From: Andreas Färber Date: Sat, 25 Sep 2010 11:26:05 +0000 (+0000) Subject: Introduce qemu_madvise() X-Git-Tag: TizenStudio_2.0_p2.3.2~208^2~7143 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e78815a554adaa551d62a71be10ee2fcf128e473;p=sdk%2Femulator%2Fqemu.git Introduce qemu_madvise() vl.c has a Sun-specific hack to supply a prototype for madvise(), but the call site has apparently moved to arch_init.c. Haiku doesn't implement madvise() in favor of posix_madvise(). OpenBSD and Solaris 10 don't implement posix_madvise() but madvise(). MinGW implements neither. Check for madvise() and posix_madvise() in configure and supply qemu_madvise() as wrapper. Prefer madvise() over posix_madvise() due to flag availability. Convert all callers to use qemu_madvise() and QEMU_MADV_*. Note that on Solaris the warning is fixed by moving the madvise() prototype, not by qemu_madvise() itself. It helps with porting though, and it simplifies most call sites. v7 -> v8: * Some versions of MinGW have no sys/mman.h header. Reported by Blue Swirl. v6 -> v7: * Adopt madvise() rather than posix_madvise() semantics for returning errors. * Use EINVAL in place of ENOTSUP. v5 -> v6: * Replace two leftover instances of POSIX_MADV_NORMAL with QEMU_MADV_INVALID. Spotted by Blue Swirl. v4 -> v5: * Introduce QEMU_MADV_INVALID, suggested by Alexander Graf. Note that this relies on -1 not being a valid advice value. v3 -> v4: * Eliminate #ifdefs at qemu_advise() call sites. Requested by Blue Swirl. This will currently break the check in kvm-all.c by calling madvise() with a supported flag, which will not fail. Ideas/patches welcome. v2 -> v3: * Reuse the *_MADV_* defines for QEMU_MADV_*. Suggested by Alexander Graf. * Add configure check for madvise(), too. Add defines to Makefile, not QEMU_CFLAGS. Convert all callers, untested. Suggested by Blue Swirl. * Keep Solaris' madvise() prototype around. Pointed out by Alexander Graf. * Display configure check results. v1 -> v2: * Don't rely on posix_madvise() availability, add qemu_madvise(). Suggested by Blue Swirl. Signed-off-by: Andreas Färber Cc: Blue Swirl Cc: Alexander Graf Cc: Andrea Arcangeli Signed-off-by: Blue Swirl --- diff --git a/arch_init.c b/arch_init.c index e468c0c..a910033 100644 --- a/arch_init.c +++ b/arch_init.c @@ -396,7 +396,7 @@ int ram_load(QEMUFile *f, void *opaque, int version_id) #ifndef _WIN32 if (ch == 0 && (!kvm_enabled() || kvm_has_sync_mmu())) { - madvise(host, TARGET_PAGE_SIZE, MADV_DONTNEED); + qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED); } #endif } else if (flags & RAM_SAVE_FLAG_PAGE) { diff --git a/configure b/configure index 3bfc5e9..6a21bf2 100755 --- a/configure +++ b/configure @@ -2072,6 +2072,31 @@ if compile_prog "" "" ; then fi ########################################## +# check if we have madvise + +madvise=no +cat > $TMPC << EOF +#include +#include +int main(void) { return madvise(NULL, 0, MADV_DONTNEED); } +EOF +if compile_prog "" "" ; then + madvise=yes +fi + +########################################## +# check if we have posix_madvise + +posix_madvise=no +cat > $TMPC << EOF +#include +int main(void) { return posix_madvise(NULL, 0, POSIX_MADV_DONTNEED); } +EOF +if compile_prog "" "" ; then + posix_madvise=yes +fi + +########################################## # check if trace backend exists sh "$source_path/tracetool" "--$trace_backend" --check-backend > /dev/null 2> /dev/null @@ -2238,6 +2263,8 @@ echo "KVM support $kvm" echo "fdt support $fdt" echo "preadv support $preadv" echo "fdatasync $fdatasync" +echo "madvise $madvise" +echo "posix_madvise $posix_madvise" echo "uuid support $uuid" echo "vhost-net support $vhost_net" echo "Trace backend $trace_backend" @@ -2478,6 +2505,12 @@ fi if test "$fdatasync" = "yes" ; then echo "CONFIG_FDATASYNC=y" >> $config_host_mak fi +if test "$madvise" = "yes" ; then + echo "CONFIG_MADVISE=y" >> $config_host_mak +fi +if test "$posix_madvise" = "yes" ; then + echo "CONFIG_POSIX_MADVISE=y" >> $config_host_mak +fi # XXX: suppress that if [ "$bsd" = "yes" ] ; then diff --git a/exec.c b/exec.c index 380dab5..9b5464f 100644 --- a/exec.c +++ b/exec.c @@ -2841,9 +2841,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name, new_block->host = file_ram_alloc(new_block, size, mem_path); if (!new_block->host) { new_block->host = qemu_vmalloc(size); -#ifdef MADV_MERGEABLE - madvise(new_block->host, size, MADV_MERGEABLE); -#endif + qemu_madvise(new_block->host, size, QEMU_MADV_MERGEABLE); } #else fprintf(stderr, "-mem-path option unsupported\n"); @@ -2858,9 +2856,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name, #else new_block->host = qemu_vmalloc(size); #endif -#ifdef MADV_MERGEABLE - madvise(new_block->host, size, MADV_MERGEABLE); -#endif + qemu_madvise(new_block->host, size, QEMU_MADV_MERGEABLE); } } diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c index 9fe3886..1e74674 100644 --- a/hw/virtio-balloon.c +++ b/hw/virtio-balloon.c @@ -51,8 +51,8 @@ static void balloon_page(void *addr, int deflate) { #if defined(__linux__) if (!kvm_enabled() || kvm_has_sync_mmu()) - madvise(addr, TARGET_PAGE_SIZE, - deflate ? MADV_WILLNEED : MADV_DONTNEED); + qemu_madvise(addr, TARGET_PAGE_SIZE, + deflate ? QEMU_MADV_WILLNEED : QEMU_MADV_DONTNEED); #endif } diff --git a/kvm-all.c b/kvm-all.c index 58b0404..1cc696f 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -1031,18 +1031,14 @@ int kvm_has_xcrs(void) void kvm_setup_guest_memory(void *start, size_t size) { if (!kvm_has_sync_mmu()) { -#ifdef MADV_DONTFORK - int ret = madvise(start, size, MADV_DONTFORK); + int ret = qemu_madvise(start, size, QEMU_MADV_DONTFORK); if (ret) { - perror("madvice"); + perror("qemu_madvise"); + fprintf(stderr, + "Need MADV_DONTFORK in absence of synchronous KVM MMU\n"); exit(1); } -#else - fprintf(stderr, - "Need MADV_DONTFORK in absence of synchronous KVM MMU\n"); - exit(1); -#endif } } diff --git a/osdep.c b/osdep.c index 30426ff..2e05b21 100644 --- a/osdep.c +++ b/osdep.c @@ -32,9 +32,16 @@ /* Needed early for CONFIG_BSD etc. */ #include "config-host.h" +#if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE) +#include +#endif + #ifdef CONFIG_SOLARIS #include #include +/* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for + discussion about Solaris header problems */ +extern int madvise(caddr_t, size_t, int); #endif #ifdef CONFIG_EVENTFD @@ -139,6 +146,22 @@ void qemu_vfree(void *ptr) #endif +int qemu_madvise(void *addr, size_t len, int advice) +{ + if (advice == QEMU_MADV_INVALID) { + errno = EINVAL; + return -1; + } +#if defined(CONFIG_MADVISE) + return madvise(addr, len, advice); +#elif defined(CONFIG_POSIX_MADVISE) + return posix_madvise(addr, len, advice); +#else + errno = EINVAL; + return -1; +#endif +} + int qemu_create_pidfile(const char *filename) { char buffer[128]; diff --git a/osdep.h b/osdep.h index 1cdc7e2..6716281 100644 --- a/osdep.h +++ b/osdep.h @@ -90,6 +90,41 @@ void *qemu_memalign(size_t alignment, size_t size); void *qemu_vmalloc(size_t size); void qemu_vfree(void *ptr); +#define QEMU_MADV_INVALID -1 + +#if defined(CONFIG_MADVISE) + +#define QEMU_MADV_WILLNEED MADV_WILLNEED +#define QEMU_MADV_DONTNEED MADV_DONTNEED +#ifdef MADV_DONTFORK +#define QEMU_MADV_DONTFORK MADV_DONTFORK +#else +#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID +#endif +#ifdef MADV_MERGEABLE +#define QEMU_MADV_MERGEABLE MADV_MERGEABLE +#else +#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID +#endif + +#elif defined(CONFIG_POSIX_MADVISE) + +#define QEMU_MADV_WILLNEED POSIX_MADV_WILLNEED +#define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED +#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID +#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID + +#else /* no-op */ + +#define QEMU_MADV_WILLNEED QEMU_MADV_INVALID +#define QEMU_MADV_DONTNEED QEMU_MADV_INVALID +#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID +#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID + +#endif + +int qemu_madvise(void *addr, size_t len, int advice); + int qemu_create_pidfile(const char *filename); #ifdef _WIN32 diff --git a/vl.c b/vl.c index 3f45aa9..d352d18 100644 --- a/vl.c +++ b/vl.c @@ -80,9 +80,6 @@ #include #include #include -/* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for - discussion about Solaris header problems */ -extern int madvise(caddr_t, size_t, int); #endif #endif #endif