Tracing allocators of virtual memory and main memory
Hi all If i want to trace the allocators of virtual memory and main memory of process using ftrace on which functions i need to enable the probe.? Currently i have enabled sys_mmap,sys_brk for virtual allocations and mm_page_alloc, kmalloc, kmem_cache_alloc for main memory allocation. Will this give me whole picture of virtual and main memory allocations.? Thanks Regards Sahil ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: confusing code....whats the point of this construct ?
Now I am confused. I thought the code where empty and skip are inside the wait_event_timeout leads to empty beeing evaluated every time that the waiting threads gets awoken. And since some other thread might change /ar-htt.num_pending_tx/ it is necessary to check this every time we get awoken, rather than once before we go to sleep. Also the locking part arround empty seems to support my guess (why sync if you do not have multiple threads accessing a variable). These are only guesses without looking at the surrounding code. Could you please explain why you think it is sufficient to evaluate the condition only once before sleeping on it? (empty || skip) is a constant if you do not update either empty or skip, at least from my point of view. On 11/03/15 14:40, valdis.kletni...@vt.edu wrote: On Wed, 11 Mar 2015 15:17:44 +0100, Nicholas Mc Guire said: So the wait_event_timeout condition here ends up being (empty || skip) but what is the point of puting this code into the parameter list of wait_event_timeout() ? Would it not be equivalent to: bool empty; ... spin_lock_bh(ar-htt.tx_lock); empty = (ar-htt.num_pending_tx == 0); spin_unlock_bh(ar-htt.tx_lock); skip = (ar-state == ATH10K_STATE_WEDGED) || test_bit(ATH10K_FLAG_CRASH_FLUSH, ar-dev_flags); ret = wait_event_timeout(ar-htt.empty_tx_wq, (empty || skip), ATH10K_FLUSH_TIMEOUT_HZ); What am I missing here ? Umm... a Signed-off-by: and formatting it as an actual patch? :) Seriously - you're right, it's ugly code that needs fixing... ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: confusing code....whats the point of this construct ?
On Wed, 11 Mar 2015, Bj??rn Mork wrote:
valdis.kletni...@vt.edu writes:
On Wed, 11 Mar 2015 15:17:44 +0100, Nicholas Mc Guire said:
So the wait_event_timeout condition here ends up being (empty || skip)
but what is the point of puting this code into the parameter list of
wait_event_timeout() ?
Would it not be equivalent to:
bool empty;
...
spin_lock_bh(ar-htt.tx_lock);
empty = (ar-htt.num_pending_tx == 0);
spin_unlock_bh(ar-htt.tx_lock);
skip = (ar-state == ATH10K_STATE_WEDGED) ||
test_bit(ATH10K_FLAG_CRASH_FLUSH,
ar-dev_flags);
ret = wait_event_timeout(ar-htt.empty_tx_wq, (empty || skip),
ATH10K_FLUSH_TIMEOUT_HZ);
What am I missing here ?
Umm... a Signed-off-by: and formatting it as an actual patch? :)
Seriously - you're right, it's ugly code that needs fixing...
Huh?
The condition needs to be re-evaluated every time the process wakes up.
Evaluating it once and then reusing that result is not the same.
Something elseis supposed to modify ar-htt.num_pending_tx, ar-state or
ar-dev_flags while we are waiting.
after picking appart the mac.i file I see what you mean
(a bit reformated to make it kind of readable)
ret = ({ long __ret = (5*250);
do { _cond_resched(); } while (0);
if (!({
bool __cond = (({
bool empty;
spin_lock_bh(ar-htt.tx_lock);
empty = (ar-htt.num_pending_tx == 0);
spin_unlock_bh(ar-htt.tx_lock);
skip = (ar-state == ATH10K_STATE_WEDGED) ||
(__builtin_constant_p((ATH10K_FLAG_CRASH_FLUSH)) ?
