Changeset f33eab7 for libcfa

Timestamp:

Nov 10, 2020, 2:45:16 PM (4 years ago)

Author:

m3zulfiq <m3zulfiq@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

1d379b5

Parents:

685810e (diff), b82d140 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' of plg.uwaterloo.ca:software/cfa/cfa-cc

Location:

libcfa/src/concurrency

Files:

• kernel/fwd.hfa (modified) (1 diff)
• preemption.cfa (modified) (8 diffs)

libcfa/src/concurrency/kernel/fwd.hfa

@@ -65 +65 @@
 
                 extern uintptr_t __cfatls_get( unsigned long int member );
-                // #define publicTLS_get( member ) ((typeof(__cfaabi_tls.member))__cfatls_get( __builtin_offsetof(KernelThreadData, member) ))
-                #define publicTLS_get( member ) (__cfaabi_tls.member)
-                // extern forall(otype T) T __cfatls_get( T * member, T value );
-                // #define publicTLS_set( member, value ) __cfatls_set( (typeof(member)*)__builtin_offsetof(KernelThreadData, member), value );
+                #define publicTLS_get( member ) ((typeof(__cfaabi_tls.member))__cfatls_get( __builtin_offsetof(KernelThreadData, member) ))
 
                 static inline uint64_t __tls_rand() {

libcfa/src/concurrency/preemption.cfa

@@ -231 +231 @@
 }
 
+struct asm_region {
+        void * before;
+        void * after;
+};
+
+static inline bool __cfaasm_in( void * ip, struct asm_region & region ) {
+        return ip >= region.before && ip <= region.after;
+}
+
+
 //----------
 // Get data from the TLS block
+// struct asm_region __cfaasm_get;
 uintptr_t __cfatls_get( unsigned long int offset ) __attribute__((__noinline__)); //no inline to avoid problems
 uintptr_t __cfatls_get( unsigned long int offset ) {
+        // __cfaasm_get.before = ({ void * value; asm("movq $__cfaasm_get_before, %[v]\n\t" : [v]"=r"(value) ); value; });
+        // __cfaasm_get.after  = ({ void * value; asm("movq $__cfaasm_get_after , %[v]\n\t" : [v]"=r"(value) ); value; });
         // create a assembler label before
         // marked as clobber all to avoid movement
@@ -253 +266 @@
                 // create a assembler label before
                 // marked as clobber all to avoid movement
-                asm volatile("__cfaasm_disable_before:":::"memory");
+                asm volatile("__cfaasm_dsable_before:":::"memory");
 
                 with( __cfaabi_tls.preemption_state ) {
@@ -275 +288 @@
                 // create a assembler label after
                 // marked as clobber all to avoid movement
-                asm volatile("__cfaasm_disable_after:":::"memory");
+                asm volatile("__cfaasm_dsable_after:":::"memory");
         }
 
@@ -283 +296 @@
                 // create a assembler label before
                 // marked as clobber all to avoid movement
-                asm volatile("__cfaasm_enable_before:":::"memory");
+                asm volatile("__cfaasm_enble_before:":::"memory");
 
                 processor   * proc = __cfaabi_tls.this_processor; // Cache the processor now since interrupts can start happening after the atomic store
@@ -318 +331 @@
                 // create a assembler label after
                 // marked as clobber all to avoid movement
-                asm volatile("__cfaasm_enable_after:":::"memory");
+                asm volatile("__cfaasm_enble_after:":::"memory");
         }
 
