From: "Philippe Mathieu-Daudé" <philmd@linaro.org>
To: qemu-devel@nongnu.org
Cc: "Peter Maydell" <peter.maydell@linaro.org>,
"Jagannathan Raman" <jag.raman@oracle.com>,
qemu-ppc@nongnu.org, "Ilya Leoshkevich" <iii@linux.ibm.com>,
"Thomas Huth" <thuth@redhat.com>,
"Jason Herne" <jjherne@linux.ibm.com>,
"Peter Xu" <peterx@redhat.com>,
"Cédric Le Goater" <clg@redhat.com>,
kvm@vger.kernel.org,
"Christian Borntraeger" <borntraeger@linux.ibm.com>,
"Halil Pasic" <pasic@linux.ibm.com>,
"Matthew Rosato" <mjrosato@linux.ibm.com>,
"Philippe Mathieu-Daudé" <philmd@linaro.org>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Michael S. Tsirkin" <mst@redhat.com>,
"Elena Ufimtseva" <elena.ufimtseva@oracle.com>,
"Richard Henderson" <richard.henderson@linaro.org>,
"Harsh Prateek Bora" <harshpb@linux.ibm.com>,
"Fabiano Rosas" <farosas@suse.de>,
"Eric Farman" <farman@linux.ibm.com>,
qemu-arm@nongnu.org, qemu-s390x@nongnu.org,
"David Hildenbrand" <david@redhat.com>,
"Alex Williamson" <alex.williamson@redhat.com>,
"Nicholas Piggin" <npiggin@gmail.com>
Subject: [PATCH v2 16/18] system/physmem: Reduce cpu_physical_memory_sync_dirty_bitmap() scope
Date: Wed, 1 Oct 2025 19:54:45 +0200 [thread overview]
Message-ID: <20251001175448.18933-17-philmd@linaro.org> (raw)
In-Reply-To: <20251001175448.18933-1-philmd@linaro.org>
cpu_physical_memory_sync_dirty_bitmap() is now only called within
system/physmem.c, by ramblock_sync_dirty_bitmap(). Reduce its scope
by making it internal to this file. Since it doesn't involve any CPU,
remove the 'cpu_' prefix.
Remove the now unneeded "qemu/rcu.h" and "system/memory.h" headers.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
include/system/ram_addr.h | 79 ---------------------------------------
migration/ram.c | 77 +++++++++++++++++++++++++++++++++++++-
2 files changed, 76 insertions(+), 80 deletions(-)
diff --git a/include/system/ram_addr.h b/include/system/ram_addr.h
index cafd258580e..d2d088bbea6 100644
--- a/include/system/ram_addr.h
+++ b/include/system/ram_addr.h
@@ -21,10 +21,7 @@
#include "exec/ramlist.h"
#include "system/ramblock.h"
-#include "system/memory.h"
#include "exec/target_page.h"
-#include "qemu/rcu.h"
-
#include "exec/hwaddr.h"
extern uint64_t total_dirty_pages;
@@ -175,80 +172,4 @@ bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
ram_addr_t start,
ram_addr_t length);
-/* Called with RCU critical section */
-static inline
-uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
- ram_addr_t start,
- ram_addr_t length)
-{
- ram_addr_t addr;
- unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
- uint64_t num_dirty = 0;
- unsigned long *dest = rb->bmap;
-
- /* start address and length is aligned at the start of a word? */
- if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
- (start + rb->offset) &&
- !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
- int k;
- int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
- unsigned long * const *src;
- unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
- unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
- DIRTY_MEMORY_BLOCK_SIZE);
- unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
-
- src = qatomic_rcu_read(
- &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
-
- for (k = page; k < page + nr; k++) {
- if (src[idx][offset]) {
- unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
- unsigned long new_dirty;
- new_dirty = ~dest[k];
- dest[k] |= bits;
- new_dirty &= bits;
- num_dirty += ctpopl(new_dirty);
- }
-
- if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
- offset = 0;
- idx++;
- }
- }
- if (num_dirty) {
- cpu_physical_memory_dirty_bits_cleared(start, length);
- }
-
- if (rb->clear_bmap) {
- /*
- * Postpone the dirty bitmap clear to the point before we
- * really send the pages, also we will split the clear
- * dirty procedure into smaller chunks.
