From 145264e2129a5e2fca9bc75f666e80424020f9ea Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Mon, 30 Mar 2015 18:53:38 -0700 Subject: [PATCH] powerpc/perf/hv-24x7: Modify definition of request and result buffers The parameters to the 24x7 HCALL have variable number of elements in them. Set the minimum number of such elements to 1 rather than 0 and eliminate the temporary structures. This would enable us to submit multiple counter requests and process multiple results from a single HCALL (in a follow on patch). Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Michael Ellerman --- arch/powerpc/perf/hv-24x7.c | 77 ++++++++++++++++++------------------- arch/powerpc/perf/hv-24x7.h | 8 ++-- 2 files changed, 41 insertions(+), 44 deletions(-) diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c index 9445a824819e..408e6e9ff449 100644 --- a/arch/powerpc/perf/hv-24x7.c +++ b/arch/powerpc/perf/hv-24x7.c @@ -142,6 +142,15 @@ static struct attribute_group event_long_desc_group = { static struct kmem_cache *hv_page_cache; +/* + * request_buffer and result_buffer are not required to be 4k aligned, + * but are not allowed to cross any 4k boundary. Aligning them to 4k is + * the simplest way to ensure that. + */ +#define H24x7_DATA_BUFFER_SIZE 4096 +DEFINE_PER_CPU(char, hv_24x7_reqb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); +DEFINE_PER_CPU(char, hv_24x7_resb[H24x7_DATA_BUFFER_SIZE]) __aligned(4096); + static char *event_name(struct hv_24x7_event_data *ev, int *len) { *len = be16_to_cpu(ev->event_name_len) - 2; @@ -976,31 +985,16 @@ static const struct attribute_group *attr_groups[] = { NULL, }; -DEFINE_PER_CPU(char, hv_24x7_reqb[4096]) __aligned(4096); -DEFINE_PER_CPU(char, hv_24x7_resb[4096]) __aligned(4096); - static unsigned long single_24x7_request(u8 domain, u32 offset, u16 ix, - u16 lpar, u64 *res, + u16 lpar, u64 *count, bool success_expected) { unsigned long ret; - /* - * request_buffer and result_buffer are not required to be 4k aligned, - * but are not allowed to cross any 4k boundary. Aligning them to 4k is - * the simplest way to ensure that. - */ - struct reqb { - struct hv_24x7_request_buffer buf; - struct hv_24x7_request req; - } __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; + struct hv_24x7_request_buffer *request_buffer; + struct hv_24x7_data_result_buffer *result_buffer; + struct hv_24x7_result *resb; + struct hv_24x7_request *req; BUILD_BUG_ON(sizeof(*request_buffer) > 4096); BUILD_BUG_ON(sizeof(*result_buffer) > 4096); @@ -1011,38 +1005,41 @@ static unsigned long single_24x7_request(u8 domain, u32 offset, u16 ix, memset(request_buffer, 0, 4096); memset(result_buffer, 0, 4096); - *request_buffer = (struct reqb) { - .buf = { - .interface_version = HV_24X7_IF_VERSION_CURRENT, - .num_requests = 1, - }, - .req = { - .performance_domain = domain, - .data_size = cpu_to_be16(8), - .data_offset = cpu_to_be32(offset), - .starting_lpar_ix = cpu_to_be16(lpar), - .max_num_lpars = cpu_to_be16(1), - .starting_ix = cpu_to_be16(ix), - .max_ix = cpu_to_be16(1), - } - }; + request_buffer->interface_version = HV_24X7_IF_VERSION_CURRENT; + request_buffer->num_requests = 1; + + req = &request_buffer->requests[0]; + req->performance_domain = domain; + req->data_size = cpu_to_be16(8); + req->data_offset = cpu_to_be32(offset); + req->starting_lpar_ix = cpu_to_be16(lpar), + req->max_num_lpars = cpu_to_be16(1); + req->starting_ix = cpu_to_be16(ix); + req->max_ix = cpu_to_be16(1); + + /* + * NOTE: Due to variable number of array elements in request and + * result buffer(s), sizeof() is not reliable. Use the actual + * allocated buffer size, H24x7_DATA_BUFFER_SIZE. + */ 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), H24x7_DATA_BUFFER_SIZE, + virt_to_phys(result_buffer), H24x7_DATA_BUFFER_SIZE); 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); + result_buffer->detailed_rc, + result_buffer->failing_request_ix); goto out; } - *res = be64_to_cpu(result_buffer->result); + resb = &result_buffer->results[0]; + *count = be64_to_cpu(resb->elements[0].element_data[0]); out: return ret; } diff --git a/arch/powerpc/perf/hv-24x7.h b/arch/powerpc/perf/hv-24x7.h index 69cd4e690f58..0f9fa21a29f2 100644 --- a/arch/powerpc/perf/hv-24x7.h +++ b/arch/powerpc/perf/hv-24x7.h @@ -50,7 +50,7 @@ struct hv_24x7_request_buffer { __u8 interface_version; __u8 num_requests; __u8 reserved[0xE]; - struct hv_24x7_request requests[]; + struct hv_24x7_request requests[1]; } __packed; struct hv_24x7_result_element { @@ -66,7 +66,7 @@ struct hv_24x7_result_element { __be32 lpar_cfg_instance_id; /* size = @result_element_data_size of cointaining result. */ - __u8 element_data[]; + __u64 element_data[1]; } __packed; struct hv_24x7_result { @@ -87,7 +87,7 @@ struct hv_24x7_result { /* WARNING: only valid for first result element due to variable sizes * of result elements */ /* struct hv_24x7_result_element[@num_elements_returned] */ - struct hv_24x7_result_element elements[]; + struct hv_24x7_result_element elements[1]; } __packed; struct hv_24x7_data_result_buffer { @@ -103,7 +103,7 @@ struct hv_24x7_data_result_buffer { __u8 reserved2[0x8]; /* WARNING: only valid for the first result due to variable sizes of * results */ - struct hv_24x7_result results[]; /* [@num_results] */ + struct hv_24x7_result results[1]; /* [@num_results] */ } __packed; #endif -- 2.39.5