@@ -386 +399 @@
 }
 
+//-----------------------------------------------------------------------------
+// Some assembly required
+#if defined( __i386 )
+        #ifdef __PIC__
+                #define RELOC_PRELUDE( label ) \
+                        "calll   .Lcfaasm_prelude_" #label "$pb\n\t" \
+                        ".Lcfaasm_prelude_" #label "$pb:\n\t" \
+                        "popl    %%eax\n\t" \
+                        ".Lcfaasm_prelude_" #label "_end:\n\t" \
+                        "addl    $_GLOBAL_OFFSET_TABLE_+(.Lcfaasm_prelude_" #label "_end-.Lcfaasm_prelude_" #label "$pb), %%eax\n\t"
+                #define RELOC_PREFIX ""
+                #define RELOC_SUFFIX "@GOT(%%eax)"
+        #else
+                #define RELOC_PREFIX "$"
+                #define RELOC_SUFFIX ""
+        #endif
+        #define __cfaasm_label( label ) static struct asm_region label = \
+                ({ \
+                        struct asm_region region; \
+                        asm( \
+                                RELOC_PRELUDE( label ) \
+                                "movl " RELOC_PREFIX "__cfaasm_" #label "_before" RELOC_SUFFIX ", %[vb]\n\t" \
+                                "movl " RELOC_PREFIX "__cfaasm_" #label "_after"  RELOC_SUFFIX ", %[va]\n\t" \
+                                 : [vb]"=r"(region.before), [va]"=r"(region.after) \
+                        ); \
+                        region; \
+                });
+#elif defined( __x86_64 )
+        #ifdef __PIC__
+                #define RELOC_PREFIX ""
+                #define RELOC_SUFFIX "@GOTPCREL(%%rip)"
+        #else
+                #define RELOC_PREFIX "$"
+                #define RELOC_SUFFIX ""
+        #endif
+        #define __cfaasm_label( label ) static struct asm_region label = \
+                ({ \
+                        struct asm_region region; \
+                        asm( \
+                                "movq " RELOC_PREFIX "__cfaasm_" #label "_before" RELOC_SUFFIX ", %[vb]\n\t" \
+                                "movq " RELOC_PREFIX "__cfaasm_" #label "_after"  RELOC_SUFFIX ", %[va]\n\t" \
+                                 : [vb]"=r"(region.before), [va]"=r"(region.after) \
+                        ); \
+                        region; \
+                });
+#elif defined( __aarch64__ )
+        #ifdef __PIC__
+                #define RELOC_TAG "@PLT"
+        #else
+                #define RELOC_TAG ""
+        #endif
+        #define __cfaasm_label( label ) \
+                ({ \
+                        struct asm_region region; \
+                        asm( \
+                                "mov %[vb], __cfaasm_" #label "_before@GOTPCREL(%%rip)"  "\n\t" \
+                                "mov %[va], __cfaasm_" #label "_after@GOTPCREL(%%rip)"   "\n\t" \
+                                 : [vb]"=r"(region.before), [va]"=r"(region.after) \
+                        ); \
+                        region; \
+                });
+#else
+        #error unknown hardware architecture
+#endif
+
 // KERNEL ONLY
 // Check if a __cfactx_switch signal handler shoud defer
 // If true  : preemption is safe
 // If false : preemption is unsafe and marked as pending
-static inline bool preemption_ready() {
+static inline bool preemption_ready( void * ip ) {
+        // Get all the region for which it is not safe to preempt
+        __cfaasm_label( get    );
+        __cfaasm_label( check  );
+        __cfaasm_label( dsable );
+        __cfaasm_label( enble );
+        __cfaasm_label( nopoll );
+
         // Check if preemption is safe
-        bool ready = __cfaabi_tls.preemption_state.enabled && ! __cfaabi_tls.preemption_state.in_progress;
-
+        bool ready = true;
+        if( __cfaasm_in( ip, get    ) ) { ready = false; goto EXIT; };
+        if( __cfaasm_in( ip, check  ) ) { ready = false; goto EXIT; };
+        if( __cfaasm_in( ip, dsable ) ) { ready = false; goto EXIT; };
+        if( __cfaasm_in( ip, enble  ) ) { ready = false; goto EXIT; };
+        if( __cfaasm_in( ip, nopoll ) ) { ready = false; goto EXIT; };
+        if( !__cfaabi_tls.preemption_state.enabled) { ready = false; goto EXIT; };
+        if( __cfaabi_tls.preemption_state.in_progress ) { ready = false; goto EXIT; };
+
+EXIT:
         // Adjust the pending flag accordingly
         __cfaabi_tls.this_processor->pending_preemption = !ready;
@@ -468 +561 @@
 // Kernel Signal Handlers
 //=============================================================================================
-struct asm_region {
-        void * before;
-        void * after;
-};
-
-//-----------------------------------------------------------------------------
-// Some assembly required
-#if defined( __i386 )
-        #define __cfaasm_label( label ) \
-                ({ \
-                        struct asm_region region; \
-                        asm( \
-                                "movl $__cfaasm_" #label "_before, %[vb]\n\t" \
-                                "movl $__cfaasm_" #label "_after , %[va]\n\t" \
-                                 : [vb]"=r"(region.before), [vb]"=r"(region.before) \
-                        ); \
-                        region; \
-                });
-#elif defined( __x86_64 )
-        #ifdef __PIC__
-                #define PLT "@PLT"
-        #else
-                #define PLT ""
-        #endif
-        #define __cfaasm_label( label ) \
-                ({ \
-                        struct asm_region region; \
-                        asm( \
-                                "movq $__cfaasm_" #label "_before" PLT ", %[vb]\n\t" \
-                                "movq $__cfaasm_" #label "_after"  PLT ", %[va]\n\t" \
-                                 : [vb]"=r"(region.before), [va]"=r"(region.after) \
-                        ); \
-                        region; \
-                });
-#elif defined( __aarch64__ )
-        #error __cfaasm_label undefined for arm
-#else
-        #error unknown hardware architecture
-#endif
-
 __cfaabi_dbg_debug_do( static thread_local void * last_interrupt = 0; )
 
@@ -530 +583 @@
 
         // Check if it is safe to preempt here
-        if( !preemption_ready() ) { return; }
-
-        struct asm_region region;
-        region = __cfaasm_label( get     ); if( ip >= region.before && ip <= region.after ) return;
-        region = __cfaasm_label( check   ); if( ip >= region.before && ip <= region.after ) return;
-        region = __cfaasm_label( disable ); if( ip >= region.before && ip <= region.after ) return;
-        region = __cfaasm_label( enable  ); if( ip >= region.before && ip <= region.after ) return;
-        region = __cfaasm_label( nopoll  ); if( ip >= region.before && ip <= region.after ) return;
+        if( !preemption_ready( ip ) ) { return; }
 
         __cfaabi_dbg_print_buffer_decl( " KERNEL: preempting core %p (%p @ %p).\n", __cfaabi_tls.this_processor, __cfaabi_tls.this_thread, (void *)(cxt->uc_mcontext.CFA_REG_IP) );