Changes since v1:
* check_config.sh now invokes the compiler via the Makefile's ($CC),
thanks to Jason Gunthorpe for calling that out.
* Removed a misleading sentence from patch #6, as identified by Ira
Weiny.
* Removed a forward-looking sentence, about using -lpthread in
gup_test.c soon, from the commit message in patch #4, since I'm not yet
sure if my local pthread-based stress tests are actually worthwhile or
not.
Original cover letter, still accurate at this point:
This is based on the latest mmotm.
Summary: This series provides two main things, and a number of smaller
supporting goodies. The two main points are:
1) Add a new sub-test to gup_test, which in turn is a renamed version of
gup_benchmark. This sub-test allows nicer testing of dump_pages(), at
least on user-space pages.
For quite a while, I was doing a quick hack to gup_test.c whenever I
wanted to try out changes to dump_page(). Then Matthew Wilcox asked me
what I meant when I said "I used my dump_page() unit test", and I
realized that it might be nice to check in a polished up version of
that.
Details about how it works and how to use it are in the commit
description for patch #6.
2) Fixes a limitation of hmm-tests: these tests are incredibly useful,
but only if people actually build and run them. And it turns out that
libhugetlbfs is a little too effective at throwing a wrench in the
works, there. So I've added a little configuration check that removes
just two of the 21 hmm-tests, if libhugetlbfs is not available.
Further details in the commit description of patch #8.
Other smaller things that this series does:
a) Remove code duplication by creating gup_test.h.
b) Clear up the sub-test organization, and their invocation within
run_vmtests.sh.
c) Other minor assorted improvements.
John Hubbard (8):
mm/gup_benchmark: rename to mm/gup_test
selftests/vm: use a common gup_test.h
selftests/vm: rename run_vmtests --> run_vmtests.sh
selftests/vm: minor cleanup: Makefile and gup_test.c
selftests/vm: only some gup_test items are really benchmarks
selftests/vm: gup_test: introduce the dump_pages() sub-test
selftests/vm: run_vmtest.sh: update and clean up gup_test invocation
selftests/vm: hmm-tests: remove the libhugetlbfs dependency
Documentation/core-api/pin_user_pages.rst | 6 +-
arch/s390/configs/debug_defconfig | 2 +-
arch/s390/configs/defconfig | 2 +-
mm/Kconfig | 21 +-
mm/Makefile | 2 +-
mm/{gup_benchmark.c => gup_test.c} | 109 ++++++----
mm/gup_test.h | 32 +++
tools/testing/selftests/vm/.gitignore | 3 +-
tools/testing/selftests/vm/Makefile | 38 +++-
tools/testing/selftests/vm/check_config.sh | 31 +++
tools/testing/selftests/vm/config | 2 +-
tools/testing/selftests/vm/gup_benchmark.c | 137 -------------
tools/testing/selftests/vm/gup_test.c | 188 ++++++++++++++++++
tools/testing/selftests/vm/hmm-tests.c | 10 +-
.../vm/{run_vmtests => run_vmtest.sh} | 24 ++-
15 files changed, 404 insertions(+), 203 deletions(-)
rename mm/{gup_benchmark.c => gup_test.c} (59%)
create mode 100644 mm/gup_test.h
create mode 100755 tools/testing/selftests/vm/check_config.sh
delete mode 100644 tools/testing/selftests/vm/gup_benchmark.c
create mode 100644 tools/testing/selftests/vm/gup_test.c
rename tools/testing/selftests/vm/{run_vmtests => run_vmtest.sh} (91%)
--
2.28.0
HMM selftests are incredibly useful, but they are only effective if
people actually build and run them. All the other tests in selftests/vm
can be built with very standard, always-available libraries: libpthread,
librt. The hmm-tests.c program, on the other hand, requires something
that is (much) less readily available: libhugetlbfs. And so the build
will typically fail for many developers.
A simple attempt to install libhugetlbfs will also run into
complications on some common distros these days: Fedora and Arch Linux
(yes, Arch AUR has it, but that's fragile, as always with AUR). The
library is not maintained actively enough at the moment, for distros to
deal with it. I had to build it from source, for Fedora, and that didn't
go too smoothly either.
