From: Toshi Kani <toshi.kani@hp.com>
To: hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com,
akpm@linux-foundation.org, arnd@arndb.de
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, x86@kernel.org,
linux-nvdimm@lists.01.org, jgross@suse.com,
stefan.bader@canonical.com, luto@amacapital.net, hmh@hmh.eng.br,
yigal@plexistor.com, konrad.wilk@oracle.com, Elliott@hp.com,
mcgrof@suse.com, hch@lst.de, Toshi Kani <toshi.kani@hp.com>
Subject: [PATCH v10 10/12] x86, mm, pat: Cleanup init flags in pat_init()
Date: Wed, 27 May 2015 09:19:02 -0600 [thread overview]
Message-ID: <1432739944-22633-11-git-send-email-toshi.kani@hp.com> (raw)
In-Reply-To: <1432739944-22633-1-git-send-email-toshi.kani@hp.com>
pat_init() uses two flags, 'boot_cpu' and 'boot_pat_state', for
tracking the boot CPU's initialization status. 'boot_pat_state'
is also overloaded to carry the boot PAT value.
This patch cleans this up by replacing them with a new single
flag, 'boot_cpu_done', to track the boot CPU's initialization
status. 'boot_pat_state' is only used to carry the boot PAT
value as a result.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
---
arch/x86/mm/pat.c | 42 ++++++++++++++++++++----------------------
1 file changed, 20 insertions(+), 22 deletions(-)
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 92fc635..7cfd995 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -201,26 +201,31 @@ void pat_init_cache_modes(void)
void pat_init(void)
{
u64 pat;
- bool boot_cpu = !boot_pat_state;
struct cpuinfo_x86 *c = &boot_cpu_data;
+ static bool boot_cpu_done;
if (!pat_enabled)
return;
- if (!cpu_has_pat) {
- if (!boot_pat_state) {
+ if (!boot_cpu_done) {
+ if (!cpu_has_pat) {
pat_disable("PAT not supported by CPU.");
return;
- } else {
- /*
- * If this happens we are on a secondary CPU, but
- * switched to PAT on the boot CPU. We have no way to
- * undo PAT.
- */
- printk(KERN_ERR "PAT enabled, "
- "but not supported by secondary CPU\n");
- BUG();
}
+
+ rdmsrl(MSR_IA32_CR_PAT, boot_pat_state);
+ if (!boot_pat_state) {
+ pat_disable("PAT read returns always zero, disabled.");
+ return;
+ }
+ } else if (!cpu_has_pat) {
+ /*
+ * If this happens we are on a secondary CPU, but
+ * switched to PAT on the boot CPU. We have no way to
+ * undo PAT.
+ */
+ pr_err("PAT enabled, but not supported by secondary CPU\n");
+ BUG();
}
if ((c->x86_vendor == X86_VENDOR_INTEL) &&
@@ -279,19 +284,12 @@ void pat_init(void)
PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, WT);
}
- /* Boot CPU check */
- if (!boot_pat_state) {
- rdmsrl(MSR_IA32_CR_PAT, boot_pat_state);
- if (!boot_pat_state) {
- pat_disable("PAT read returns always zero, disabled.");
- return;
- }
- }
-
wrmsrl(MSR_IA32_CR_PAT, pat);
- if (boot_cpu)
+ if (!boot_cpu_done) {
pat_init_cache_modes();
+ boot_cpu_done = true;
+ }
}
#undef PAT
--
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next prev parent reply other threads:[~2015-05-27 15:39 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-27 15:18 [PATCH v10 0/12] Support Write-Through mapping on x86 Toshi Kani
2015-05-27 15:18 ` [PATCH v10 1/12] x86, mm, pat: Set WT to PA7 slot of PAT MSR Toshi Kani
2015-05-27 15:18 ` [PATCH v10 2/12] x86, mm, pat: Change reserve_memtype() for WT Toshi Kani
2015-05-27 15:18 ` [PATCH v10 3/12] x86, asm: Change is_new_memtype_allowed() " Toshi Kani
2015-05-27 15:18 ` [PATCH v10 4/12] x86, mm, asm-gen: Add ioremap_wt() " Toshi Kani
2015-05-27 15:18 ` [PATCH v10 5/12] arch/*/asm/io.h: Add ioremap_wt() to all architectures Toshi Kani
2015-05-27 15:18 ` [PATCH v10 6/12] video/fbdev, asm/io.h: Remove ioremap_writethrough() Toshi Kani
2015-05-27 15:18 ` [PATCH v10 7/12] x86, mm, pat: Add pgprot_writethrough() for WT Toshi Kani
2015-05-27 15:19 ` [PATCH v10 8/12] x86, mm, asm: Add WT support to set_page_memtype() Toshi Kani
2015-05-27 15:19 ` [PATCH v10 9/12] x86, mm: Add set_memory_wt() for WT Toshi Kani
2015-05-27 15:19 ` Toshi Kani [this message]
2015-05-29 8:59 ` [PATCH v10 10/12] x86, mm, pat: Cleanup init flags in pat_init() Borislav Petkov
2015-05-27 15:19 ` [PATCH v10 11/12] x86, mm, pat: Refactor !pat_enabled handling Toshi Kani
2015-05-29 8:58 ` Borislav Petkov
2015-05-29 14:27 ` Toshi Kani
2015-05-29 15:13 ` Borislav Petkov
2015-05-29 15:17 ` Toshi Kani
2015-05-27 15:19 ` [PATCH v10 12/12] drivers/block/pmem: Map NVDIMM with ioremap_wt() Toshi Kani
2015-05-29 9:11 ` Borislav Petkov
2015-05-29 14:43 ` Dan Williams
2015-05-29 15:03 ` Toshi Kani
2015-05-29 18:19 ` Dan Williams
2015-05-29 18:32 ` Toshi Kani
2015-05-29 19:34 ` Dan Williams
2015-05-29 20:10 ` Toshi Kani
2015-05-29 18:34 ` Andy Lutomirski
2015-05-29 19:32 ` Dan Williams
2015-05-29 21:29 ` Elliott, Robert (Server Storage)
2015-05-29 21:46 ` Andy Lutomirski
2015-05-29 22:24 ` Elliott, Robert (Server Storage)
2015-05-29 22:32 ` H. Peter Anvin
2015-06-01 8:58 ` Ingo Molnar
2015-06-01 17:10 ` Andy Lutomirski
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