| Message ID | 20240102015808.132373-12-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | linux-user: Improve host and guest page size handling | expand |
On 1/2/24 05:57, Richard Henderson wrote: > Replace with the maximum of the real host page size > and the target page size. This is an exact replacement. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > migration/ram.c | 22 ++++++++++++++++++---- > 1 file changed, 18 insertions(+), 4 deletions(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 8c7886ab79..aa3109fca3 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -2936,7 +2936,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque) > { > RAMState **rsp = opaque; > RAMBlock *block; > - int ret; > + int ret, max_hg_page_size; > > if (compress_threads_save_setup()) { > return -1; > @@ -2951,6 +2951,12 @@ static int ram_save_setup(QEMUFile *f, void *opaque) > } > (*rsp)->pss[RAM_CHANNEL_PRECOPY].pss_channel = f; > > + /* > + * ??? Mirrors the previous value of qemu_host_page_size, > + * but is this really what was intended for the migration? > + */ > + max_hg_page_size = MAX(qemu_real_host_page_size(), TARGET_PAGE_SIZE); > + > WITH_RCU_READ_LOCK_GUARD() { > qemu_put_be64(f, ram_bytes_total_with_ignored() > | RAM_SAVE_FLAG_MEM_SIZE); > @@ -2959,8 +2965,8 @@ static int ram_save_setup(QEMUFile *f, void *opaque) > qemu_put_byte(f, strlen(block->idstr)); > qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); > qemu_put_be64(f, block->used_length); > - if (migrate_postcopy_ram() && block->page_size != > - qemu_host_page_size) { > + if (migrate_postcopy_ram() && > + block->page_size != max_hg_page_size) { > qemu_put_be64(f, block->page_size); > } > if (migrate_ignore_shared()) { > @@ -3794,6 +3800,7 @@ static int parse_ramblock(QEMUFile *f, RAMBlock *block, ram_addr_t length) > int ret = 0; > /* ADVISE is earlier, it shows the source has the postcopy capability on */ > bool postcopy_advised = migration_incoming_postcopy_advised(); > + int max_hg_page_size; > > assert(block); > > @@ -3811,9 +3818,16 @@ static int parse_ramblock(QEMUFile *f, RAMBlock *block, ram_addr_t length) > return ret; > } > } > + > + /* > + * ??? Mirrors the previous value of qemu_host_page_size, > + * but is this really what was intended for the migration? > + */ > + max_hg_page_size = MAX(qemu_real_host_page_size(), TARGET_PAGE_SIZE); > + > /* For postcopy we need to check hugepage sizes match */ > if (postcopy_advised && migrate_postcopy_ram() && > - block->page_size != qemu_host_page_size) { > + block->page_size != max_hg_page_size) { > uint64_t remote_page_size = qemu_get_be64(f); > if (remote_page_size != block->page_size) { > error_report("Mismatched RAM page size %s " Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
On Tue, Jan 02, 2024 at 12:57:46PM +1100, Richard Henderson wrote: > Replace with the maximum of the real host page size > and the target page size. This is an exact replacement. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > migration/ram.c | 22 ++++++++++++++++++---- > 1 file changed, 18 insertions(+), 4 deletions(-) Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
diff --git a/migration/ram.c b/migration/ram.c index 8c7886ab79..aa3109fca3 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2936,7 +2936,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque) { RAMState **rsp = opaque; RAMBlock *block; - int ret; + int ret, max_hg_page_size; if (compress_threads_save_setup()) { return -1; @@ -2951,6 +2951,12 @@ static int ram_save_setup(QEMUFile *f, void *opaque) } (*rsp)->pss[RAM_CHANNEL_PRECOPY].pss_channel = f; + /* + * ??? Mirrors the previous value of qemu_host_page_size, + * but is this really what was intended for the migration? + */ + max_hg_page_size = MAX(qemu_real_host_page_size(), TARGET_PAGE_SIZE); + WITH_RCU_READ_LOCK_GUARD() { qemu_put_be64(f, ram_bytes_total_with_ignored() | RAM_SAVE_FLAG_MEM_SIZE); @@ -2959,8 +2965,8 @@ static int ram_save_setup(QEMUFile *f, void *opaque) qemu_put_byte(f, strlen(block->idstr)); qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); qemu_put_be64(f, block->used_length); - if (migrate_postcopy_ram() && block->page_size != - qemu_host_page_size) { + if (migrate_postcopy_ram() && + block->page_size != max_hg_page_size) { qemu_put_be64(f, block->page_size); } if (migrate_ignore_shared()) { @@ -3794,6 +3800,7 @@ static int parse_ramblock(QEMUFile *f, RAMBlock *block, ram_addr_t length) int ret = 0; /* ADVISE is earlier, it shows the source has the postcopy capability on */ bool postcopy_advised = migration_incoming_postcopy_advised(); + int max_hg_page_size; assert(block); @@ -3811,9 +3818,16 @@ static int parse_ramblock(QEMUFile *f, RAMBlock *block, ram_addr_t length) return ret; } } + + /* + * ??? Mirrors the previous value of qemu_host_page_size, + * but is this really what was intended for the migration? + */ + max_hg_page_size = MAX(qemu_real_host_page_size(), TARGET_PAGE_SIZE); + /* For postcopy we need to check hugepage sizes match */ if (postcopy_advised && migrate_postcopy_ram() && - block->page_size != qemu_host_page_size) { + block->page_size != max_hg_page_size) { uint64_t remote_page_size = qemu_get_be64(f); if (remote_page_size != block->page_size) { error_report("Mismatched RAM page size %s "
Replace with the maximum of the real host page size and the target page size. This is an exact replacement. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- migration/ram.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)