[v8] eal: make lcore_config private

Message ID 20191002194024.28782-1-stephen@networkplumber.org (mailing list archive)
State Superseded, archived
Delegated to: David Marchand
Headers
Series [v8] eal: make lcore_config private |

Checks

Context Check Description
ci/checkpatch warning coding style issues
ci/Intel-compilation success Compilation OK
ci/iol-compilation success Compile Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS

Commit Message

Stephen Hemminger Oct. 2, 2019, 7:40 p.m. UTC
  The internal structure of lcore_config is no longer be part of
visible API/ABI. Make it private to EAL.

Rearrange and resize the fields in the structure so it takes
less memory (and cache footprint).

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
v8 - update release notes
     rearrange to move cpuset to second cache line

 doc/guides/rel_notes/deprecation.rst      |  4 ----
 doc/guides/rel_notes/release_19_11.rst    |  2 ++
 lib/librte_eal/common/eal_common_launch.c |  2 ++
 lib/librte_eal/common/eal_private.h       | 24 +++++++++++++++++++++++
 lib/librte_eal/common/include/rte_lcore.h | 24 -----------------------
 lib/librte_eal/common/rte_service.c       |  2 ++
 lib/librte_eal/rte_eal_version.map        |  1 -
 lib/librte_eal/windows/eal/eal_thread.c   |  1 +
 8 files changed, 31 insertions(+), 29 deletions(-)
  

Comments

David Marchand Oct. 22, 2019, 9:05 a.m. UTC | #1
On Wed, Oct 2, 2019 at 9:40 PM Stephen Hemminger
<stephen@networkplumber.org> wrote:
> +struct lcore_config {
> +       pthread_t thread_id;       /**< pthread identifier */
> +       int pipe_master2slave[2];  /**< communication pipe with master */
> +       int pipe_slave2master[2];  /**< communication pipe with master */
> +
> +       lcore_function_t * volatile f; /**< function to call */
> +       void * volatile arg;       /**< argument of function */
> +       volatile int ret;          /**< return value of function */
> +
> +       uint32_t core_id;          /**< core number on socket for this lcore */
> +       uint32_t core_index;       /**< relative index, starting from 0 */
> +       uint16_t socket_id;        /**< physical socket id for this lcore */
> +       uint8_t core_role;         /**< role of core eg: OFF, RTE, SERVICE */
> +       uint8_t detected;          /**< true if lcore was detected */
> +       volatile enum rte_lcore_state_t state; /**< lcore state */
> +       rte_cpuset_t cpuset;       /**< cpu set which the lcore affinity to */
> +};

There are still changes on the core_id, core_index, socket_id that I
am not confortable with (at this point).

I prepared a series for -rc1 on ABI changes in EAL (that I will send shortly).
I took your patch without the changes on core_id, core_index and socket_id.


We can discuss those changes later, thanks.
  
Stephen Hemminger Oct. 22, 2019, 4:30 p.m. UTC | #2
On Tue, 22 Oct 2019 11:05:01 +0200
David Marchand <david.marchand@redhat.com> wrote:

> On Wed, Oct 2, 2019 at 9:40 PM Stephen Hemminger
> <stephen@networkplumber.org> wrote:
> > +struct lcore_config {
> > +       pthread_t thread_id;       /**< pthread identifier */
> > +       int pipe_master2slave[2];  /**< communication pipe with master */
> > +       int pipe_slave2master[2];  /**< communication pipe with master */
> > +
> > +       lcore_function_t * volatile f; /**< function to call */
> > +       void * volatile arg;       /**< argument of function */
> > +       volatile int ret;          /**< return value of function */
> > +
> > +       uint32_t core_id;          /**< core number on socket for this lcore */
> > +       uint32_t core_index;       /**< relative index, starting from 0 */
> > +       uint16_t socket_id;        /**< physical socket id for this lcore */
> > +       uint8_t core_role;         /**< role of core eg: OFF, RTE, SERVICE */
> > +       uint8_t detected;          /**< true if lcore was detected */
> > +       volatile enum rte_lcore_state_t state; /**< lcore state */
> > +       rte_cpuset_t cpuset;       /**< cpu set which the lcore affinity to */
> > +};  
> 
> There are still changes on the core_id, core_index, socket_id that I
> am not confortable with (at this point).
> 
> I prepared a series for -rc1 on ABI changes in EAL (that I will send shortly).
> I took your patch without the changes on core_id, core_index and socket_id.