It turns out that, out of 21 tests in hmm-tests.c, only 2 actually
require functionality from libhugetlbfs. Therefore, if libhugetlbfs is
missing, simply ifdef those two tests out and allow the developer to at
least have the other 19 tests, if they don't want to pause to work
through the above issues. Also issue a warning, so that it's clear that
there is an imperfection in the build.
In order to do that, a tiny shell script (check_config.sh) runs a quick
compile (not link, that's too prone to false failures with library
paths), and basically, if the compiler doesn't find hugetlbfs.h in its
standard locations, then the script concludes that libhugetlbfs is not
available. The output is in two files, one for inclusion in hmm-test.c
(local_config.h), and one for inclusion in the Makefile
(local_config.mk).
Cc: Ralph Campbell <[email protected]>
Signed-off-by: John Hubbard <[email protected]>
---
tools/testing/selftests/vm/.gitignore | 1 +
tools/testing/selftests/vm/Makefile | 24 +++++++++++++++--
tools/testing/selftests/vm/check_config.sh | 31 ++++++++++++++++++++++
tools/testing/selftests/vm/hmm-tests.c | 10 ++++++-
4 files changed, 63 insertions(+), 3 deletions(-)
create mode 100755 tools/testing/selftests/vm/check_config.sh
diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore
index 2c8ddcf41c0e..e90d28bcd518 100644
--- a/tools/testing/selftests/vm/.gitignore
+++ b/tools/testing/selftests/vm/.gitignore
@@ -20,3 +20,4 @@ va_128TBswitch
map_fixed_noreplace
write_to_hugetlbfs
hmm-tests
+local_config.*
diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
index 2579242386ac..019cbb7f3cf8 100644
--- a/tools/testing/selftests/vm/Makefile
+++ b/tools/testing/selftests/vm/Makefile
@@ -1,5 +1,8 @@
# SPDX-License-Identifier: GPL-2.0
# Makefile for vm selftests
+
+include local_config.mk
+
uname_M := $(shell uname -m 2>/dev/null || echo not)
MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/')
@@ -76,8 +79,6 @@ TEST_FILES := test_vmalloc.sh
KSFT_KHDR_INSTALL := 1
include ../lib.mk
-$(OUTPUT)/hmm-tests: LDLIBS += -lhugetlbfs
-
ifeq ($(ARCH),x86_64)
BINARIES_32 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_32))
BINARIES_64 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_64))
@@ -130,3 +131,22 @@ endif
$(OUTPUT)/mlock-random-test: LDLIBS += -lcap
$(OUTPUT)/gup_test: ../../../../mm/gup_test.h
+
+$(OUTPUT)/hmm-tests: local_config.h
+
+# HMM_EXTRA_LIBS may get set in local_config.mk, or it may be left empty.
+$(OUTPUT)/hmm-tests: LDLIBS += $(HMM_EXTRA_LIBS)
+
+local_config.mk local_config.h: check_config.sh
+ ./check_config.sh $(CC)
+
+EXTRA_CLEAN += local_config.mk local_config.h
+
+ifeq ($(HMM_EXTRA_LIBS),)
+all: warn_missing_hugelibs
+
+warn_missing_hugelibs:
+ @echo ; \
+ echo "Warning: missing libhugetlbfs support. Some HMM tests will be skipped." ; \
+ echo
+endif
diff --git a/tools/testing/selftests/vm/check_config.sh b/tools/testing/selftests/vm/check_config.sh
new file mode 100755
index 000000000000..079c8a40b85d
--- /dev/null
+++ b/tools/testing/selftests/vm/check_config.sh
@@ -0,0 +1,31 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Probe for libraries and create header files to record the results. Both C
+# header files and Makefile include fragments are created.
