| Message ID | 20201202211542.1121189-1-axelrasmussen@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | userfaultfd: selftests: make __{s,u}64 format specifiers portable | expand |
On Wed, Dec 2, 2020 at 3:10 PM Peter Xu <peterx@redhat.com> wrote: > > Hi, Axel, > > Looks mostly good to me, but a few nitpickings below. > > On Wed, Dec 02, 2020 at 01:15:42PM -0800, Axel Rasmussen wrote: > > [...] > > > +static void uffd_error(const char *message, __s64 code) > > +{ > > + fprintf(stderr, "%s: %" PRId64 "\n", message, (int64_t)code); > > + exit(1); > > +} > > IMHO a macro that can take arbitrary parameters would be nicer, but if it > satisfy our need, definitely ok too. > > [...] > > > @@ -340,7 +348,8 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp) > > prms.mode = wp ? UFFDIO_WRITEPROTECT_MODE_WP : 0; > > > > if (ioctl(ufd, UFFDIO_WRITEPROTECT, &prms)) { > > - fprintf(stderr, "clear WP failed for address 0x%Lx\n", start); > > + fprintf(stderr, "clear WP failed for address 0x%" PRIx64 "\n", > > + (uint64_t)start); > > exit(1); > > Is it intended to not use uffd_error() here? Yes, this is intentional. This particular case prints the value in hexadecimal, rather than decimal. (Agree that uffd_error() could be made more general to cover cases like this. I opted for the simplest thing which covers all but two cases - this one, and one where we "return 1;" instead of "exit(1);" - but I don't feel strongly.) > > > } > > } > > [...] > > > @@ -979,26 +981,20 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) > > if (ret) { > > /* real retval in ufdio_zeropage.zeropage */ > > if (has_zeropage) { > > - if (uffdio_zeropage.zeropage == -EEXIST) { > > - fprintf(stderr, "UFFDIO_ZEROPAGE -EEXIST\n"); > > - exit(1); > > - } else { > > - fprintf(stderr, "UFFDIO_ZEROPAGE error %Ld\n", > > - uffdio_zeropage.zeropage); > > - exit(1); > > - } > > + uffd_error(uffdio_zeropage.zeropage == -EEXIST ? > > + "UFFDIO_ZEROPAGE -EEXIST" : > > + "UFFDIO_ZEROPAGE error", > > Nit: The indents here are a bit odd.. This is what clang-format yields. Are you thinking it would be better to line everything up with the ( in uffd_error( ? Or, perhaps this case is a good reason to make uffd_error() a variadic macro so we can insert "-EEXIST" || "error" with a "%s". > > Thanks, > > -- > Peter Xu >
On Thu, Dec 3, 2020 at 12:55 AM Axel Rasmussen <axelrasmussen@google.com> wrote: > > This is what clang-format yields. Are you thinking it would be better > to line everything up with the ( in uffd_error( ? Yeah, sometimes clang-format cannot do a good job with the 80 column limit + 8 tabs. You are definitely not forced to follow clang-format output by any means. Subsystem maintainers decide what style they prefer anyway, which could range from a manual approach to following clang-format strictly. Clang-format implements the general kernel style as closely as we could get it so far (it will improve more in the future when we raise the minimum clang-format version required). See Doc/process/clang-format.rst. > Or, perhaps this case is a good reason to make uffd_error() a variadic > macro so we can insert "-EEXIST" || "error" with a "%s". ...and indeed, sometimes it is a hint that simplifying things could help :-) Cheers, Miguel
