Merge "riscv64: pass a pointer to __riscv_hwprobe() to ifunc resolvers." into main am: 75539ab928

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2860689

Change-Id: I08da51a32b58320f62a2b6fbb09187e8049f243d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
This commit is contained in:
Elliott Hughes 2023-12-06 19:46:17 +00:00 committed by Automerger Merge Worker
commit aecaca71a4
3 changed files with 22 additions and 9 deletions

View file

@ -28,6 +28,7 @@
#include "private/bionic_call_ifunc_resolver.h" #include "private/bionic_call_ifunc_resolver.h"
#include <sys/auxv.h> #include <sys/auxv.h>
#include <sys/hwprobe.h>
#include <sys/ifunc.h> #include <sys/ifunc.h>
#include "bionic/macros.h" #include "bionic/macros.h"
@ -54,12 +55,12 @@ ElfW(Addr) __bionic_call_ifunc_resolver(ElfW(Addr) resolver_addr) {
static unsigned long hwcap = getauxval(AT_HWCAP); static unsigned long hwcap = getauxval(AT_HWCAP);
return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(hwcap); return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(hwcap);
#elif defined(__riscv) #elif defined(__riscv)
// The pointer argument is currently unused, but reserved for future // The third argument is currently unused, but reserved for future
// expansion. If we pass nullptr from the beginning, it'll be easier // expansion. If we pass nullptr from the beginning, it'll be easier
// to recognize if/when we pass actual data (and matches glibc). // to recognize if/when we pass actual data (and matches glibc).
typedef ElfW(Addr) (*ifunc_resolver_t)(uint64_t, void*); typedef ElfW(Addr) (*ifunc_resolver_t)(uint64_t, __riscv_hwprobe_t, void*);
static uint64_t hwcap = getauxval(AT_HWCAP); static uint64_t hwcap = getauxval(AT_HWCAP);
return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(hwcap, nullptr); return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(hwcap, __riscv_hwprobe, nullptr);
#else #else
typedef ElfW(Addr) (*ifunc_resolver_t)(void); typedef ElfW(Addr) (*ifunc_resolver_t)(void);
return reinterpret_cast<ifunc_resolver_t>(resolver_addr)(); return reinterpret_cast<ifunc_resolver_t>(resolver_addr)();

View file

@ -53,6 +53,14 @@ __BEGIN_DECLS
*/ */
int __riscv_hwprobe(struct riscv_hwprobe* _Nonnull __pairs, size_t __pair_count, size_t __cpu_count, unsigned long* _Nullable __cpus, unsigned __flags); int __riscv_hwprobe(struct riscv_hwprobe* _Nonnull __pairs, size_t __pair_count, size_t __cpu_count, unsigned long* _Nullable __cpus, unsigned __flags);
/**
* The type of the second argument passed to riscv64 ifunc resolvers.
* This argument allows riscv64 ifunc resolvers to call __riscv_hwprobe()
* without worrying about whether that relocation is resolved before
* the ifunc resolver is called.
*/
typedef int (*__riscv_hwprobe_t)(struct riscv_hwprobe* _Nonnull __pairs, size_t __pair_count, size_t __cpu_count, unsigned long* _Nullable __cpus, unsigned __flags);
__END_DECLS __END_DECLS
#endif #endif

View file

@ -65,18 +65,18 @@ extern "C" fn_ptr_t hwcap_resolver(unsigned long hwcap) {
#include <sys/hwprobe.h> #include <sys/hwprobe.h>
static uint64_t g_hwcap; static uint64_t g_hwcap;
static __riscv_hwprobe_t g_hwprobe_ptr;
static void* g_null;
static riscv_hwprobe g_hwprobes[] = {{.key = RISCV_HWPROBE_KEY_IMA_EXT_0}}; static riscv_hwprobe g_hwprobes[] = {{.key = RISCV_HWPROBE_KEY_IMA_EXT_0}};
extern "C" fn_ptr_t hwcap_resolver(uint64_t hwcap, void* null) { extern "C" fn_ptr_t hwcap_resolver(uint64_t hwcap, __riscv_hwprobe_t hwprobe_ptr, void* null) {
// Check hwcap like arm32/arm64.
g_hwcap = hwcap; g_hwcap = hwcap;
g_hwprobe_ptr = hwprobe_ptr;
// For now, the pointer argument is reserved for future expansion. g_null = null;
if (null != NULL) abort();
// Ensure that __riscv_hwprobe() can be called from an ifunc. // Ensure that __riscv_hwprobe() can be called from an ifunc.
if (__riscv_hwprobe(g_hwprobes, 1, 0, nullptr, 0) != 0) return nullptr; if ((*hwprobe_ptr)(g_hwprobes, 1, 0, nullptr, 0) != 0) return nullptr;
return ret42; return ret42;
} }
@ -102,7 +102,11 @@ TEST(ifunc, hwcap) {
#elif defined(__arm__) #elif defined(__arm__)
EXPECT_EQ(getauxval(AT_HWCAP), g_hwcap); EXPECT_EQ(getauxval(AT_HWCAP), g_hwcap);
#elif defined(__riscv) #elif defined(__riscv)
printf("hwcap=%lx hwprobe_ptr=%p (__riscv_hwprobe=%p) null=%p\n", g_hwcap, g_hwprobe_ptr,
__riscv_hwprobe, g_null);
EXPECT_EQ(getauxval(AT_HWCAP), g_hwcap); EXPECT_EQ(getauxval(AT_HWCAP), g_hwcap);
EXPECT_EQ(nullptr, g_null);
riscv_hwprobe probes[] = {{.key = RISCV_HWPROBE_KEY_IMA_EXT_0}}; riscv_hwprobe probes[] = {{.key = RISCV_HWPROBE_KEY_IMA_EXT_0}};
ASSERT_EQ(0, __riscv_hwprobe(probes, 1, 0, nullptr, 0)); ASSERT_EQ(0, __riscv_hwprobe(probes, 1, 0, nullptr, 0));