Why, please be more precise.

Do you expect to support more than 32 bit worth of cores?
  
David Marchand Oct. 22, 2019, 4:49 p.m. UTC | #3
On Tue, Oct 22, 2019 at 6:30 PM Stephen Hemminger
<stephen@networkplumber.org> wrote:
>
> On Tue, 22 Oct 2019 11:05:01 +0200
> David Marchand <david.marchand@redhat.com> wrote:
>
> > On Wed, Oct 2, 2019 at 9:40 PM Stephen Hemminger
> > <stephen@networkplumber.org> wrote:
> > > +struct lcore_config {
> > > +       pthread_t thread_id;       /**< pthread identifier */
> > > +       int pipe_master2slave[2];  /**< communication pipe with master */
> > > +       int pipe_slave2master[2];  /**< communication pipe with master */
> > > +
> > > +       lcore_function_t * volatile f; /**< function to call */
> > > +       void * volatile arg;       /**< argument of function */
> > > +       volatile int ret;          /**< return value of function */
> > > +
> > > +       uint32_t core_id;          /**< core number on socket for this lcore */
> > > +       uint32_t core_index;       /**< relative index, starting from 0 */
> > > +       uint16_t socket_id;        /**< physical socket id for this lcore */
> > > +       uint8_t core_role;         /**< role of core eg: OFF, RTE, SERVICE */
> > > +       uint8_t detected;          /**< true if lcore was detected */
> > > +       volatile enum rte_lcore_state_t state; /**< lcore state */
> > > +       rte_cpuset_t cpuset;       /**< cpu set which the lcore affinity to */
> > > +};
> >
> > There are still changes on the core_id, core_index, socket_id that I
> > am not confortable with (at this point).
> >
> > I prepared a series for -rc1 on ABI changes in EAL (that I will send shortly).
> > I took your patch without the changes on core_id, core_index and socket_id.
>
>
> Why, please be more precise.
>

I commented earlier that there were integer conversion with the fields
you changed.

core_id is ok, and a uint32_t would be fine, but this does not change the size.
socket_id needs investigation, but should be safe.
I am nervous about core_index, because it is used as a signed integer.

It looks too dangerous to blindly accept this change with the only
reason of saving space.
  

Patch

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index 0ee8533b133c..89811a622591 100644
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -23,10 +23,6 @@  Deprecation Notices
 * eal: The function ``rte_eal_remote_launch`` will return new error codes
   after read or write error on the pipe, instead of calling ``rte_panic``.
 
-* eal: The ``lcore_config`` struct and global symbol will be made private to
-  remove it from the externally visible ABI and allow it to be updated in the
-  future.
-
 * eal: both declaring and identifying devices will be streamlined in v18.11.
   New functions will appear to query a specific port from buses, classes of
   device and device drivers. Device declaration will be made coherent with the
diff --git a/doc/guides/rel_notes/release_19_11.rst b/doc/guides/rel_notes/release_19_11.rst
index 27cfbd9e38c6..e8d4f9d2ba28 100644
--- a/doc/guides/rel_notes/release_19_11.rst
+++ b/doc/guides/rel_notes/release_19_11.rst
@@ -110,6 +110,8 @@  ABI Changes
    Also, make sure to start the actual text at the margin.
    =========================================================
 
+* eal: The ``lcore_config`` struct and global symbol are now private.
+
 
 Shared Library Versions
 -----------------------
diff --git a/lib/librte_eal/common/eal_common_launch.c b/lib/librte_eal/common/eal_common_launch.c
index fe0ba3f0d617..cf52d717f68e 100644
--- a/lib/librte_eal/common/eal_common_launch.c
+++ b/lib/librte_eal/common/eal_common_launch.c
@@ -15,6 +15,8 @@ 
 #include <rte_per_lcore.h>
 #include <rte_lcore.h>
 
+#include "eal_private.h"
+
 /*
  * Wait until a lcore finished its job.
  */
diff --git a/lib/librte_eal/common/eal_private.h b/lib/librte_eal/common/eal_private.h
index 798ede553b21..e63eaa5d262d 100644
--- a/lib/librte_eal/common/eal_private.h
+++ b/lib/librte_eal/common/eal_private.h
@@ -10,6 +10,30 @@ 
 #include <stdio.h>
 
