diff options
| author | Ravikiran G Thirumalai <kiran@scalex86.org> | 2008-12-31 16:44:46 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-01-02 11:16:29 -0500 |
| commit | 26799a63110dcbe81291ea53178f6b4810d07424 (patch) | |
| tree | 0bdbd0ff3ed50b310d3851f8ab203e7b9c8c4a3c /arch/x86/kernel/head64.c | |
| parent | b58602a4bac012b5f4fc12fe6b46ab237b610d5d (diff) | |
x86: fix incorrect __read_mostly on _boot_cpu_pda
The pda rework (commit 3461b0af025251bbc6b3d56c821c6ac2de6f7209)
to remove static boot cpu pdas introduced a performance bug.
_boot_cpu_pda is the actual pda used by the boot cpu and is definitely
not "__read_mostly" and ended up polluting the read mostly section with
writes. This bug caused regression of about 8-10% on certain syscall
intensive workloads.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Acked-by: Mike Travis <travis@sgi.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/head64.c')
| -rw-r--r-- | arch/x86/kernel/head64.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 388e05a5fc17..b9a4d8c4b935 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c | |||
| @@ -27,7 +27,7 @@ | |||
| 27 | #include <asm/trampoline.h> | 27 | #include <asm/trampoline.h> |
| 28 | 28 | ||
| 29 | /* boot cpu pda */ | 29 | /* boot cpu pda */ |
| 30 | static struct x8664_pda _boot_cpu_pda __read_mostly; | 30 | static struct x8664_pda _boot_cpu_pda; |
| 31 | 31 | ||
| 32 | #ifdef CONFIG_SMP | 32 | #ifdef CONFIG_SMP |
| 33 | /* | 33 | /* |