diff mbox series

[bpf-next,v3,1/3] selftests/bpf: Allow building with extra flags

Message ID 6cb7d34d0ff257deaf5bb818ac4bce3c95994d29.1730449390.git.vmalik@redhat.com (mailing list archive)
State Accepted
Commit 9a28559932d2a4d043d3f3f68ea0cb911277b8ce
Delegated to: BPF
Headers show
Series selftests/bpf: Improve building with extra | expand

Checks

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bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-39 success Logs for x86_64-llvm-18 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-37 success Logs for x86_64-llvm-18 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-18
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netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5 this patch: 5
netdev/build_tools success Errors and warnings before: 0 (+0) this patch: 0 (+0)
netdev/cc_maintainers warning 1 maintainers not CCed: linux-kselftest@vger.kernel.org
netdev/build_clang success Errors and warnings before: 4 this patch: 4
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 85 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-VM_Test-4 success Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for aarch64-gcc / test (test_verifier, false, 360) / test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-12 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-6 success Logs for aarch64-gcc / test (test_maps, false, 360) / test_maps on aarch64 with gcc
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bpf/vmtest-bpf-next-VM_Test-33 success Logs for x86_64-llvm-17 / veristat
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bpf/vmtest-bpf-next-VM_Test-16 success Logs for s390x-gcc / veristat
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bpf/vmtest-bpf-next-VM_Test-18 success Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-27 success Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-28 success Logs for x86_64-llvm-17 / build-release / build for x86_64 with llvm-17-O2
bpf/vmtest-bpf-next-VM_Test-17 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-14 success Logs for s390x-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-15 success Logs for s390x-gcc / test (test_verifier, false, 360) / test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-13 success Logs for s390x-gcc / test (test_progs, false, 360) / test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for x86_64-gcc / test (test_maps, false, 360) / test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-22 success Logs for x86_64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-23 success Logs for x86_64-gcc / test (test_progs_no_alu32_parallel, true, 30) / test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-36 success Logs for x86_64-llvm-18 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-29 success Logs for x86_64-llvm-17 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-21 success Logs for x86_64-gcc / test (test_progs, false, 360) / test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-26 success Logs for x86_64-gcc / veristat / veristat on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-24 success Logs for x86_64-gcc / test (test_progs_parallel, true, 30) / test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-31 success Logs for x86_64-llvm-17 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-30 success Logs for x86_64-llvm-17 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-32 success Logs for x86_64-llvm-17 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-25 success Logs for x86_64-gcc / test (test_verifier, false, 360) / test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-40 success Logs for x86_64-llvm-18 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-18
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Commit Message

Viktor Malik Nov. 1, 2024, 8:27 a.m. UTC 
In order to specify extra compilation or linking flags to BPF selftests,
it is possible to set EXTRA_CFLAGS and EXTRA_LDFLAGS from the command
line. The problem is that they are not propagated to sub-make calls
(runqslower, bpftool, libbpf) and in the better case are not applied, in
the worse case cause the entire build fail.

Propagate EXTRA_CFLAGS and EXTRA_LDFLAGS to the sub-makes.

This, for instance, allows to build selftests as PIE with

    $ make EXTRA_CFLAGS='-fPIE' EXTRA_LDFLAGS='-pie'

Without this change, the command would fail because libbpf.a would not
be built with -fPIE and other PIE binaries would not link against it.

The only problem is that we have to explicitly provide empty
EXTRA_CFLAGS='' and EXTRA_LDFLAGS='' to the builds of kernel modules as
we don't want to build modules with flags used for userspace (the above
example would fail as kernel doesn't support PIE).