constant_test_bit((ATH10K_FLAG_CRASH_FLUSH),
(ar-dev_flags)) :
variable_test_bit((ATH10K_FLAG_CRASH_FLUSH),
(ar-dev_flags)));
(empty || skip);
}));
if (__cond !__ret)
__ret = 1;
__cond || !__ret;
}))
__ret = ({ __label__ __out;
wait_queue_t __wait;
long __ret = (5*250);
INIT_LIST_HEAD(__wait.task_list);
if (0)
__wait.flags = 0x01;
else
__wait.flags = 0;
for (;;) {
long __int = prepare_to_wait_event(ar-htt.empty_tx_wq,
__wait, 2);
if (({
bool __cond = (({
bool empty;
spin_lock_bh(ar-htt.tx_lock);
empty = (ar-htt.num_pending_tx == 0);
spin_unlock_bh(ar-htt.tx_lock);
skip = (ar-state ==
ATH10K_STATE_WEDGED) || (__builtin_constant_p((ATH10K_FLAG_CRASH_FLUSH)) ?
constant_test_bit((ATH10K_FLAG_CRASH_FLUSH), (ar-dev_flags)) :
variable_test_bit((ATH10K_FLAG_CRASH_FLUSH), (ar-dev_flags)));
(empty || skip);
}));
i if (__cond !__ret)
__ret = 1;
__cond || !__ret;
}))
break;
if ((!__builtin_constant_p(2) || 2 == 1 || 2 == (128 |
2)) __int) {
__ret = __int;
if (0) {
abort_exclusive_wait(ar-htt.empty_tx_wq, __wait, 2, ((void *)0));
goto __out;
}
break;
}
__ret = schedule_timeout(__ret);
}
finish_wait(ar-htt.empty_tx_wq, __wait);
__out:
__ret;
});
__ret;
})
So the for(;;){ ... } is the part I missed at first.
but never the less the code should then pack up the inner block into a
static function and pass it to wait_event_timeout rather than
putting the basic block into the parameter list e.g. like in
drivers/gpu/drm/drm_dp_mst_topology.c:drm_dp_mst_wait_tx_reply()
static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_sideband_msg_tx *txmsg)
{
bool ret;
mutex_lock(mgr-qlock);
ret = (txmsg-state == DRM_DP_SIDEBAND_TX_RX ||
txmsg-state == DRM_DP_SIDEBAND_TX_TIMEOUT);
mutex_unlock(mgr-qlock);
return ret;
}
drm_dp_mst_wait_tx_reply()
snip
ret =
RE: confusing code....whats the point of this construct ?
On March 11, 2015 2:37:32 PM EDT, Jeff Haran jeff.ha...@citrix.com wrote:
-Original Message-
From: kernelnewbies-boun...@kernelnewbies.org
[mailto:kernelnewbies-boun...@kernelnewbies.org] On Behalf Of
valdis.kletni...@vt.edu
Sent: Wednesday, March 11, 2015 10:00 AM
To: Nicholas Mc Guire
Cc: Bj??rn Mork; kernelnewbies@kernelnewbies.org
Subject: Re: confusing codewhats the point of this construct ?
On Wed, 11 Mar 2015 17:46:56 +0100, Nicholas Mc Guire said:
ret = ({ long __ret = (5*250);
do { _cond_resched(); } while (0);
if (!({
bool __cond = (({
Gaak.
ret = wait_event_timeout(mgr-tx_waitq,
check_txmsg_state(mgr, txmsg),
(4 * HZ));
-EGADS - use of macro as a function violates the Principle of Least
Surprise
I have to wonder how many other places we've got bugs waiting to
happen because of this
I don't understand the problem here. The caller passes in a condition
to be evaluated in a loop. Many times that condition is quite simple
(e.g. a counter being non-zero). If it was a function the caller would
have to pass in a pointer to a function that does the evaluation, as
in:
int bar;
int foo(void)
{
return bar;
}
...
wait_event_interruptible(..., foo, ...);
Instead of the much simpler:
wait_event_interruptible(..., bar, ...);
That latter seems easier to understand and require fewer instructions
to be generated since there is no function call overhead.
