| Message ID | 20190910095610.4546-3-beata.michalska@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | target/arm: Support for Data Cache Clean up to PoP | expand |
Beata Michalska <beata.michalska@linaro.org> writes: > Add an option to trigger memory writeback to sync given memory region > with the corresponding backing store, case one is available. > This extends the support for persistent memory, allowing syncing on-demand. > > Also, adding verification for msync support on host. > > Signed-off-by: Beata Michalska <beata.michalska@linaro.org> > --- > configure | 24 ++++++++++++++++++++++++ > exec.c | 38 ++++++++++++++++++++++++++++++++++++++ > include/exec/memory.h | 6 ++++++ > include/exec/ram_addr.h | 6 ++++++ > memory.c | 12 ++++++++++++ > 5 files changed, 86 insertions(+) > > diff --git a/configure b/configure > index 95134c0180..bdb7dc47e9 100755 > --- a/configure > +++ b/configure > @@ -5081,6 +5081,26 @@ if compile_prog "" "" ; then > fdatasync=yes > fi > > +########################################## > +# verify support for msyc > + > +msync=no > +cat > $TMPC << EOF > +#include <unistd.h> > +#include <sys/mman.h> > +int main(void) { > +#if defined(_POSIX_MAPPED_FILES) && _POSIX_MAPPED_FILES > 0 \ > +&& defined(_POSIX_SYNCHRONIZED_IO) && _POSIX_SYNCHRONIZED_IO > 0 > +return msync(NULL,0, MS_SYNC); > +#else > +#error Not supported > +#endif > +} > +EOF > +if compile_prog "" "" ; then > + msync=yes > +fi > + > ########################################## > # check if we have madvise > > @@ -6413,6 +6433,7 @@ echo "fdt support $fdt" > echo "membarrier $membarrier" > echo "preadv support $preadv" > echo "fdatasync $fdatasync" > +echo "msync $msync" > echo "madvise $madvise" > echo "posix_madvise $posix_madvise" > echo "posix_memalign $posix_memalign" > @@ -6952,6 +6973,9 @@ fi > if test "$fdatasync" = "yes" ; then > echo "CONFIG_FDATASYNC=y" >> $config_host_mak > fi > +if test "$msync" = "yes" ; then > + echo "CONFIG_MSYNC=y" >> $config_host_mak > +fi I think it's best to split this configure check into a new prequel patch and... > if test "$madvise" = "yes" ; then > echo "CONFIG_MADVISE=y" >> $config_host_mak > fi > diff --git a/exec.c b/exec.c > index 235d6bc883..5ed6908368 100644 > --- a/exec.c > +++ b/exec.c > @@ -65,6 +65,8 @@ > #include "exec/ram_addr.h" > #include "exec/log.h" > > +#include "qemu/pmem.h" > + > #include "migration/vmstate.h" > > #include "qemu/range.h" > @@ -2182,6 +2184,42 @@ int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp) > return 0; > } > > +/* > + * Trigger sync on the given ram block for range [start, start + length] > + * with the backing store if available. > + * @Note: this is supposed to be a SYNC op. > + */ > +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length) > +{ > + void *addr = ramblock_ptr(block, start); > + > + /* > + * The requested range might spread up to the very end of the block > + */ > + if ((start + length) > block->used_length) { > + error_report("%s: sync range outside the block boundires: " > + "start: " RAM_ADDR_FMT " length: " RAM_ADDR_FMT > + " block length: " RAM_ADDR_FMT " Narrowing down ..." , > + __func__, start, length, block->used_length); Is this an error or just logging? error_report should be used for stuff that the user needs to know about so it will appear on the HMP console (or via stderr). If so what is the user expected to do? Have they misconfigured their system? > + length = block->used_length - start; > + } > + > +#ifdef CONFIG_LIBPMEM > + /* The lack of support for pmem should not block the sync */ > + if (ramblock_is_pmem(block)) { > + pmem_persist(addr, length); > + } else > +#endif > + if (block->fd >= 0) { > +#ifdef CONFIG_MSYNC > + msync((void *)((uintptr_t)addr & qemu_host_page_mask), > + HOST_PAGE_ALIGN(length), MS_SYNC); > +#else > + qemu_fdatasync(block->fd); > +#endif ... hide the implementation details in util/cutils.c, maybe as qemu_msync()? > + } > +} > + > /* Called with ram_list.mutex held */ > static void dirty_memory_extend(ram_addr_t old_ram_size, > ram_addr_t new_ram_size) > diff --git a/include/exec/memory.h b/include/exec/memory.h > index 2dd810259d..ff0d7937cf 100644 > --- a/include/exec/memory.h > +++ b/include/exec/memory.h > @@ -1242,6 +1242,12 @@ void *memory_region_get_ram_ptr(MemoryRegion *mr); > */ > void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize, > Error **errp); > +/** > + * memory_region_do_writeback: Trigger writeback for selected address range > + * [addr, addr + size] > + * > + */ > +void memory_region_do_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size); > > /** > * memory_region_set_log: Turn dirty logging on or off for a region. > diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h > index a327a80cfe..d4bce81a03 100644 > --- a/include/exec/ram_addr.h > +++ b/include/exec/ram_addr.h > @@ -180,6 +180,12 @@ void qemu_ram_free(RAMBlock *block); > > int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp); > > +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length); > + > +/* Clear whole block of mem */ > +#define qemu_ram_block_writeback(rb) \ > + qemu_ram_writeback(rb, 0, rb->used_length) > + > #define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1) > #define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE)) > > diff --git a/memory.c b/memory.c > index 61a254c3f9..436eb64737 100644 > --- a/memory.c > +++ b/memory.c > @@ -2228,6 +2228,18 @@ void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize, Error **errp > qemu_ram_resize(mr->ram_block, newsize, errp); > } > > + > +void memory_region_do_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size) > +{ > + /* > + * Might be extended case needed to cover > + * different types of memory regions > + */ > + if (mr->ram_block && mr->dirty_log_mask) { > + qemu_ram_writeback(mr->ram_block, addr, size); > + } > +} > + > /* > * Call proper memory listeners about the change on the newly > * added/removed CoalescedMemoryRange. -- Alex Bennée
On 9/10/19 2:56 AM, Beata Michalska wrote: > +int main(void) { > +#if defined(_POSIX_MAPPED_FILES) && _POSIX_MAPPED_FILES > 0 \ > +&& defined(_POSIX_SYNCHRONIZED_IO) && _POSIX_SYNCHRONIZED_IO > 0 > +return msync(NULL,0, MS_SYNC); > +#else > +#error Not supported > +#endif > +} Is there any particular reason to check _POSIX_MAPPED_FILES & _POSIX_SYNCHRONIZED_IO? IIRC, you can use those to "safely" use MS_SYNC. But this is a configure test, and an error is in fact our defined failure case, so "safely" doesn't seem particularly relevant. Alternately, do we even support any systems (besides perhaps windows) that do not provide POSIX-2001 support, and so include msync + MS_SYNC? My first guess is that we don't. > + msync((void *)((uintptr_t)addr & qemu_host_page_mask), > + HOST_PAGE_ALIGN(length), MS_SYNC); This isn't quite right. If you move addr down to a lower address via this page mask, you must also increase length by the same amount, and only afterward increase length to the host page size. Consider addr == 0xffffff, length = 2. This covers two pages, so you'd expect the final parameters to be, for 4k page size, 0xfff000, 0x2000. r~
On 9/10/19 2:56 AM, Beata Michalska wrote: > +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length); > + > +/* Clear whole block of mem */ > +#define qemu_ram_block_writeback(rb) \ > + qemu_ram_writeback(rb, 0, rb->used_length) > + Inline function, with its typechecking, is preferred. r~
On Tue, 24 Sep 2019 at 01:00, Alex Bennée <alex.bennee@linaro.org> wrote: > > > Beata Michalska <beata.michalska@linaro.org> writes: > > > Add an option to trigger memory writeback to sync given memory region > > with the corresponding backing store, case one is available. > > This extends the support for persistent memory, allowing syncing on-demand. > > > > Also, adding verification for msync support on host. > > > > Signed-off-by: Beata Michalska <beata.michalska@linaro.org> > > --- > > configure | 24 ++++++++++++++++++++++++ > > exec.c | 38 ++++++++++++++++++++++++++++++++++++++ > > include/exec/memory.h | 6 ++++++ > > include/exec/ram_addr.h | 6 ++++++ > > memory.c | 12 ++++++++++++ > > 5 files changed, 86 insertions(+) > > > > diff --git a/configure b/configure > > index 95134c0180..bdb7dc47e9 100755 > > --- a/configure > > +++ b/configure > > @@ -5081,6 +5081,26 @@ if compile_prog "" "" ; then > > fdatasync=yes > > fi > > > > +########################################## > > +# verify support for msyc > > + > > +msync=no > > +cat > $TMPC << EOF > > +#include <unistd.h> > > +#include <sys/mman.h> > > +int main(void) { > > +#if defined(_POSIX_MAPPED_FILES) && _POSIX_MAPPED_FILES > 0 \ > > +&& defined(_POSIX_SYNCHRONIZED_IO) && _POSIX_SYNCHRONIZED_IO > 0 > > +return msync(NULL,0, MS_SYNC); > > +#else > > +#error Not supported > > +#endif > > +} > > +EOF > > +if compile_prog "" "" ; then > > + msync=yes > > +fi > > + > > ########################################## > > # check if we have madvise > > > > @@ -6413,6 +6433,7 @@ echo "fdt support $fdt" > > echo "membarrier $membarrier" > > echo "preadv support $preadv" > > echo "fdatasync $fdatasync" > > +echo "msync $msync" > > echo "madvise $madvise" > > echo "posix_madvise $posix_madvise" > > echo "posix_memalign $posix_memalign" > > @@ -6952,6 +6973,9 @@ fi > > if test "$fdatasync" = "yes" ; then > > echo "CONFIG_FDATASYNC=y" >> $config_host_mak > > fi > > +if test "$msync" = "yes" ; then > > + echo "CONFIG_MSYNC=y" >> $config_host_mak > > +fi > > I think it's best to split this configure check into a new prequel patch and... I might just drop it in favour of CONFIG_POSIX switch ...... > > > if test "$madvise" = "yes" ; then > > echo "CONFIG_MADVISE=y" >> $config_host_mak > > fi > > diff --git a/exec.c b/exec.c > > index 235d6bc883..5ed6908368 100644 > > --- a/exec.c > > +++ b/exec.c > > @@ -65,6 +65,8 @@ > > #include "exec/ram_addr.h" > > #include "exec/log.h" > > > > +#include "qemu/pmem.h" > > + > > #include "migration/vmstate.h" > > > > #include "qemu/range.h" > > @@ -2182,6 +2184,42 @@ int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp) > > return 0; > > } > > > > +/* > > + * Trigger sync on the given ram block for range [start, start + length] > > + * with the backing store if available. > > + * @Note: this is supposed to be a SYNC op. > > + */ > > +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length) > > +{ > > + void *addr = ramblock_ptr(block, start); > > + > > + /* > > + * The requested range might spread up to the very end of the block > > + */ > > + if ((start + length) > block->used_length) { > > + error_report("%s: sync range outside the block boundires: " > > + "start: " RAM_ADDR_FMT " length: " RAM_ADDR_FMT > > + " block length: " RAM_ADDR_FMT " Narrowing down ..." , > > + __func__, start, length, block->used_length); > > Is this an error or just logging? error_report should be used for stuff > that the user needs to know about so it will appear on the HMP console > (or via stderr). If so what is the user expected to do? Have they > misconfigured their system? > This should be logging rather than 'error reporting as such. My bad. Will address that in the next version. > > + length = block->used_length - start; > > + } > > + > > +#ifdef CONFIG_LIBPMEM > > + /* The lack of support for pmem should not block the sync */ > > + if (ramblock_is_pmem(block)) { > > + pmem_persist(addr, length); > > + } else > > +#endif > > + if (block->fd >= 0) { > > +#ifdef CONFIG_MSYNC > > + msync((void *)((uintptr_t)addr & qemu_host_page_mask), > > + HOST_PAGE_ALIGN(length), MS_SYNC); > > +#else > > + qemu_fdatasync(block->fd); > > +#endif > > ... hide the implementation details in util/cutils.c, maybe as > qemu_msync()? > > > + } > > +} > > + > > /* Called with ram_list.mutex held */ > > static void dirty_memory_extend(ram_addr_t old_ram_size, > > ram_addr_t new_ram_size) > > diff --git a/include/exec/memory.h b/include/exec/memory.h > > index 2dd810259d..ff0d7937cf 100644 > > --- a/include/exec/memory.h > > +++ b/include/exec/memory.h > > @@ -1242,6 +1242,12 @@ void *memory_region_get_ram_ptr(MemoryRegion *mr); > > */ > > void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize, > > Error **errp); > > +/** > > + * memory_region_do_writeback: Trigger writeback for selected address range > > + * [addr, addr + size] > > + * > > + */ > > +void memory_region_do_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size); > > > > /** > > * memory_region_set_log: Turn dirty logging on or off for a region. > > diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h > > index a327a80cfe..d4bce81a03 100644 > > --- a/include/exec/ram_addr.h > > +++ b/include/exec/ram_addr.h > > @@ -180,6 +180,12 @@ void qemu_ram_free(RAMBlock *block); > > > > int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp); > > > > +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length); > > + > > +/* Clear whole block of mem */ > > +#define qemu_ram_block_writeback(rb) \ > > + qemu_ram_writeback(rb, 0, rb->used_length) > > + > > #define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1) > > #define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE)) > > > > diff --git a/memory.c b/memory.c > > index 61a254c3f9..436eb64737 100644 > > --- a/memory.c > > +++ b/memory.c > > @@ -2228,6 +2228,18 @@ void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize, Error **errp > > qemu_ram_resize(mr->ram_block, newsize, errp); > > } > > > > + > > +void memory_region_do_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size) > > +{ > > + /* > > + * Might be extended case needed to cover > > + * different types of memory regions > > + */ > > + if (mr->ram_block && mr->dirty_log_mask) { > > + qemu_ram_writeback(mr->ram_block, addr, size); > > + } > > +} > > + > > /* > > * Call proper memory listeners about the change on the newly > > * added/removed CoalescedMemoryRange. > > > -- > Alex Bennée Thank you. BR Beata
On Tue, 24 Sep 2019 at 17:28, Richard Henderson <richard.henderson@linaro.org> wrote: > > On 9/10/19 2:56 AM, Beata Michalska wrote: > > +int main(void) { > > +#if defined(_POSIX_MAPPED_FILES) && _POSIX_MAPPED_FILES > 0 \ > > +&& defined(_POSIX_SYNCHRONIZED_IO) && _POSIX_SYNCHRONIZED_IO > 0 > > +return msync(NULL,0, MS_SYNC); > > +#else > > +#error Not supported > > +#endif > > +} > > Is there any particular reason to check _POSIX_MAPPED_FILES & > _POSIX_SYNCHRONIZED_IO? IIRC, you can use those to "safely" use MS_SYNC. But > this is a configure test, and an error is in fact our defined failure case, so > "safely" doesn't seem particularly relevant. > > Alternately, do we even support any systems (besides perhaps windows) that do > not provide POSIX-2001 support, and so include msync + MS_SYNC? My first guess > is that we don't. > Both flags are there to verify support for msync itself. The check there is for posix systems , where if both set to value greater than '0' the msync call is available. AFAIK Windows is the only posix non-compliant system being supported . Though I might be wrong (?) I might just drop the check here and use CONFIG_POSIX to handle the msync call instead. > > + msync((void *)((uintptr_t)addr & qemu_host_page_mask), > > + HOST_PAGE_ALIGN(length), MS_SYNC); > > This isn't quite right. If you move addr down to a lower address via this page > mask, you must also increase length by the same amount, and only afterward > increase length to the host page size. > > Consider addr == 0xffffff, length = 2. This covers two pages, so you'd expect > the final parameters to be, for 4k page size, 0xfff000, 0x2000. > Thanks for catching this - guess I was too focused on the cache line size, which would not cross page boundaries. Will fix that in the next version. > r~ Thank you. BR Beata
On Tue, 24 Sep 2019 at 17:30, Richard Henderson <richard.henderson@linaro.org> wrote: > > On 9/10/19 2:56 AM, Beata Michalska wrote: > > +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length); > > + > > +/* Clear whole block of mem */ > > +#define qemu_ram_block_writeback(rb) \ > > + qemu_ram_writeback(rb, 0, rb->used_length) > > + > > Inline function, with its typechecking, is preferred. > > Noted. To be fixed in the next version. BR Beata > r~
diff --git a/configure b/configure index 95134c0180..bdb7dc47e9 100755 --- a/configure +++ b/configure @@ -5081,6 +5081,26 @@ if compile_prog "" "" ; then fdatasync=yes fi +########################################## +# verify support for msyc + +msync=no +cat > $TMPC << EOF +#include <unistd.h> +#include <sys/mman.h> +int main(void) { +#if defined(_POSIX_MAPPED_FILES) && _POSIX_MAPPED_FILES > 0 \ +&& defined(_POSIX_SYNCHRONIZED_IO) && _POSIX_SYNCHRONIZED_IO > 0 +return msync(NULL,0, MS_SYNC); +#else +#error Not supported +#endif +} +EOF +if compile_prog "" "" ; then + msync=yes +fi + ########################################## # check if we have madvise @@ -6413,6 +6433,7 @@ echo "fdt support $fdt" echo "membarrier $membarrier" echo "preadv