From 6bb2d37af6772cada51b0871d3184f7783779364 Mon Sep 17 00:00:00 2001
From: Waldemar Brodkorb <wbx@openadk.org>
Date: Wed, 20 Mar 2024 09:44:40 +0100
Subject: riscv32: sync with riscv64
---
libpthread/nptl/sysdeps/riscv32/tls.h | 117 +++++++++++++---------------------
1 file changed, 43 insertions(+), 74 deletions(-)
(limited to 'libpthread/nptl/sysdeps/riscv32/tls.h')
diff --git a/libpthread/nptl/sysdeps/riscv32/tls.h b/libpthread/nptl/sysdeps/riscv32/tls.h
index ed6df8186..8ef9f3511 100644
--- a/libpthread/nptl/sysdeps/riscv32/tls.h
+++ b/libpthread/nptl/sysdeps/riscv32/tls.h
@@ -1,6 +1,5 @@
/* Definition for thread-local data handling. NPTL/RISCV32 version.
Copyright (C) 2005, 2007, 2011 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@@ -35,15 +34,6 @@ typedef union dtv
} pointer;
} dtv_t;
-typedef struct
-{
- dtv_t *dtv;
-} tcbhead_t;
-
-register tcbhead_t *__thread_self __asm__("tp");
-
-# define TLS_MULTIPLE_THREADS_IN_TCB 1
-
#else /* __ASSEMBLER__ */
# include <tcb-offsets.h>
#endif /* __ASSEMBLER__ */
@@ -58,71 +48,56 @@ register tcbhead_t *__thread_self __asm__("tp");
#ifndef __ASSEMBLER__
+register void *__thread_self __asm__("tp");
+# define READ_THREAD_POINTER() ({ __thread_self; })
+
/* Get system call information. */
# include <sysdep.h>
-/* The TP points to the start of the TLS block.
- * As I understand it, this isn't strictly that "TP points to DTV" - it's
- * more where to place the TCB in the TLS block. This will place it in
- * the beginning.
- *
- * Layout:
- * ------------------------------------
- * | PRE | TCB | TLS MEMORY .. |
- * ------------------------------------
- * ^ x4 / TP
- *
- * PRE is the struct pthread described below
- * TCB is tcbhead_t
- * TLS memory is where the TLS program sections are loaded
- *
- * See _dl_allocate_tls_storage and __libc_setup_tls for more information.
- */
+/* The TP points to the start of the TLS block. */
# define TLS_DTV_AT_TP 1
/* Get the thread descriptor definition. */
# include <../../descr.h>
-/* Requirements for the TCB. */
-# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
+typedef struct
+{
+ dtv_t *dtv;
+ void *private;
+} tcbhead_t;
-# define TLS_TCB_SIZE sizeof (tcbhead_t)
-# define TLS_TCB_ALIGN __alignof__ (tcbhead_t)
+/* This is the size of the initial TCB. Because our TCB is before the thread
+ pointer, we don't need this. */
+# define TLS_INIT_TCB_SIZE 0
+# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-/* This is the size of the TCB. */
+/* This is the size of the TCB. Because our TCB is before the thread
+ pointer, we don't need this. */
+# define TLS_TCB_SIZE 0
+# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-/* This is the size we need before TCB.
- * To support THREAD_GETMEM with friends we want to have a
- * struct pthread available.
- * Yank it in infront of everything, I'm sure nobody will mind.
- *
- * This memory is really allocated PRE the TLS block, so it's possible
- * to do ((char*)tlsblock) - TLS_PRE_TCB_SIZE to access it.
- * This is done for THREAD_SELF. */
-# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
+/* This is the size we need before TCB - actually, it includes the TCB. */
+# define TLS_PRE_TCB_SIZE \
+ (sizeof (struct pthread) \
+ + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
+ & ~(__alignof (struct pthread) - 1)))
+/* The thread pointer tp points to the end of the TCB.
+ The pthread_descr structure is immediately in front of the TCB. */
+# define TLS_TCB_OFFSET 0
-/* Install the dtv pointer.
- * When called, dtvp is a pointer not the DTV per say (which should start
- * with the generation counter) but to the length of the DTV.
- * We can always index with -1, so we store dtvp[1]
- */
+/* Install the dtv pointer. The pointer passed is to the element with
+ index -1 which contain the length. */
# define INSTALL_DTV(tcbp, dtvp) \
- (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1)
+ (((tcbhead_t *) (tcbp))[-1].dtv = (dtvp) + 1)
-/* Install new dtv for current thread
- * In a logicial world dtv here would also point to the length of the DTV.
- * However it does not, this time it points to the generation counter,
- * so just store it.
- *
- * Note: -1 is still valid and contains the length. */
+/* Install new dtv for current thread */
# define INSTALL_NEW_DTV(dtv) \
(THREAD_DTV() = (dtv))
/* Return dtv of given thread descriptor. */
# define GET_DTV(tcbp) \
- (((tcbhead_t *) (tcbp))->dtv)
+ (((tcbhead_t *) (tcbp))[-1].dtv)
/* Code to initially initialize the thread pointer.
*
@@ -136,31 +111,21 @@ register tcbhead_t *__thread_self __asm__("tp");
* It's hard to fail this, so return NULL always.
*/
# define TLS_INIT_TP(tcbp, secondcall) \
- ({__thread_self = ((tcbhead_t *)tcbp + 1); NULL;})
+ ({ __thread_self = (char*)tcbp + TLS_TCB_OFFSET; NULL; })
-/* Return the address of the dtv for the current thread.
- *
- * Dereference TP, offset to dtv - really straightforward.
- * Remember that we made TP point to after tcb, so we need to reverse that.
- */
+/* Return the address of the dtv for the current thread. */
# define THREAD_DTV() \
- ((((tcbhead_t *)__thread_self)-1)->dtv)
+ (((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))[-1].dtv)
-/* Return the thread descriptor for the current thread.
- *
- * Return a pointer to the TLS_PRE area where we allocated space for
- * a struct pthread. Again, TP points to after tcbhead_t, compensate with
- * TLS_INIT_TCB_SIZE.
- *
- * I regard this is a seperate system from the "normal" TLS.
- */
+/* Return the thread descriptor for the current thread. */
# define THREAD_SELF \
- ((struct pthread *) ((char *) __thread_self - TLS_INIT_TCB_SIZE \
- - TLS_PRE_TCB_SIZE))
+ ((struct pthread *) (READ_THREAD_POINTER () \
+ - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE))
-/* Magic for libthread_db to know how to do THREAD_SELF. */
+/* Informs libthread_db that the thread pointer is register 4, which is used
+ * to know how to do THREAD_SELF. */
# define DB_THREAD_SELF \
- CONST_THREAD_AREA (64, sizeof (struct pthread))
+ REGISTER (64, 64, 4 * 8, - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
/* Access to data in the thread descriptor is easy. */
#define THREAD_GETMEM(descr, member) \
@@ -172,6 +137,10 @@ register tcbhead_t *__thread_self __asm__("tp");
#define THREAD_SETMEM_NC(descr, member, idx, value) \
descr->member[idx] = (value)
+/* l_tls_offset == 0 is perfectly valid, so we have to use some different
+ value to mean unset l_tls_offset. */
+# define NO_TLS_OFFSET -1
+
/* Get and set the global scope generation counter in struct pthread. */
#define THREAD_GSCOPE_FLAG_UNUSED 0
#define THREAD_GSCOPE_FLAG_USED 1
--
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