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| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2021-08-13 08:36:29 -0300 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2021-12-15 17:35:14 -0300 |
| commit | 5f6d8d97c69748180f0031dfa385aff75062c4d5 (patch) | |
| tree | 97837a8eab4175385c32bacb10dc633b9070f266 /malloc/arena.c | |
| parent | cb976fba4c51ede7bf8cee5035888527c308dfbc (diff) | |
| download | glibc-5f6d8d97c69748180f0031dfa385aff75062c4d5.tar.gz glibc-5f6d8d97c69748180f0031dfa385aff75062c4d5.tar.xz glibc-5f6d8d97c69748180f0031dfa385aff75062c4d5.zip | |
malloc: Add madvise support for Transparent Huge Pages
Linux Transparent Huge Pages (THP) current supports three different states: 'never', 'madvise', and 'always'. The 'never' is self-explanatory and 'always' will enable THP for all anonymous pages. However, 'madvise' is still the default for some system and for such case THP will be only used if the memory range is explicity advertise by the program through a madvise(MADV_HUGEPAGE) call. To enable it a new tunable is provided, 'glibc.malloc.hugetlb', where setting to a value diffent than 0 enables the madvise call. This patch issues the madvise(MADV_HUGEPAGE) call after a successful mmap() call at sysmalloc() with sizes larger than the default huge page size. The madvise() call is disable is system does not support THP or if it has the mode set to "never" and on Linux only support one page size for THP, even if the architecture supports multiple sizes. To test is a new rule is added tests-malloc-hugetlb1, which run the addes tests with the required GLIBC_TUNABLE setting. Checked on x86_64-linux-gnu. Reviewed-by: DJ Delorie <dj@redhat.com>
Diffstat (limited to 'malloc/arena.c')
| -rw-r--r-- | malloc/arena.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/malloc/arena.c b/malloc/arena.c index 78ef4cf18c..cd00c7bef4 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -230,6 +230,7 @@ TUNABLE_CALLBACK_FNDECL (set_tcache_count, size_t) TUNABLE_CALLBACK_FNDECL (set_tcache_unsorted_limit, size_t) #endif TUNABLE_CALLBACK_FNDECL (set_mxfast, size_t) +TUNABLE_CALLBACK_FNDECL (set_hugetlb, int32_t) #else /* Initialization routine. */ #include <string.h> @@ -330,6 +331,7 @@ ptmalloc_init (void) TUNABLE_CALLBACK (set_tcache_unsorted_limit)); # endif TUNABLE_GET (mxfast, size_t, TUNABLE_CALLBACK (set_mxfast)); + TUNABLE_GET (hugetlb, int32_t, TUNABLE_CALLBACK (set_hugetlb)); #else if (__glibc_likely (_environ != NULL)) { @@ -508,6 +510,9 @@ new_heap (size_t size, size_t top_pad) __munmap (p2, HEAP_MAX_SIZE); return 0; } + + madvise_thp (p2, size); + h = (heap_info *) p2; h->size = size; h->mprotect_size = size; |