Jeff Haran
Due to complaints about this code., I am requesting a vote for me to send in a
patch fixing this terribly ugly code. Please let me know about your results for
the
vote for me making a patch to fix this code.
Nick
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RE: confusing code....whats the point of this construct ?
-Original Message-
From: kernelnewbies-boun...@kernelnewbies.org
[mailto:kernelnewbies-boun...@kernelnewbies.org] On Behalf Of
valdis.kletni...@vt.edu
Sent: Wednesday, March 11, 2015 10:00 AM
To: Nicholas Mc Guire
Cc: Bj??rn Mork; kernelnewbies@kernelnewbies.org
Subject: Re: confusing codewhats the point of this construct ?
On Wed, 11 Mar 2015 17:46:56 +0100, Nicholas Mc Guire said:
ret = ({ long __ret = (5*250);
do { _cond_resched(); } while (0);
if (!({
bool __cond = (({
Gaak.
ret = wait_event_timeout(mgr-tx_waitq,
check_txmsg_state(mgr, txmsg),
(4 * HZ));
-EGADS - use of macro as a function violates the Principle of Least
Surprise
I have to wonder how many other places we've got bugs waiting to happen
because of this
I don't understand the problem here. The caller passes in a condition to be
evaluated in a loop. Many times that condition is quite simple (e.g. a counter
being non-zero). If it was a function the caller would have to pass in a
pointer to a function that does the evaluation, as in:
int bar;
int foo(void)
{
return bar;
}
...
wait_event_interruptible(..., foo, ...);
Instead of the much simpler:
wait_event_interruptible(..., bar, ...);
That latter seems easier to understand and require fewer instructions to be
generated since there is no function call overhead.
Jeff Haran
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RE: confusing code....whats the point of this construct ?
-Original Message- From: valdis.kletni...@vt.edu [mailto:valdis.kletni...@vt.edu] Sent: Wednesday, March 11, 2015 11:58 AM To: Jeff Haran Cc: Nicholas Mc Guire; Bj??rn Mork; kernelnewbies@kernelnewbies.org Subject: Re: confusing codewhats the point of this construct ? On Wed, 11 Mar 2015 18:37:32 -, Jeff Haran said: I don't understand the problem here. The caller passes in a condition to be evaluated in a loop. Many times that condition is quite simple (e.g. a counter being non-zero). If it was a function the caller would have to pass in a pointer to a function that does the evaluation, as in: We do pointers to callback functions all the time. We try *really* hard to avoid anonymous lambda functions (which is basically what we have here). The problem here is that there's about 3 zillion ways to screw up the inline version, starting with the compiler optimizing the control variable into a hoisted load outside the loop and causing the test to always fail - note that the macro does *not* use any barriers or volatile or anything like that. Dealing with those issues has to be a problem for the caller to solve in whatever condition code he decides to pass in, not the implementation of the macro itself. I agree with Nicholas M. that it would have been easier to read had the condition been packaged into an inline function, but if whoever writes that inline function gets the optimization/barriers wrong then its broken regardless of whether it's written inline like it is now or packaged into a separate inline function. As for volatile, I had thought that the usage of volatile in kernel code was generally discouraged. This construct is all over the place in the kernel. Changing theses wait macros into functions would be a big lift. Jeff Haran ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: confusing code....whats the point of this construct ?
On Wed, 11 Mar 2015, Jeff Haran wrote:
-Original Message-
From: kernelnewbies-boun...@kernelnewbies.org
[mailto:kernelnewbies-boun...@kernelnewbies.org] On Behalf Of
valdis.kletni...@vt.edu
Sent: Wednesday, March 11, 2015 10:00 AM
To: Nicholas Mc Guire
Cc: Bj??rn Mork; kernelnewbies@kernelnewbies.org
Subject: Re: confusing codewhats the point of this construct ?
