linux-kernel - [PATCH 1/3] soc: qcom: rpmh-rsc: Remove tcs_is

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200424045414.133381-2-swboyd@chromium.org>
Date:   Thu, 23 Apr 2020 21:54:12 -0700
From:   Stephen Boyd <swboyd@...omium.org>
To:     Andy Gross <agross@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>
Cc:     linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        Maulik Shah <mkshah@...eaurora.org>,
        Douglas Anderson <dianders@...omium.org>
Subject: [PATCH 1/3] soc: qcom: rpmh-rsc: Remove tcs_is_free() API

This API does very little. Let's replace all the callsites with the
normal operations that would be done on top of the bitmap that
tcs_in_use is. This simplifies and reduces the code size.

Cc: Maulik Shah <mkshah@...eaurora.org>
Cc: Douglas Anderson <dianders@...omium.org>
Signed-off-by: Stephen Boyd <swboyd@...omium.org>
---
 drivers/soc/qcom/rpmh-rsc.c | 56 +++++++++++--------------------------
 1 file changed, 17 insertions(+), 39 deletions(-)

diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index 060be10bc491..76e0294a672c 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -172,22 +172,6 @@ static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id,
 	}
 }
 
-/**
- * tcs_is_free() - Return if a TCS is totally free.
- * @drv:    The RSC controller.
- * @tcs_id: The global ID of this TCS.
- *
- * Returns true if nobody has claimed this TCS (by setting tcs_in_use).
- *
- * Context: Must be called with the drv->lock held.
- *
- * Return: true if the given TCS is free.
- */
-static bool tcs_is_free(struct rsc_drv *drv, int tcs_id)
-{
-	return !test_bit(tcs_id, drv->tcs_in_use);
-}
-
 /**
  * tcs_invalidate() - Invalidate all TCSes of the given type (sleep or wake).
  * @drv:  The RSC controller.
@@ -500,7 +484,7 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id,
  *
  * Return: 0 if nothing in flight or -EBUSY if we should try again later.
  *         The caller must re-enable interrupts between tries since that's
- *         the only way tcs_is_free() will ever return true and the only way
+ *         the only way tcs_in_use will ever be updated and the only way
  *         RSC_DRV_CMD_ENABLE will ever be cleared.
  */
 static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
@@ -508,17 +492,14 @@ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
 {
 	unsigned long curr_enabled;
 	u32 addr;
-	int i, j, k;
-	int tcs_id = tcs->offset;
+	int j, k;
+	int i = tcs->offset;
 
-	for (i = 0; i < tcs->num_tcs; i++, tcs_id++) {
-		if (tcs_is_free(drv, tcs_id))
-			continue;
-
-		curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id);
+	for_each_set_bit_from(i, drv->tcs_in_use, tcs->offset + tcs->num_tcs) {
+		curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i);
 
 		for_each_set_bit(j, &curr_enabled, MAX_CMDS_PER_TCS) {
-			addr = read_tcs_cmd(drv, RSC_DRV_CMD_ADDR, tcs_id, j);
+			addr = read_tcs_cmd(drv, RSC_DRV_CMD_ADDR, i, j);
 			for (k = 0; k < msg->num_cmds; k++) {
 				if (addr == msg->cmds[k].addr)
 					return -EBUSY;
@@ -536,18 +517,18 @@ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
  *
  * Must be called with the drv->lock held since that protects tcs_in_use.
  *
- * Return: The first tcs that's free.
+ * Return: The first tcs that's free or -EBUSY if all in use.
  */
 static int find_free_tcs(struct tcs_group *tcs)
 {
-	int i;
+	const struct rsc_drv *drv = tcs->drv;
+	unsigned long i;
 
-	for (i = 0; i < tcs->num_tcs; i++) {
-		if (tcs_is_free(tcs->drv, tcs->offset + i))
-			return tcs->offset + i;
-	}
+	i = find_next_zero_bit(drv->tcs_in_use, MAX_TCS_NR, tcs->offset);
+	if (i > tcs->offset + tcs->num_tcs)
+		return -EBUSY;
 
-	return -EBUSY;
+	return i;
 }
 
 /**
@@ -744,8 +725,8 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg)
  */
 static bool rpmh_rsc_ctrlr_is_busy(struct rsc_drv *drv)
 {
-	int m;
-	struct tcs_group *tcs = &drv->tcs[ACTIVE_TCS];
+	unsigned long set;
+	const struct tcs_group *tcs = &drv->tcs[ACTIVE_TCS];
 
 	/*
 	 * If we made an active request on a RSC that does not have a
@@ -756,12 +737,9 @@ static bool rpmh_rsc_ctrlr_is_busy(struct rsc_drv *drv)
 	if (!tcs->num_tcs)
 		tcs = &drv->tcs[WAKE_TCS];
 
-	for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) {
-		if (!tcs_is_free(drv, m))
-			return true;
-	}
+	set = find_next_bit(drv->tcs_in_use, MAX_TCS_NR, tcs->offset);
 
-	return false;
+	return set < tcs->offset + tcs->num_tcs;
 }
 
 /**
-- 
Sent by a computer, using git, on the internet