Signed-off-by: Viktor Malik <vmalik@redhat.com>
---
 tools/testing/selftests/bpf/Makefile | 34 +++++++++++++++++++---------
 1 file changed, 23 insertions(+), 11 deletions(-)

Comments

Andrii Nakryiko Nov. 1, 2024, 7:34 p.m. UTC | #1 
On Fri, Nov 1, 2024 at 1:29 AM Viktor Malik <vmalik@redhat.com> wrote:
>
> In order to specify extra compilation or linking flags to BPF selftests,
> it is possible to set EXTRA_CFLAGS and EXTRA_LDFLAGS from the command
> line. The problem is that they are not propagated to sub-make calls
> (runqslower, bpftool, libbpf) and in the better case are not applied, in
> the worse case cause the entire build fail.
>
> Propagate EXTRA_CFLAGS and EXTRA_LDFLAGS to the sub-makes.
>
> This, for instance, allows to build selftests as PIE with
>
>     $ make EXTRA_CFLAGS='-fPIE' EXTRA_LDFLAGS='-pie'
>
> Without this change, the command would fail because libbpf.a would not
> be built with -fPIE and other PIE binaries would not link against it.
>
> The only problem is that we have to explicitly provide empty
> EXTRA_CFLAGS='' and EXTRA_LDFLAGS='' to the builds of kernel modules as
> we don't want to build modules with flags used for userspace (the above
> example would fail as kernel doesn't support PIE).
>
> Signed-off-by: Viktor Malik <vmalik@redhat.com>
> ---
>  tools/testing/selftests/bpf/Makefile | 34 +++++++++++++++++++---------
>  1 file changed, 23 insertions(+), 11 deletions(-)
>

Ok, so this will conflict with Toke's [0]. Who should go first? :)

And given you guys touch these more obscure parts of BPF selftests
Makefile, I'd really appreciate it if you can help reviewing them for
each other :)


  [0] https://patchwork.kernel.org/project/netdevbpf/patch/20241031-bpf-selftests-mod-compile-v1-1-1a63af2385f1@redhat.com/

[...]
Toke Høiland-Jørgensen Nov. 4, 2024, 1:43 p.m. UTC | #2 
Andrii Nakryiko <andrii.nakryiko@gmail.com> writes:

> On Fri, Nov 1, 2024 at 1:29 AM Viktor Malik <vmalik@redhat.com> wrote:
>>
>> In order to specify extra compilation or linking flags to BPF selftests,
>> it is possible to set EXTRA_CFLAGS and EXTRA_LDFLAGS from the command
>> line. The problem is that they are not propagated to sub-make calls
>> (runqslower, bpftool, libbpf) and in the better case are not applied, in
>> the worse case cause the entire build fail.
>>
>> Propagate EXTRA_CFLAGS and EXTRA_LDFLAGS to the sub-makes.
>>
>> This, for instance, allows to build selftests as PIE with
>>
>>     $ make EXTRA_CFLAGS='-fPIE' EXTRA_LDFLAGS='-pie'
>>
>> Without this change, the command would fail because libbpf.a would not
>> be built with -fPIE and other PIE binaries would not link against it.
>>
>> The only problem is that we have to explicitly provide empty
>> EXTRA_CFLAGS='' and EXTRA_LDFLAGS='' to the builds of kernel modules as
>> we don't want to build modules with flags used for userspace (the above
>> example would fail as kernel doesn't support PIE).
>>
>> Signed-off-by: Viktor Malik <vmalik@redhat.com>
>> ---
>>  tools/testing/selftests/bpf/Makefile | 34 +++++++++++++++++++---------
>>  1 file changed, 23 insertions(+), 11 deletions(-)
>>
>
> Ok, so this will conflict with Toke's [0]. Who should go first? :)

I'm OK with rebasing on top of Viktor's patch :)
>
> And given you guys touch these more obscure parts of BPF selftests
> Makefile, I'd really appreciate it if you can help reviewing them for
> each other :)

Sure, can do!