+
+OUTPUT_H_FILE=local_config.h
+OUTPUT_MKFILE=local_config.mk
+
+# libhugetlbfs
+tmpname=$(mktemp)
+tmpfile_c=${tmpname}.c
+tmpfile_o=${tmpname}.o
+
+echo "#include <sys/types.h>" > $tmpfile_c
+echo "#include <hugetlbfs.h>" >> $tmpfile_c
+echo "int func(void) { return 0; }" >> $tmpfile_c
+
+CC=${1:?"Usage: $0 <compiler> # example compiler: gcc"}
+$CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1
+
+if [ -f $tmpfile_o ]; then
+ echo "#define LOCAL_CONFIG_HAVE_LIBHUGETLBFS 1" > $OUTPUT_H_FILE
+ echo "HMM_EXTRA_LIBS = -lhugetlbfs" > $OUTPUT_MKFILE
+else
+ echo "// No libhugetlbfs support found" > $OUTPUT_H_FILE
+ echo "# No libhugetlbfs support found, so:" > $OUTPUT_MKFILE
+ echo "HMM_EXTRA_LIBS = " >> $OUTPUT_MKFILE
+fi
+
+rm ${tmpname}.*
diff --git a/tools/testing/selftests/vm/hmm-tests.c b/tools/testing/selftests/vm/hmm-tests.c
index 0a28a6a29581..6b79723d7dc6 100644
--- a/tools/testing/selftests/vm/hmm-tests.c
+++ b/tools/testing/selftests/vm/hmm-tests.c
@@ -21,12 +21,16 @@
#include <strings.h>
#include <time.h>
#include <pthread.h>
-#include <hugetlbfs.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
+#include "./local_config.h"
+#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
+#include <hugetlbfs.h>
+#endif
+
/*
* This is a private UAPI to the kernel test module so it isn't exported
* in the usual include/uapi/... directory.
@@ -662,6 +666,7 @@ TEST_F(hmm, anon_write_huge)
hmm_buffer_free(buffer);
}
+#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
/*
* Write huge TLBFS page.
*/
@@ -720,6 +725,7 @@ TEST_F(hmm, anon_write_hugetlbfs)
buffer->ptr = NULL;
hmm_buffer_free(buffer);
}
+#endif /* LOCAL_CONFIG_HAVE_LIBHUGETLBFS */
/*
* Read mmap'ed file memory.
@@ -1336,6 +1342,7 @@ TEST_F(hmm2, snapshot)
hmm_buffer_free(buffer);
}
+#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
/*
* Test the hmm_range_fault() HMM_PFN_PMD flag for large pages that
* should be mapped by a large page table entry.
@@ -1411,6 +1418,7 @@ TEST_F(hmm, compound)
buffer->ptr = NULL;
hmm_buffer_free(buffer);
}
+#endif /* LOCAL_CONFIG_HAVE_LIBHUGETLBFS */
/*
* Test two devices reading the same memory (double mapped).
--
2.28.0
On Tue, 29 Sep 2020, John Hubbard wrote:
> HMM selftests are incredibly useful, but they are only effective if
> people actually build and run them. All the other tests in selftests/vm
> can be built with very standard, always-available libraries: libpthread,
> librt. The hmm-tests.c program, on the other hand, requires something
> that is (much) less readily available: libhugetlbfs. And so the build
> will typically fail for many developers.
>
> A simple attempt to install libhugetlbfs will also run into
> complications on some common distros these days: Fedora and Arch Linux
> (yes, Arch AUR has it, but that's fragile, as always with AUR). The
> library is not maintained actively enough at the moment, for distros to
> deal with it. I had to build it from source, for Fedora, and that didn't
> go too smoothly either.
>
> It turns out that, out of 21 tests in hmm-tests.c, only 2 actually
> require functionality from libhugetlbfs. Therefore, if libhugetlbfs is
> missing, simply ifdef those two tests out and allow the developer to at
> least have the other 19 tests, if they don't want to pause to work
> through the above issues. Also issue a warning, so that it's clear that
> there is an imperfection in the build.
>
> In order to do that, a tiny shell script (check_config.sh) runs a quick
> compile (not link, that's too prone to false failures with library
> paths), and basically, if the compiler doesn't find hugetlbfs.h in its
> standard locations, then the script concludes that libhugetlbfs is not
> available. The output is in two files, one for inclusion in hmm-test.c
> (local_config.h), and one for inclusion in the Makefile
> (local_config.mk).
