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powerpc/perf/hv-24x7: use kmem_cache instead of aligned stack allocations

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Ian pointed out the use of __aligned(4096) caused rather large stack
consumption in single_24x7_request(), so use the kmem_cache
hv_page_cache (which we've already got set up for other allocations)
insead of allocating locally.

CC: Haren Myneni <hbabu@us.ibm.com>
Reported-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Cody P Schafer <dev@codyps.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Cody P Schafer 2014-09-30 23:03:17 -07:00 committed by Michael Ellerman
parent bf7588a085
commit 48bee8a6c9
1 changed files with 37 additions and 18 deletions
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55
arch/powerpc/perf/hv-24x7.c
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@ -294,7 +294,7 @@ static unsigned long single_24x7_request(u8 domain, u32 offset, u16 ix,
u16 lpar, u64 *res,
bool success_expected)
{
unsigned long ret;
unsigned long ret = -ENOMEM;
/*
* request_buffer and result_buffer are not required to be 4k aligned,
@ -304,7 +304,27 @@ static unsigned long single_24x7_request(u8 domain, u32 offset, u16 ix,
struct reqb {
struct hv_24x7_request_buffer buf;
struct hv_24x7_request req;
} __packed __aligned(4096) request_buffer = {
} __packed *request_buffer;
struct {
struct hv_24x7_data_result_buffer buf;
struct hv_24x7_result res;
struct hv_24x7_result_element elem;
__be64 result;
} __packed *result_buffer;
BUILD_BUG_ON(sizeof(*request_buffer) > 4096);
BUILD_BUG_ON(sizeof(*result_buffer) > 4096);
request_buffer = kmem_cache_zalloc(hv_page_cache, GFP_USER);
if (!request_buffer)
goto out;
result_buffer = kmem_cache_zalloc(hv_page_cache, GFP_USER);
if (!result_buffer)
goto out_free_request_buffer;
*request_buffer = (struct reqb) {
.buf = {
.interface_version = HV_24X7_IF_VERSION_CURRENT,
.num_requests = 1,
@ -320,28 +340,27 @@ static unsigned long single_24x7_request(u8 domain, u32 offset, u16 ix,
}
};
struct resb {
struct hv_24x7_data_result_buffer buf;
struct hv_24x7_result res;
struct hv_24x7_result_element elem;
__be64 result;
} __packed __aligned(4096) result_buffer = {};
ret = plpar_hcall_norets(H_GET_24X7_DATA,
virt_to_phys(&request_buffer), sizeof(request_buffer),
virt_to_phys(&result_buffer), sizeof(result_buffer));
virt_to_phys(request_buffer), sizeof(*request_buffer),
virt_to_phys(result_buffer), sizeof(*result_buffer));
if (ret) {
if (success_expected)
pr_err_ratelimited("hcall failed: %d %#x %#x %d => 0x%lx (%ld) detail=0x%x failing ix=%x\n",
domain, offset, ix, lpar,
ret, ret,
result_buffer.buf.detailed_rc,
result_buffer.buf.failing_request_ix);
return ret;
pr_err_ratelimited("hcall failed: %d %#x %#x %d => "
"0x%lx (%ld) detail=0x%x failing ix=%x\n",
domain, offset, ix, lpar, ret, ret,
result_buffer->buf.detailed_rc,
result_buffer->buf.failing_request_ix);
goto out_free_result_buffer;
}
*res = be64_to_cpu(result_buffer.result);
*res = be64_to_cpu(result_buffer->result);
out_free_result_buffer:
kfree(result_buffer);
out_free_request_buffer:
kfree(request_buffer);
out:
return ret;
}