On Wed, 11 Mar 2015 17:46:56 +0100, Nicholas Mc Guire said:
ret = ({ long __ret = (5*250);
do { _cond_resched(); } while (0);
if (!({
bool __cond = (({
Gaak.
ret = wait_event_timeout(mgr-tx_waitq,
check_txmsg_state(mgr, txmsg),
(4 * HZ));
-EGADS - use of macro as a function violates the Principle of Least
Surprise
I have to wonder how many other places we've got bugs waiting to happen
because of this
I don't understand the problem here. The caller passes in a condition to be
evaluated in a loop. Many times that condition is quite simple (e.g. a
counter being non-zero). If it was a function the caller would have to pass
in a pointer to a function that does the evaluation, as in:
int bar;
int foo(void)
{
return bar;
}
...
wait_event_interruptible(..., foo, ...);
Instead of the much simpler:
wait_event_interruptible(..., bar, ...);
That latter seems easier to understand and require fewer instructions to be
generated since there is no function call overhead.
for simle conditions that is true and commonly done but for
complex conditions that require locking or intermediate
variables it is much more readable if packed up in a function like in
e.g. see drivers/gpu/drm/drm_dp_mst_topology.c:drm_dp_mst_wait_tx_reply()
static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_sideband_msg_tx *txmsg)
{
bool ret;
mutex_lock(mgr-qlock);
ret = (txmsg-state == DRM_DP_SIDEBAND_TX_RX ||
txmsg-state == DRM_DP_SIDEBAND_TX_TIMEOUT);
mutex_unlock(mgr-qlock);
return ret;
}
drm_dp_mst_wait_tx_reply()
snip
ret = wait_event_timeout(mgr-tx_waitq,
check_txmsg_state(mgr, txmsg),
(4 * HZ));
snip
which I find is much simpler to understand than the inline code
in ath10k_flush().
thx!
hofrat
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Re: Tracing allocators of virtual memory and main memory
On March 11, 2015 12:07:29 PM EDT, sahil aggarwal sahil.ag...@gmail.com wrote: Hi all If i want to trace the allocators of virtual memory and main memory of process using ftrace on which functions i need to enable the probe.? Currently i have enabled sys_mmap,sys_brk for virtual allocations and mm_page_alloc, kmalloc, kmem_cache_alloc for main memory allocation. Will this give me whole picture of virtual and main memory allocations.? Thanks Regards Sahil __ Greetings Sachil, The best way to do this is find out the PID of your application and look for it in /proc as there should be a directory with the information your looking for. Nick Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- Sent from my Android device with K-9 Mail. Please excuse my brevity. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: confusing code....whats the point of this construct ?
On Wed, 11 Mar 2015 18:37:32 -, Jeff Haran said: I don't understand the problem here. The caller passes in a condition to be evaluated in a loop. Many times that condition is quite simple (e.g. a counter being non-zero). If it was a function the caller would have to pass in a pointer to a function that does the evaluation, as in: We do pointers to callback functions all the time. We try *really* hard to avoid anonymous lambda functions (which is basically what we have here). The problem here is that there's about 3 zillion ways to screw up the inline version, starting with the compiler optimizing the control variable into a hoisted load outside the loop and causing the test to always fail - note that the macro does *not* use any barriers or volatile or anything like that. pgp3aFNq2myUk.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Kernel Locking Question
Greetings All, After learning about kernel locking and how atomic operations are good in terms of improving CPU scalability in terms of making a critical region much smaller. I was wondering of how this would improve file system scalability and reliability if implemented in file system code for btrfs worker threads. Nick -- Sent from my Android device with K-9 Mail. Please excuse my brevity. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Kernel Locking Question