- */
- clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
- length >> TARGET_PAGE_BITS);
- } else {
- /* Slow path - still do that in a huge chunk */
- memory_region_clear_dirty_bitmap(rb->mr, start, length);
- }
- } else {
- ram_addr_t offset = rb->offset;
-
- for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
- if (cpu_physical_memory_test_and_clear_dirty(
- start + addr + offset,
- TARGET_PAGE_SIZE,
- DIRTY_MEMORY_MIGRATION)) {
- long k = (start + addr) >> TARGET_PAGE_BITS;
- if (!test_and_set_bit(k, dest)) {
- num_dirty++;
- }
- }
- }
- }
-
- return num_dirty;
-}
-
#endif
diff --git a/migration/ram.c b/migration/ram.c
index 91e65be83d8..52bdfec91d9 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -935,11 +935,86 @@ bool ramblock_page_is_discarded(RAMBlock *rb, ram_addr_t start)
return false;
}
+/* Called with RCU critical section */
+static uint64_t physical_memory_sync_dirty_bitmap(RAMBlock *rb,
+ ram_addr_t start,
+ ram_addr_t length)
+{
+ ram_addr_t addr;
+ unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
+ uint64_t num_dirty = 0;
+ unsigned long *dest = rb->bmap;
+
+ /* start address and length is aligned at the start of a word? */
+ if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
+ (start + rb->offset) &&
+ !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
+ int k;
+ int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
+ unsigned long * const *src;
+ unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
+ unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
+ DIRTY_MEMORY_BLOCK_SIZE);
+ unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
+
+ src = qatomic_rcu_read(
+ &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
+
+ for (k = page; k < page + nr; k++) {
+ if (src[idx][offset]) {
+ unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
+ unsigned long new_dirty;
+ new_dirty = ~dest[k];
+ dest[k] |= bits;
+ new_dirty &= bits;
+ num_dirty += ctpopl(new_dirty);
+ }
+
+ if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
+ offset = 0;
+ idx++;
+ }
+ }
+ if (num_dirty) {
+ cpu_physical_memory_dirty_bits_cleared(start, length);
+ }
+
+ if (rb->clear_bmap) {
+ /*
+ * Postpone the dirty bitmap clear to the point before we
+ * really send the pages, also we will split the clear
+ * dirty procedure into smaller chunks.
+ */
+ clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
+ length >> TARGET_PAGE_BITS);
+ } else {
+ /* Slow path - still do that in a huge chunk */
+ memory_region_clear_dirty_bitmap(rb->mr, start, length);
+ }
+ } else {
+ ram_addr_t offset = rb->offset;
+
+ for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
+ if (cpu_physical_memory_test_and_clear_dirty(
+ start + addr + offset,
+ TARGET_PAGE_SIZE,
+ DIRTY_MEMORY_MIGRATION)) {
+ long k = (start + addr) >> TARGET_PAGE_BITS;
+ if (!test_and_set_bit(k, dest)) {
+ num_dirty++;
+ }
+ }
+ }
+ }
+
+ return num_dirty;
+}
+
/* Called with RCU critical section */
static void ramblock_sync_dirty_bitmap(RAMState *rs, RAMBlock *rb)
{
uint64_t new_dirty_pages =
- cpu_physical_memory_sync_dirty_bitmap(rb, 0, rb->used_length);
+ physical_memory_sync_dirty_bitmap(rb, 0, rb->used_length);
rs->migration_dirty_pages += new_dirty_pages;
rs->num_dirty_pages_period += new_dirty_pages;
--
2.51.0
next prev parent reply other threads:[~2025-10-01 17:59 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-01 17:54 [PATCH v2 00/18] system/physmem: Extract API out of 'system/ram_addr.h' header Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 01/18] system/ram_addr: Remove unnecessary 'exec/cpu-common.h' header Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 02/18] accel/kvm: Include missing 'exec/target_page.h' header Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 03/18] hw/s390x/s390-stattrib: " Philippe Mathieu-Daudé
2025-10-02 14:18 ` Eric Farman
2025-10-01 17:54 ` [PATCH v2 04/18] hw/vfio/listener: " Philippe Mathieu-Daudé
2025-10-02 8:31 ` Cédric Le Goater
2025-10-01 17:54 ` [PATCH v2 05/18] target/arm/tcg/mte: " Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 06/18] hw: Remove unnecessary 'system/ram_addr.h' header Philippe Mathieu-Daudé
2025-10-01 19:32 ` Jag Raman
2025-10-02 8:37 ` Cédric Le Goater
2025-10-02 15:59 ` Harsh Prateek Bora
2025-10-02 17:38 ` Philippe Mathieu-Daudé
2025-10-02 16:45 ` Eric Farman
2025-10-01 17:54 ` [PATCH v2 07/18] system/physmem: Un-inline cpu_physical_memory_get_dirty_flag() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 08/18] system/physmem: Un-inline cpu_physical_memory_is_clean() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 09/18] system/physmem: Un-inline cpu_physical_memory_range_includes_clean() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 10/18] system/physmem: Un-inline cpu_physical_memory_set_dirty_flag() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 11/18] system/physmem: Un-inline cpu_physical_memory_set_dirty_range() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 12/18] system/physmem: Remove _WIN32 #ifdef'ry Philippe Mathieu-Daudé
2025-10-01 21:00 ` Richard Henderson
2025-10-01 17:54 ` [PATCH v2 13/18] system/physmem: Un-inline cpu_physical_memory_set_dirty_lebitmap() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 14/18] system/physmem: Un-inline cpu_physical_memory_dirty_bits_cleared() Philippe Mathieu-Daudé
2025-10-01 17:54 ` [PATCH v2 15/18] system/physmem: Reduce cpu_physical_memory_clear_dirty_range() scope Philippe Mathieu-Daudé
2025-10-01 17:54 ` Philippe Mathieu-Daudé [this message]
2025-10-01 17:54 ` [PATCH v2 17/18] system/physmem: Drop 'cpu_' prefix in Physical Memory API Philippe Mathieu-Daudé
2025-10-02 8:39 ` Cédric Le Goater
2025-10-01 17:54 ` [PATCH v2 18/18] system/physmem: Extract API out of 'system/ram_addr.h' header Philippe Mathieu-Daudé
2025-10-02 8:31 ` Cédric Le Goater
2025-10-02 8:40 ` Cédric Le Goater
2025-10-03 20:54 ` [PATCH v2 00/18] " Philippe Mathieu-Daudé
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