On Wed, Dec 02, 2020 at 03:52:56PM -0800, Axel Rasmussen wrote: > On Wed, Dec 2, 2020 at 3:10 PM Peter Xu <peterx@redhat.com> wrote: > > > > Hi, Axel, > > > > Looks mostly good to me, but a few nitpickings below. > > > > On Wed, Dec 02, 2020 at 01:15:42PM -0800, Axel Rasmussen wrote: > > > > [...] > > > > > +static void uffd_error(const char *message, __s64 code) > > > +{ > > > + fprintf(stderr, "%s: %" PRId64 "\n", message, (int64_t)code); > > > + exit(1); > > > +} > > > > IMHO a macro that can take arbitrary parameters would be nicer, but if it > > satisfy our need, definitely ok too. > > > > [...] > > > > > @@ -340,7 +348,8 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp) > > > prms.mode = wp ? UFFDIO_WRITEPROTECT_MODE_WP : 0; > > > > > > if (ioctl(ufd, UFFDIO_WRITEPROTECT, &prms)) { > > > - fprintf(stderr, "clear WP failed for address 0x%Lx\n", start); > > > + fprintf(stderr, "clear WP failed for address 0x%" PRIx64 "\n", > > > + (uint64_t)start); > > > exit(1); > > > > Is it intended to not use uffd_error() here? > > Yes, this is intentional. This particular case prints the value in > hexadecimal, rather than decimal. > > (Agree that uffd_error() could be made more general to cover cases > like this. I opted for the simplest thing which covers all but two > cases - this one, and one where we "return 1;" instead of "exit(1);" - > but I don't feel strongly.) Actually it's as simple as: #define uffd_error(...) do { \ fprintf(stderr, __VA_ARGS__); \ fprintf(stderr, "\n"); \ exit(1); \ } while (0) But it's okay, I think. > > > > > > } > > > } > > > > [...] > > > > > @@ -979,26 +981,20 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) > > > if (ret) { > > > /* real retval in ufdio_zeropage.zeropage */ > > > if (has_zeropage) { > > > - if (uffdio_zeropage.zeropage == -EEXIST) { > > > - fprintf(stderr, "UFFDIO_ZEROPAGE -EEXIST\n"); > > > - exit(1); > > > - } else { > > > - fprintf(stderr, "UFFDIO_ZEROPAGE error %Ld\n", > > > - uffdio_zeropage.zeropage); > > > - exit(1); > > > - } > > > + uffd_error(uffdio_zeropage.zeropage == -EEXIST ? > > > + "UFFDIO_ZEROPAGE -EEXIST" : > > > + "UFFDIO_ZEROPAGE error", > > > > Nit: The indents here are a bit odd.. > > This is what clang-format yields. Are you thinking it would be better > to line everything up with the ( in uffd_error( ? > > Or, perhaps this case is a good reason to make uffd_error() a variadic > macro so we can insert "-EEXIST" || "error" with a "%s". Yes. It fixes a build warning, so I think current patch is fine too. No matter whether you'd like a v2, please feel free to take: Acked-by: Peter Xu <peterx@redhat.com> Thanks, -- Peter Xu
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 9b0912a01777..31e1ff887e4b 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -55,6 +55,8 @@ #include <setjmp.h> #include <stdbool.h> #include <assert.h> +#include <inttypes.h> +#include <stdint.h> #include "../kselftest.h" @@ -135,6 +137,12 @@ static void usage(void) exit(1); } +static void uffd_error(const char *message, __s64 code) +{ + fprintf(stderr, "%s: %" PRId64 "\n", message, (int64_t)code); + exit(1); +} + static void uffd_stats_reset(struct uffd_stats *uffd_stats, unsigned long n_cpus) { @@ -331,7 +339,7 @@ static int my_bcmp(char *str1, char *str2, size_t n) static void wp_range(int ufd, __u64 start, __u64 len, bool wp) { - struct uffdio_writeprotect prms = { 0 }; + struct uffdio_writeprotect prms; /* Write protection page faults */ prms.range.start = start; @@ -340,7 +348,8 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp) prms.mode = wp ? UFFDIO_WRITEPROTECT_MODE_WP : 0; if (ioctl(ufd, UFFDIO_WRITEPROTECT, &prms)) { - fprintf(stderr, "clear WP failed for address 0x%Lx\n", start); + fprintf(stderr, "clear WP failed for address 0x%" PRIx64 "\n", + (uint64_t)start); exit(1); } } @@ -474,14 +483,11 @@ static void retry_copy_page(int ufd, struct uffdio_copy *uffdio_copy, if (ioctl(ufd, UFFDIO_COPY, uffdio_copy)) { /* real retval in ufdio_copy.copy */ if (uffdio_copy->copy != -EEXIST) { - fprintf(stderr, "UFFDIO_COPY retry error %Ld\n", - uffdio_copy->copy); - exit(1); + uffd_error("UFFDIO_COPY retry error", + uffdio_copy->copy); } - } else { - fprintf(stderr, "UFFDIO_COPY retry unexpected %Ld\n", - uffdio_copy->copy); exit(1); - } + } else + uffd_error("UFFDIO_COPY retry