 #include <rte_dev.h>
+#include <rte_lcore.h>
+
+/**
+ * Structure storing internal configuration (per-lcore)
+ */
+struct lcore_config {
+	pthread_t thread_id;       /**< pthread identifier */
+	int pipe_master2slave[2];  /**< communication pipe with master */
+	int pipe_slave2master[2];  /**< communication pipe with master */
+
+	lcore_function_t * volatile f; /**< function to call */
+	void * volatile arg;       /**< argument of function */
+	volatile int ret;          /**< return value of function */
+
+	uint32_t core_id;          /**< core number on socket for this lcore */
+	uint32_t core_index;       /**< relative index, starting from 0 */
+	uint16_t socket_id;        /**< physical socket id for this lcore */
+	uint8_t core_role;         /**< role of core eg: OFF, RTE, SERVICE */
+	uint8_t detected;          /**< true if lcore was detected */
+	volatile enum rte_lcore_state_t state; /**< lcore state */
+	rte_cpuset_t cpuset;       /**< cpu set which the lcore affinity to */
+};
+
+extern struct lcore_config lcore_config[RTE_MAX_LCORE];
 
 /**
  * Initialize the memzone subsystem (private to eal).
diff --git a/lib/librte_eal/common/include/rte_lcore.h b/lib/librte_eal/common/include/rte_lcore.h
index c86f72eb12a8..0c683919564e 100644
--- a/lib/librte_eal/common/include/rte_lcore.h
+++ b/lib/librte_eal/common/include/rte_lcore.h
@@ -66,30 +66,6 @@  typedef cpuset_t rte_cpuset_t;
 } while (0)
 #endif
 
-/**
- * Structure storing internal configuration (per-lcore)
- */
-struct lcore_config {
-	unsigned detected;         /**< true if lcore was detected */
-	pthread_t thread_id;       /**< pthread identifier */
-	int pipe_master2slave[2];  /**< communication pipe with master */
-	int pipe_slave2master[2];  /**< communication pipe with master */
-	lcore_function_t * volatile f;         /**< function to call */
-	void * volatile arg;       /**< argument of function */
-	volatile int ret;          /**< return value of function */
-	volatile enum rte_lcore_state_t state; /**< lcore state */
-	unsigned socket_id;        /**< physical socket id for this lcore */
-	unsigned core_id;          /**< core number on socket for this lcore */
-	int core_index;            /**< relative index, starting from 0 */
-	rte_cpuset_t cpuset;       /**< cpu set which the lcore affinity to */
-	uint8_t core_role;         /**< role of core eg: OFF, RTE, SERVICE */
-};
-
-/**
- * Internal configuration (per-lcore)
- */
-extern struct lcore_config lcore_config[RTE_MAX_LCORE];
-
 RTE_DECLARE_PER_LCORE(unsigned, _lcore_id);  /**< Per thread "lcore id". */
 RTE_DECLARE_PER_LCORE(rte_cpuset_t, _cpuset); /**< Per thread "cpuset". */
 
diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
index c3653ebae46c..6e21f549051b 100644
--- a/lib/librte_eal/common/rte_service.c
+++ b/lib/librte_eal/common/rte_service.c
@@ -21,6 +21,8 @@ 
 #include <rte_memory.h>
 #include <rte_malloc.h>
 
+#include "eal_private.h"
+
 #define RTE_SERVICE_NUM_MAX 64
 
 #define SERVICE_F_REGISTERED    (1 << 0)
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index 7cbf82d37b0a..aeedf397764f 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -4,7 +4,6 @@  DPDK_2.0 {
 	__rte_panic;
 	eal_parse_sysfs_value;
 	eal_timer_source;
-	lcore_config;
 	per_lcore__lcore_id;
 	per_lcore__rte_errno;
 	rte_calloc;
diff --git a/lib/librte_eal/windows/eal/eal_thread.c b/lib/librte_eal/windows/eal/eal_thread.c
index 906502f90982..0591d4c7fb06 100644
--- a/lib/librte_eal/windows/eal/eal_thread.c
+++ b/lib/librte_eal/windows/eal/eal_thread.c
@@ -12,6 +12,7 @@ 
 #include <rte_common.h>
 #include <eal_thread.h>
 
+#include "eal_private.h"
 
 RTE_DEFINE_PER_LCORE(unsigned int, _lcore_id) = LCORE_ID_ANY;