s390/zcrypt: tracepoint definitions for zcrypt device driver.

This patch introduces tracepoint definitions and tracepoint
event invocations for the s390 zcrypt device.

Currently there are just two tracepoint events defined.
An s390_zcrypt_req request event occurs as soon as the
request is recognized by the zcrypt ioctl function. This
event may act as some kind of request-processing-starts-now
indication.
As late as possible within the zcrypt ioctl function there
occurs the s390_zcrypt_rep event which may act as the point
in time where the request has been processed by the kernel
and the result is about to be transferred back to userspace.
The glue which binds together request and reply event is the
ptr parameter, which is the local buffer address where the
request from userspace has been stored by the ioctl function.

The main purpose of this zcrypt tracepoint patch is to get
some data for performance measurements together with
information about the kind of request and on which card and
queue the request has been processed. It is not an ffdc
interface as there is already code in the zcrypt device
driver to serve the s390 debug feature interface.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 81 insertions, 24 deletions

diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c
index 7ca25e77bd6a..854a6e58dfea 100644
--- a/drivers/s390/crypto/zcrypt_api.c
+++ b/drivers/s390/crypto/zcrypt_api.c
@@ -41,6 +41,9 @@
 #include <linux/debugfs.h>
 #include <asm/debug.h>
 
+#define CREATE_TRACE_POINTS
+#include <asm/trace/zcrypt.h>
+
 #include "zcrypt_api.h"
 #include "zcrypt_debug.h"
 
@@ -55,6 +58,12 @@ MODULE_DESCRIPTION("Cryptographic Coprocessor interface, " \
 		   "Copyright IBM Corp. 2001, 2012");
 MODULE_LICENSE("GPL");
 
+/*
+ * zcrypt tracepoint functions
+ */
+EXPORT_TRACEPOINT_SYMBOL(s390_zcrypt_req);
+EXPORT_TRACEPOINT_SYMBOL(s390_zcrypt_rep);
+
 static int zcrypt_hwrng_seed = 1;
 module_param_named(hwrng_seed, zcrypt_hwrng_seed, int, S_IRUSR|S_IRGRP);
 MODULE_PARM_DESC(hwrng_seed, "Turn on/off hwrng auto seed, default is 1 (on).");
@@ -224,10 +233,15 @@ static long zcrypt_rsa_modexpo(struct ica_rsa_modexpo *mex)
 	struct zcrypt_queue *zq, *pref_zq;
 	unsigned int weight, pref_weight;
 	unsigned int func_code;
-	int rc;
+	int qid = 0, rc = -ENODEV;
+
+	trace_s390_zcrypt_req(mex, TP_ICARSAMODEXPO);
+
+	if (mex->outputdatalength < mex->inputdatalength) {
+		rc = -EINVAL;
+		goto out;
+	}
 
-	if (mex->outputdatalength < mex->inputdatalength)
-		return -EINVAL;
 	/*
 	 * As long as outputdatalength is big enough, we can set the
 	 * outputdatalength equal to the inputdatalength, since that is the
@@ -237,7 +251,7 @@ static long zcrypt_rsa_modexpo(struct ica_rsa_modexpo *mex)
 
 	rc = get_rsa_modex_fc(mex, &func_code);
 	if (rc)
-		return rc;
+		goto out;
 
 	pref_zc = NULL;
 	pref_zq = NULL;
@@ -269,15 +283,21 @@ static long zcrypt_rsa_modexpo(struct ica_rsa_modexpo *mex)
 	pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
 
-	if (!pref_zq)
-		return -ENODEV;
+	if (!pref_zq) {
+		rc = -ENODEV;
+		goto out;
+	}
 
+	qid = pref_zq->queue->qid;
 	rc = pref_zq->ops->rsa_modexpo(pref_zq, mex);
 
 	spin_lock(&zcrypt_list_lock);
 	zcrypt_drop_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
 
+out:
+	trace_s390_zcrypt_rep(mex, func_code, rc,
+			      AP_QID_CARD(qid), AP_QID_QUEUE(qid));
 	return rc;
 }
 
@@ -287,10 +307,15 @@ static long zcrypt_rsa_crt(struct ica_rsa_modexpo_crt *crt)
 	struct zcrypt_queue *zq, *pref_zq;
 	unsigned int weight, pref_weight;
 	unsigned int func_code;
-	int rc;
+	int qid = 0, rc = -ENODEV;
+
+	trace_s390_zcrypt_req(crt, TP_ICARSACRT);
+
+	if (crt->outputdatalength < crt->inputdatalength) {
+		rc = -EINVAL;
+		goto out;
+	}
 
-	if (crt->outputdatalength < crt->inputdatalength)
-		return -EINVAL;
 	/*
 	 * As long as outputdatalength is big enough, we can set the
 	 * outputdatalength equal to the inputdatalength, since that is the
@@ -300,7 +325,7 @@ static long zcrypt_rsa_crt(struct ica_rsa_modexpo_crt *crt)
 
 	rc = get_rsa_crt_fc(crt, &func_code);
 	if (rc)
-		return rc;
+		goto out;
 
 	pref_zc = NULL;
 	pref_zq = NULL;
@@ -332,15 +357,21 @@ static long zcrypt_rsa_crt(struct ica_rsa_modexpo_crt *crt)
 	pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
 
