| Message ID | 20200603200645.478668-1-rzinsly@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] string: Add page tests for test-strncasecmp and test-strncpy | expand |
On Wed, Jun 03, 2020 at 05:06:45PM -0300, Raphael Moreira Zinsly wrote: > Adds tests to check if strings placed at page bondaries are nit: Add tests nit: boundaries > handled correctly by strncasecmp and strncpy similar to tests > for strncmp and strnlen. This should catch regressions in the > optmized functions. nit: optimized ...but, you can delete this sentence. > --- > string/test-strncasecmp.c | 37 +++++++++++++++++++++++++++++++++++++ > string/test-strncpy.c | 35 +++++++++++++++++++++++++++++++++++ > 2 files changed, 72 insertions(+) > > diff --git a/string/test-strncasecmp.c b/string/test-strncasecmp.c > index 6a9c27beae..bf9838dacb 100644 > --- a/string/test-strncasecmp.c > +++ b/string/test-strncasecmp.c > @@ -137,6 +137,42 @@ do_test (size_t align1, size_t align2, size_t n, size_t len, int max_char, > do_one_test (impl, s1, s2, n, exp_result); > } > > +static void > +do_page_tests (void) > +{ > + size_t i, offset, cacheline_size; > + char *s1, *s2; > + int exp_result; > + > + offset = page_size - 1; > + s1 = (char *) buf1; > + memset (s1, '\1', offset); > + s1[offset] = '\0'; > + > + /* s2 has a fixed offset, almost one page long. > + page_size is actually 2 * getpagesize. */ > + offset = (page_size / 2) - 10; > + s2 = strdup (s1) + offset; s2 is fixed at 10 bytes short of a page boundary... > + /* Start offset for s1. */ > + offset = 3 * page_size / 4; > + s1 += offset; s1 starts from midway through the 2nd page... I misspoke in my earlier review. To start midway through the first page (of the two pages), it should be page_size / 4. I was originally thinking 3/4 into the first actual page, which would actually be 3 * page_size / 8. That "page_size" is actually two pages is quite confusing. > + > + /* Try to cross the page boundary at every offset of a cache line. */ > + cacheline_size = sysconf (_SC_LEVEL1_DCACHE_LINESIZE); > + for (i = 0; i < cacheline_size; ++i) > + { > + exp_result = *s1; > + > + FOR_EACH_IMPL (impl, 0) > + { > + check_result (impl, s1, s2, page_size, -exp_result); > + check_result (impl, s2, s1, page_size, exp_result); > + } > + > + s1++; s1 moves a byte at a time for the length of a cacheline. It seems that s2 will always cross the boundary at the same offset (10), and s1 will never cross a page boundary, so you should adjust s1 above to be somewhere in the middle of the first page. > + } > +} > + > static void > do_random_tests (void) > { > @@ -334,6 +370,7 @@ test_locale (const char *locale) > } > > do_random_tests (); > + do_page_tests (); > } > > int > diff --git a/string/test-strncpy.c b/string/test-strncpy.c > index c978753ad8..fb3332cbac 100644 > --- a/string/test-strncpy.c > +++ b/string/test-strncpy.c > @@ -155,6 +155,40 @@ do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char) > do_one_test (impl, s2, s1, len, n); > } > > +static void > +do_page_tests (void) > +{ > + size_t i, small_len, big_len, short_offset, long_offset; > + CHAR *s1, *s2; > + /* Calculate the null character offset. */ > + size_t last_offset = (page_size / sizeof (CHAR)) - 1; > + > + s2 = (CHAR *) buf1; > + s1 = (CHAR *) buf2; > + MEMSET (s1, '\1', last_offset); > + s1[last_offset] = '\0'; > + > + long_offset = (last_offset + 1) / 2; > + short_offset = last_offset; > + for (i = 0; i < 128; i++) Consider a comment before this line like what you added for test-strncasecmp, above: /* Try to cross the page boundary at every offset of a cache line. */ ...which then prompts the question as to whether you should query and use the cache line size as you did there. Probably yes. > + { > + /* Place long strings ending at page boundary. */ > + long_offset++; > + big_len = last_offset - long_offset; > + /* Place short strings ending at page boundary. */ > + short_offset--; > + small_len = last_offset - short_offset; > + > + FOR_EACH_IMPL (impl, 0) > + { > + do_one_test (impl, s2, (CHAR *) (s1 + short_offset), small_len, > + small_len); > + do_one_test (impl, s2, (CHAR *) (s1 + long_offset), page_size, > + big_len); > + } > + } > +} > + > static void > do_random_tests (void) > { > @@ -317,6 +351,7 @@ test_main (void) > } > > do_random_tests (); > + do_page_tests (); > return ret; > } PC
diff --git a/string/test-strncasecmp.c b/string/test-strncasecmp.c index 6a9c27beae..bf9838dacb 100644 --- a/string/test-strncasecmp.c +++ b/string/test-strncasecmp.c @@ -137,6 +137,42 @@ do_test (size_t align1, size_t align2, size_t n, size_t len, int max_char, do_one_test (impl, s1, s2, n, exp_result); } +static void +do_page_tests (void) +{ + size_t i, offset, cacheline_size; + char *s1, *s2; + int exp_result; + + offset = page_size - 1; + s1 = (char *) buf1; + memset (s1, '\1', offset); + s1[offset] = '\0'; + + /* s2 has a fixed offset, almost one page long. + page_size is actually 2 * getpagesize. */ + offset = (page_size / 2) - 10; + s2 = strdup (s1) + offset; + /* Start offset for s1. */ + offset = 3 * page_size / 4; + s1 += offset; + + /* Try to cross the page boundary at every offset of a cache line. */ + cacheline_size = sysconf (_SC_LEVEL1_DCACHE_LINESIZE); + for (i = 0; i < cacheline_size; ++i) + { + exp_result = *s1; + + FOR_EACH_IMPL (impl, 0) + { + check_result (impl, s1, s2, page_size, -exp_result); + check_result (impl, s2, s1, page_size, exp_result); + } + + s1++; + } +} + static void do_random_tests (void) { @@ -334,6 +370,7 @@ test_locale (const char *locale) } do_random_tests (); + do_page_tests (); } int diff --git a/string/test-strncpy.c b/string/test-strncpy.c index c978753ad8..fb3332cbac 100644 --- a/string/test-strncpy.c +++ b/string/test-strncpy.c @@ -155,6 +155,40 @@ do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char) do_one_test (impl, s2, s1, len, n); } +static void +do_page_tests (void) +{ + size_t i, small_len, big_len, short_offset, long_offset; + CHAR *s1, *s2; + /* Calculate the null character offset. */ + size_t last_offset = (page_size / sizeof (CHAR)) - 1; + + s2 = (CHAR *) buf1; + s1 = (CHAR *) buf2; + MEMSET (s1, '\1', last_offset); + s1[last_offset] = '\0'; + + long_offset = (last_offset + 1) / 2; + short_offset = last_offset; + for (i = 0; i < 128; i++) + { + /* Place long strings ending at page boundary. */ + long_offset++; + big_len = last_offset - long_offset; + /* Place short strings ending at page boundary. */ + short_offset--; + small_len = last_offset - short_offset; + + FOR_EACH_IMPL (impl, 0) + { + do_one_test (impl, s2, (CHAR *) (s1 + short_offset), small_len, + small_len); + do_one_test (impl, s2, (CHAR *) (s1 + long_offset), page_size, + big_len); + } + } +} + static void do_random_tests (void) { @@ -317,6 +351,7 @@ test_main (void) } do_random_tests (); + do_page_tests (); return ret; }