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Changeset eacb957 in mainline


Ignore:
Timestamp:
2009-12-25T19:38:36Z (12 years ago)
Author:
Jakub Jermar <jakub@…>
Branches:
lfn, master
Children:
bb2dbf8
Parents:
c26eb39 (diff), 245e8399 (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 fix for ticket #149.

Files:
3 edited

Legend:

Unmodified
Added
Removed
  • kernel/arch/sparc64/src/context.S

    rc26eb39 reacb957  
    2828
    2929#include <arch/context_offset.h>
    30 
    31 /**
    32  * Both context_save_arch() and context_restore_arch() are
    33  * leaf-optimized procedures. This kind of optimization
    34  * is very important and prevents any implicit window
    35  * spill/fill/clean traps in these very core kernel
    36  * functions.
    37  */
    38        
    39 #include <arch/context_offset.h>
     30#include <arch/arch.h>
     31#include <arch/regdef.h>
    4032
    4133.text   
     
    4436.global context_restore_arch
    4537
     38/*
     39 * context_save_arch() is required not to create its own stack frame. See the
     40 * generic context.h for explanation.
     41 */
    4642context_save_arch:
     43        #
     44        # Force all our active register windows to memory so that we can find
     45        # them there even if e.g. the thread is migrated to another processor.
     46        #
     47        flushw
     48
    4749        CONTEXT_SAVE_ARCH_CORE %o0
    4850        retl
     
    5153context_restore_arch:
    5254        #
    53         # Flush all active windows.
    54         # This is essential, because CONTEXT_LOAD overwrites
    55         # %sp of CWP - 1 with the value written to %fp of CWP.
    56         # Flushing all active windows mitigates this problem
    57         # as CWP - 1 becomes the overlap window.
     55        # Forget all previous windows, they are not going to be needed again.
     56        # Enforce a window fill on the next RESTORE instruction by setting
     57        # CANRESTORE to zero and other window configuration registers
     58        # accordingly. Note that the same can be achieved by executing the
     59        # FLUSHW instruction, but since we don't need to remember the previous
     60        # windows, we do the former and save thus some unnecessary window
     61        # spills.
    5862        #
    59         flushw
    60        
     63        rdpr %pstate, %l0
     64        andn %l0, PSTATE_IE_BIT, %l1
     65        wrpr %l1, %pstate
     66        wrpr %g0, 0, %canrestore
     67        wrpr %g0, 0, %otherwin
     68        wrpr %g0, NWINDOWS - 2, %cansave
     69        wrpr %l0, %pstate
     70
    6171        CONTEXT_RESTORE_ARCH_CORE %o0
    6272        retl
  • kernel/arch/sparc64/src/trap/trap_table.S

    rc26eb39 reacb957  
    652652         * spilled to kernel memory (i.e. register window buffer). Moreover,
    653653         * if the scheduler was called in the meantime, all valid windows
    654          * belonging to other threads were spilled by context_restore().
     654         * belonging to other threads were spilled by context_save().
    655655         * If OTHERWIN is non-zero, then some userspace windows are still
    656656         * valid. Others might have been spilled. However, the CWP pointer
  • uspace/lib/libc/arch/sparc64/src/fibril.S

    rc26eb39 reacb957  
    3535
    3636context_save:
     37        #
     38        # We rely on the kernel to flush our active register windows to memory
     39        # should a thread switch occur.
     40        #
    3741        CONTEXT_SAVE_ARCH_CORE %o0
    3842        retl
     
    4246        #
    4347        # Flush all active windows.
    44         # This is essential, because CONTEXT_LOAD overwrites
    45         # %sp of CWP - 1 with the value written to %fp of CWP.
    46         # Flushing all active windows mitigates this problem
    47         # as CWP - 1 becomes the overlap window.
    48         #               
     48        # This is essential, because CONTEXT_RESTORE_ARCH_CORE overwrites %sp of
     49        # CWP - 1 with the value written to %fp of CWP.  Flushing all active
     50        # windows mitigates this problem as CWP - 1 becomes the overlap window.
     51        #
    4952        flushw
    5053       
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