_value = (__u64) (long) skel->%3$s;\n\
-		", bpf_map_mmap_sz(map), mmap_size, ident);
+		\";							    \n\
+									    \n\
+				skel->%1$s = skel_prep_map_data((void *)data, %2$zd,\n\
+								sizeof(data) - 1);\n\
+				if (!skel->%1$s)			    \n\
+					goto cleanup;			    \n\
+				skel->maps.%1$s.initial_value = (__u64) (long) skel->%1$s;\n\
+			}						    \n\
+			", ident, bpf_map_mmap_sz(map));
 	}
 	codegen("\
 		\n\
@@ -733,32 +738,30 @@  static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h
 		{							    \n\
 			struct bpf_load_and_run_opts opts = {};		    \n\
 			int err;					    \n\
-									    \n\
-			opts.ctx = (struct bpf_loader_ctx *)skel;	    \n\
-			opts.data_sz = %2$d;				    \n\
-			opts.data = (void *)\"\\			    \n\
+			static const char opts_data[] __attribute__((__aligned__(8))) = \"\\\n\
 		",
-		obj_name, opts.data_sz);
+		obj_name);
 	print_hex(opts.data, opts.data_sz);
 	codegen("\
 		\n\
 		\";							    \n\
+			static const char opts_insn[] __attribute__((__aligned__(8))) = \"\\\n\
 		");
-
-	codegen("\
-		\n\
-			opts.insns_sz = %d;				    \n\
-			opts.insns = (void *)\"\\			    \n\
-		",
-		opts.insns_sz);
 	print_hex(opts.insns, opts.insns_sz);
 	codegen("\
 		\n\
 		\";							    \n\
+									    \n\
+			opts.ctx = (struct bpf_loader_ctx *)skel;	    \n\
+			opts.data_sz = sizeof(opts_data) - 1;		    \n\
+			opts.data = (void *)opts_data;			    \n\
+			opts.insns_sz = sizeof(opts_insn) - 1;		    \n\
+			opts.insns = (void *)opts_insn;			    \n\
+									    \n\
 			err = bpf_load_and_run(&opts);			    \n\
 			if (err < 0)					    \n\
 				return err;				    \n\
-		", obj_name);
+		");
 	bpf_object__for_each_map(map, obj) {
 		const char *mmap_flags;