-	if (!pref_zq)
-		return -ENODEV;
+	if (!pref_zq) {
+		rc = -ENODEV;
+		goto out;
+	}
 
+	qid = pref_zq->queue->qid;
 	rc = pref_zq->ops->rsa_modexpo_crt(pref_zq, crt);
 
 	spin_lock(&zcrypt_list_lock);
 	zcrypt_drop_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
 
+out:
+	trace_s390_zcrypt_rep(crt, func_code, rc,
+			      AP_QID_CARD(qid), AP_QID_QUEUE(qid));
 	return rc;
 }
 
@@ -352,11 +383,13 @@ static long zcrypt_send_cprb(struct ica_xcRB *xcRB)
 	unsigned int weight, pref_weight;
 	unsigned int func_code;
 	unsigned short *domain;
-	int rc;
+	int qid = 0, rc = -ENODEV;
+
+	trace_s390_zcrypt_req(xcRB, TB_ZSECSENDCPRB);
 
 	rc = get_cprb_fc(xcRB, &ap_msg, &func_code, &domain);
 	if (rc)
-		return rc;
+		goto out;
 
 	pref_zc = NULL;
 	pref_zq = NULL;
@@ -391,18 +424,25 @@ static long zcrypt_send_cprb(struct ica_xcRB *xcRB)
 	pref_zq = zcrypt_pick_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
 
-	if (!pref_zq)
-		return -ENODEV;
+	if (!pref_zq) {
+		rc = -ENODEV;
+		goto out;
+	}
 
 	/* in case of auto select, provide the correct domain */
+	qid = pref_zq->queue->qid;
 	if (*domain == (unsigned short) AUTOSELECT)
-		*domain = AP_QID_QUEUE(pref_zq->queue->qid);
+		*domain = AP_QID_QUEUE(qid);
 
 	rc = pref_zq->ops->send_cprb(pref_zq, xcRB, &ap_msg);
 
 	spin_lock(&zcrypt_list_lock);
 	zcrypt_drop_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
+
+out:
+	trace_s390_zcrypt_rep(xcRB, func_code, rc,
+			      AP_QID_CARD(qid), AP_QID_QUEUE(qid));
 	return rc;
 }
 
@@ -439,7 +479,9 @@ static long zcrypt_send_ep11_cprb(struct ep11_urb *xcrb)
 	unsigned int weight, pref_weight;
 	unsigned int func_code;
 	struct ap_message ap_msg;
-	int rc;
+	int qid = 0, rc = -ENODEV;
+
+	trace_s390_zcrypt_req(xcrb, TP_ZSENDEP11CPRB);
 
 	target_num = (unsigned short) xcrb->targets_num;
 
@@ -449,13 +491,17 @@ static long zcrypt_send_ep11_cprb(struct ep11_urb *xcrb)
 		struct ep11_target_dev __user *uptr;
 
 		targets = kcalloc(target_num, sizeof(*targets), GFP_KERNEL);
-		if (!targets)
-			return -ENOMEM;
+		if (!targets) {
+			rc = -ENOMEM;
+			goto out;
+		}
 
 		uptr = (struct ep11_target_dev __force __user *) xcrb->targets;
 		if (copy_from_user(targets, uptr,
-				   target_num * sizeof(*targets)))
-			return -EFAULT;
+				   target_num * sizeof(*targets))) {
+			rc = -EFAULT;
+			goto out;
+		}
 	}
 
 	rc = get_ep11cprb_fc(xcrb, &ap_msg, &func_code);
@@ -501,6 +547,7 @@ static long zcrypt_send_ep11_cprb(struct ep11_urb *xcrb)
 		goto out_free;
 	}
 
+	qid = pref_zq->queue->qid;
 	rc = pref_zq->ops->send_ep11_cprb(pref_zq, xcrb, &ap_msg);
 
 	spin_lock(&zcrypt_list_lock);
@@ -509,6 +556,9 @@ static long zcrypt_send_ep11_cprb(struct ep11_urb *xcrb)
 
 out_free:
 	kfree(targets);
+out:
+	trace_s390_zcrypt_rep(xcrb, func_code, rc,
+			      AP_QID_CARD(qid), AP_QID_QUEUE(qid));
 	return rc;
 }
 
@@ -520,11 +570,13 @@ static long zcrypt_rng(char *buffer)
 	unsigned int func_code;
 	struct ap_message ap_msg;
 	unsigned int domain;
-	int rc;
+	int qid = 0, rc = -ENODEV;
+
+	trace_s390_zcrypt_req(buffer, TP_HWRNGCPRB);
 
 	rc = get_rng_fc(&ap_msg, &func_code, &domain);
 	if (rc)
-		return rc;
+		goto out;
 
 	pref_zc = NULL;
 	pref_zq = NULL;
@@ -555,11 +607,16 @@ static long zcrypt_rng(char *buffer)
 	if (!pref_zq)
 		return -ENODEV;
 
+	qid = pref_zq->queue->qid;
 	rc = pref_zq->ops->rng(pref_zq, buffer, &ap_msg);
 
 	spin_lock(&zcrypt_list_lock);
 	zcrypt_drop_queue(pref_zc, pref_zq, weight);
 	spin_unlock(&zcrypt_list_lock);
+
+out:
+	trace_s390_zcrypt_rep(buffer, func_code, rc,
+			      AP_QID_CARD(qid), AP_QID_QUEUE(qid));
 	return rc;
 }