On Wed, 11 Mar 2015 19:03:33 -0400, Nicholas Krause said: was wondering of how this would improve file system scalability and reliability if implemented in file system code for btrfs worker threads. Step 1: Figure out what locks are contended in actual systems. Step 2: Determine if the scope of a contended lock can be reduced. Step 3: ??? Step 4: Profit! Note that improving scalability will often cause reliability issues, because as you decompose locks into sets of smaller locks, you increase the number of ways you can get it wrong. The BKL, for all its uglyness, was pretty hard to screw up. On the other hand, we probably would never have gotten rid of it if somebody hadn't put lockdep into the kernel. It was painful enough even with automated testing tools pgp54C1WDIDsf.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Tracing allocators of virtual memory and main memory
On Thu, 12 Mar 2015 07:09:32 +0530, SAHIL said: Yeah right, pidstat which read /proc gives me VSZ ans RSS but i need to backtrace when VSZ/RSS is high which indicates process is allocating memory which it is not even using. Do you mean pages it isn't *currently* using, or has *never* used? Also, note that VSZ refers to the virtual size, which may include pages currently out on swap, while RSS refers to actually resident pages. And then there's the other great bugaboo, shared pages that are mapped by more than one process. What exactly are you trying to do? pgpulN5XSF2vj.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Kernel preemption
Hi, guys: I have a device with only one CPU. I am wondering whether there will be only one task running on CPU and this task will not be interrupted by scheduler if I make the kernel non-preemptive ? At this situation, whether the time splice will not exist? Regards --- Rock Lee ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Tracing allocators of virtual memory and main memory
Hi validis Actually i want to see how much total virtual pages it asked for and how many it actually used, how many were put to swap, how many major page faults happened and how many faults were handled from swap. In short whole page level analysis of thread. Regards Sahil Aggarwal Contact-9988439647 On Mar 12, 2015, at 7:24 AM, valdis.kletni...@vt.edu wrote: On Thu, 12 Mar 2015 07:09:32 +0530, SAHIL said: Yeah right, pidstat which read /proc gives me VSZ ans RSS but i need to backtrace when VSZ/RSS is high which indicates process is allocating memory which it is not even using. Do you mean pages it isn't *currently* using, or has *never* used? Also, note that VSZ refers to the virtual size, which may include pages currently out on swap, while RSS refers to actually resident pages. And then there's the other great bugaboo, shared pages that are mapped by more than one process. What exactly are you trying to do? ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: confusing code....whats the point of this construct ?
On Wed, 11 Mar 2015 15:17:44 +0100, Nicholas Mc Guire said: So the wait_event_timeout condition here ends up being (empty || skip) but what is the point of puting this code into the parameter list of wait_event_timeout() ? Would it not be equivalent to: bool empty; ... spin_lock_bh(ar-htt.tx_lock); empty = (ar-htt.num_pending_tx == 0); spin_unlock_bh(ar-htt.tx_lock); skip = (ar-state == ATH10K_STATE_WEDGED) || test_bit(ATH10K_FLAG_CRASH_FLUSH, ar-dev_flags); ret = wait_event_timeout(ar-htt.empty_tx_wq, (empty || skip), ATH10K_FLUSH_TIMEOUT_HZ); What am I missing here ? Umm... a Signed-off-by: and formatting it as an actual patch? :) Seriously - you're right, it's ugly code that needs fixing... pgpwpqWJn4iCd.pgp Description: PGP signature ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: confusing code....whats the point of this construct ?
On Wed, 11 Mar 2015, valdis.kletni...@vt.edu wrote: On Wed, 11 Mar 2015 15:17:44 +0100, Nicholas Mc Guire said: So the wait_event_timeout condition here ends up being (empty || skip) but what is the point of puting this code into the parameter list of wait_event_timeout() ? Would it not be equivalent to: bool empty; ... spin_lock_bh(ar-htt.tx_lock); empty = (ar-htt.num_pending_tx == 0); spin_unlock_bh(ar-htt.tx_lock); skip = (ar-state == ATH10K_STATE_WEDGED) || test_bit(ATH10K_FLAG_CRASH_FLUSH, ar-dev_flags); ret = wait_event_timeout(ar-htt.empty_tx_wq, (empty || skip), ATH10K_FLUSH_TIMEOUT_HZ); What am I missing here ? Umm... a Signed-off-by: and formatting it as an actual patch? :) Seriously - you're right, it's ugly code that needs fixing... thats what I thought too but it seemed to be intentional so I was just confused if it were some strange side-effect that I had not understood. thanks for the clarification ! hofrat ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
confusing code....whats the point of this construct ?
