util: Merge cacheflush.c and cacheinfo.c

Combine the two files into cacheflush.c.  There's a couple of bits
that would be helpful to share between the two, and combining them
seems better than exporting the bits.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220621014837.189139-2-richard.henderson@linaro.org>

1 files changed, 201 insertions, 1 deletions

diff --git a/util/cacheflush.c b/util/cacheflush.c
index 4b57186d89..8096afd33c 100644
--- a/util/cacheflush.c
+++ b/util/cacheflush.c
@@ -1,5 +1,5 @@
 /*
- * Flush the host cpu caches.
+ * Info about, and flushing the host cpu caches.
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
@@ -9,8 +9,208 @@
 #include "qemu/cacheflush.h"
 #include "qemu/cacheinfo.h"
 #include "qemu/bitops.h"
+#include "qemu/host-utils.h"
+#include "qemu/atomic.h"
 
 
+int qemu_icache_linesize = 0;
+int qemu_icache_linesize_log;
+int qemu_dcache_linesize = 0;
+int qemu_dcache_linesize_log;
+
+/*
+ * Operating system specific cache detection mechanisms.
+ */
+
+#if defined(_WIN32)
+
+static void sys_cache_info(int *isize, int *dsize)
+{
+    SYSTEM_LOGICAL_PROCESSOR_INFORMATION *buf;
+    DWORD size = 0;
+    BOOL success;
+    size_t i, n;
+
+    /*
+     * Check for the required buffer size first.  Note that if the zero
+     * size we use for the probe results in success, then there is no
+     * data available; fail in that case.
+     */
+    success = GetLogicalProcessorInformation(0, &size);
+    if (success || GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
+        return;
+    }
+
+    n = size / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION);
+    size = n * sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION);
+    buf = g_new0(SYSTEM_LOGICAL_PROCESSOR_INFORMATION, n);
+    if (!GetLogicalProcessorInformation(buf, &size)) {
+        goto fail;
+    }
+
+    for (i = 0; i < n; i++) {
+        if (buf[i].Relationship == RelationCache
+            && buf[i].Cache.Level == 1) {
+            switch (buf[i].Cache.Type) {
+            case CacheUnified:
+                *isize = *dsize = buf[i].Cache.LineSize;
+                break;
+            case CacheInstruction:
+                *isize = buf[i].Cache.LineSize;
+                break;
+            case CacheData:
+                *dsize = buf[i].Cache.LineSize;
+                break;
+            default:
+                break;
+            }
+        }
+    }
+ fail:
+    g_free(buf);
+}
+
+#elif defined(__APPLE__)
+# include <sys/sysctl.h>
+static void sys_cache_info(int *isize, int *dsize)
+{
+    /* There's only a single sysctl for both I/D cache line sizes.  */
+    long size;
+    size_t len = sizeof(size);
+    if (!sysctlbyname("hw.cachelinesize", &size, &len, NULL, 0)) {
+        *isize = *dsize = size;
+    }
+}
+#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+# include <sys/sysctl.h>
+static void sys_cache_info(int *isize, int *dsize)
+{
+    /* There's only a single sysctl for both I/D cache line sizes.  */
+    int size;
+    size_t len = sizeof(size);
+    if (!sysctlbyname("machdep.cacheline_size", &size, &len, NULL, 0)) {
+        *isize = *dsize = size;
+    }
+}
+#else
+/* POSIX */
+
+static void sys_cache_info(int *isize, int *dsize)
+{
+# ifdef _SC_LEVEL1_ICACHE_LINESIZE
+    int tmp_isize = (int) sysconf(_SC_LEVEL1_ICACHE_LINESIZE);
+    if (tmp_isize > 0) {
+        *isize = tmp_isize;
+    }
+# endif
+# ifdef _SC_LEVEL1_DCACHE_LINESIZE
+    int tmp_dsize = (int) sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
+    if (tmp_dsize > 0) {
+        *dsize = tmp_dsize;
+    }
+# endif
+}
+#endif /* sys_cache_info */
+
+
+/*
+ * Architecture (+ OS) specific cache detection mechanisms.
+ */
+
+#if defined(__aarch64__)
+
+static void arch_cache_info(int *isize, int *dsize)
+{
+    if (*isize == 0 || *dsize == 0) {
+        uint64_t ctr;
+
+        /*
+         * The real cache geometry is in CCSIDR_EL1/CLIDR_EL1/CSSELR_EL1,
+         * but (at least under Linux) these are marked protected by the
+         * kernel.  However, CTR_EL0 contains the minimum linesize in the
+         * entire hierarchy, and is used by userspace cache flushing.
+         */
+        asm volatile("mrs\t%0, ctr_el0" : "=r"(ctr));
+        if (*isize == 0) {
+            *isize = 4 << (ctr & 0xf);
+        }
+        if (*dsize == 0) {
+            *dsize = 4 << ((ctr >> 16) & 0xf);
+        }
+    }
+}
+
+#elif defined(_ARCH_PPC) && defined(__linux__)
+# include "elf.h"
+
+static void arch_cache_info(int *isize, int *dsize)
+{
+    if (*isize == 0) {
+        *isize = qemu_getauxval(AT_ICACHEBSIZE);
+    }
+    if (*dsize == 0) {
+        *dsize = qemu_getauxval(AT_DCACHEBSIZE);
+    }
+}
+
+#else
+static void arch_cache_info(int *isize, int *dsize) { }
+#endif /* arch_cache_info */
+
+/*
+ * ... and if all else fails ...
+ */
+
+static void fallback_cache_info(int *isize, int *dsize)
+{
+    /* If we can only find one of the two, assume they're the same.  */
+    if (*isize) {
+        if (*dsize) {
+            /* Success! */
+        } else {
+            *dsize = *isize;
+        }
+    } else if (*dsize) {
+        *isize = *dsize;
+    } else {
+#if defined(_ARCH_PPC)
+        /*
+         * For PPC, we're going to use the cache sizes computed for
+         * flush_idcache_range.  Which means that we must use the
+         * architecture minimum.
+         */
+        *isize = *dsize = 16;
+#else
+        /* Otherwise, 64 bytes is not uncommon.  */
+        *isize = *dsize = 64;
+#endif
+    }
+}
+
+static void __attribute__((constructor)) init_cache_info(void)
+{
+    int isize = 0, dsize = 0;
+
+    sys_cache_info(&isize, &dsize);
+    arch_cache_info(&isize, &dsize);
+    fallback_cache_info(&isize, &dsize);
+
+    assert((isize & (isize - 1)) == 0);
+    assert((dsize & (dsize - 1)) == 0);
+
+    qemu_icache_linesize = isize;
+    qemu_icache_linesize_log = ctz32(isize);
+    qemu_dcache_linesize = dsize;
+    qemu_dcache_linesize_log = ctz32(dsize);
+
+    qatomic64_init();
+}
+
+
+/*
+ * Architecture (+ OS) specific cache flushing mechanisms.
+ */
+
 #if defined(__i386__) || defined(__x86_64__) || defined(__s390__)
 
 /* Caches are coherent and do not require flushing; symbol inline. */