-Toke
Toke Høiland-Jørgensen Nov. 4, 2024, 2:03 p.m. UTC | #3 
Viktor Malik <vmalik@redhat.com> writes:

> In order to specify extra compilation or linking flags to BPF selftests,
> it is possible to set EXTRA_CFLAGS and EXTRA_LDFLAGS from the command
> line. The problem is that they are not propagated to sub-make calls
> (runqslower, bpftool, libbpf) and in the better case are not applied, in
> the worse case cause the entire build fail.
>
> Propagate EXTRA_CFLAGS and EXTRA_LDFLAGS to the sub-makes.
>
> This, for instance, allows to build selftests as PIE with
>
>     $ make EXTRA_CFLAGS='-fPIE' EXTRA_LDFLAGS='-pie'
>
> Without this change, the command would fail because libbpf.a would not
> be built with -fPIE and other PIE binaries would not link against it.
>
> The only problem is that we have to explicitly provide empty
> EXTRA_CFLAGS='' and EXTRA_LDFLAGS='' to the builds of kernel modules as
> we don't want to build modules with flags used for userspace (the above
> example would fail as kernel doesn't support PIE).
>
> Signed-off-by: Viktor Malik <vmalik@redhat.com>

That last bit is a bit ugly, but I couldn't think of a better way of
doing it, so with that:

Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Andrii Nakryiko Nov. 6, 2024, 8:37 p.m. UTC | #4 
On Mon, Nov 4, 2024 at 5:43 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote:
>
> Andrii Nakryiko <andrii.nakryiko@gmail.com> writes:
>
> > On Fri, Nov 1, 2024 at 1:29 AM Viktor Malik <vmalik@redhat.com> wrote:
> >>
> >> In order to specify extra compilation or linking flags to BPF selftests,
> >> it is possible to set EXTRA_CFLAGS and EXTRA_LDFLAGS from the command
> >> line. The problem is that they are not propagated to sub-make calls
> >> (runqslower, bpftool, libbpf) and in the better case are not applied, in
> >> the worse case cause the entire build fail.
> >>
> >> Propagate EXTRA_CFLAGS and EXTRA_LDFLAGS to the sub-makes.
> >>
> >> This, for instance, allows to build selftests as PIE with
> >>
> >>     $ make EXTRA_CFLAGS='-fPIE' EXTRA_LDFLAGS='-pie'
> >>
> >> Without this change, the command would fail because libbpf.a would not
> >> be built with -fPIE and other PIE binaries would not link against it.
> >>
> >> The only problem is that we have to explicitly provide empty
> >> EXTRA_CFLAGS='' and EXTRA_LDFLAGS='' to the builds of kernel modules as
> >> we don't want to build modules with flags used for userspace (the above
> >> example would fail as kernel doesn't support PIE).
> >>
> >> Signed-off-by: Viktor Malik <vmalik@redhat.com>
> >> ---
> >>  tools/testing/selftests/bpf/Makefile | 34 +++++++++++++++++++---------
> >>  1 file changed, 23 insertions(+), 11 deletions(-)
> >>
> >
> > Ok, so this will conflict with Toke's [0]. Who should go first? :)
>
> I'm OK with rebasing on top of Viktor's patch :)

Ok, then. Thanks for the review! I've applied this patch to
bpf-next/master as well. Please rebase and resend your change.

> >
> > And given you guys touch these more obscure parts of BPF selftests
> > Makefile, I'd really appreciate it if you can help reviewing them for
> > each other :)
>
> Sure, can do!
>
> -Toke
>
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index a226d0647c4e..3b43d7db8d2c 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -295,25 +295,33 @@  $(OUTPUT)/sign-file: ../../../../scripts/sign-file.c
 $(OUTPUT)/bpf_testmod.ko: $(VMLINUX_BTF) $(RESOLVE_BTFIDS) $(wildcard bpf_testmod/Makefile bpf_testmod/*.[ch])
 	$(call msg,MOD,,$@)
 	$(Q)$(RM) bpf_testmod/bpf_testmod.ko # force re-compilation
-	$(Q)$(MAKE) $(submake_extras) RESOLVE_BTFIDS=$(RESOLVE_BTFIDS) -C bpf_testmod
+	$(Q)$(MAKE) $(submake_extras) -C bpf_testmod \
+		RESOLVE_BTFIDS=$(RESOLVE_BTFIDS)     \
+		EXTRA_CFLAGS='' EXTRA_LDFLAGS=''
 	$(Q)cp bpf_testmod/bpf_testmod.ko $@
 