HI !
Trying to understand the intent of this code construct
drivers/net/wireless/ath/ath10k/mac.c:ath10k_flush()
snip
ret = wait_event_timeout(ar-htt.empty_tx_wq, ({
bool empty;
spin_lock_bh(ar-htt.tx_lock);
empty = (ar-htt.num_pending_tx == 0);
spin_unlock_bh(ar-htt.tx_lock);
skip = (ar-state == ATH10K_STATE_WEDGED) ||
test_bit(ATH10K_FLAG_CRASH_FLUSH,
ar-dev_flags);
(empty || skip);
}), ATH10K_FLUSH_TIMEOUT_HZ);
snip
FYI include/linux/wait.h:wait_event_timeout()
snip
* wait_event_timeout - sleep until a condition gets true or a timeout elapses
* @wq: the waitqueue to wait on
* @condition: a C expression for the event to wait for
* @timeout: timeout, in jiffies
snip
So the wait_event_timeout condition here ends up being (empty || skip)
but what is the point of puting this code into the parameter list of
wait_event_timeout() ?
Would it not be equivalent to:
bool empty;
...
spin_lock_bh(ar-htt.tx_lock);
empty = (ar-htt.num_pending_tx == 0);
spin_unlock_bh(ar-htt.tx_lock);
skip = (ar-state == ATH10K_STATE_WEDGED) ||
test_bit(ATH10K_FLAG_CRASH_FLUSH,
ar-dev_flags);
ret = wait_event_timeout(ar-htt.empty_tx_wq, (empty || skip),
ATH10K_FLUSH_TIMEOUT_HZ);
What am I missing here ?
thx!
hofrat
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Re: Kernel Locking Question
On 2015-03-11 09:48 PM, valdis.kletni...@vt.edu wrote: On Wed, 11 Mar 2015 19:03:33 -0400, Nicholas Krause said: was wondering of how this would improve file system scalability and reliability if implemented in file system code for btrfs worker threads. Step 1: Figure out what locks are contended in actual systems. Step 2: Determine if the scope of a contended lock can be reduced. Step 3: ??? Step 4: Profit! Note that improving scalability will often cause reliability issues, because as you decompose locks into sets of smaller locks, you increase the number of ways you can get it wrong. The BKL, for all its uglyness, was pretty hard to screw up. On the other hand, we probably would never have gotten rid of it if somebody hadn't put lockdep into the kernel. It was painful enough even with automated testing tools Thanks Valdis, That makes sense to me. I was wondering however about the reader vs writer issues in file systems too as this seems to me coming up a lot in btrfs and other file systems for various reasons. Thanks Nick ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Re: Tracing allocators of virtual memory and main memory
Hi Nicholas Yeah right, pidstat which read /proc gives me VSZ ans RSS but i need to backtrace when VSZ/RSS is high which indicates process is allocating memory which it is not even using. And to modify the question i need to analyze allocations per thread, using /proc will it will also include VSZ RSS of parent.? Regards Sahil Aggarwal On Mar 11, 2015, at 11:00 PM, Nicholas Krause xerofo...@gmail.com wrote: On March 11, 2015 12:07:29 PM EDT, sahil aggarwal sahil.ag...@gmail.com wrote: Hi all If i want to trace the allocators of virtual memory and main memory of process using ftrace on which functions i need to enable the probe.? Currently i have enabled sys_mmap,sys_brk for virtual allocations and mm_page_alloc, kmalloc, kmem_cache_alloc for main memory allocation. Will this give me whole picture of virtual and main memory allocations.? Thanks Regards Sahil __ Greetings Sachil, The best way to do this is find out the PID of your application and look for it in /proc as there should be a directory with the information your looking for. Nick Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- Sent from my Android device with K-9 Mail. Please excuse my brevity. ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
