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authorTrond Myklebust <trond.myklebust@primarydata.com>2016-03-16 23:24:36 +0300
committerTrond Myklebust <trond.myklebust@primarydata.com>2016-03-16 23:25:09 +0300
commit1425075e7272faaa3629a1e2df679c0ba4cf55d3 (patch)
tree6d79a735f8a02d6dc9e27b915f6244fe1ab6b7ff /arch/x86/lib/copy_user_64.S
parent849dc3244c916545790bfb9055625a3719061c92 (diff)
parent2fa8f88d8892507ecff0126fbc67906740491d31 (diff)
downloadlinux-1425075e7272faaa3629a1e2df679c0ba4cf55d3.tar.xz
Merge tag 'nfs-rdma-4.6-1' of git://git.linux-nfs.org/projects/anna/nfs-rdma
NFS: NFSoRDMA Client Side Changes These patches include several bugfixes and cleanups for the NFSoRDMA client. This includes bugfixes for NFS v4.1, proper RDMA_ERROR handling, and fixes from the recent workqueue swicchover. These patches also switch xprtrdma to use the new CQ API Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> * tag 'nfs-rdma-4.6-1' of git://git.linux-nfs.org/projects/anna/nfs-rdma: (787 commits) xprtrdma: Use new CQ API for RPC-over-RDMA client send CQs xprtrdma: Use an anonymous union in struct rpcrdma_mw xprtrdma: Use new CQ API for RPC-over-RDMA client receive CQs xprtrdma: Serialize credit accounting again xprtrdma: Properly handle RDMA_ERROR replies rpcrdma: Add RPCRDMA_HDRLEN_ERR xprtrdma: Do not wait if ib_post_send() fails xprtrdma: Segment head and tail XDR buffers on page boundaries xprtrdma: Clean up dprintk format string containing a newline xprtrdma: Clean up physical_op_map() xprtrdma: Clean up unused RPCRDMA_INLINE_PAD_THRESH macro
Diffstat (limited to 'arch/x86/lib/copy_user_64.S')
-rw-r--r--arch/x86/lib/copy_user_64.S142
1 files changed, 101 insertions, 41 deletions
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index 982ce34f4a9b..27f89c79a44b 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -232,17 +232,31 @@ ENDPROC(copy_user_enhanced_fast_string)
/*
* copy_user_nocache - Uncached memory copy with exception handling
- * This will force destination/source out of cache for more performance.
+ * This will force destination out of cache for more performance.
+ *
+ * Note: Cached memory copy is used when destination or size is not
+ * naturally aligned. That is:
+ * - Require 8-byte alignment when size is 8 bytes or larger.
+ * - Require 4-byte alignment when size is 4 bytes.
*/
ENTRY(__copy_user_nocache)
ASM_STAC
+
+ /* If size is less than 8 bytes, go to 4-byte copy */
cmpl $8,%edx
- jb 20f /* less then 8 bytes, go to byte copy loop */
+ jb .L_4b_nocache_copy_entry
+
+ /* If destination is not 8-byte aligned, "cache" copy to align it */
ALIGN_DESTINATION
+
+ /* Set 4x8-byte copy count and remainder */
movl %edx,%ecx
andl $63,%edx
shrl $6,%ecx
- jz 17f
+ jz .L_8b_nocache_copy_entry /* jump if count is 0 */
+
+ /* Perform 4x8-byte nocache loop-copy */
+.L_4x8b_nocache_copy_loop:
1: movq (%rsi),%r8
2: movq 1*8(%rsi),%r9
3: movq 2*8(%rsi),%r10
@@ -262,60 +276,106 @@ ENTRY(__copy_user_nocache)
leaq 64(%rsi),%rsi
leaq 64(%rdi),%rdi
decl %ecx
- jnz 1b
-17: movl %edx,%ecx
+ jnz .L_4x8b_nocache_copy_loop
+
+ /* Set 8-byte copy count and remainder */
+.L_8b_nocache_copy_entry:
+ movl %edx,%ecx
andl $7,%edx
shrl $3,%ecx
- jz 20f
-18: movq (%rsi),%r8
-19: movnti %r8,(%rdi)
+ jz .L_4b_nocache_copy_entry /* jump if count is 0 */
