From eefacf3b4f8a688aeaddd2f7c46ac5ffceb92472 Mon Sep 17 00:00:00 2001 From: David Graham Date: Thu, 8 Jan 2009 16:03:29 +0000 Subject: [PATCH] e1000e: Add process name to WARN message when detecting Mutex contention Adds process name of the current mutex holder to the WARN message output when the e1000e driver attempts to acquire the nvm_mutex and finds that it is already being held. With this patch the WARN message indicates both the process name of the current mutex holder and the process name of the attempted acquisition, which together will help to identify the contending codepaths. Signed-off-by: David Graham Acked-by: Bruce Allan Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/e1000e/ich8lan.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/net/e1000e/ich8lan.c b/drivers/net/e1000e/ich8lan.c index f2a5963b5a9..e415e81ecd3 100644 --- a/drivers/net/e1000e/ich8lan.c +++ b/drivers/net/e1000e/ich8lan.c @@ -390,7 +390,8 @@ static s32 e1000_get_variants_ich8lan(struct e1000_adapter *adapter) } static DEFINE_MUTEX(nvm_mutex); -static pid_t nvm_owner = -1; +static pid_t nvm_owner_pid = -1; +static char nvm_owner_name[TASK_COMM_LEN] = ""; /** * e1000_acquire_swflag_ich8lan - Acquire software control flag @@ -408,11 +409,15 @@ static s32 e1000_acquire_swflag_ich8lan(struct e1000_hw *hw) might_sleep(); if (!mutex_trylock(&nvm_mutex)) { - WARN(1, KERN_ERR "e1000e mutex contention. Owned by pid %d\n", - nvm_owner); + WARN(1, KERN_ERR "e1000e mutex contention. Owned by process " + "%s (pid %d), required by process %s (pid %d)\n", + nvm_owner_name, nvm_owner_pid, + current->comm, current->pid); + mutex_lock(&nvm_mutex); } - nvm_owner = current->pid; + nvm_owner_pid = current->pid; + strncpy(nvm_owner_name, current->comm, TASK_COMM_LEN); while (timeout) { extcnf_ctrl = er32(EXTCNF_CTRL); @@ -430,7 +435,8 @@ static s32 e1000_acquire_swflag_ich8lan(struct e1000_hw *hw) hw_dbg(hw, "FW or HW has locked the resource for too long.\n"); extcnf_ctrl &= ~E1000_EXTCNF_CTRL_SWFLAG; ew32(EXTCNF_CTRL, extcnf_ctrl); - nvm_owner = -1; + nvm_owner_pid = -1; + strcpy(nvm_owner_name, ""); mutex_unlock(&nvm_mutex); return -E1000_ERR_CONFIG; } @@ -454,7 +460,8 @@ static void e1000_release_swflag_ich8lan(struct e1000_hw *hw) extcnf_ctrl &= ~E1000_EXTCNF_CTRL_SWFLAG; ew32(EXTCNF_CTRL, extcnf_ctrl); - nvm_owner = -1; + nvm_owner_pid = -1; + strcpy(nvm_owner_name, ""); mutex_unlock(&nvm_mutex); } -- 2.41.1