>
> Cc: Ralph Campbell <[email protected]>
> Signed-off-by: John Hubbard <[email protected]>
> ---
> tools/testing/selftests/vm/.gitignore | 1 +
> tools/testing/selftests/vm/Makefile | 24 +++++++++++++++--
> tools/testing/selftests/vm/check_config.sh | 31 ++++++++++++++++++++++
> tools/testing/selftests/vm/hmm-tests.c | 10 ++++++-
> 4 files changed, 63 insertions(+), 3 deletions(-)
> create mode 100755 tools/testing/selftests/vm/check_config.sh
>
> diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore
> index 2c8ddcf41c0e..e90d28bcd518 100644
> --- a/tools/testing/selftests/vm/.gitignore
> +++ b/tools/testing/selftests/vm/.gitignore
> @@ -20,3 +20,4 @@ va_128TBswitch
> map_fixed_noreplace
> write_to_hugetlbfs
> hmm-tests
> +local_config.*
> diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
> index 2579242386ac..019cbb7f3cf8 100644
> --- a/tools/testing/selftests/vm/Makefile
> +++ b/tools/testing/selftests/vm/Makefile
> @@ -1,5 +1,8 @@
> # SPDX-License-Identifier: GPL-2.0
> # Makefile for vm selftests
> +
> +include local_config.mk
> +
John, your change makes:
tools/testing/selftests$ make clean
fail with:
make[1]: Entering directory
'/home/lukas/repositories/kernel.org/pub/scm/linux/kernel/git/next/linux-next/tools/testing/selftests/vm'
Makefile:4: local_config.mk: No such file or directory
./check_config.sh gcc
make[1]: execvp: ./check_config.sh: Permission denied
Makefile:141: recipe for target 'local_config.mk' failed
make[1]: *** [local_config.mk] Error 127
when make clean is called without building the vm selftests before, e.g.,
when someone just cleans everything in the repository to just be sure that
everything is clean.
Lukas
> uname_M := $(shell uname -m 2>/dev/null || echo not)
> MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/')
>
> @@ -76,8 +79,6 @@ TEST_FILES := test_vmalloc.sh
> KSFT_KHDR_INSTALL := 1
> include ../lib.mk
>
> -$(OUTPUT)/hmm-tests: LDLIBS += -lhugetlbfs
> -
> ifeq ($(ARCH),x86_64)
> BINARIES_32 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_32))
> BINARIES_64 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_64))
> @@ -130,3 +131,22 @@ endif
> $(OUTPUT)/mlock-random-test: LDLIBS += -lcap
>
> $(OUTPUT)/gup_test: ../../../../mm/gup_test.h
> +
> +$(OUTPUT)/hmm-tests: local_config.h
> +
> +# HMM_EXTRA_LIBS may get set in local_config.mk, or it may be left empty.
> +$(OUTPUT)/hmm-tests: LDLIBS += $(HMM_EXTRA_LIBS)
> +
> +local_config.mk local_config.h: check_config.sh
> + ./check_config.sh $(CC)
> +
> +EXTRA_CLEAN += local_config.mk local_config.h
> +
> +ifeq ($(HMM_EXTRA_LIBS),)
> +all: warn_missing_hugelibs
> +
> +warn_missing_hugelibs:
> + @echo ; \
> + echo "Warning: missing libhugetlbfs support. Some HMM tests will be skipped." ; \
> + echo
> +endif
> diff --git a/tools/testing/selftests/vm/check_config.sh b/tools/testing/selftests/vm/check_config.sh
> new file mode 100755
> index 000000000000..079c8a40b85d
> --- /dev/null
> +++ b/tools/testing/selftests/vm/check_config.sh
> @@ -0,0 +1,31 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Probe for libraries and create header files to record the results. Both C
> +# header files and Makefile include fragments are created.
