unify static and dynamic linked implementations of thread-local storage

[musl] / src / env / __init_tls.c

diff --git a/src/env/__init_tls.c b/src/env/__init_tls.c
index 73551e6..0107a54 100644 (file)
--- a/src/env/__init_tls.c
+++ b/src/env/__init_tls.c
@@ -8,9 +8,6 @@
 #include "atomic.h"
 #include "syscall.h"
 
-#ifndef SHARED
-static
-#endif
 int __init_tp(void *p)
 {
        pthread_t td = p;
@@ -24,8 +21,6 @@ int __init_tp(void *p)
        return 0;
 }
 
-#ifndef SHARED
-
 static struct builtin_tls {
        char c;
        struct pthread pt;
@@ -33,33 +28,40 @@ static struct builtin_tls {
 } builtin_tls[1];
 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
 
-struct tls_image {
-       void *image;
-       size_t len, size, align;
-} __static_tls;
-
-#define T __static_tls
+static struct tls_module main_tls;
 
 void *__copy_tls(unsigned char *mem)
 {
        pthread_t td;
-       if (!T.image) return mem;
-       void **dtv = (void *)mem;
-       dtv[0] = (void *)1;
+       struct tls_module *p;
+       size_t i;
+       void **dtv;
+
 #ifdef TLS_ABOVE_TP
-       mem += sizeof(void *) * 2;
-       mem += -((uintptr_t)mem + sizeof(struct pthread)) & (T.align-1);
+       dtv = (void **)(mem + libc.tls_size) - (libc.tls_cnt + 1);
+
+       mem += -((uintptr_t)mem + sizeof(struct pthread)) & (libc.tls_align-1);
        td = (pthread_t)mem;
        mem += sizeof(struct pthread);
+
+       for (i=1, p=libc.tls_head; p; i++, p=p->next) {
+               dtv[i] = mem + p->offset;
+               memcpy(dtv[i], p->image, p->len);
+       }
 #else
+       dtv = (void **)mem;
+
        mem += libc.tls_size - sizeof(struct pthread);
-       mem -= (uintptr_t)mem & (T.align-1);
+       mem -= (uintptr_t)mem & (libc.tls_align-1);
        td = (pthread_t)mem;
-       mem -= T.size;
+
+       for (i=1, p=libc.tls_head; p; i++, p=p->next) {
+               dtv[i] = mem - p->offset;
+               memcpy(dtv[i], p->image, p->len);
+       }
 #endif
+       dtv[0] = (void *)libc.tls_cnt;
        td->dtv = td->dtv_copy = dtv;
-       dtv[1] = mem;
-       memcpy(mem, T.image, T.len);
        return td;
 }
 
@@ -69,7 +71,7 @@ typedef Elf32_Phdr Phdr;
 typedef Elf64_Phdr Phdr;
 #endif
 
-void __init_tls(size_t *aux)
+static void static_init_tls(size_t *aux)
 {
        unsigned char *p;
        size_t n;
@@ -86,16 +88,24 @@ void __init_tls(size_t *aux)
        }
 
        if (tls_phdr) {
-               T.image = (void *)(base + tls_phdr->p_vaddr);
-               T.len = tls_phdr->p_filesz;
-               T.size = tls_phdr->p_memsz;
-               T.align = tls_phdr->p_align;
+               main_tls.image = (void *)(base + tls_phdr->p_vaddr);
+               main_tls.len = tls_phdr->p_filesz;
+               main_tls.size = tls_phdr->p_memsz;
+               main_tls.align = tls_phdr->p_align;
+               libc.tls_cnt = 1;
+               libc.tls_head = &main_tls;
        }
 
-       T.size += (-T.size - (uintptr_t)T.image) & (T.align-1);
-       if (T.align < MIN_TLS_ALIGN) T.align = MIN_TLS_ALIGN;
+       main_tls.size += (-main_tls.size - (uintptr_t)main_tls.image)
+               & (main_tls.align-1);
+       if (main_tls.align < MIN_TLS_ALIGN) main_tls.align = MIN_TLS_ALIGN;
+#ifndef TLS_ABOVE_TP
+       main_tls.offset = main_tls.size;
+#endif
 
-       libc.tls_size = 2*sizeof(void *)+T.size+T.align+sizeof(struct pthread)
+       libc.tls_align = main_tls.align;
+       libc.tls_size = 2*sizeof(void *) + sizeof(struct pthread)
+               + main_tls.size + main_tls.align
                + MIN_TLS_ALIGN-1 & -MIN_TLS_ALIGN;
 
        if (libc.tls_size > sizeof builtin_tls) {
@@ -117,6 +127,5 @@ void __init_tls(size_t *aux)
        if (__init_tp(__copy_tls(mem)) < 0)
                a_crash();
 }
-#else
-void __init_tls(size_t *auxv) { }
-#endif
+
+weak_alias(static_init_tls, __init_tls);