lkml.org 
[lkml]   [2016]   [Dec]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 06/15] hyperv: avoid unnecessary vmalloc
Date
Make hypercall and tsc page allocation similar to the rest of the
Hyper-V shared memory stuff instead of vmalloc-ing them.

Also perform cleanup unconditionally which is safe.

TODO: the skipping of free in case of a crash is probably no longer
necessary, too.

Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
---
drivers/hv/hv.c | 42 ++++++++++++++++++------------------------
1 file changed, 18 insertions(+), 24 deletions(-)

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 6bbc0b09..b40c7d9 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -29,6 +29,7 @@
#include <linux/version.h>
#include <linux/interrupt.h>
#include <linux/clockchips.h>
+#include <asm/cacheflush.h>
#include <asm/hyperv.h>
#include <asm/mshyperv.h>
#include "hyperv_vmbus.h"
@@ -208,14 +209,15 @@ int hv_init(void)
/* See if the hypercall page is already set */
rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);

- virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
-
- if (!virtaddr)
+ virtaddr = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!virtaddr || set_memory_x((unsigned long)virtaddr, 1))
goto cleanup;
+ hv_context.hypercall_page = virtaddr;

hypercall_msr.enable = 1;

- hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr);
+ hypercall_msr.guest_physical_address =
+ virt_to_phys(virtaddr) >> PAGE_SHIFT;
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);

/* Confirm that hypercall page did get setup. */
@@ -225,14 +227,12 @@ int hv_init(void)
if (!hypercall_msr.enable)
goto cleanup;

- hv_context.hypercall_page = virtaddr;
-
#ifdef CONFIG_X86_64
if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) {
union hv_x64_msr_hypercall_contents tsc_msr;
void *va_tsc;

- va_tsc = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL);
+ va_tsc = (void *)get_zeroed_page(GFP_KERNEL);
if (!va_tsc)
goto cleanup;
hv_context.tsc_page = va_tsc;
@@ -240,7 +240,8 @@ int hv_init(void)
rdmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64);

tsc_msr.enable = 1;
- tsc_msr.guest_physical_address = vmalloc_to_pfn(va_tsc);
+ tsc_msr.guest_physical_address =
+ virt_to_phys(va_tsc) >> PAGE_SHIFT;

wrmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64);
clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100);
@@ -249,14 +250,9 @@ int hv_init(void)
return 0;

cleanup:
- if (virtaddr) {
- if (hypercall_msr.enable) {
- hypercall_msr.as_uint64 = 0;
- wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
- }
-
- vfree(virtaddr);
- }
+ hypercall_msr.as_uint64 = 0;
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+ free_page((unsigned long)virtaddr);

return -ENOTSUPP;
}
@@ -273,13 +269,11 @@ void hv_cleanup(bool crash)
/* Reset our OS id */
wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);

- if (hv_context.hypercall_page) {
- hypercall_msr.as_uint64 = 0;
- wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
- if (!crash)
- vfree(hv_context.hypercall_page);
- hv_context.hypercall_page = NULL;
- }
+ hypercall_msr.as_uint64 = 0;
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+ if (!crash)
+ free_page((unsigned long)hv_context.hypercall_page);
+ hv_context.hypercall_page = NULL;

#ifdef CONFIG_X86_64
/*
@@ -298,7 +292,7 @@ void hv_cleanup(bool crash)
hypercall_msr.as_uint64 = 0;
wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64);
if (!crash)
- vfree(hv_context.tsc_page);
+ free_page((unsigned long)hv_context.tsc_page);
hv_context.tsc_page = NULL;
}
#endif
--
2.9.3
\
 
 \ /
  Last update: 2016-12-20 19:29    [W:0.481 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site