 $(OUTPUT)/bpf_test_no_cfi.ko: $(VMLINUX_BTF) $(RESOLVE_BTFIDS) $(wildcard bpf_test_no_cfi/Makefile bpf_test_no_cfi/*.[ch])
 	$(call msg,MOD,,$@)
 	$(Q)$(RM) bpf_test_no_cfi/bpf_test_no_cfi.ko # force re-compilation
-	$(Q)$(MAKE) $(submake_extras) RESOLVE_BTFIDS=$(RESOLVE_BTFIDS) -C bpf_test_no_cfi
+	$(Q)$(MAKE) $(submake_extras) -C bpf_test_no_cfi \
+		RESOLVE_BTFIDS=$(RESOLVE_BTFIDS)	 \
+		EXTRA_CFLAGS='' EXTRA_LDFLAGS=''
 	$(Q)cp bpf_test_no_cfi/bpf_test_no_cfi.ko $@
 
 $(OUTPUT)/bpf_test_modorder_x.ko: $(VMLINUX_BTF) $(RESOLVE_BTFIDS) $(wildcard bpf_test_modorder_x/Makefile bpf_test_modorder_x/*.[ch])
 	$(call msg,MOD,,$@)
 	$(Q)$(RM) bpf_test_modorder_x/bpf_test_modorder_x.ko # force re-compilation
-	$(Q)$(MAKE) $(submake_extras) RESOLVE_BTFIDS=$(RESOLVE_BTFIDS) -C bpf_test_modorder_x
+	$(Q)$(MAKE) $(submake_extras) -C bpf_test_modorder_x \
+		RESOLVE_BTFIDS=$(RESOLVE_BTFIDS)	     \
+		EXTRA_CFLAGS='' EXTRA_LDFLAGS=''
 	$(Q)cp bpf_test_modorder_x/bpf_test_modorder_x.ko $@
 
 $(OUTPUT)/bpf_test_modorder_y.ko: $(VMLINUX_BTF) $(RESOLVE_BTFIDS) $(wildcard bpf_test_modorder_y/Makefile bpf_test_modorder_y/*.[ch])
 	$(call msg,MOD,,$@)
 	$(Q)$(RM) bpf_test_modorder_y/bpf_test_modorder_y.ko # force re-compilation
-	$(Q)$(MAKE) $(submake_extras) RESOLVE_BTFIDS=$(RESOLVE_BTFIDS) -C bpf_test_modorder_y
+	$(Q)$(MAKE) $(submake_extras) -C bpf_test_modorder_y \
+		RESOLVE_BTFIDS=$(RESOLVE_BTFIDS)	     \
+		EXTRA_CFLAGS='' EXTRA_LDFLAGS=''
 	$(Q)cp bpf_test_modorder_y/bpf_test_modorder_y.ko $@
 
 
@@ -333,8 +341,8 @@  $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) $(RUNQSLOWER_OUTPUT)
 		    BPFTOOL_OUTPUT=$(HOST_BUILD_DIR)/bpftool/		       \
 		    BPFOBJ_OUTPUT=$(BUILD_DIR)/libbpf/			       \
 		    BPFOBJ=$(BPFOBJ) BPF_INCLUDE=$(INCLUDE_DIR)		       \
-		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(SAN_CFLAGS)'	       \
-		    EXTRA_LDFLAGS='$(SAN_LDFLAGS)' &&			       \
+		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(SAN_CFLAGS) $(EXTRA_CFLAGS)' \
+		    EXTRA_LDFLAGS='$(SAN_LDFLAGS) $(EXTRA_LDFLAGS)' &&	       \
 		    cp $(RUNQSLOWER_OUTPUT)runqslower $@
 