support $preadv" echo "fdatasync $fdatasync" +echo "msync $msync" echo "madvise $madvise" echo "posix_madvise $posix_madvise" echo "posix_memalign $posix_memalign" @@ -6952,6 +6973,9 @@ fi if test "$fdatasync" = "yes" ; then echo "CONFIG_FDATASYNC=y" >> $config_host_mak fi +if test "$msync" = "yes" ; then + echo "CONFIG_MSYNC=y" >> $config_host_mak +fi if test "$madvise" = "yes" ; then echo "CONFIG_MADVISE=y" >> $config_host_mak fi diff --git a/exec.c b/exec.c index 235d6bc883..5ed6908368 100644 --- a/exec.c +++ b/exec.c @@ -65,6 +65,8 @@ #include "exec/ram_addr.h" #include "exec/log.h" +#include "qemu/pmem.h" + #include "migration/vmstate.h" #include "qemu/range.h" @@ -2182,6 +2184,42 @@ int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp) return 0; } +/* + * Trigger sync on the given ram block for range [start, start + length] + * with the backing store if available. + * @Note: this is supposed to be a SYNC op. + */ +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length) +{ + void *addr = ramblock_ptr(block, start); + + /* + * The requested range might spread up to the very end of the block + */ + if ((start + length) > block->used_length) { + error_report("%s: sync range outside the block boundires: " + "start: " RAM_ADDR_FMT " length: " RAM_ADDR_FMT + " block length: " RAM_ADDR_FMT " Narrowing down ..." , + __func__, start, length, block->used_length); + length = block->used_length - start; + } + +#ifdef CONFIG_LIBPMEM + /* The lack of support for pmem should not block the sync */ + if (ramblock_is_pmem(block)) { + pmem_persist(addr, length); + } else +#endif + if (block->fd >= 0) { +#ifdef CONFIG_MSYNC + msync((void *)((uintptr_t)addr & qemu_host_page_mask), + HOST_PAGE_ALIGN(length), MS_SYNC); +#else + qemu_fdatasync(block->fd); +#endif + } +} + /* Called with ram_list.mutex held */ static void dirty_memory_extend(ram_addr_t old_ram_size, ram_addr_t new_ram_size) diff --git a/include/exec/memory.h b/include/exec/memory.h index 2dd810259d..ff0d7937cf 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -1242,6 +1242,12 @@ void *memory_region_get_ram_ptr(MemoryRegion *mr); */ void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize, Error **errp); +/** + * memory_region_do_writeback: Trigger writeback for selected address range + * [addr, addr + size] + * + */ +void memory_region_do_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size); /** * memory_region_set_log: Turn dirty logging on or off for a region. diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index a327a80cfe..d4bce81a03 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -180,6 +180,12 @@ void qemu_ram_free(RAMBlock *block); int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp); +void qemu_ram_writeback(RAMBlock *block, ram_addr_t start, ram_addr_t length); + +/* Clear whole block of mem */ +#define qemu_ram_block_writeback(rb) \ + qemu_ram_writeback(rb, 0, rb->used_length) + #define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1) #define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE)) diff --git a/memory.c b/memory.c index 61a254c3f9..436eb64737 100644 --- a/memory.c +++ b/memory.c @@ -2228,6 +2228,18 @@ void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize, Error **errp qemu_ram_resize(mr->ram_block, newsize, errp); } + +void memory_region_do_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size) +{ + /* + * Might be extended case needed to cover + * different types of memory regions + */ + if (mr->ram_block && mr->dirty_log_mask) { + qemu_ram_writeback(mr->ram_block, addr, size); + } +} + /* * Call proper memory listeners about the change on the newly * added/removed CoalescedMemoryRange.
Add an option to trigger memory writeback to sync given memory region with the corresponding backing store, case one is available. This extends the support for persistent memory, allowing syncing on-demand. Also, adding verification for msync support on host. Signed-off-by: Beata Michalska <beata.michalska@linaro.org> --- configure | 24 ++++++++++++++++++++++++ exec.c | 38 ++++++++++++++++++++++++++++++++++++++ include/exec/memory.h | 6 ++++++ include/exec/ram_addr.h | 6 ++++++ memory.c | 12 ++++++++++++ 5 files changed, 86 insertions(+)