git: 3b15beb30b3b - main - Implement malloc_domainset_aligned(9).

[Konstantin Belousov]

The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=3b15beb30b3b4ba17bae3d1d43c8c04ff862bb57

commit 3b15beb30b3b4ba17bae3d1d43c8c04ff862bb57
Author:     Konstantin Belousov <kib at FreeBSD.org>
AuthorDate: 2021-01-14 03:59:34 +0000
Commit:     Konstantin Belousov <kib at FreeBSD.org>
CommitDate: 2021-01-17 17:29:05 +0000

    Implement malloc_domainset_aligned(9).
    
    Change the power-of-two malloc zones to require alignment equal to the
    size [*].  Current uma allocator already provides such alignment, so in
    fact this change does not change anything except providing future-proof
    setup.
    
    Suggested by:   markj [*]
    Reviewed by:    andrew, jah, markj
    Tested by:      pho
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D28147
---
 sys/kern/kern_malloc.c | 28 +++++++++++++++++++++++++++-
 sys/sys/malloc.h       |  3 +++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
index f79352f2fbfd..232472708b9b 100644
--- a/sys/kern/kern_malloc.c
+++ b/sys/kern/kern_malloc.c
@@ -763,6 +763,28 @@ malloc_domainset_exec(size_t size, struct malloc_type *mtp, struct domainset *ds
 	return (malloc_large(&size, mtp, ds, flags DEBUG_REDZONE_ARG));
 }
 
+void *
+malloc_domainset_aligned(size_t size, size_t align,
+    struct malloc_type *mtp, struct domainset *ds, int flags)
+{
+	void *res;
+
+	KASSERT(align != 0 && powerof2(align),
+	    ("malloc_domainset_aligned: wrong align %#zx size %#zx",
+	    align, size));
+	KASSERT(align <= kmemzones[nitems(kmemzones) - 2].kz_size,
+	    ("malloc_domainset_aligned: align %#zx (size %#zx) too large",
+	    align, size));
+
+	if (size < align)
+		size = align;
+	res = malloc_domainset(size, mtp, ds, flags);
+	KASSERT(res == NULL || ((uintptr_t)res & (align - 1)) == 0,
+	    ("malloc_domainset_aligned: result not aligned %p size %#zx "
+	    "align %#zx", res, size, align));
+	return (res);
+}
+
 void *
 mallocarray(size_t nmemb, size_t size, struct malloc_type *type, int flags)
 {
@@ -1146,8 +1168,12 @@ mallocinit(void *dummy)
 	for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) {
 		int size = kmemzones[indx].kz_size;
 		const char *name = kmemzones[indx].kz_name;
+		size_t align;
 		int subzone;
 
+		align = UMA_ALIGN_PTR;
+		if (powerof2(size) && size > sizeof(void *))
+			align = size - 1;
 		for (subzone = 0; subzone < numzones; subzone++) {
 			kmemzones[indx].kz_zone[subzone] =
 			    uma_zcreate(name, size,
@@ -1156,7 +1182,7 @@ mallocinit(void *dummy)
 #else
 			    NULL, NULL, NULL, NULL,
 #endif
-			    UMA_ALIGN_PTR, UMA_ZONE_MALLOC);
+			    align, UMA_ZONE_MALLOC);
 		}
 		for (;i <= size; i+= KMEM_ZBASE)
 			kmemsize[i >> KMEM_ZSHIFT] = indx;
diff --git a/sys/sys/malloc.h b/sys/sys/malloc.h
index bf87e3168e01..a11dd767efc5 100644
--- a/sys/sys/malloc.h
+++ b/sys/sys/malloc.h
@@ -261,6 +261,9 @@ void	*realloc(void *addr, size_t size, struct malloc_type *type, int flags)
 	    __result_use_check __alloc_size(2);
 void	*reallocf(void *addr, size_t size, struct malloc_type *type, int flags)
 	    __result_use_check __alloc_size(2);
+void	*malloc_domainset_aligned(size_t size, size_t align,
+	    struct malloc_type *mtp, struct domainset *ds, int flags)
+	    __malloc_like __result_use_check __alloc_size(1);
 
 struct malloc_type *malloc_desc2type(const char *desc);