 TEST_GEN_PROGS_EXTENDED += $(TRUNNER_BPFTOOL)
@@ -367,7 +375,8 @@  $(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile)    \
 		    $(HOST_BPFOBJ) | $(HOST_BUILD_DIR)/bpftool
 	$(Q)$(MAKE) $(submake_extras)  -C $(BPFTOOLDIR)			       \
 		    ARCH= CROSS_COMPILE= CC="$(HOSTCC)" LD="$(HOSTLD)" 	       \
-		    EXTRA_CFLAGS='-g $(OPT_FLAGS)'			       \
+		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(EXTRA_CFLAGS)'	       \
+		    EXTRA_LDFLAGS='$(EXTRA_LDFLAGS)'			       \
 		    OUTPUT=$(HOST_BUILD_DIR)/bpftool/			       \
 		    LIBBPF_OUTPUT=$(HOST_BUILD_DIR)/libbpf/		       \
 		    LIBBPF_DESTDIR=$(HOST_SCRATCH_DIR)/			       \
@@ -378,7 +387,8 @@  $(CROSS_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile)	\
 		    $(BPFOBJ) | $(BUILD_DIR)/bpftool
 	$(Q)$(MAKE) $(submake_extras)  -C $(BPFTOOLDIR)				\
 		    ARCH=$(ARCH) CROSS_COMPILE=$(CROSS_COMPILE)			\
-		    EXTRA_CFLAGS='-g $(OPT_FLAGS)'				\
+		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(EXTRA_CFLAGS)'		\
+		    EXTRA_LDFLAGS='$(EXTRA_LDFLAGS)'				\
 		    OUTPUT=$(BUILD_DIR)/bpftool/				\
 		    LIBBPF_OUTPUT=$(BUILD_DIR)/libbpf/				\
 		    LIBBPF_DESTDIR=$(SCRATCH_DIR)/				\
@@ -401,8 +411,8 @@  $(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile)		       \
 	   $(APIDIR)/linux/bpf.h					       \
 	   | $(BUILD_DIR)/libbpf
 	$(Q)$(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \
-		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(SAN_CFLAGS)'	       \
-		    EXTRA_LDFLAGS='$(SAN_LDFLAGS)'			       \
+		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(SAN_CFLAGS) $(EXTRA_CFLAGS)' \
+		    EXTRA_LDFLAGS='$(SAN_LDFLAGS) $(EXTRA_LDFLAGS)'	       \
 		    DESTDIR=$(SCRATCH_DIR) prefix= all install_headers
 
 ifneq ($(BPFOBJ),$(HOST_BPFOBJ))
@@ -410,7 +420,9 @@  $(HOST_BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile)		       \
 		$(APIDIR)/linux/bpf.h					       \
 		| $(HOST_BUILD_DIR)/libbpf
 	$(Q)$(MAKE) $(submake_extras) -C $(BPFDIR)                             \
-		    EXTRA_CFLAGS='-g $(OPT_FLAGS)' ARCH= CROSS_COMPILE=	       \
+		    ARCH= CROSS_COMPILE=				       \
+		    EXTRA_CFLAGS='-g $(OPT_FLAGS) $(EXTRA_CFLAGS)'	       \
+		    EXTRA_LDFLAGS='$(EXTRA_LDFLAGS)'			       \
 		    OUTPUT=$(HOST_BUILD_DIR)/libbpf/			       \
 		    CC="$(HOSTCC)" LD="$(HOSTLD)"			       \
 		    DESTDIR=$(HOST_SCRATCH_DIR)/ prefix= all install_headers