Commit 9957a6c4 authored by Ramon Nou's avatar Ramon Nou
Browse files

Lock System for cargo

parent 7f9ef9c0

CHANGELOG.md

+2 −0
Original line number Diff line number Diff line
@@ -11,6 +11,8 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). 
  - Tests to cover proxy and (malleability) ([!222](https://storage.bsc.es/gitlab/hpc/gekkofs/-/merge_requests/222))

  - New fd generation method ([!225](https://storage.bsc.es/gitlab/hpc/gekkofs/-/merge_requests/202))

    - Use LIBGKFS_PROTECT_FD=1 to enable the original method of assignation and protection.

  - Lock system (server level) ([!233](https://storage.bsc.es/gitlab/hpc/gekkofs/-/merge_requests/233))

    - Use PROTECT_FILES_GENERATOR=1 and PROTECT_FILES_CONSUMER=1 to enable. Generator, creates transparent .lockgekko files that blocks the open (for some seconds) of any consumer. Multiple opens / closes for generator are managed.

    

### Changed 

  - Tests check ret for -1 instead of 10000 fd ([!320](https://storage.bsc.es/gitlab/hpc/gekkofs/-/merge_requests/320))

README.md

+5 −0
Original line number Diff line number Diff line
@@ -589,6 +589,11 @@ until the file is closed. The cache does not impact the consistency of the file 
When the user creates a fd, this is protected from normal fds with a recolocation. This theoretically protects the fd from being closed from outside. However a new fd assignation system has been developed and is activated by default.

- `LIBGKFS_PROTECT_FD=1` - Enable the original method of assignation and protection.



##### Lightweight File-Locking (server side)

Using two environment variables

- `LIBGKFS_PROTECT_FILES_GENERATOR=1` enables the application as generator, so a open will create (and increase) a file .lockgekko and close will remove it (or decrease its value). The behaviour only uses metadata at server side.

- `LIBGKFS_PROTECT_FILES_CONSUMER=1` enables the application as consumer, so a open will wait until the .lockgekko dissapears. The wait is limited to ~40 seconds. 



### Daemon

#### Logging

- `GKFS_DAEMON_LOG_PATH` - Path to the log file of the daemon.

include/client/env.hpp

+4 −0
Original line number Diff line number Diff line
@@ -69,6 +69,10 @@ static constexpr auto METRICS_IP_PORT = ADD_PREFIX("METRICS_IP_PORT"); 
#endif



static constexpr auto PROTECT_FD = ADD_PREFIX("PROTECT_FD");

static constexpr auto PROTECT_FILES_GENERATOR =

        ADD_PREFIX("PROTECT_FILES_GENERATOR");

static constexpr auto PROTECT_FILES_CONSUMER =

        ADD_PREFIX("PROTECT_FILES_CONSUMER");

static constexpr auto NUM_REPL = ADD_PREFIX("NUM_REPL");

static constexpr auto PROXY_PID_FILE = ADD_PREFIX("PROXY_PID_FILE");

namespace cache {

include/client/preload_context.hpp

+16 −0
Original line number Diff line number Diff line
@@ -140,6 +140,9 @@ private: 
    int replicas_;



    bool protect_fds_{false};

    bool protect_files_generator_{false};

    bool protect_files_consumer_{false};





    std::shared_ptr<gkfs::messagepack::ClientMetrics> write_metrics_;

    std::shared_ptr<gkfs::messagepack::ClientMetrics> read_metrics_;
@@ -322,6 +325,19 @@ public: 
    void

    protect_fds(bool protect);



    bool

    protect_files_generator() const;



    void

    protect_files_generator(bool protect);



    bool

    protect_files_consumer() const;



    void

    protect_files_consumer(bool protect);





    const std::shared_ptr<gkfs::messagepack::ClientMetrics>

    write_metrics();

src/client/gkfs_functions.cpp

+109 −5
Original line number Diff line number Diff line
@@ -48,6 +48,8 @@ 
#include <client/rpc/forward_data_proxy.hpp>

#include <client/open_dir.hpp>

#include <client/cache.hpp>

#include <string>

#include <string_view>



#include <common/path_util.hpp>

#ifdef GKFS_ENABLE_CLIENT_METRICS
@@ -116,6 +118,65 @@ check_parent_dir(const std::string& path) { 


namespace gkfs::syscall {



/**

 * @brief generate_lock_file

 * @param path

 * @param increase

 *

 * Creates, if it does not exist, a lock file, path+".lockgekko", empty

 * If increase is true, increase the size of the file +1

 * if increase is false, decrease the size of the file -1

 * If size == 0, delete the file

 * Using calls : forward_create, forward_stat, forward_remove, forward_decr_size

 * and forward_update_metadentry_size Proxy not supported

 */

void

generate_lock_file(const std::string& path, bool increase) {

    auto lock_path = path + ".lockgekko";

    if(increase) {

        auto md = gkfs::utils::get_metadata(lock_path);

        if(!md) {

            gkfs::rpc::forward_create(lock_path, 0777 | S_IFREG, 0);

