diff mbox series

[RFC,v3,02/16] mm: Define __pte_leaf_size() to also take a PMD entry

Message ID cab4f087fa6f5933be4f5673d015da6887546ebd.1716714720.git.christophe.leroy@csgroup.eu (mailing list archive)
State New
Headers show
Series Reimplement huge pages without hugepd on powerpc (8xx, e500, book3s/64) | expand

Commit Message

Christophe Leroy May 26, 2024, 9:22 a.m. UTC
On powerpc 8xx, when a page is 8M size, the information is in the PMD
entry. So allow architectures to provide __pte_leaf_size() instead of
pte_leaf_size() and provide the PMD entry to that function.

When __pte_leaf_size() is not defined, define it as a pte_leaf_size()
so that architectures not interested in the PMD arguments are not
impacted.

Only define a default pte_leaf_size() when __pte_leaf_size() is not
defined to make sure nobody adds new calls to pte_leaf_size() in the
core.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v3: Don't change pte_leaf_size() to not impact other architectures
---
 include/linux/pgtable.h | 3 +++
 kernel/events/core.c    | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

Comments

Oscar Salvador May 27, 2024, 4:52 a.m. UTC | #1
On Sun, May 26, 2024 at 11:22:22AM +0200, Christophe Leroy wrote:
> On powerpc 8xx, when a page is 8M size, the information is in the PMD
> entry. So allow architectures to provide __pte_leaf_size() instead of
> pte_leaf_size() and provide the PMD entry to that function.
> 
> When __pte_leaf_size() is not defined, define it as a pte_leaf_size()
> so that architectures not interested in the PMD arguments are not
> impacted.
> 
> Only define a default pte_leaf_size() when __pte_leaf_size() is not
> defined to make sure nobody adds new calls to pte_leaf_size() in the
> core.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>

thanks, this looks much cleaner.

Reviewed-by: Oscar Salvador <osalvador@suse.de>
diff mbox series

Patch

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 85fc7554cd52..514e05730df1 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1801,9 +1801,12 @@  typedef unsigned int pgtbl_mod_mask;
 #ifndef pmd_leaf_size
 #define pmd_leaf_size(x) PMD_SIZE
 #endif
+#ifndef __pte_leaf_size
 #ifndef pte_leaf_size
 #define pte_leaf_size(x) PAGE_SIZE
 #endif
+#define __pte_leaf_size(x,y) pte_leaf_size(y)
+#endif
 
 /*
  * Some architectures have MMUs that are configurable or selectable at boot
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 724e6d7e128f..d37512f2ebf2 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7585,7 +7585,7 @@  static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr)
 
 	pte = ptep_get_lockless(ptep);
 	if (pte_present(pte))
-		size = pte_leaf_size(pte);
+		size = __pte_leaf_size(pmd, pte);
 	pte_unmap(ptep);
 #endif /* CONFIG_HAVE_FAST_GUP */