+
+ /* Perform 8-byte nocache loop-copy */
+.L_8b_nocache_copy_loop:
+20: movq (%rsi),%r8
+21: movnti %r8,(%rdi)
leaq 8(%rsi),%rsi
leaq 8(%rdi),%rdi
decl %ecx
- jnz 18b
-20: andl %edx,%edx
- jz 23f
+ jnz .L_8b_nocache_copy_loop
+
+ /* If no byte left, we're done */
+.L_4b_nocache_copy_entry:
+ andl %edx,%edx
+ jz .L_finish_copy
+
+ /* If destination is not 4-byte aligned, go to byte copy: */
+ movl %edi,%ecx
+ andl $3,%ecx
+ jnz .L_1b_cache_copy_entry
+
+ /* Set 4-byte copy count (1 or 0) and remainder */
movl %edx,%ecx
-21: movb (%rsi),%al
-22: movb %al,(%rdi)
+ andl $3,%edx
+ shrl $2,%ecx
+ jz .L_1b_cache_copy_entry /* jump if count is 0 */
+
+ /* Perform 4-byte nocache copy: */
+30: movl (%rsi),%r8d
+31: movnti %r8d,(%rdi)
+ leaq 4(%rsi),%rsi
+ leaq 4(%rdi),%rdi
+
+ /* If no bytes left, we're done: */
+ andl %edx,%edx
+ jz .L_finish_copy
+
+ /* Perform byte "cache" loop-copy for the remainder */
+.L_1b_cache_copy_entry:
+ movl %edx,%ecx
+.L_1b_cache_copy_loop:
+40: movb (%rsi),%al
+41: movb %al,(%rdi)
incq %rsi
incq %rdi
decl %ecx
- jnz 21b
-23: xorl %eax,%eax
+ jnz .L_1b_cache_copy_loop
+
+ /* Finished copying; fence the prior stores */
+.L_finish_copy:
+ xorl %eax,%eax
ASM_CLAC
sfence
ret
.section .fixup,"ax"
-30: shll $6,%ecx
+.L_fixup_4x8b_copy:
+ shll $6,%ecx
addl %ecx,%edx
- jmp 60f
-40: lea (%rdx,%rcx,8),%rdx
- jmp 60f
-50: movl %ecx,%edx
-60: sfence
+ jmp .L_fixup_handle_tail
+.L_fixup_8b_copy:
+ lea (%rdx,%rcx,8),%rdx
+ jmp .L_fixup_handle_tail
+.L_fixup_4b_copy:
+ lea (%rdx,%rcx,4),%rdx
+ jmp .L_fixup_handle_tail
+.L_fixup_1b_copy:
+ movl %ecx,%edx
+.L_fixup_handle_tail:
+ sfence
jmp copy_user_handle_tail
.previous
- _ASM_EXTABLE(1b,30b)
- _ASM_EXTABLE(2b,30b)
- _ASM_EXTABLE(3b,30b)
- _ASM_EXTABLE(4b,30b)
- _ASM_EXTABLE(5b,30b)
- _ASM_EXTABLE(6b,30b)
- _ASM_EXTABLE(7b,30b)
- _ASM_EXTABLE(8b,30b)
- _ASM_EXTABLE(9b,30b)
- _ASM_EXTABLE(10b,30b)
- _ASM_EXTABLE(11b,30b)
- _ASM_EXTABLE(12b,30b)
- _ASM_EXTABLE(13b,30b)
- _ASM_EXTABLE(14b,30b)
- _ASM_EXTABLE(15b,30b)
- _ASM_EXTABLE(16b,30b)
- _ASM_EXTABLE(18b,40b)
- _ASM_EXTABLE(19b,40b)
- _ASM_EXTABLE(21b,50b)
- _ASM_EXTABLE(22b,50b)
+ _ASM_EXTABLE(1b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(2b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(3b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(4b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(5b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(6b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(7b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(8b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(9b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(10b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(11b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(12b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(13b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(14b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(15b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(16b,.L_fixup_4x8b_copy)
+ _ASM_EXTABLE(20b,.L_fixup_8b_copy)
+ _ASM_EXTABLE(21b,.L_fixup_8b_copy)
+ _ASM_EXTABLE(30b,.L_fixup_4b_copy)
+ _ASM_EXTABLE(31b,.L_fixup_4b_copy)
+ _ASM_EXTABLE(40b,.L_fixup_1b_copy)
+ _ASM_EXTABLE(41b,.L_fixup_1b_copy)
ENDPROC(__copy_user_nocache)