        }

        gkfs::rpc::forward_update_metadentry_size(lock_path, 1, 0, false, 0);

    } else {

        auto md = gkfs::utils::get_metadata(lock_path);

        if(md) {

            if(md.value().size() == 1) {

                LOG(DEBUG, "Deleting Lock file {}", lock_path);

                gkfs::rpc::forward_remove(lock_path, false, 0);

            } else {

                gkfs::rpc::forward_decr_size(lock_path, md.value().size() - 1,

                                             0);

            }

        }

    }

}



/**

 * @brief generate_lock_file

 * @param path

 *

 * Test if the lock file exists, if it exists, wait 0.5 second and check again

 * (max 80 times) Using calls : forward_stat

 */

void

test_lock_file(const std::string& path) {

    auto lock_path = path + ".lockgekko";

    auto md = gkfs::utils::get_metadata(lock_path);

    if(md) {

        LOG(DEBUG, "Lock file exists {} --> {}", lock_path, md->size());

        for(int i = 0; i < 80; i++) {

            if(!md) {

                break;

            }

            std::this_thread::sleep_for(std::chrono::milliseconds(500));

            md = gkfs::utils::get_metadata(lock_path);

        }

    }

}





/**

 * gkfs wrapper for open() system calls

 * errno may be set
@@ -168,9 +229,14 @@ gkfs_open(const std::string& path, mode_t mode, int flags) { 
                return -1;

            }

        } else {

            // file was successfully created. Add to filemap

            return CTX->file_map()->add(

            auto fd = CTX->file_map()->add(

                    std::make_shared<gkfs::filemap::OpenFile>(path, flags));

            // CREATE_MODE

            if(CTX->protect_files_generator()) {

                generate_lock_file(path, true);

            }

            // file was successfully created. Add to filemap

            return fd;

        }

    } else {

        auto md_ = gkfs::utils::get_metadata(path);
@@ -228,7 +294,7 @@ gkfs_open(const std::string& path, mode_t mode, int flags) { 
                    return -1;

                }

            }



            // RENAMED OR SYMLINK NOT PROTECTED

            return CTX->file_map()->add(

                    std::make_shared<gkfs::filemap::OpenFile>(new_path, flags));

        }
@@ -248,9 +314,19 @@ gkfs_open(const std::string& path, mode_t mode, int flags) { 
            return -1;

        }

    }



    return CTX->file_map()->add(

    // NORMAL OPEN

    auto fd = CTX->file_map()->add(

            std::make_shared<gkfs::filemap::OpenFile>(path, flags));





    if(CTX->protect_files_consumer()) {

        test_lock_file(path);

    }



    if(CTX->protect_files_generator()) {

        generate_lock_file(path, true);

    }

    return fd;

}



/**
@@ -1498,6 +1574,14 @@ gkfs_getdents(unsigned int fd, struct linux_dirent* dirp, unsigned int count) { 
    while(pos < open_dir->size()) {

        // get dentry fir current position

        auto de = open_dir->getdent(pos);

        if(CTX->protect_files_consumer() or CTX->protect_files_generator()) {

            // if de.name ends with lockgekko jump to the next file

            if(de.name().size() >= 10 &&

               de.name().substr(de.name().size() - 10) == ".lockgekko") {

                pos++;

                continue;

            }

        }

        /*

         * Calculate the total dentry size within the kernel struct

         * `linux_dirent` depending on the file name size. The size is then
@@ -1567,6 +1651,14 @@ gkfs_getdents64(unsigned int fd, struct linux_dirent64* dirp, 
    struct linux_dirent64* current_dirp = nullptr;

    while(pos < open_dir->size()) {

        auto de = open_dir->getdent(pos);

        if(CTX->protect_files_consumer() or CTX->protect_files_generator()) {

            // if de.name ends with lockgekko jump to the next file

            if(de.name().size() >= 10 &&

               de.name().substr(de.name().size() - 10) == ".lockgekko") {

                pos++;

                continue;

            }

        }

        /*

         * Calculate the total dentry size within the kernel struct

         * `linux_dirent` depending on the file name size. The size is then
@@ -1662,6 +1754,11 @@ gkfs_close(unsigned int fd) { 
                        CTX->file_map()->get(fd)->path());

            }

        }



        if(CTX->protect_files_generator()) {

            auto path = CTX->file_map()->get(fd)->path();

            generate_lock_file(path, false);

        }

        // No call to the daemon is required

        CTX->file_map()->remove(fd);

        return 0;
@@ -1791,6 +1888,13 @@ gkfs_get_file_list(const std::string& path) { 


    while(pos < open_dir->size()) {

        auto de = open_dir->getdent(pos++);

        if(CTX->protect_files_consumer() or CTX->protect_files_generator()) {

            // if de.name ends with lockgekko jump to the next file

            if(de.name().size() >= 10 &&

               de.name().substr(de.name().size() - 10) == ".lockgekko") {

                continue;

            }

        }

        file_list.push_back(de.name());

    }

    return file_list;