> +
> +OUTPUT_H_FILE=local_config.h
> +OUTPUT_MKFILE=local_config.mk
> +
> +# libhugetlbfs
> +tmpname=$(mktemp)
> +tmpfile_c=${tmpname}.c
> +tmpfile_o=${tmpname}.o
> +
> +echo "#include <sys/types.h>" > $tmpfile_c
> +echo "#include <hugetlbfs.h>" >> $tmpfile_c
> +echo "int func(void) { return 0; }" >> $tmpfile_c
> +
> +CC=${1:?"Usage: $0 <compiler> # example compiler: gcc"}
> +$CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1
> +
> +if [ -f $tmpfile_o ]; then
> + echo "#define LOCAL_CONFIG_HAVE_LIBHUGETLBFS 1" > $OUTPUT_H_FILE
> + echo "HMM_EXTRA_LIBS = -lhugetlbfs" > $OUTPUT_MKFILE
> +else
> + echo "// No libhugetlbfs support found" > $OUTPUT_H_FILE
> + echo "# No libhugetlbfs support found, so:" > $OUTPUT_MKFILE
> + echo "HMM_EXTRA_LIBS = " >> $OUTPUT_MKFILE
> +fi
> +
> +rm ${tmpname}.*
> diff --git a/tools/testing/selftests/vm/hmm-tests.c b/tools/testing/selftests/vm/hmm-tests.c
> index 0a28a6a29581..6b79723d7dc6 100644
> --- a/tools/testing/selftests/vm/hmm-tests.c
> +++ b/tools/testing/selftests/vm/hmm-tests.c
> @@ -21,12 +21,16 @@
> #include <strings.h>
> #include <time.h>
> #include <pthread.h>
> -#include <hugetlbfs.h>
> #include <sys/types.h>
> #include <sys/stat.h>
> #include <sys/mman.h>
> #include <sys/ioctl.h>
>
> +#include "./local_config.h"
> +#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
> +#include <hugetlbfs.h>
> +#endif
> +
> /*
> * This is a private UAPI to the kernel test module so it isn't exported
> * in the usual include/uapi/... directory.
> @@ -662,6 +666,7 @@ TEST_F(hmm, anon_write_huge)
> hmm_buffer_free(buffer);
> }
>
> +#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
> /*
> * Write huge TLBFS page.
> */
> @@ -720,6 +725,7 @@ TEST_F(hmm, anon_write_hugetlbfs)
> buffer->ptr = NULL;
> hmm_buffer_free(buffer);
> }
> +#endif /* LOCAL_CONFIG_HAVE_LIBHUGETLBFS */
>
> /*
> * Read mmap'ed file memory.
> @@ -1336,6 +1342,7 @@ TEST_F(hmm2, snapshot)
> hmm_buffer_free(buffer);
> }
>
> +#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
> /*
> * Test the hmm_range_fault() HMM_PFN_PMD flag for large pages that
> * should be mapped by a large page table entry.
> @@ -1411,6 +1418,7 @@ TEST_F(hmm, compound)
> buffer->ptr = NULL;
> hmm_buffer_free(buffer);
> }
> +#endif /* LOCAL_CONFIG_HAVE_LIBHUGETLBFS */
>
> /*
> * Test two devices reading the same memory (double mapped).
> --
> 2.28.0
>
>
On 10/4/20 12:55 AM, Lukas Bulwahn wrote:
> On Tue, 29 Sep 2020, John Hubbard wrote:
...
> John, your change makes:
>
> tools/testing/selftests$ make clean
>
> fail with:
>
> make[1]: Entering directory
> '/home/lukas/repositories/kernel.org/pub/scm/linux/kernel/git/next/linux-next/tools/testing/selftests/vm'
> Makefile:4: local_config.mk: No such file or directory
> ./check_config.sh gcc
> make[1]: execvp: ./check_config.sh: Permission denied
> Makefile:141: recipe for target 'local_config.mk' failed
> make[1]: *** [local_config.mk] Error 127
Yes, there's a fix for that, here:
https://lore.kernel.org/r/[email protected]
...and Andrew Morton has merged it into his tree as of yesterday, too.
(As shown in the attached email, which has notes about how that flow
works.)
Sorry that you had to run into that, but this should fix you up.
thanks,
--
John Hubbard
NVIDIA