unexpected", uffdio_copy->copy); } static int __copy_page(int ufd, unsigned long offset, bool retry) @@ -502,15 +508,11 @@ static int __copy_page(int ufd, unsigned long offset, bool retry) uffdio_copy.copy = 0; if (ioctl(ufd, UFFDIO_COPY, &uffdio_copy)) { /* real retval in ufdio_copy.copy */ - if (uffdio_copy.copy != -EEXIST) { - fprintf(stderr, "UFFDIO_COPY error %Ld\n", - uffdio_copy.copy); - exit(1); - } - } else if (uffdio_copy.copy != page_size) { - fprintf(stderr, "UFFDIO_COPY unexpected copy %Ld\n", - uffdio_copy.copy); exit(1); - } else { + if (uffdio_copy.copy != -EEXIST) + uffd_error("UFFDIO_COPY error", uffdio_copy.copy); + } else if (uffdio_copy.copy != page_size) + uffd_error("UFFDIO_COPY unexpected copy", uffdio_copy.copy); + else { if (test_uffdio_copy_eexist && retry) { test_uffdio_copy_eexist = false; retry_copy_page(ufd, &uffdio_copy, offset); @@ -788,7 +790,8 @@ static int userfaultfd_open(int features) return 1; } if (uffdio_api.api != UFFD_API) { - fprintf(stderr, "UFFDIO_API error %Lu\n", uffdio_api.api); + fprintf(stderr, "UFFDIO_API error: %" PRIu64 "\n", + (uint64_t)uffdio_api.api); return 1; } @@ -950,13 +953,12 @@ static void retry_uffdio_zeropage(int ufd, offset); if (ioctl(ufd, UFFDIO_ZEROPAGE, uffdio_zeropage)) { if (uffdio_zeropage->zeropage != -EEXIST) { - fprintf(stderr, "UFFDIO_ZEROPAGE retry error %Ld\n", - uffdio_zeropage->zeropage); - exit(1); + uffd_error("UFFDIO_ZEROPAGE retry error", + uffdio_zeropage->zeropage); } } else { - fprintf(stderr, "UFFDIO_ZEROPAGE retry unexpected %Ld\n", - uffdio_zeropage->zeropage); exit(1); + uffd_error("UFFDIO_ZEROPAGE retry unexpected", + uffdio_zeropage->zeropage); } } @@ -979,26 +981,20 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) if (ret) { /* real retval in ufdio_zeropage.zeropage */ if (has_zeropage) { - if (uffdio_zeropage.zeropage == -EEXIST) { - fprintf(stderr, "UFFDIO_ZEROPAGE -EEXIST\n"); - exit(1); - } else { - fprintf(stderr, "UFFDIO_ZEROPAGE error %Ld\n", - uffdio_zeropage.zeropage); - exit(1); - } + uffd_error(uffdio_zeropage.zeropage == -EEXIST ? + "UFFDIO_ZEROPAGE -EEXIST" : + "UFFDIO_ZEROPAGE error", + uffdio_zeropage.zeropage); } else { if (uffdio_zeropage.zeropage != -EINVAL) { - fprintf(stderr, - "UFFDIO_ZEROPAGE not -EINVAL %Ld\n", - uffdio_zeropage.zeropage); - exit(1); + uffd_error("UFFDIO_ZEROPAGE not -EINVAL", + uffdio_zeropage.zeropage); } } } else if (has_zeropage) { if (uffdio_zeropage.zeropage != page_size) { - fprintf(stderr, "UFFDIO_ZEROPAGE unexpected %Ld\n", - uffdio_zeropage.zeropage); exit(1); + uffd_error("UFFDIO_ZEROPAGE unexpected", + uffdio_zeropage.zeropage); } else { if (test_uffdio_zeropage_eexist && retry) { test_uffdio_zeropage_eexist = false; @@ -1008,9 +1004,8 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) return 1; } } else { - fprintf(stderr, - "UFFDIO_ZEROPAGE succeeded %Ld\n", - uffdio_zeropage.zeropage); exit(1); + uffd_error("UFFDIO_ZEROPAGE succeeded", + uffdio_zeropage.zeropage); } return 0;
On certain platforms (powerpcle is the one on which I ran into this), "%Ld" and "%Lu" are unsuitable for printing __s64 and __u64, respectively, resulting in a build warning. Cast to {u,}int64_t, and use the PRI{d,u}64 macros defined in inttypes.h to print them. This ought to be portable to all platforms. Splitting this off into a separate function lets us remove some lines, and get rid of some (I would argue) stylistically odd cases where we joined printf() and exit() into a single statement with a ,. Finally, this also fixes a "missing braces around initializer" warning when we initialize prms in wp_range(). Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> --- tools/testing/selftests/vm/userfaultfd.c | 77 +++++++++++------------- 1 file changed, 36 insertions(+), 41 deletions(-)